Abdul, JM, Vigneswaran, S, Shon, HK, Nathaporn, A & Kandasamy, J 2009, 'Comparison of granular activated carbon bio-sorption and advanced oxidation processes in the treatment of leachate effluent', Korean Journal of Chemical Engineering, vol. 26, no. 3, pp. 724-730.
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Al-Mahmoud, F, Castel, A, François, R & Tourneur, C 2009, 'Strengthening of RC members with near-surface mounted CFRP rods', Composite Structures, vol. 91, no. 2, pp. 138-147.
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Areerachakul, N, Kitiphatmontree, M, Kandasamy, J, Kus, B, Duangduen, C, Pivsa-Art, S & Vigneswaran, S 2009, 'Submerged Membrane System with Biofilter as a Treatment to Rainwater', Water, Air, & Soil Pollution: Focus, vol. 9, no. 5-6, pp. 431-438.
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Rainwater has been used as drinking water in Thailand for centuries especially in the rural parts and is accepted as an important water resource. From past to present, the quality of rainwater has changed with the landuse of the landscape, and its water quality is influenced by a diverse range of conditions such as the management of pollutant sources, the catchment condition, wind and meteorological conditions, and the location of rainwater collection points. In this study, the quality of rainwater collected off roofs at several locations was examined. Granular activated carbon (GAC) filtration was used as a pretreatment to microfiltration (MF) to remove the dissolved organic matter (DOC). After an initial adsorption period, the biofilm that formed on the GAC (biofilter) was found to remove DOC by up to 40%, 35%, and 15% for bed filter depths of 15, 10, and 5 cm, respectively. Biofilters also removed nitrate and phosphate by more than 80% and 35%. The hollow fiber membrane microfiltration with pore size of 0.1 μm was used to treat the effluent from biofiltration to remove the microorganisms/pathogens in the rainwater. Although there was no significant additional removal of DOC by MF, the biofilter removed all microorganisms. The use of biofilters as pretreatment to MF/UF could remove a higher amount of DOC, remove microorganisms, increase the membrane treatment efficiency, and reduce membrane fouling.
Aryal, R, Kandasamy, J, Vigneswaran, S, Naidu, R & Lee, SH 2009, 'Review of Stormwater Quality, Quantity and Treatment Methods Part 2: Stormwater: Quality Modelling', Environmental Engineering Research, vol. 14, no. 3, pp. 143-149.
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In this paper, review of stormwater quality and quantity in the urban environment is presented. The review is presented in three parts. This second part reviews the mathematical techniques used in stormwater quality modelling and has been undertaken by examining a number of models that are in current use. The important features of models are discussed.
Aryal, R, Lebegue, J, Vigneswaran, S, Kandasamy, J & Grasmick, A 2009, 'Identification and characterisation of biofilm formed on membrane bio-reactor', Separation and Purification Technology, vol. 67, no. 1, pp. 86-94.
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Experiments were conducted in a laboratory scale membrane bio-reactor (MBR) system equipped with a side stream flat sheet membrane. Six runs lasting different durations (2, 4, 6, 9, 15 and 20 days) were conducted at an aeration rate of 2 m3 h-1 m-2 to understand the temporal variation of chemistry of foulant that attached on the membrane surface. The foulant attached on the membrane surface was extracted with 0.5% (v/v) NaOH solution and the extract was analysed using fluorescent spectroscopy and size exclusion chromatography. Variation of low- and high-molecular weight substances with evolution of time was compared. The results showed that the nature of foulant changed with the evolution of time. Four runs conducted for a short duration (2, 4, 6 and 9 days), low-molecular weight substances were dominant in the foulant whereas for long duration runs (15 and 20 days), high-molecular weight substances were mainly observed. Moreover, the foulant close to the membrane surface contained mainly protein and soluble microbial by-products.
Aryal, RK, Lebegue, J, Shon, HK, Vigneswaran, S, Kandasamy, J & Grasmick, A 2009, 'Temporal variation of foulant characteristics in membrane bioreactor', DESALINATION AND WATER TREATMENT, vol. 6, no. 1-3, pp. 69-73.
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Many studies have been performed to analyse the influence of compounds present in different fractions of the membrane foulants. The aim of this study was to reveal the changing chemistry of compounds present in membrane foulant with the evolution of time. Membrane fouling in a side stream membrane bioreactor (MBR) reactor was investigated. Constant flux filtration was employed in an MBR operation. Air bubbles were injected at 2 m3 h1 m2 for six different durations (2, 4, 6, 9, 15 and 20 days) of MBR operation. The foulant on the membrane surface was extracted using NaOH solution (5%) and analysed using fluorescent spectroscopy. The spectra showed the changing chemistry of foulant with the evolution of time. It showed low molecular weight substances such as amino acids and small aromatic proteins were dominant in the foulant at the beginning of the experiment but its concentration decreased with time. On the other hand BOD5 type substances concentration increased with time from the beginning of the experiment up to 9 days and there after decreased. The concentration of larger molecular weight soluble microbial by-products increased with evolution of time. Air bubbles at two aeration rate of 1m3 h1m2 and 2 m3 h1 m2 were also injected from the bottom of the membrane tanks to produce shear stresses on the membrane surface during 5 days of MBR operation to compare the effect of aeration in fouling propensity.
Aye, TM, Hedley, MJ, Loganathan, P, Lefroy, RDB & Bolan, NS 2009, 'Effect of organic and inorganic phosphate fertilizers and their combination on maize yield and phosphorus availability in a Yellow Earth in Myanmar', NUTRIENT CYCLING IN AGROECOSYSTEMS, vol. 83, no. 2, pp. 111-123.
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Phosphorus (P) deficiency is a major constraint for crop production in many parts of the world including Myanmar and field research into management of P fertilizers and P responsiveness of crops on infertile soils has been limited. The purpose of this study is to determine maize yield response to different forms of P fertilizers on an acidic (pH 4.9) P deficient (Olsen-P 8 mg kg -1) Yellow Earth (Acrisol) in Southern Shan State, Myanmar and to establish relationships between soil Olsen-P test values (0.5 M sodium bicarbonate extracted P) and maize yield. Field experiments were conducted during two cropping seasons. There were 15 treatments in total: P was applied at seven rates of a soluble P fertilizer as Triple superphosphate (TSP) (0-120 kg P ha-1) to establish a P response curve; one rate of a partially soluble P fertilizer (Chinese partially acidulated phosphate rock, CPAPR) and two organic P fertilizers (farmyard manure (FYM) and Tithonia diversifolia) at 20 kg P ha-1; combination of TSP and CPAPR at 20 kg P ha-1 with FYM and Tithonia at 20 kg P ha-1; an additional treatment (TSP 20 kg P ha-1 plus 2.5 t ha-1 dolomite) for assessing the liming effect of a local dolomite. In Year 1, applications of TSP at 40-60 kg P ha-1 produced near maximum grain yields, whereas in Year 2 this could be achieved with a reapplication of 20-30 kg P ha-1 on top of the residual value of the Year 1 application. In both years, CPAPR, TSP and Tithonia at 20 kg P ha-1 significantly increased maize grain yield, but FYM failed to increase grain yield. In Year 1, CPAPR and TSP effects on grain yield were higher than that of Tithonia but in Year 2 the effects were same for all these three treatments. In both years the combination of FYM (20 kg P ha -1) with TSP (20 kg P ha-1) produced significantly higher grain yield than TSP at 20 kg P ha-1 whereas 40 kg P ha-1 of TSP application did not significantly increase grain yield over the TSP application at 20 kg P ha-1. Similar results were o...
Ball, JE 2009, 'Discussion of “Automatic Calibration of the U.S. EPA SWMM Model for a Large Urban Catchment” by J. Barco, K. M. Wong, and M. K. Stenstrom', Journal of Hydraulic Engineering, vol. 135, no. 12, pp. 1108-1110.
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Bao, C, Hao, H, Li, Z-X & Zhu, X 2009, 'Time-varying system identification using a newly improved HHT algorithm', Computers & Structures, vol. 87, no. 23-24, pp. 1611-1623.
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Chanan, A, Kandasamy, J & Simmons, B 2009, 'Benefits of local government and university research alliances', Proceedings of the Institution of Civil Engineers - Municipal Engineer, vol. 162, no. 2, pp. 111-116.
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Local government plays an integral role in the Australian economy with a cumulative annual expenditure of over Aus$20 billion representing around 2% of Australian GDP. Local government authorities employ around 1·3% of the Australian workforce and provide a wide range of services and infrastructure. There is a general lack of appreciation among council staff of the value of collaboration with universities and vice versa. However, staff at Kogarah Municipal Council, having been involved in partnership projects with universities, strongly value the benefits of such collaborations. Councils can provide a ‘one-stop-shop’ for applied research and its application for a range of disciplines from science and technology to arts and policy studies.
Chanan, A, Kandasamy, J, Vigneswaran, S & Sharma, D 2009, 'A gradualist approach to address Australia's urban water challenge', Desalination, vol. 249, no. 3, pp. 1012-1016.
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There is growing consensus worldwide against the conventional centralised approach to water management, and a âsoft pathâ for water management has emerged as a sustainable alternative. A âsoft pathâ for water management emphasizes the optimization of end-use efficiency, small-scaled management systems, incorporates fit-for-purpose water use, and recommends the use of diverse, locally appropriate and commonly decentralised infrastructures. However, large-scale desalination plants are currently being built for almost all metropolitan centres in Australia to ensure water supply security. Unlike âsoft pathâ for water management, large-scale desalination plants embody the traditional urban water supply approach. In spite of knowledge and values relating to the water cycle having shifted towards âsoft pathâ, the old organisational framework is believed to be hindering its adoption. Perhaps, therefore major water utilities in recent times have opted for the ideologically easier option of large-scale desalination conforming to the existing framework, instead of choosing a âsoft pathâ for water management with potential for decentralised management. This paper critically reviews the urban water management direction in metropolitan Australia and puts forward a âgradualist approachâ. It incorporates a comprehensive non-potable water reuse program necessary to build the familiarity and trust in water reuse, as a first step before introducing the idea of potable reuse.
Chiemchaisr, C, Passananon, S, Ngo, HH & Vigneswaran, S 2009, 'Simultaneous removal of particles and dissolved organic matter in floating media filter for surface water treatment', DESALINATION AND WATER TREATMENT, vol. 11, no. 1-3, pp. 109-114.
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This research investigated the performance of fl oating media fi lter in removing particles and dissolved organic matter from surface water. Pilot-scale study consists of fl oating plastic media pre-fi lter connected with either granular activated carbon (GAC) or sponge biological fi lter (BF) bed. In the fl oating plastic media fi lter, coagulation and fl occulation processes using poly-aluminum chloride (PACl) as coagulant at an optimum dose of 8 mg/L helped removing particles from raw water. The fl oating media fi lter was operated a fi ltration rate of 11 m3/m2.h whereas those in GAC and BF units were maintained at 2 m3/m2.h. Continuous operation for over 120 days gave 98% and 99% average removal effi ciencies of turbidity and UV254 in fl oating media fi lter in combination with GAC unit whereas and 78% and 52% removal effi ciencies of turbidity and UV254 removal were obtained in fl oating media fi lter in combination with BF. The removal of dissolved organic carbon in GAC and BF units reduced chlorine demand for disinfection by 29% and 14%. It could also reduce the sum of trihalomethane (THMs) ratio from 1.1 to 0.1 and 0.5 respectively.
Chinu, KJ, Johir, AH, Vigneswaran, S, Shon, HK & Kandasamy, J 2009, 'Biofilter as pretreatment to membrane based desalination: Evaluation in terms of fouling index', DESALINATION, vol. 247, no. 1-3, pp. 77-84.
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The removal of particulate matter and dissolved organic matter from seawater by the use of biofiltration was investigated. Granular activated carbon (GAC) and anthracite were used as biofilter media at two different filtration velocities. Filtrate quality was measured in terms of silt density index (SDI), modified fouling index (MFI) and turbidity removal. Reverse osmosis (RO) was used as a post-treatment. Both biofilters demonstrated similar fouling reduction behavior in terms of SDI and MFI. Fouling potential in terms of MFI values decreased to 10 s/L2 within the first 10â15 days of operation and kept constant up to the remaining experimental period of 55 days of operation for both GAC and anthracite biofilter. The filtrate turbidity was steady after 10 days and remained low at a value of 0.2â0.3 NTU and 0.28â0.31 NTU for anthracite and GAC biofilter, respectively. Furthermore, the headloss development was low and within 20 cm for biofilter operated at a low velocity of 5 m/h. A post-treatment of reverse osmosis after a pretreatment of GAC and anthracite biofilters showed a reduction in normalized flux decline (J/J0) from 0.22 to 0.12 and 0.35 to 0.21 during the first 20 h, respectively. The RO flux for seawater declined at a faster rate and continued even after 3 days when no pretreatment was provided.
Coronelli, D, Castel, A, François, R & Cleland, D 2009, 'Modelling the response of prestressed beams with corroded reinforcement', European Journal of Environmental and Civil Engineering, vol. 13, no. 6, pp. 653-669.
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Coronelli, D, Castel, A, Vu, NA & François, R 2009, 'Corroded post-tensioned beams with bonded tendons and wire failure', Engineering Structures, vol. 31, no. 8, pp. 1687-1697.
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Coulibaly, P, Babovic, V, Cluckie, I, Mynett, A & Ball, J 2009, '2009 Special Issue of the Journal of Hydroinformatics on Advances in Hydroinformatics Preface', JOURNAL OF HYDROINFORMATICS, vol. 11, no. 3-4, pp. 165-165.
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Coulibaly, P, Babovic, V, Cluckie, I, Mynett, A & Ball, J 2009, 'Preface: 2009 Special issue of the journal of Hydroinformatics on advances in hydroinformatics', Journal of Hydroinformatics, vol. 11, no. 3-4, p. 165.
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Crews, K 2009, 'Australian Journal of Structural Engineering: Preface', Australian Journal of Structural Engineering, vol. 9, no. 3.
da Rocha, CG & Sattler, MA 2009, 'A discussion on the reuse of building components in Brazil: An analysis of major social, economical and legal factors', Resources, Conservation and Recycling, vol. 54, no. 2, pp. 104-112.
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Dackermann, U, Li, J & Samali, B 2009, 'Damage Identification in Timber Bridges Utilising the Damage Index Method and Neural Network Ensembles', Australian Journal of Structural Engineering, vol. 9, no. 3, pp. 181-194.
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Many of Australia's timber bridges are in aged and decayed conditions. In order to ensure the reliability of these structures and the safety of the public, condition assessment, damage detection and safety evaluation is necessary. This paper presents a damage identification procedure, which is based on global change of vibration characteristics of a structure. The developed method utilises the damage index (DI) method in combination with neural network techniques to identify damage in numerical and experimental timber beam structures. The neural network ensemble approach is utilised in order to respect important diversities of different modes and to integrate individual characteristics of vibrational mode separated damage features. The method considers field testing issues associated with measurement noise, limited number of sensor arrays and environmental fluctuations. The results of damage detection using the proposed approach demonstrate its ability to determine the location and severity of all present damage cases. The outcomes show that the developed damage detection method is effective, robust and reliable.
Dahou, Z, Mehdi Sbartaï, Z, Castel, A & Ghomari, F 2009, 'Artificial neural network model for steel–concrete bond prediction', Engineering Structures, vol. 31, no. 8, pp. 1724-1733.
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De Silva, P, Bucea, L & Sirivivatnanon, V 2009, 'Chemical, microstructural and strength development of calcium and magnesium carbonate binders', CEMENT AND CONCRETE RESEARCH, vol. 39, no. 5, pp. 460-465.
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Ding, L, Hao, H & Zhu, X 2009, 'Evaluation of dynamic vehicle axle loads on bridges with different surface conditions', Journal of Sound and Vibration, vol. 323, no. 3-5, pp. 826-848.
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El Saliby, I, Okour, Y, Shon, HK, Kandasamy, J & Kim, IS 2009, 'Desalination plants in Australia, review and facts', DESALINATION, vol. 247, no. 1-3, pp. 1-14.
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Australia is the driest continent on earth and despite this the installed desalination capacity is still around 1% of the total world's desalination capacity. This paper reviews the main seawater issues considered in every desalination projectâthe history, the present situation and the future of desalination in Australia, the suitability of applying reverse osmosis (RO) and the project details of two desalination plants (Sydney and Perth). Ocean currents, seawater temperature and salinity are signifi cant indicators in the assessment of the feasibility of desalination as they aff ect the production costs, the maintenance frequency and the quality of the product water. Seawater reverse osmosis (SWRO) is the only type of desalination technology currently used or proposed for future large-scale desalination plants in Australia. Every capital city except Darwin has considered building at least one desalination plant as a means of providing water security after several years of unprecedented drought that has signifi cantly reduced dam storage levels. Perth was the fi rst major city to use desalinated water for drinking water supply and by early 2009 Sydney will be the second city. Thirteen other large-scale SWRO plants are being planned or proposed at several locations for the purpose of supplying drinking water.
El Saliby, IJ, Okour, YH, Shon, HK, Vigneswaran, S, Kandasamy, J & Kim, J-H 2009, 'Detailed Investigation on the Effect of Washing TiO2 Prepared from Tisalts Flocculated Wastewater Sludge', Journal of Advanced Oxidation Technologies, vol. 12, no. 2, pp. 194-201.
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AbstractIn this study, the effect of washing TiO
Elmir, M, Mehdaoui, R, Castel, A, Hamouine, A & François, R 2009, 'Vibratory analysis of a composite beam (reinforced concrete) subject to corrosion', International Review of Mechanical Engineering, vol. 3, no. 1, pp. 100-103.
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This work is an attempt to study, with an experimental approach the effect of corrosion on the dynamic behaviour of the reinforced concrete structures by measuring the Eigen frequencies. For this purpose a test was applied on reinforced concrete healthy and corroded beams subjected to a vibratory mechanical excitation. For this test we made use of a vibrating pot and a signal analyzer. The spectral response of each beam gives information in the form of a signal which allows the measurement of these Eigen frequencies so that one can determine the effect of corrosion on the dynamic behaviour of the beam which represents the originality of our experimental approach. © 2009 Praise Worthy Prize S.r.l. - All rights reserved.
Fang, F, Ni, B-J & Yu, H-Q 2009, 'Estimating the kinetic parameters of activated sludge storage using weighted non-linear least-squares and accelerating genetic algorithm', Water Research, vol. 43, no. 10, pp. 2595-2604.
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Fang, F, Ni, B-J, Li, X-Y, Sheng, G-P & Yu, H-Q 2009, 'Kinetic analysis on the two-step processes of AOB and NOB in aerobic nitrifying granules', Applied Microbiology and Biotechnology, vol. 83, no. 6, pp. 1159-1169.
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Fatahi, B, Khabbaz, H & Indraratna, B 2009, 'Parametric studies on bioengineering effects of tree root-based suction on ground behaviour', ECOLOGICAL ENGINEERING, vol. 35, no. 10, pp. 1415-1426.
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Using native vegetation to improve soil stiffness, stabilise slopes and control erosion is a rapidly evolving process. A theoretical model previously developed by the authors for the rate of tree root water uptake together with an associated numerical simulation is used to study the effects of a wide range of soil, tree, and atmospheric parameters on partially saturated ground. The influence of different parameters on the maximum initial rate of root water uptake is investigated through parametric and sensitivity analyses. Field measurements taken from previously published literature are compared with numerical predictions for validation. The rate of selected parameters such as potential transpiration and its distribution, suction at wilting point, the coefficient of permeability and the distribution of root length density are studied in detail. The analysis shows that the rate of potential transpiration increases the soil matric suction and ground settlement, while the potential transpiration rate has an insignificant effect on the distribution of soil suction. Root density distribution factors affect the size of the influence zone. Suction at the wilting point increases the soil matric suction and ground settlement, whereas the saturation permeability decreases the maximum soil matric suction generated. The analysis confirms that the most sensitive parameters, including the coefficients of the tree root system, the transpiration rate, the permeability of the soil and its suction at the wilting point should be measured or estimated accurately for an acceptable prediction of ground conditions in the vicinity of trees. © 2009 Elsevier B.V. All rights reserved.
Fu, Q, Wang, G, Lin, W & Huang, J 2009, 'One‐pot preparation of 3‐miktoarm star terpolymers via “click chemistry” and atom transfer nitroxide radical coupling reaction', Journal of Polymer Science Part A: Polymer Chemistry, vol. 47, no. 3, pp. 986-990.
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Fu, Q, Zhang, Z, Lin, W & Huang, J 2009, 'Single-Electron-Transfer Nitroxide-Radical-Coupling Reaction at Ambient Temperature: Application in the Synthesis of Block Copolymers', Macromolecules, vol. 42, no. 13, pp. 4381-4383.
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Gerber, C & Crews, K 2009, 'Timber Stressed-Skin Panels: Design Guidelines for Australian Practice', Australian Journal of Structural Engineering, vol. 9, no. 3, pp. 207-216.
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this paper puts forward a design procedure and proposes, in the form of an amendment to Section 5 of AS1720.1-1997, to include these directives in a future edition of the design code. The design procedure discussed herein is thorough in scope and straightforward in application. It addresses the composite characteristics of SSP structures - composite action and tributary width of the sheathing. It provides clear guidelines for the assessment of both aspects. It also imposes a systematic verification of the different stresses experienced by the structure. This particular section of the design procedure considers both AS1720.1-1997 and Eurocode 5 (European Committee for Standardisation, 1995). In addition, a method to account for the two-way action ability of SSP structures is also proposed in the design procedure, which includes two equations derived by Gerber (2007). For defined applications, acceptable assessments of the load distribution in SSP systems are achieved with these two equations for loading on an exterior and interior joist, respectively.
Glamore, WC & Indraratna, B 2009, 'Tidal-forcing groundwater dynamics in a restored coastal wetland: implications of saline intrusion', Australian Journal of Earth Sciences, vol. 56, no. 1, pp. 31-40.
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Golab, AN & Indraratna, B 2009, 'Occurrence and consequences of acid sulphate soils and methods of site remediation', Geomechanics and Geoengineering, vol. 4, no. 3, pp. 201-208.
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© 2009 Taylor & Francis. The oxidation of sulphides in acid sulphate soils (ASS) causes the acidification of many Australian coastal river systems. The acidity negatively impacts upon coastal ecosystems, aquaculture, agriculture and concrete and steel infrastructure. In the low-lying floodplains, relatively deep surface drains fitted with one-way floodgates lower the watertable, thereby exposing the sulphidic minerals to oxidation. On the Broughton Creek floodplain in SE Australia, four distinct remediation strategies have been developed to tackle the issue of acidification by ASS: (i) simple V-notch weirs that raise the level of the watertable surrounding the drains thereby submerging the pyrite and preventing the further formation of acidity; (ii) modified two-way floodgates that allow the inflow of tidal water into the drains, thereby buffering the acidity within the drain before it enters the river and raising the level of the watertable surrounding the drain; (iii) lateral impermeable lime barriers that both prevent oxidation of pyrite by stopping the downward movement of oxygen into the soil and neutralise the acidity in the groundwater; and (iv) permeable reactive barriers (PRB) that passively intercept the groundwater flow and neutralise the acidity. Each remediation strategy has a distinct role to suit the different terrain and groundwater conditions.
Golab, AN, Peterson, MA & Indraratna, B 2009, 'Selection of permeable reactive barrier materials for treating acidic groundwater in acid sulphate soil terrains based on laboratory column tests', Environmental Earth Sciences, vol. 59, no. 1, pp. 241-254.
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Grover, DP, Zhang, ZL, Readman, JW & Zhou, JL 2009, 'A comparison of three analytical techniques for the measurement of steroidal estrogens in environmental water samples', Talanta, vol. 78, no. 3, pp. 1204-1210.
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Research into the analysis and monitoring of steroidal estrogens has grown significantly over the last decade, resulting in the emergence of a range of applicable techniques. In this study, three popular techniques, gas chromatography-mass spectrometry (GC-MS), gas chromatography-tandem mass spectrometry (GC-MS-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS) for the analysis of three highly potent steroidal estrogens in the aquatic environment have been compared. It has been observed that overall, the three techniques appear comparable in generating similar estrogen concentrations for river and effluent samples. Of the three techniques, the GC-MS technique is the simplest to operate, but fails to detect the estrogens at the lower-end of environmentally relevant concentrations. The tandem MS techniques are more selective than MS, and therefore able to detect lower concentration levels of the three steroidal estrogens of interest. However, the LC-MS-MS technique is more susceptible to matrix interferences for the analysis of samples, resulting in a reduction of the signal-to-noise ratio and a subsequent reduction in reliability and stability compared to GC-MS-MS. With the GC-MS-MS technique offering increased selectivity, the lowest limits of detection, and no false positive identification, it is recommended to be the preferred analytical technique for routine analysis of estrogens in environmental water samples. © 2009 Elsevier B.V. All rights reserved.
Guo, W, Ngo, H-H, Palmer, CG, Xing, W, Hu, AY-J & Listowski, A 2009, 'Roles of sponge sizes and membrane types in a single stage sponge-submerged membrane bioreactor for improving nutrient removal from wastewater for reuse', DESALINATION, vol. 249, no. 2, pp. 672-676.
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Sponge not only can reduce membrane fouling by means of mechanical cleaning and maintain a balance of suspended-attached microorganisms in submerged membrane bioreactor (SMBR), but also can enhance dissolved organic matter and nutrient removal. This study investigated the performance of three different sizes of sponge (S28â30/45R, S28â30/60R and S28â30/90R) associated with continuous aerated SMBR. A laboratory-scale single stage sponge-SMBR (SSMBR) showed high performance for removing dissolved organic matter (>96%) and PO4âP (>98.8), while coarse sponges such as S28â30/45R, S28â30/60R could achieve more than 99% removal of NH4âN. When three-size sponges (S28â30/45R, S28â30/60R and S28â30/90R) were mixed at a ratio of 1:1:1 and in conjunction with two kinds of membranes (0.1 μm hollow fiber and 2 μm nonwoven), the SSMBR system has proved its generic merits of superior treated effluent quality and less membrane fouling. The NH4âN and PO4âP removal were found excellent, which were more than 99.8% and over 99% respectively. Molecular weight distribution also indicated that major fractions of organic matter could be successfully removed by SSMBR.
Guo, W, Xing, W, Ngo, H, Hu, YA, Palmer, CG & Zhang, R 2009, 'Enhancement of Organics removal by an Integrated Nonwoven Media Biofiter-submerged Membrane Adsorption Hybrid System', Journal of Applied Membrane Science & Technology, vol. 9, no. 1, pp. 1-8.
Hao, X, Wang, Q, Zhang, X, Cao, Y & Mark Loosdrecht, CMV 2009, 'Experimental evaluation of decrease in bacterial activity due to cell death and activity decay in activated sludge', Water Research, vol. 43, no. 14, pp. 3604-3612.
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Haskett, M, Oehlers, DJ, Mohamed Ali, MS & Wu, C 2009, 'Rigid body moment–rotation mechanism for reinforced concrete beam hinges', Engineering Structures, vol. 31, no. 5, pp. 1032-1041.
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Haskett, M, Oehlers, DJ, Mohamed Ali, MS & Wu, C 2009, 'Yield Penetration Hinge Rotation in Reinforced Concrete Beams', Journal of Structural Engineering, vol. 135, no. 2, pp. 130-138.
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Hassan, MH, Kalam, MA, Mahlia, TMI, Aris, I, Nizam, MK, Abdullah, S & Ali, Y 2009, 'Experimental Test of a New Compressed Natural Gas Direct Injection Engine', Energy & Fuels, vol. 23, no. 10, pp. 4981-4987.
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HIBBERD, A, MASKAOUI, K, ZHANG, Z & ZHOU, J 2009, 'An improved method for the simultaneous analysis of phenolic and steroidal estrogens in water and sediment', Talanta, vol. 77, no. 4, pp. 1315-1321.
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This paper describes an improved method for the extraction and analysis of seven endocrine disrupting chemicals with wide-ranging polarities from water and sediments using gas chromatography-tandem mass spectrometry (GC-MS/MS). The analytes were 4-tert-octylphenol, 4-nonylphenol, bisphenol A, estrone, 17β-estradiol, 17α-ethynylestradiol and 16α-hydroxyestrone. The optimised GC-MS/MS method produces increased selectivity and sensitivity compared to GC-MS, with limit of detection ranging from 0.01 to 0.49 ng L-1 in water and from 0.05 to 0.14 ng g-1 in sediment. Extraction from aqueous samples was performed by solid-phase extraction (SPE) and from sediment samples by microwave-assisted extraction (MAE). The improved method for the clean-up of sediment extracts carried out by SPE enhanced EDC recovery (86-102%) while reducing matrix interference and sample drying time. Derivatisation of final sample extracts was achieved using N,O-bis(trimethylsilyl)trifluoroacetamide and pyridine, and their stability was enhanced by reconstituting the derivatised extracts with hexane. The method was validated by spiking experiments which showed good recovery and reproducibility. The method was applied to samples taken from the Medway estuary in Kent, UK, where non-conservative behaviour of EDCs was demonstrated. © 2008 Elsevier B.V. All rights reserved.
Ho, DP, Vigneswaran, S & Ngo, HH 2009, 'Photocatalysis-membrane hybrid system for organic removal from biologically treated sewage effluent', SEPARATION AND PURIFICATION TECHNOLOGY, vol. 68, no. 2, pp. 145-152.
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The application of semiconductor photocatalysis in treating wastewater has attracted growing interest due to its complete mineralisation of organic matter. Furthermore, coupling of photocatalytic process with microfiltration provided considerable advantages over the conventional methods. In this study, the photocatalytic reactivity of the catalysts was assessed at different operating conditions. The results show that the dissolved organic carbon (DOC) content was halved at a concentration of 1.0 g/L of TiO2. With the addition of flocculant FeCl3, the oxidation process was significantly improved further by another 30%. The recovery of TiO2 upon photooxidation process was achieved by coupling the photocatalysis reactor with a low energy submerged membrane reactor. The results show superior DOC degradation of more than 80% by this hybrid system. Moreover, it was demonstrated that photosensitization with TiO2/UV could effectively reduce membrane fouling and enhance the permeate flux of the submerged membrane reactor. © 2009 Elsevier B.V. All rights reserved.
Hossain, FM, Murch, GE, Belova, IV & Turner, BD 2009, 'Electronic, optical and bonding properties of CaCO3 calcite', Solid State Communications, vol. 149, no. 29-30, pp. 1201-1203.
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Howe, AJ, Rodríguez, JF & Saco, PM 2009, 'Surface evolution and carbon sequestration in disturbed and undisturbed wetland soils of the Hunter estuary, southeast Australia', Estuarine, Coastal and Shelf Science, vol. 84, no. 1, pp. 75-83.
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Hu, H, Li, Y & Wang, J 2009, 'Structural design and dynamic characteristics analysis for a magneto-rheological gun recoil shock absorber under impact load', Zhongguo Jixie Gongcheng/China Mechanical Engineering, vol. 20, no. 4, pp. 389-393.
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A full-scale mock-up for MR shock absorber characterized with multistage slotted and smoothness disposal under impact load was firstly established. Considering the dynamic of MR shock absorber under impact load, an inertia factor was introduced to Herschel-Bulkley model, which led to two revised models, named as Herschel-Bulkley-Inertia model. And a suit of real-time measuring and controlling simulation experimental platform including hardware and software for dynamic response of MR gun recoil shock absorber under impact load was developed. The parameters in Bingham-Inertia model and Herschel-Bulkley-Inertia model were identificated by using the testing data. Further, the testing results prove that the designed MR gun recoil long-stroke shock absorber's dynamic performance under impact load can be well controlled by changing the applied current, and the dynamic response models for MR gun recoil shock absorber under impact load are proved.
Hu, HS, Wang, J & Li, YC 2009, 'Design and magnetic analysis of a gun recoil magneto-rheological damper', Dandao Xuebao/Journal of Ballistics, vol. 21, no. 2, pp. 78-82.
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A gun recoil magneto-rheological (MR) damper under impact load was researched. A full-scale gun recoil MR damper with long-stroke, multistage slotted and smoothness disposal was designed. The coupling problem between structure and magnetic circuit for MR recoil damper was solved by the electromagnetic field finite element analysis software, and the electromagnetic field distribution of the designed gun recoil MR damper was also analyzed under different conditions, such as coil ringing direction, plunger and steel cylinder part's material selection, dampen channel, smoothness and chamfering disposal, etc. The magnetic circuit design rules of MR recoil damper under high impact load were also concluded. The simulation results indicate that the performance of the designed gun recoil damper satisfy the design requirements.
Husnawan, M, Masjuki, HH, Mahlia, TMI & Saifullah, MG 2009, 'Thermal analysis of cylinder head carbon deposits from single cylinder diesel engine fueled by palm oil–diesel fuel emulsions', Applied Energy, vol. 86, no. 10, pp. 2107-2113.
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Indraratna, B, Attya, A & Rujikiatkamjorn, C 2009, 'Experimental Investigation on Effectiveness of a Vertical Drain under Cyclic Loads', Journal of Geotechnical and Geoenvironmental Engineering, vol. 135, no. 6, pp. 835-839.
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Indraratna, B, Muttuvel, T & Khabbaz, H 2009, 'Modelling the erosion rate of chemically stabilized soil incorporating tensile force - deformation characteristics', CANADIAN GEOTECHNICAL JOURNAL, vol. 46, no. 1, pp. 57-68.
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To evaluate the safety of embankment dams, it is necessary to estimate the erosion rate based on common geotechnical properties such as shear and tensile strength. However, the empirical expressions that are currently available in the literature for this purpose are often inadequate. In this paper, an analytical model is developed to model the erosion of a soil capturing its tensile behaviour based on the law of energy conservation. The erosion rate can be determined using the proposed model if the tensile force - deformation characteristics, dry density, mean particle diameter, and mean flow velocity are known. The proposed model is semi-empirical and can be validated with experimental results obtained from the novel process simulation apparatus for internal crack erosion (PSAICE) designed and built at the University of Wollon- gong, Australia. All tests were conducted on erodible silty sand stabilized with cement and lignosulfonate. The model validation clearly indicates that only a fraction of the energy (efficiency index) from the water stream is effectively used for erosion. © 2009 NRC Canada.
Indraratna, B, Rujikiatkamjorn, C, Vinod, J & Khabbaz, H 2009, 'A Review of Ballast Characteristics, Geosynthetics, Confining Pressures and Native Vegetation in Rail Track Stabilisation', Transport Engineering in Australia, vol. 12, no. 1, pp. 25-36.
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Given the increased demand for freight transport for the mining and agriculture industries, and for greater public transport via trains due to increased fuel costs, heavier cyclic loading on existing tracks is now inevitable. Construction of rail tracks requires appropriate ballast specification to increase stability and performance of railway tracks. This paper aims to demonstrate and discuss some major aspects in relation to stabilisation of ballasted rail tracks overlying soft formation soils using geocomposites, prefabricated vertical drains and native vegetation. The use of geocomposites (ie. bonded geogrid-geotextile layers) for enhancing the performance of fresh and recycled ballast is described, with the aim of achieving reduced track settlement, increased resilient modulus and decreased ballast degradation. The effects of increasing the confi ning pressure on rail track behaviour, particularly with regard to particle breakage, have been studied using large-scale laboratory tests under cyclic loads. An elastoplastic stress-strain constitutive model for ballast was developed at the University of Wollongong, incorporating the degradation of particles as a particular feature, was introduced by capturing the breakage of particles during shearing, and the effects of cyclic loading on particle degradation and plastic deformation. In addition, numerical simulation using discrete element method has been carried out an assembly of irregular particles to investigate the mechanism of ballast breakage and to quantify breakage in relation to the ballast particle size distribution.
INDRARATNA, B, VINOD, JS & LACKENBY, J 2009, 'Influence of particle breakage on the resilient modulus of railway ballast', Géotechnique, vol. 59, no. 7, pp. 643-646.
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Numerous research studies have been carried out in the recent past to determine the influence on the resilient modulus of railway ballast of parameters such as stress history, number of loading cycles, density, grading, fines content, maximum grain size, aggregate type, particle shape and moisture content. However, the influence of particle breakage on the resilient modulus has not been described in depth. The current study highlights the influence of particle breakage on the resilient modulus of latite ballast (commonly used in railway track in New South Wales, Australia). Aggregate degradation is represented by the ballast breakage index (BBI). Laboratory test results indicate that the BBI has a profound influence on the resilient modulus of ballast. The resilient modulus increases with BBI, irrespective of the effective confining pressure. In addition, a simple hyperbolic relationship has been proposed between the resilient modulus MR and the bulk stress φ for latite ballast.
Jahirul, MI, Saidur, R, Masjuki, HH, Kalam, MA & Rashid, MM 2009, 'Application of Artificial Neural Networks (ANN) for Prediction the Performance of a Dual Fuel Internal Combustion Engine', HKIE Transactions, vol. 16, no. 1, pp. 14-20.
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Jayed, MH, Masjuki, HH, Saidur, R, Kalam, MA & Jahirul, MI 2009, 'Environmental aspects and challenges of oilseed produced biodiesel in Southeast Asia', Renewable and Sustainable Energy Reviews, vol. 13, no. 9, pp. 2452-2462.
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Johir, AH, Khorshed, C, Vigneswaran, S & Shon, HK 2009, 'In-line flocculation-filtration as pre-treatment to reverse osmosis desalination', DESALINATION, vol. 247, no. 1-3, pp. 85-93.
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In this paper the performance of single and dual media filters with in-line flocculation have been examined as pretreatment to seawater reverse osmosis (SWRO). A comparison of filter performance was made between single medium filter (80 cm) consisting of sand or anthracite, and dual media filter consisting of sand (40 cm at the bottom) and anthracite (40 cm on top). Short term (6 hours) experiments were conducted with in-line coagulation followed by direct filtration. Filtration velocities of 5 m/h and 10 m/h were used. The performances of these filters were assessed in terms of turbidity removal, head loss build-up, and organic compound removal in terms of molecular weight distribution (MWD). The efficiency of the filter as pretreatment was evaluated in terms of silt density index (SDI) and modified fouling index (MFI). It was found that the turbidity removal was high and all the filters produced more or less same quality water. There was a slower buildup of head loss for coarser filter medium. A post treatment of reverse osmosis after an inline-flocculation-dual media filtration showed lower normalized flux decline (J/J0) (0.35 to 0.22 during the first 20 hours operation) while, seawater without any pretreatment showed steeper flux decline (0.18 to 0.11 at first 20 hours operation) in RO.
Johir, MAH, Lee, JJ, Vigneswaran, S, Kandasamy, J & Shaw, K 2009, 'Treatment of Stormwater using Fibre Filter Media', Water, Air, & Soil Pollution: Focus, vol. 9, no. 5-6, pp. 439-447.
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In this study, a high-rate fibre filter was used as a pre-treatment to stormwater in conjunction with in-line flocculation. The effect of operating the fibre filter with different packing densities (105, 115 and 125 kg/m3) and filtration velocities (20, 40, 60 m/h) with and without in-line flocculation was investigated. In-line flocculation was provided using 5, 10 and 15 mg/L of ferric chloride (FeCl3·6H2O). The filter performance was studied in terms of pressure drop (ÎP), solids removal efficiency, heavy metals (total) removal efficiency and total organic carbon (TOC) removal efficiency. It is found that the use of in-line flocculation at a dose of 15 mg/L improved the performance of fibre filter as measured by turbidity removal (95%), total suspended solids reduction (98%), colour removal efficiency (99%), TOC removal (reduced by 30â40 %) and total coliform removal (93%). The modified fouling index reduced from 750â950 to 12 s/L2 proving that fibre filter can be an excellent pre-treatment to membrane filtration that may be consider as post-treatment. The removal efficiency of heavy metal was variable as their concentration in raw water was small. Even though the concentration of some of these metals such as iron, aluminium, copper and zinc were reduced, others like nickel, chromium and cadmium showed lower removal rates
Johir, MAH, Vigneswaran, S & Kandasamy, J 2009, 'Deep bed filter as pre-treatment to stormwater', Desalination and Water Treatment, vol. 12, no. 1-3, pp. 313-323.
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This paper presents the results of experiments on the application of dual media and single media deep bed filters as pre-treatments to stormwater. In-line flocculation-filtration experiments were conducted with dual and single media filter. The single filter media (80 cm) consisted of either anthracite or sand, and the dual media filter consisted of sand (40 cm at the bottom) and anthracite (40 cm on top). Filtration velocities of 5 m/h, 10 m/h and 15 m/h were examined. The removal efficiency for turbidity, suspended solids and TOC was found to be 95%, 99% and 30â45% respectively at a flocculant dose of FeCl3 of 15 mg/L. The anthracite filter media showed a lower headloss development (26 cm, operated at 5 m/h filtration velocity with FeCl3 dose of 5 mg/L). The removal efficiency for nitrogen was lower than phosphorus which was relatively good (up to 50%). The removal efficiency for heavy metals such as Cd, Pb, Cr and Ni was found to be very low for all tested filtration systems because concentrations of these metals in the influent were also low. This filter can be used as a pretreatment to a membrane filter as the modified fouling index was reduced from 750 s/L2 (for stormwater) to 15 s/L2 (for filtered effluent). Detailed submerged membrane filter experiments conducted with pre-treated water showed that the membrane filter can be successfully be used as post-treatment to in-line flocculant-filter at a sustainable flux of 10 L/m2.h to remove the remaining solids and pathogens. An increase of air scouring in the membrane unit decreased the pressure development although it did not have any effect on increasing the critical flux beyond 10 L/m2.h.
Jones, J, Wu, C, Oehlers, DJ, Whittaker, AS, Sun, W, Marks, S & Coppola, R 2009, 'Finite difference analysis of simply supported RC slabs for blast loadings', Engineering Structures, vol. 31, no. 12, pp. 2825-2832.
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Kalam, MA, Masjuki, HH, Redzuan, M, Mahlia, TMI, Fuad, MA, Mohibah, M, Halim, KH, Ishak, A, Khair, M, Shahrir, A & Yusoff, A 2009, 'Development and test of a new catalytic converter for natural gas fuelled engine', Sadhana, vol. 34, no. 3, pp. 467-481.
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Kus, B & Kandasamy, J 2009, 'Low-Cost Filtration System to Treat First-Flush Stormwater', Water, Air, & Soil Pollution: Focus, vol. 9, no. 5-6, pp. 347-355.
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The aim of this paper is to evaluate the performance of the low-flow filtration system (LFFS) that Kogarah Municipal Council developed for treating and reusing the highly polluted first-flush stormwater (FFSW) while allowing the cleaner subsequent major stormwater flows to be directed to the major street drainage. The LFFS was evaluated through laboratory investigations using columns packed with different filter media to test the removal efficiency of pollutants such as zinc (Zn), total phosphorus (TP), total nitrogen (TN), total organic content, total petroleum hydrocarbons (TPH), and turbidity. The findings from this study demonstrate the effectiveness of the LFFS to largely reduce turbidity, TPH, and trace metals from the FFSW. The LFFS also partially removes dissolved organics, TP and TN. These pollutants are more commonly and effectively removed in subsequent processes of a stormwater treatment train. Further this paper highlights the importance of regular maintenance of the LFFS especially as it is only associated in removing the high pollutant loads during a storm event. Due to this first flush, a thick oily crust-formed layer requires monthly removal, and an entire replacement of the exhausted filter media is required quarterly. However considering the labor required to service the crust formed layer within the LFFS, it is more cost effective to replace the entire depth of filter media monthly.
Lawrence, SJ & Stewart, MG 2009, 'Reliability-Based Calibration of the Capacity Reduction Factor for Design of Masonry in Compression to AS3700', Australian Journal of Structural Engineering, vol. 9, no. 2, pp. 97-110.
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The paper examines the reliability of masonry walls designed for compression in accordance with AS3700. The results of a large number of tests on full-scale masonry walls in compression have been used to obtain probabilistic models of behaviour. Structural reliability was then estimated for vertical loading of unreinforced masonry walls loaded concentrically, considering variations of unit compressive strength, mortar type, tributary area and live-to-dead load ratios. A reliability-based calibration of the Australian masonry design code AS3700 was then conducted using a target reliability index specified in AS5104. Recommendations are made for changes to $ used for compression design in AS3700 that, if adopted, would lead to an increase of 66% in the design compressive strength of walls. © Institution of Engineers Australia, 2009.
Lee, BC, Kim, S, Shon, HK, Vigneswaran, S, Kim, SD, Cho, J, Kim, IS, Choi, KH, Kim, JB, Park, HJ & Kim, J-H 2009, 'Aquatic toxicity evaluation of TiO2 nanoparticle produced from sludge of TiCl4 flocculation of wastewater and seawater', JOURNAL OF NANOPARTICLE RESEARCH, vol. 11, no. 8, pp. 2087-2096.
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Flocculation using titanium tetrachloride (TiCl4) as a coagulant is an efficient and economical application because the flocculated sludge can be recycled to produce a valuable byproduct, namely titanium dioxide (TiO2) nanoparticles. However, toxicity of TiCl4 has not yet been assessed while it is used in water treatment. The aquatic toxicity of TiCl4 flocculation process was investigated to assess the environmental safety of the coagulant. D. magna and V. fischeri bioassays were carried out to evaluate the supernatant toxicity after TiCl4 flocculation. Artificial wastewater, biologically treated sewage effluent, and seawater were used to study the toxicity of TiCl4 flocculation. Results showed that supernatant toxicity was very low when TiCl4 flocculation was conducted (no observed effect concentration = 100 mg/L and lowest observed effect concentration = 150 mg/L exposed to D. magna and V. fischeri, respectively). Similarly, TiO2 nanoparticles recovered from wastewater and seawater flocculated sludge were also found to have low toxicity. The regenerated TiO2 nanoparticles indicated low toxicity values when compared to the commercial-TiO2 nanoparticle, P-25.
Lee, JJ, Johir, MAH, Chinu, KH, Shon, HK, Vigneswaran, S, Kandasamy, J, Kim, CW & Shaw, K 2009, 'Hybrid filtration method for pre-treatment of seawater reverse osmosis (SWRO)', DESALINATION, vol. 247, no. 1-3, pp. 15-24.
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Hybrid processes combining fi bre fi lter with deep bed fi ltration process such as (i) fi bre fi lter and sand fi lter, (ii) fi bre fi lter and anthracite and (iii) fi bre fi lter and dual media fi lter were investigated as pre- treatments to SWRO. Seawater was drawn from Chowder Bay, Sydney. The eff ect of diff erent pretreatment hybrid systems was investigated in terms of silt density index (SDI10), modifi ed fouling index (MFI), headloss across the fi lters and reduction in turbidity and dissolved organic carbon (DOC). The in-line fl occulation in fi bre fi lter improved the performance of the pretreatment hybrid system as measured by the MFI, SDI10, headloss, turbidity and DOC removal. The lowest SDI10 and MFI were found with a fi bre fi lter operated at a fi ltration velocity of 40 m/h followed by dual media fi lter operated at a fi ltration velocity of 5 m/h. The lowest headloss and turbidity was found with a fi bre fi lter operated at a fi ltration velocity of 40 m/hr followed by anthracite operated at a fi ltration velocity of 5 m/h. This system also gave an effl uent with the lowest DOC of 0.64 mg/L corresponding to a removal effi ciency of about 70%.
Li, Y, Li, J, Samali, B & Wang, J 2009, 'Design considerations and experimental studies on semi-active smart pin joint', Frontiers of Mechanical Engineering in China, vol. 4, no. 4, pp. 363-370.
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Hostile dynamic loadings such as severe wind storms, earthquakes, and sudden impacts can cause severe damage to many civil engineering structures. An intelligent structural system equipped with smart structural members that are controllable in real-time is an effective solution to structural damage and failure during such situations. Civil intelligent structures with controllable properties to adapt to any changes due to dynamic loadings can lead to effective protection of structures and their occupants. In this paper, design and testing of a semi-active magnetorheological (MR) pin joint, in which the moment resistance can be controlled in real-time by altering the magnetic field, is reported with the view of using it as a potential candidate for smart members in the development of intelligent structures. Design of prototype smart pin joints includes theoretical analysis related to the radius of the rotary plate, the property of MR fluids and the gap between the rotary plate and the casing based on the requirements of the dynamics of MR pin joints. FEM analysis was deployed to study the distribution of the magnetic field along the gap. It is found, from the theoretical analysis and experimental verification, that the MR pin joint with a diameter of 180 mm can produce a torque of up to 30 Nm, which meets requirements for semi-active members in a multi-storey prototype building model in the next stage of research and development. © Higher Education Press and Springer-Verlag 2009.
Listowski, A, Ngo, HH, Guo, WS, Vigneswaran, S & Palmer, CG 2009, 'Concepts towards a novel integrated assessment methodology of urban water reuse', DESALINATION AND WATER TREATMENT, vol. 11, no. 1-3, pp. 81-92.
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Traditional supplies of large volumes of water and wastewater disposal technologies have offered a linear solution, thus intensifying environmental stress. In addition, provision of urban infrastructure especially any major augmentations are often the impractical or economically prohibitive. Urban water cycle should be viewed as an interactive and coordinated approach involving: Available water resources, Appropriate treatment technology producing fi t for purpose water quality, and Ascertaining long term balance between environmental, social and economic issues.
LIU, S-G, NI, B-J, WEl, L, TANG, Y & YU, H-Q 2009, 'Contact-Adsorption-Regeneration-Stabilization Process for the Treatment of Municipal Wastewater', Journal of Water and Environment Technology, vol. 7, no. 2, pp. 83-90.
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Liu, X-W, Yu, H-Q, Ni, B-J & Sheng, G-P 2009, 'Characterization, Modeling and Application of Aerobic Granular Sludge for Wastewater Treatment', BIOTECHNOLOGY IN CHINA I, vol. 113, pp. 275-303.
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Mahmoud, A, Shendi, M, Pradhan, B & Attia, F 2009, 'Utilization of remote sensing data and GIS tools for and use sustainability analysis: case study in El-Hammam area, Egypt', Open Geosciences, vol. 1, no. 3, pp. 347-367.
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Abstract The North-Western Coast of Egypt (NWCE) represents one of the high priority regions for future development in the country. El-Hammam area is located in the NWCE with an area of 94752 acres and is one of the main challenging regions for sustaianble development. In this study, we have used remote sensing and soil data in combination with GIS tools, for land use sustainable analysis (SLU) in El-Hammam area. The SLU was established based on various factors such as: land capability and suitability, water resources availability, economic return from water and financial return from land and water. A physiographic soil map for the study area was prepared using remote sensing and GIS. Multiple field surveys were carried out for collecting information on various soil map units (SMUs) and their profiles. Laboratory analysis for the collected samples was performed, and then the soil properties were stored as attributes in a geographical soil database linked with the SMUs. Furthermore, land capability assessment was done to define the suitable areas for agricultural production using a capability model built in ALES software. Results indicate that the area currently lacks high capability and moderate capability classes. By improving the soil properties, the soil can attain potential capability; and 55630 acres will become marginally capable. The assessment of soil physical suitability for different land use types (LUTs) were analysed in ALES software, in order to generate the most suitable areas. The results from the land suitability analysis indicated that, 17114 acres are moderately suitable for wheat and sorghum; whereas 15823 acres are moderately suitable for barley and 12752 acres are moderately suitable for maize, olive and figs. Finally, the SLU was investigated based on two scenarios; (1) the most SLU under the conditions of shortage of irrigation water: clover, barley and sorghum against figs, as the i...
Mullard, JA & Stewart, MG 2009, 'Stochastic Assessment of Timing and Efficiency of Maintenance for Corroding RC Structures', Journal of Structural Engineering, vol. 135, no. 8, pp. 887-895.
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Reinforced concrete (RC) structures in a chloride environment are exposed to a particularly aggressive form of deterioration. Managing the maintenance and repair of structures subjected to these conditions is an important issue facing asset owners and operators. In the present paper, the criterion for repair is the extent of corrosion induced cracking. Common maintenance criteria and maintenance techniques are described and these are incorporated into a two-dimensional spatial time-dependent reliability model. This allows the number, timing, and extent of maintenance actions to be predicted over the service life of RC structures. The analysis includes the effect of inspection interval, maintenance technique, repair efficiency, and repair threshold. Results are presented for a typical RC bridge deck subject to a corrosive marine environment. It was found that repair efficiency affecting time to corrosion initiation of repaired concrete is more critical to the performance of the repair than the repair efficiency that affected corrosion rate. © 2009 ASCE.
Nazem, M, Carter, JP, Sheng, D & Sloan, SW 2009, 'Alternative stress-integration schemes for large-deformation problems of solid mechanics', Finite Elements in Analysis and Design, vol. 45, no. 12, pp. 934-943.
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Netherton, MD & Stewart, MG 2009, 'Probabilistic modelling of safety and damage blast risks for window glazingThis paper is one of a selection of papers in the Special Issue on Blast Engineering.', Canadian Journal of Civil Engineering, vol. 36, no. 8, pp. 1321-1331.
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There are many computational techniques to model the consequences to built infrastructure when subject to explosive blast loads; however, the majority of these do not account for the uncertainties associated with system response or blast loading. This paper describes a new computational model, called “Blast-RF” (Blast Risks for Facades), that incorporates existing (deterministic) blast-response models within an environment that considers threat and (or) vulnerability uncertainties and variability using probability and structural reliability theory. The structural reliability analysis uses stress limit states and the UK Glazing Hazard Guide's rating criteria to calculate probabilities of glazing damage and occupant safety hazards conditional on a given blast scenario. This allows the prediction of likelihood and extent of damage and (or) casualties, useful information for risk mitigation considerations, emergency service's contingency and response planning, collateral damage estimation, weaponeering, and post-blast forensic analysis.
Netherton, MD & Stewart, MG 2009, 'The effects of explosive blast load variability on safety hazard and damage risks for monolithic window glazing', International Journal of Impact Engineering, vol. 36, no. 12, pp. 1346-1354.
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Although the modelling of built infrastructure subject to blast loading has been well developed, considerable uncertainty remains with respect to explosive loading parameters and structural response. This paper focuses on facade glazing - as this poses significant safety hazards when affected by explosive blast loads. A structural reliability analysis is used to calculate probabilities of glazing damage and safety hazards conditional on given threat scenarios. The analysis considers the variability of explosive blast loading; in particular, from variations in explosive weight, explosion effects in terms of pressure, stand-off distance, inherent blast load variability and model error. Uncertainties in structural response (including the variability in glazing stress limits, situational geometry, fragment drag coefficients and modelling error) are then considered in the analysis. This allows the prediction of likelihood and extent of damage and casualties. It was found that damage and safety hazard risks are very sensitive to the accuracy of the blast loading prediction model and the inherent variability of blast loading. © 2009 Elsevier Ltd. All rights reserved.
Ngo, H-H & Guo, W 2009, 'Membrane fouling control and enhanced phosphorus removal in an aerated submerged membrane bioreactor using modified green bioflocculant', BIORESOURCE TECHNOLOGY, vol. 100, no. 18, pp. 4289-4291.
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This study aims at developing a modified green bioflocculant (GBF) for membrane fouling control and enhanced phosphorus removal in a conventional aerated submerged membrane bioreactor (SMBR) to treat a high strength domestic wastewater (primary sewage treated effluent) for reuse. The GBF was evaluated based on long-term operation of a lab-scale SMBR. These results showed that SMBR system could achieve nearly zero membrane fouling at a very low dose of GBF addition (500 mg/day) with less backwash frequency (2 times/day with 2-min duration). The transmembrane pressure only increased by 2.5 kPa after 70 days of operation. The SMBR could also remove more than 95% and 99.5% dissolved organic carbon and total phosphorus, respectively. From the respiration tests, it was evident that GBF not only had no negative impact on biomass but also led to high oxygen uptake rate (OUR) (>30 mg O2/L h) and stable specific oxygen uptake rate (SOUR). These results also indicated that GBF had no effect on nitrogen removal and nitrification process.
Ngo, HH, Chuang, H, Guo, WS, Ho, DP, Pham, TTN, Johnston, A, Lim, R & Listowski, A 2009, 'Resident's strategy survey on a new end use of recycled water in Australia', DESALINATION AND WATER TREATMENT, vol. 11, no. 1-3, pp. 93-97.
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The concept of using recycled water for washing machine was introduced as a new end use. As there is a noticeable lack social research in understanding the general public perceptions of this application, the resident's strategy survey was carried out at some selective suburbs in Sydney with demographically based significant differences of general, gender, age, education, and property style and ownership. The survey indicates that the majority in the community considers the use of recycled water for washing machine is indispensable in view of continuing drought and the associated water shortages. Given safety assurance and demonstration, recycled water for washing machine has a considerable proportion within the responses. The general level of knowledge in community clearly understand that recycled water is more environmentally friendly option, whereas from cleanness and public health point of view, higher quality water is required to be reused in washing machine. Moreover, the residents reckon to have a small unit for pre-treatment (point of use) before recycled water entering washing machines might assure the quality and safety. The survey also shows the major concerns for a resident to use recycled water for washing machine are public health, water cleanness and washing machine durability. © 2009 Desalination Publications.
Nguyen, TV, Nguyen, TVT, Pham, TL, Vigneswaran, S, Ngo, HH, Kandasamy, J, Nguyen, HK & Nguyen, DT 2009, 'Adsorption and removal of arsenic from water by iron ore mining waste', Water Science and Technology, vol. 60, no. 9, pp. 2301-2308.
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There is a global need to develop low-cost technologies to remove arsenic from water for individual household water supply. In this study, a purified and enriched waste material (treated magnetite waste, TMW) from the Trai Cau's iron ore mine in the Thai Nguyen Province in Vietnam was examined for its capacity to remove arsenic. The treatment system was packed with TMW that consisted of 75% of ferrous-ferric oxide (Fe3O4) and had a large surface area of 89.7 m2/g. The experiments were conducted at a filtration rate of 0.05 m/h to treat groundwater with an arsenic concentration of 380 μg/L and iron, manganese and phosphate concentrations of 2.07 mg/L, 0.093 mg/L and 1.6 mg/L respectively. The batch experimental results show that this new material was able to absorb up to 0.74 mg arsenic/g. The results also indicated that the treatment system removed more than 90% arsenic giving an effluent with an arsenic concentration of less than 30 μg/L while achieving a removal efficiency of about 80% for Mn2 + and PO43−. This could be a promising and cost-effective new material for capturing arsenic as well as other metals from groundwater.
Nguyen, TV, Rahman, A, Vigneswaran, S, Ngo, HH, Kandasamy, J, Nguyen, DT, Do, TA & Nguyen, TK 2009, 'Arsenic removal by iron oxide coated sponge: treatment and waste management', WATER SCIENCE AND TECHNOLOGY, vol. 60, no. 6, pp. 1489-1495.
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One of the problems in drinking water that raises concern over the world is that millions of people still have to use arsenic-contaminated water. There is a worldwide need to develop appropriate technologies to remove arsenic from water for household and community water supply systems. In this study, a new material namely iron oxide coated sponge (IOCSp) was developed and used to remove arsenic (As) from contaminated groundwater in Vietnam. The results indicated that lOCSp has a high capacity in removing both As (V) and As (III). The adsorption capacity of IOCSp was up to 4.6 mg As/g IOCSp, showing better than many other materials. It was observed from a pilot study that a small quantity of IOCSp (180 g) could reduce As concentration of 480 μg/L in 1.5 m3 of contaminated natural water to below 40 μg/L. In addition, an exhausted IOCSp, containing a large amount of arsenic (up to 0.42 wt %) could safely be disposed through the solidification/stabilization with cement. Addition of fly ash also reduced the amount of arsenic in the leachate. © IWA Publishing 2009.
Nguyen, VT, Vigneswaran, S, Ngo, HH, Shon, HK & Kandasamy, J 2009, 'Arsenic removal by a membrane hybrid filtration system', DESALINATION, vol. 236, no. 1-3, pp. 363-369.
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Arsenic is a toxic semi-metallic element that can be fatal to human health. Membrane filtration can remove a number of contaminants from water, including arsenic. Removal of arsenic by membrane filtration is highly dependent on the species of arsenic and the properties of the membrane. The performance of the nanofilter is better for removing As(V) than As(III). About 57% of As(III) and 81% of As(V) was removed from 500 mg/L arsenic solutions by nanofiltration (NTR729HF, Nitto Denko Corp., Japan) of 700 molecular weight (MW) cutoff. The removal efficiency of microfiltration (MF) was much lower than that of nanofiltration (NF) due to its larger pore size. By comparison only 37% of As(III) and 40% of As(V) were removed by microfiltration (PVA membrane, Pure-Envitech, Korea). However, the removal efficiency of microfiltration was increased dramatically when a small amount of nanoscale zero valent iron (nZVI) was added. The removal efficiency by MF increased up to 90% with As(V) and 84% with As(III) when an amount of 0.1 g/L of nZVI was added into the arsenic solution.
Ni, B & Yu, H 2009, 'A thermodynamic analysis of the activated sludge process: Application to soybean wastewater treatment in a sequencing batch reactor', AIChE Journal, vol. 55, no. 10, pp. 2737-2745.
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AbstractA bioenergetic methodology was integrated with a modified activated sludge model No.1 (ASM1) to analyze the activated sludge process, with the treatment of soybean‐processing wastewater as an example. With the bioenergetic methodology established by McCarty and coworkers, the microbial yield was predicted and the overall stoichiometrics for biological reactions involving the key chemical and biological species in activated sludge were established. These obtained parameters were related to the ASM1 model, which was modified after coupling the biological reactions in activated sludge with electron balances. This approach was able to approximately describe the treatment of soybean wastewater by activated sludge in a sequencing batch reactor in terms of substrate utilization, biomass growth, and the elector acceptor consumption. Such an attempt provides useful information for accurate modeling of the complex activated sludge process. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Ni, B, Chen, Y, Liu, S, Fang, F, Xie, W & Yu, H 2009, 'Modeling a granule‐based anaerobic ammonium oxidizing (ANAMMOX) process', Biotechnology and Bioengineering, vol. 103, no. 3, pp. 490-499.
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AbstractA mathematical model was developed to describe the anaerobic ammonium oxidation (ANAMMOX) process in a granular upflow anaerobic sludge blanket (UASB) reactor. ANAMMOX granules were cultivated in the UASB reactor by seeding aerobic granules. The granule‐based reactor had a great N‐loading resistant capacity. The model simulation results on the 1‐year reactor performance matched the experimental data well. The yield coefficient for the growth and the decay rate coefficient of the ANAMMOX granules were estimated to be 0.164 g COD g−1 N and 0.00016 h−1, respectively. With this model, the effects of process parameters on the reactor performance were evaluated. Results showed that the optimum granule diameter for the maximum N‐removal should be between 1.0 and 1.3 mm and that the optimum N loading rate should be 0.8 kg N m−3 d−1. In addition, the substrate micro‐profiles in the ANAMMOX granules were measured with a microelectrode to explore the diffusion dynamics within the granules, and the measured profiles matched the predicted results well. Biotechnol. Bioeng. 2009;103: 490–499. © 2009 Wiley Periodicals, Inc.
Ni, B, Xie, W, Liu, S, Yu, H, Wang, Y, Gan‐Wang & Dai, X 2009, 'Modeling and simulation of the sequencing batch reactor at a full‐scale municipal wastewater treatment plant', AIChE Journal, vol. 55, no. 8, pp. 2186-2196.
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AbstractIn this work, we attempted to modify the Activated Sludge Model No.3 and to simulate the performance of a full‐scale sequencing batch reactor (SBR) plant for municipal wastewater treatment. The long‐term dynamic data from the continuous operation of this SBR plant were simulated. The influent wastewater composition was characterized using batch measurements. After incorporating all the relevant processes, the sensitivity of the stoichiometric and kinetic coefficients for the model was thoroughly analyzed prior to the model calibration. The modified model was calibrated and validated with the data from both batch‐ and full‐scale experiments. Model predictions were compared with routine data in terms of chemical oxygen demand, NH4+‐N and mixed liquid volatile suspended solids in the SBR, combined with batch experimental data under different conditions. The model predictions match the experimental results well, demonstrating that the model is appropriate to simulate the performance of a full‐scale wastewater treatment plant even operated under perturbation conditions. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Ni, B-J, Fang, F, Rittmann, BE & Yu, H-Q 2009, 'Modeling Microbial Products in Activated Sludge under Feast−Famine Conditions', Environmental Science & Technology, vol. 43, no. 7, pp. 2489-2497.
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Ni, B-J, Fang, F, Xie, W-M, Sun, M, Sheng, G-P, Li, W-H & Yu, H-Q 2009, 'Characterization of extracellular polymeric substances produced by mixed microorganisms in activated sludge with gel-permeating chromatography, excitation–emission matrix fluorescence spectroscopy measurement and kinetic modeling', Water Research, vol. 43, no. 5, pp. 1350-1358.
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Ni, B-J, Xie, W-M, Liu, S-G, Yu, H-Q, Wang, Y-Z, Wang, G & Dai, X-L 2009, 'Granulation of activated sludge in a pilot-scale sequencing batch reactor for the treatment of low-strength municipal wastewater', Water Research, vol. 43, no. 3, pp. 751-761.
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Ni, B-J, Zeng, RJ, Fang, F, Xu, J, Sheng, G-P & Yu, H-Q 2009, 'A Novel Approach to Evaluate the Production Kinetics of Extracellular Polymeric Substances (EPS) by Activated Sludge Using Weighted Nonlinear Least-Squares Analysis', Environmental Science & Technology, vol. 43, no. 10, pp. 3743-3750.
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Nisola, GM, Cho, ES, Shon, HK, Tian, D, Chun, DJ, Gwon, EM & Chung, WJ 2009, 'Cell Immobilized FOG-Trap System for Fat, Oil, and Grease Removal from Restaurant Wastewater', Journal of Environmental Engineering, vol. 135, no. 9, pp. 876-884.
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Cell immobilized lipase-producing bacteria on three different matrices were incorporated in a fat-, oil-, and grease (FOG) trap system for restaurant wastewater treatment. During a 16-day laboratory-scale experiment for the treatment of synthetic FOG wastewater containing soybean oil, no significant difference (two-tailed t test at 95% confidence interval) in the FOG removal between two systems was observed at FOG influent < 1,000 mg/L. However, the typical trap showed lower FOG removal efficiency than the matrix-based system when the influent FOG concentration was increased to >= 5,000 mg/L. In addition, the matrix-based trap system was able to sustain a stable high FOG removal, with < 100 mg/L effluent, even at 10,000 mg/L influent FOG. Based on FOG heights measured and mass balance calculations, 97.4 and 99.5% of the total FOG load for 16 days were removed in a typical trap and matrix-based system, respectively. About 93.6% of the removal in the matrix-based was accounted to biodegradation. The 30-day full-scale operations demonstrated a distinguishably better performance in the matrix-based system (92.7 +/- 9.06% of 1,044.8 +/- 537.27 mg FOG/L) than in the typical trap system (74.6 +/- 27.13% of 463.4 +/- 296.87 mg FOG/L) for the treatment of barbeque restaurant wastewater. Similarly, matrix-based system revealed higher chemical oxygen demand removal (85.9 +/- 11.99%) than the typical trap system (60.4 +/- 31.26%). Characterizations of the influent, emulsified, adsorbed and effluent FOG indicated that straight saturated fatty acids constituted the cause of clogging problems in the FOG-trap and piping system.
Okour, Y, El Saliby, I, Shon, HK, Vigneswaran, S, Kim, J-H, Cho, J & Kim, IS 2009, 'Recovery of sludge produced from Ti-salt flocculation as pretreatment to seawater reverse osmosis', DESALINATION, vol. 247, no. 1-3, pp. 53-63.
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In this study, titanium tetrachloride (TiCl4), titanium sulfate (Ti(SO4)2) and ferric chloride (FeCl3) flocculation as a pretreatment to seawater reverse osmosis (SWRO) were investigated. Their ability to remove turbidity, seawater organic matter (SWOM) and controlling the feed water quality of SWRO was evaluated. Flux decline of SWRO and membrane autopsy were studied. Titanium dioxide (TiO2) produced from sludge after Ti-salt fl occulation was characterized in terms of particle structure and photocatalytic activity. A hybrid system of fl occulation followed by granular activated carbon (GAC) filtration was employed to remove the suspended micro-flocs after diff erent fl occulations. The optimum dose of 10 mg/L TiCl4 and FeCl3 were used. The turbidity removal for the three coagulants was marginal at different doses at pH 6 and 8. Flocculation followed by GAC fi ltration signifi cantly reduced the turbidity values from 1.5 NTU to about 0.35 NTU using TiCl4 and 0.40 using FeCl3. Silt density index (SDI15) was also decreased from 5.0 to 4.2 and 4.7, respectively. Removal of dissolved organic carbon (DOC), colour and UV absorbance after TiCl4 and FeCl3 flocculation followed by GAC fi ltration was found to be eff ective and similar. TiO2 produced from sludge showed very high photocatalytic activity under UV-irradiation. Acetaldehyde was completely removed after 45 min photocatalytic reaction
Okour, Y, Shon, HK & El Saliby, I 2009, 'Characterisation of titanium tetrachloride and titanium sulfate flocculation in wastewater treatment', WATER SCIENCE AND TECHNOLOGY, vol. 59, no. 12, pp. 2463-2473.
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Flocculation with titanium tetrachloride (TiCl4) and titanium sulfate (Ti(SO4)2) was investigated in terms of different coagulant doses, pH, turbidity, dissolved organic carbon (DOC), UV-254, colour, zeta potential, particle size and molecular weight distribution. The two coagulants were compared with the commonly used coagulants such as ferric chloride (FeCl3) and aluminium sulfate (Al2(SO4)3). Titanium tetrachloride showed the highest turbidity removal, while titanium sulfate showed the highest reduction of UV-254 and colour at all pH values. The four coagulants were found to have similar organic removal up to 6067% and resulted in similar organic removal in terms of various MW ranges. The decantability of the settled flocs was very high for titanium tetrachloride, titanium sulfate and ferric chloride compared with aluminium sulfate. The dominating coagulation mechanisms for titanium tetrachloride and titanium sulfate are still to be studied, since different precipitation reactions might take place at different pH even without flocculant addition. Titanium tetrachloride and titanium sulfate were found as effective new coagulants in wastewater treatment not only in terms of organic matter removal, but also in sludge reduction through the production of titanium dioxide.
Oliveira, DAF, Indraratna, B & Nemcik, J 2009, 'Critical review on shear strength models for soil-infilled joints', Geomechanics and Geoengineering, vol. 4, no. 3, pp. 237-244.
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An infilled rock joint is likely to be the weakest plane in a rock mass. The presence of infill material within the joint significantly reduces the friction of the discontinuity boundaries (i.e. rock to rock contact of the joint walls). The thicker the infill, the smaller the shear strength of the rock joint. Once the infill reaches a critical thickness, the infill material governs the overall shear strength, and the joint walls (rock) play no significant role. Several models have been proposed to predict the peak shear strength of soil-infilled joints under both constant normal load (CNL) and constant normal stiffness (CNS) boundary conditions, taking into account the ratio of infill thickness (t) to the height of the joint wall asperity (a). CNS models provide a more realistic picture of the soil-infilled joint behaviour in the field. This paper presents a critical review on the existing mathematical models for predicting the shear strength of soil-infilled rock joint and verifies the normalised peak shear stress model with further laboratory investigations carried out on idealised saw-tooth rock joints at the University of Wollongong. Based on the prediction of the experimental data, the normalised peak shear stress model is slightly modified by the authors. A simplified approach for using this model in practice is presented and a new expression for prediction of dilatation at peak shear stress is suggested.
Pedroso, DM, Sheng, D & Zhao, J 2009, 'The concept of reference curves for constitutive modelling in soil mechanics', Computers and Geotechnics, vol. 36, no. 1-2, pp. 149-165.
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Pezzaniti, D, Beecham, S & Kandasamy, J 2009, 'Influence of clogging on the effective life of permeable pavements', Proceedings of the Institution of Civil Engineers - Water Management, vol. 162, no. 3, pp. 211-220.
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This paper investigates the ‘effective life’ (or useful lifespan) of permeable pavement installations subject to sediment loadings. The broad aims of this study, which included both laboratory and field work components, were to improve understanding of the long-term pavement hydraulic conductivity, to assess the effective life of permeable pavements and to quantify the degree of sediment trapping and associated pollutant retention. Three types of permeable pavement were investigated. For each type the effects of pavement cleaning were also investigated. Over a simulated 35 years of sediment loading conducted in the laboratory, the results showed reductions of 59–75% in hydraulic conductivity with an average sediment retention of 94%. Suspended sediment concentrations measured at the outflow of the laboratory test beds did not show any significant difference between pavers that were subjected to cleaning and those that were not. For the field studies presented in this paper, hydraulic conductivities were very high in locations where permeable pavements are subjected to small to moderate sediment loads. At other locations with high coarse sediment and organic sediment loads, hydraulic conductivity tests indicated that clogging occurred at a rapid rate, particularly where runoff flowing onto the pavement was concentrated.
Pradhan, B 2009, 'Groundwater potential zonation for basaltic watersheds using satellite remote sensing data and GIS techniques', Open Geosciences, vol. 1, no. 1, pp. 120-129.
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AbstractThis paper summarizes the findings of groundwater potential zonation mapping at the Bharangi River basin, Thane district, Maharastra, India, using Satty’s Analytical Hierarchal Process model with the aid of GIS tools and remote sensing data. To meet the objectives, remotely sensed data were used in extracting lineaments, faults and drainage pattern which influence the groundwater sources to the aquifer. The digitally processed satellite images were subsequently combined in a GIS with ancillary data such as topographical (slope, drainage), geological (litho types and lineaments), hydrogeomorphology and constructed into a spatial database using GIS and image processing tools. In this study, six thematic layers were used for groundwater potential analysis. Each thematic layer’s weight was determined, and groundwater potential indices were calculated using groundwater conditions. The present study has demonstrated the capabilities of remote sensing and GIS techniques in the demarcation of different groundwater potential zones for hard rock basaltic basin.
Raja, S, Thomas, PS, Stuart, BH, Guerbois, JP & O'Brien, C 2009, 'The estimation of pig bone age for forensic application using thermogravimetric analysis', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 98, no. 1, pp. 173-176.
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An accurate means of determining bone age is a goal for forensic scientists. In this study, thermogravimetric analysis (TGA) has been used to examine pig bone specimens of different post-mortem age. Analysis of bone in both air and nitrogen atmospheres reveals a decrease in total mass loss as the bones age. Two mass loss steps due to the decomposition of the organic bone components were observed and show decreasing trends with age for decomposition in an air atmosphere. In a nitrogen atmosphere the decomposition was observed to be more complex and age dependence of the mass loss for each step was not identified. The TGA data, however, demonstrates the potential of the technique as a means of estimating post-mortem age of forensic bone specimens.
Regmi, G, Indraratna, B & Nghiem, LD 2009, 'Effective remediation of groundwater in acid sulphate soil terrain', Australian Geomechanics Journal, vol. 44, no. 4, pp. 33-40.
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Acidic groundwater, generated from acid sulphate soil (ASS), is a major geo-environmental problem in Australia. Manipulation of groundwater through the use of weirs and gates in the nearby creeks and drains of ASS, which is being practised right now for preventing pyrite oxidation, is not effective in low land floodplains due to the risk of flooding. The application of a permeable reactive barrier (PRB) can be an alternative for remediation of acidic groundwater in such floodplains. Laboratory column experiments were carried out prior to installation of the PRB for examining the efficiency of the material. Results of these experiments have shown that recycled concrete could effectively neutralise the acidic water for longer periods with complete removal of aluminium (Al) and iron (Fe). Despite the reduction of the efficiency of the recycled concrete due to armouring by accumulated precipitates of Al and Fe, excellent performance was observed for an extended period under controlled laboratory condition. Following these results, a pilot PRB was installed in the Broughton Creek flood plains in southeast NSW to observe its performance under varying natural conditions of the field. The PRB has been maintaining near neutral pH with complete removal of Al and Fe from the groundwater of ASS matching with the results of column test. The promising performance of the pilot PRB for the last three years shows that PRB can be used as one of the cost effective and environmental friendly alternative to other recently utilised techniques in ASS.
Ren, T, Mu, Y, Ni, B & Yu, H 2009, 'Hydrodynamics of upflow anaerobic sludge blanket reactors', AIChE Journal, vol. 55, no. 2, pp. 516-528.
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AbstractThe hydrodynamic characteristics of upflow anaerobic sludge blanket (UASB) reactors were investigated in this study. A UASB reactor was visualized as being set‐up of a number of continuously stirred tank reactors (CSTRs) in series. An increasing‐sized CSTRs (ISC) model was developed to describe the hydrodynamics of such a bioreactor. The gradually increasing tank size in the ISC model implies that the dispersion coefficient decreased along the axial of the UASB reactor and that its hydrodynamic behavior was basically dispersion‐controlled. Experimental results from both laboratory‐scale H2‐producing and full‐scale CH4‐producing UASB reactors were used to validate this model. Simulation results demonstrate that the ISC model was better than the other models in describing the hydrodynamics of the UASB reactors. Moreover, a three‐dimensional computational fluid dynamics (CFD) simulation was performed with an Eulerian‐Eulerian three‐phase‐fluid approach to visualize the phase holdup and to explore the flow patterns in UASB reactors. The results from the CFD simulation were comparable with those of the ISC model predictions in terms of the flow patterns and dead zone fractions. The simulation results about the flow field further confirm the discontinuity in the mixing behaviors throughout a UASB reactor. © 2008 American Institute of Chemical Engineers AIChE J, 2009
Ren, WX, Hao, H & Zhu, X 2009, 'International Journal of Structural Stability and Dynamics: Foreword', International Journal of Structural Stability and Dynamics, vol. 9, no. 4.
Ren, W-X, Hao, H & Zhu, X 2009, 'SPECIAL ISSUE ON STRUCTURAL CONDITION ASSESSMENT, MONITORING AND IMPROVEMENT; EDITE ZHU FOREWORD', INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS, vol. 9, no. 4, pp. V-V.
Rujikiatkamjorn, C & Indraratna, B 2009, 'Design procedure for vertical drains considering a linear variation of lateral permeability within the smear zone', Canadian Geotechnical Journal, vol. 46, no. 3, pp. 270-280.
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A system of vertical drains with surcharge preloading is an effective method for promoting radial drainage and accelerated soil consolidation. This study presents a procedure for the design of vertical drains that significantly extends the previous technique proposed by the authors to include: (i) a linear reduction of lateral permeability in the smear zone, (ii) the effect of overlapping smear zones in a closely spaced drain network, and (iii) the gain in undrained shear strength due to consolidation. Design examples are provided for both single stage and multi-stage embankment construction demonstrating the convenient use of the proposed solutions in practical situations.
Safari, HO, Pirasteh, S & Pradhan, B 2009, 'Upliftment Estimation of the Zagros Transverse Fault in Iran Using Geoinformatics Technology', Remote Sensing, vol. 1, no. 4, pp. 1240-1256.
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Salvestrin, H & Hagare, P 2009, 'Removal of nitrates from groundwater in remote indigenous settings in and Central Australia', DESALINATION AND WATER TREATMENT, vol. 11, no. 1-3, pp. 151-156.
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Naturally occurring elevated levels of nitrates are detected in many of the groundwater bores in the arid zone of Central Australia. Such levels are associated with anemia in young babies, pregnant women and other vulnerable groups. Further, there is evidence that links long-term exposure to elevated levels of nitrates with gastric cancer. In many parts of arid Central Australia alternative sources of water are not available. The capacity to operate and maintain water treatment and supply systems in remote Indigenous communities varies due to access and levels of service provision, mobility of the residents and balance of skills within the communities. A need has thus been identifi ed for a low maintenance nitrate removal system. Conventional treatment processes do not remove nitrates. Alternatives, such as reverse osmosis, ion exchange or biological denitrifi cation are either complex, energy and water intensive, expensive, produce waste products requiring disposal or require continual maintenance and monitoring. Such preconditions are not able to be met in remote Indigenous communities. This paper reviews the problems of nitrates in the arid zone of Central Australia and explores existing technologies for their removal, relative to remote Indigenous settings. It identifi es a need for further investigations to tailor technology to the unique social, economic and cultural characteristics of these settings.
Sheng, D, Gens, A, Fredlund, DG & Sloan, SW 2009, 'Reply to Comments on “Unsaturated soils: From constitutive modelling to numerical algorithms” by Daichao Sheng, Antonio Gens, Delwyn G. Fredlund and Scott W. Sloan [Computers and Geotechnics 35(6) (2008) 810–824] by Jingshuang Li, Yichuan Xing and Yujing Hou', Computers and Geotechnics, vol. 36, no. 6, pp. 1100-1100.
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Sheng, D, Nazem, M & Carter, JP 2009, 'Some computational aspects for solving deep penetration problems in geomechanics', Computational Mechanics, vol. 44, no. 4, pp. 549-561.
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Shon, H, Okour, Y, Saliby, IE, Park, J, Cho, DL, Kim, JB, Park, HJ & Kim, JH 2009, 'Preparation and characterisation of titanium dioxide produced from Ti-salt flocculated sludge in water treatment', Journal of the Korean Industrial and Engineering Chemistry, vol. 20, no. 3, pp. 241-250.
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During the past few years, titanium salts were investigated as alternative coagulants for the removal of organic matter of different molecular sizes in contaminated water. The flocculation efficiency of Ti-salt was comparable to those of FeCl3 and Al2(SO4)3 salts, commonly used coagulants. Incinerated sludge-TiO2 showed higher surface area and photocatalytic activity than commercially available TiO2. Metal-doped forms were produced by adding coagulant aids such as iron (Fe-), aluminium (Al-) and (Ca-) calcium salts during Ti-salt flocculation to increase pH. Ca- and Al- doped TiO2 showed very high photocatalytic activity compared to Fe-doped TiO2. When tested in a pilot scale plant for treatment of dye wastewater to check practical feasibility of the novel process, the removal ratio of the chemical oxygen demand was comparable to those of commonly used coagulants but the settling of sludge was faster. The TiO2 generated after sludge incineration showed a high photocatalytic activity for degradation of volatile organic compounds and increased the rate of hydrogen production by water photosplitting. TiCl4 coagulant and TiO2 produced from different water sources with different concentrations had low acute toxicity compared to heavy metals and commercial TiO2 when examined based on D. Magna mortality. This paper presents the production, characterisation and the photoactivity of TiO2 produced from Ti-salt flocculated sludge. Different case studies are discussed to highlighted recent advances in this field.
Shon, HK, Kim, SH, Vigneswaran, S, Ben Aim, R, Lee, S & Cho, J 2009, 'Physicochemical pretreatment of seawater: fouling reduction and membrane characterization', DESALINATION, vol. 238, no. 1-3, pp. 10-21.
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The pretreatment of raw seawater is necessary to minimize the organic fouling of seawater reverse osmosis (SWRO) membranes. To predict the membrane fouling of the pretreated seawater, the modified fouling index (MFI) with ultrafiltration (UF) was investigated in terms of molecular weight distribution (MWD) and membrane characterization. The study was conducted with seawater drawn from Collioure, France. The concentration of total dissolved solids was 32,760 mg/L. The molecular weight (MW) of the initial seawater organic matter (SWOM) ranged from about 14160 Da to 280 Da. FeCl3 flocculation removed the majority of SWOM, while PAC adsorption could not remove the lowest MW fraction of organic matter (1110, 750 and 280 Da). The UF membranes with 30 kDa and 100 kDa MW cut-off removed the majority of of organic matter corresponding to the peaks 14,160 Da and 6560 Da in MWD. The MFI values obtained when using UF membranes of 30 kDa and 100 kDa with MF pretreatment were 19,700 s/L2 and 31,000 s/L2, respectively. The MFI values after pretreatments of FeCl3 flocculation and PAC adsorption significantly decreased to 6900 s/L2 and 6700 for 30 kDa UF and to 2300 s/L2 and 2500 s/L2 for 100 kDa UF, respectively. Some relation does exist for both membranes between the MFIUF values and Spb values obtained during the first peiod of filtration (pore blocking). The pore blocking zone significantly decreased after flocculation and adsorption pretreatment. This suggests that the pore blocking can be used as an indicator to predict membrane propensity. The detailed membrane characterization on the clean and fouled membrane surface after MFIUF experiments was made in terms of contact angle, zeta potential, functional group and microscopy.
Shon, HK, Puntsho, S, Chon, K, Aryal, R, Vigneswaran, S, Kim, IS & Cho, J 2009, 'A study on the influence of ionic strength on the elution behaviour of membrane organic foulant using advanced separation tools', DESALINATION AND WATER TREATMENT, vol. 11, no. 1-3, pp. 38-45.
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Although membrane technology has become a reliable and viable alternative for water and wastewater treatment, membrane fouling is a serious challenge. In this case study, we report application of different techniques to extract foulant from the hollow fibre membrane and char-acterize the foulant into various components of organic, inorganic and different fractions. The organic foulant was subjected to high-pressure size exclusion chromatography (HPSEC) and flow field-flow fractionation (FlFFF) analysis to study the influence of ionic strength on its elution behaviour using NaCl and CaCl2 as carrier solutions. It was observed that an increase in ionic strength delayed the elution time of both the organic foulant and the Na-salt of Polysterene sulphone (PSS) with HPSEC. However, no such effect was observed with FlFFF analysis. Such study is significant because the characteristics of the membrane organic foulant are believed to be influenced by the carrier ionic conditions and pH and, therefore their subsequent interaction with the membrane and membrane fouling process. However with FlFFF, whether the influence of carrier ionic strength is limited to certain type of ionic carriers or certain groups of natural organic matter is a scope for further research. © 2009 Desalination Publications.
Shon, HK, Vigneswaran, S, Kandasamy, J, Kim, J-B, Park, HJ, Choi, SW & Kim, J-H 2009, 'Preparation of titanium oxide, iron oxide, and aluminium oxide from sludge generated from Ti-salt, Fe-salt and Al-salt flocculation of wastewater', JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY, vol. 15, no. 5, pp. 719-723.
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In this study, the settled floc (sludge) produced by aluminum sulfate (Al2(SO4)3), ferric chloride (FeCl3) and titanium tetrachloride (TiCl4) flocculation was recycled with a novel flocculation process, which has a significant potential to the lower cost of waste disposal, protect the environment and public health and yield economically useful by-products. Three coagulants removed 70% of organic matter in synthetic wastewater. The settled floc was incinerated in the range from 100 8C to 1000 8C. Alumina (Al2O3), hematite (Fe2O3), titanium oxide (TiO2) which are the most widely used metal oxides were produced from the wastewater sludge generated by the flocculation in wastewater with Al2(SO4)3, FeCl3 and TiCl4, respectively. TiO2 particles produced from the sludge consisted of the large amount of nano size particles. Hematite (Fe2O3) and grattarolaite (Fe3 (PO4)O3 or Fe3PO7) included the majority of micro size (40%) particles. Alumina (Al2O3) also consisted of micro size (40%). Due to TiO2 usefulness of the application, detailed characterisation of TiO2 after calcination at different temperatures were investigated in terms of X-ray diffraction, energy dispersive X-ray, surface area and photoactivity.
Shon, HK, Vigneswaran, S, Kandasamy, J, Zareie, MH, Kim, JB, Cho, DL & Kim, J-H 2009, 'Preparation and Characterization of Titanium Dioxide (TiO2) from Sludge produced by TiCl4 Flocculation with FeCl3, Al-2(SO4)(3) and Ca(OH)(2) Coagulant Aids in Wastewater', SEPARATION SCIENCE AND TECHNOLOGY, vol. 44, no. 7, pp. 1525-1543.
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In this study, TiCl4 coagulant together with coagulant aids such as FeCl3, Al2(SO4)3, and Ca(OH)2 were investigated to improve the photoactivity of titanium dioxide (TiO2) produced from sludge and to increase the resulting low pH value. After TiCl4 flocculation with three coagulant aids, the settled floc (sludge) was incinerated at 600°C to produce TiO2 doped with Fe, Al, and Ca elements. Fe-, Al-, and Ca-doped TiO2 was characterized in terms of structural, chemical, and photo-electronic properties. All the coagulant aids used together with Ti-salt flocculation effectively increased the pH values. The surface area of TiO2-WO (without any coagulant aids), Fe/TiO2, Al/TiO2, and Ca/TiO2 was 122 m2/g, 77 m2/g, 136 m2/g and 116 m2/g, respectively. The TiO2-WO, Fe/TiO2, Al/TiO2, and Ca/TiO2 was found to be of anatase phase. The XRD pattern on the Fe/TiO2 included an additional peak of hematite (α-Fe2O3). The majority of gaseous acetaldehyde with TiO2-WO and Ca/TiO2 for photocatalytic activity was completely removed within 40 minutes under UV irradiation.
Siddiquee, N, Parween, S, Quddus, M & Barua, P 2009, 'Heavy Metal Pollution in Sediments at Ship Breaking Area of Bangladesh', ASIAN JOURNAL OF WATER ENVIRONMENT AND POLLUTION, vol. 6, no. 3, pp. 7-12.
Simon, A, Nghiem, LD, Le-Clech, P, Khan, SJ & Drewes, JE 2009, 'Effects of membrane degradation on the removal of pharmaceutically active compounds (PhACs) by NF/RO filtration processes', Journal of Membrane Science, vol. 340, no. 1-2, pp. 16-25.
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Singh, G & Kandasamy, J 2009, 'Evaluating performance and effectiveness of water sensitive urban design', Desalination and Water Treatment, vol. 11, no. 1-3, pp. 144-150.
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Water Sensitive Urban Design (WSUD) is something of a catch-all term for environmentally sustainable water resource management in urban areas. Water sensitive urban design offers an alternative to the traditional conveyance approach to stormwater management. It seeks to minimise the extent of impervious surfaces and mitigate changes to the natural water balance, through on-site reuse of water as well as through temporary storage. By integrating major and minor fl ow paths in the landscape and adopting a range of water sensitive design techniques, the size of the structural stormwater system required can be signifi cantly reduced. WSUD techniques include detention and retention basins to lower peak fl ows, grassed swales and vegetation to facilitate water infi ltration and pollutant fi ltration. WSUD has been adopted widely in Australia and is being implemented in varied local government areas. The major challenge to the success of WSUD is however its measure of effectiveness over the life cycle given that it demands high maintenance. The aim of this paper is to provide a snapshot of effectiveness of WSUD implemented in Kogarah Municipal Council using two case studies and presents results on improvement in water quality through both site specifi c and water quality monitoring of the bays.
Smallwood, A, Thomas, PS, Ray, AS & Simon, P 2009, 'Application of a Fickian model of diffusion to the dehydration of graded specimens of a precious Australian sedimentary opal derived from Coober Pedy', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 97, no. 2, pp. 685-688.
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A model developed for the estimation of the diffusion coefficient based on Fickian diffusion is applied to the dehydration of a Coober Pedy white play of colour (precious) opal using thermogravimetric analysis (TG). The model was originally applied to bulk and powdered opal (opal with no bulk). In this paper the opal was graded prior to TG analysis. The diffusion coefficient was calculated and is reported up to the critical point of water.
Stewart, MG 2009, 'Mechanical behaviour of pitting corrosion of flexural and shear reinforcement and its effect on structural reliability of corroding RC beams', Structural Safety, vol. 31, no. 1, pp. 19-30.
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A spatial time-dependent reliability model is developed for a RC beam subject to corrosion-induced pitting corrosion, for shear and flexural limit states. The analysis considers the spatial and time-dependent variability of pitting corrosion, structural resistance and load effects. The amount of corrosion loss can significantly affect the mechanical behaviour of reinforcement, namely low corrosion loss can result in ductile yielding, whereas a higher corrosion loss can result in brittle fracture. The progression from ductile to brittle behaviour is spatially and time-dependent. To estimate how such phenomena affects structural reliability the structural resistance of reinforcement is modelled as either (i) perfectly ductile parallel system or (ii) perfectly brittle parallel system. It was found that the probability of failure assuming brittle reinforcement behaviour is up to 450% higher than assuming ductile behaviour. © 2008 Elsevier Ltd. All rights reserved.
Stewart, MG & Suo, Q 2009, 'Extent of spatially variable corrosion damage as an indicator of strength and time-dependent reliability of RC beams', Engineering Structures, vol. 31, no. 1, pp. 198-207.
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A spatial time-dependent reliability model is developed for a RC beam subject to corrosion-induced pitting corrosion. The analysis considers the spatial and time-dependent variability of pitting corrosion and its effect on cover cracking and shear and flexural resistance. The model uses extreme value theory to predict maximum pit depth as a function of bar diameter and reinforcing bar length. The effect of corrosion on the mechanical behaviour of reinforcement and associated loss of ductility is also considered. A 1D spatial model is included where concrete properties, concrete cover and the surface chloride concentration are treated as random fields. The model is then used to predict the likelihood and extent of corrosion-induced cracking (corrosion damage). The spatial time-dependent reliability model allows the loss of structural capacity and reliability to be calculated conditional to the observed extent of corrosion damage. This allows the interaction between corrosion damage and loss of structural safety to be inferred for a deteriorating RC beam. It was found that the crack width at time of structural collapse is often well in excess of 1 mm. It was also found that the extent and location of severe cover cracking is an important indicator of structural reliability. © 2008 Elsevier Ltd. All rights reserved.
Suo, Q & Stewart, MG 2009, 'Corrosion cracking prediction updating of deteriorating RC structures using inspection information', Reliability Engineering & System Safety, vol. 94, no. 8, pp. 1340-1348.
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It is well known that the corrosion-induced cracking of reinforced concrete (RC) structures varies in time and space due to the inherent spatial variability of concrete cover, concrete strength, surface chloride concentration and other material, environmental and dimensional properties. A model for predicting the likelihood and extent of RC corrosion-induced cracking considering spatial variability is reviewed. The uncertainties of predictions can be reduced by the effective use of information obtained from visual inspections regarding structural performance, such as cracking proportion and crack width. The paper uses a spatial time-dependent reliability analysis combined with visual inspection data to predict the likelihood and extent of RC corrosion-induced cracking. In this study, RC slabs and beams are used to illustrate the influence of inspection information updating on the future likelihood and extent of corrosion-induced cracking. Concrete strength, concrete cover and the surface chloride concentrations are modelled as spatial variables. Monte-Carlo simulation is employed to calculate the updated cracking proportions. The analysis considers various inspection scenarios which include different inspection intervals, inspection times, cracking proportion and crack width. It was found that the occurrence or observance of cracking changes the future cracking prediction significantly. © 2009 Elsevier Ltd. All rights reserved.
Tijing, LD, Kim, HY, Lee, DH, Kim, CS & Cho, YI 2009, 'Use of an Oscillating Electric Field to Mitigate Mineral Fouling in a Heat Exchanger', Experimental Heat Transfer, vol. 22, no. 4, pp. 257-270.
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Upitis, A, Peterson, J, Lukey, C & Nghiem, LD 2009, 'Metallic ion extraction using polymer inclusion membranes (PIMs): Optimising physical strength and extraction rate', Desalination and Water Treatment, vol. 6, no. 1-3, pp. 41-47.
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Val, DV & Stewart, MG 2009, 'Reliability Assessment of Ageing Reinforced Concrete Structures—Current Situation and Future Challenges', Structural Engineering International, vol. 19, no. 2, pp. 211-219.
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This paper provides a brief description of the framework for reliability-based analysis/assessment of ageing reinforced concrete structures. The main emphasis is made on modelling deterioration due to corrosion of reinforcing steel. A critical overview of existing models for corrosion initiation, corrosion-induced cracking, and effects of corrosion on deflections and strength of reinforced concrete (RC) structures is presented, including discussion of future research needs. Recent accomplishments of the authors in this area are described. Special attention is paid to the role of spatial variability of deterioration on results of reliability assessment, which is illustrated by two examples.
Val, DV, Chernin, L & Stewart, MG 2009, 'Experimental and Numerical Investigation of Corrosion-Induced Cover Cracking in Reinforced Concrete Structures', Journal of Structural Engineering, vol. 135, no. 4, pp. 376-385.
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In the paper corrosion-induced crack initiation and propagation are investigated experimentally and numerically, with particular emphasis on quantifying the proportion of corrosion products that are dissipated within the concrete pores and cracks, thus reducing the pressure exerted by corrosion products on the surrounding concrete. Initially, experimental data on crack initiation and propagation obtained from accelerated corrosion tests of reinforced concrete slabs are presented. A comparison of finite-element model results and experimental data is used to estimate the amount of corrosion products penetrating into concrete pores and cracks, which is an essential parameter for prediction of corrosion initiation and propagation. It was found that the amount of corrosion products penetrating into the concrete pores before crack initiation is larger than that obtained by other researchers. The paper also showed that corrosion products do not fully fill corrosion-induced cracks in concrete immediately after their initiation as the cracks are being filled gradually over time and the thicker the concrete cover the longer it will take to fully fill a crack. © 2009 ASCE.
Vessalas, K, Ray, AS, Thomas, P, Sri Ravindrarajah, R, Joyce, PA & Haggman, J 2009, 'Pitchstone Fines - A New Naturally Occuring Pozzolan from North Queensland', Concrete Forum, vol. 2, no. 1, pp. 11-15.
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Global warming presents an ever-challenging battle to humankind, as emissions arising from industrially produced gteenhouse gases are predicted to alter the long-term climatic patterns of earth. Harmful environmental emissions arising during the manufactute of Portland cements (C) can be effectively reduced by incorporating siliceous-aluminous based supplementary cementitious materials (SCMs), as partial cement replacements. In Australia, mined pitchstone fines (PF), derived as waste material from expandable perlire production, area viable SCM for reducing cement consumption using an eco-friendly approach. This paper reports on the results of an experimental investigation into the pozzolanic activity of PP. Up to 40% cement was replaced with PF in mortar mixes. In addition, PP was used to partially replace sand. Strength activity index (SM) values for PP were evaluated using accelerated 28-day compressive strengths for all PP substitution levels, with flows and wet densities of mortar mixes reported.
Vessalas, K, Thomas, PS, Ray, AS, Guerbois, J-P, Joyce, P & Haggman, J 2009, 'Pozzolanic reactivity of the supplementary cementitious material pitchstone fines by thermogravimetric analysis', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 97, no. 1, pp. 71-76.
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Thermogravimetric (TG) analysis was applied to the characterisation of the pozzolanic reaction in mortars containing the supplementary cementitious materials (SCMs) pitchstone fines (PF) and fly ash (FA) as partial replacements for Portland cement (PC). TG analysis was used to determine the proportion of calcium hydroxide (CH) present from the hydration of the PC based on the dehydroxylation of the CH present in the blended PC-SCM mortars. The consumption of CH indicated that both SCMs underwent the pozzolanic reaction and that PF was found to compare favourably in its pozzolanic reactivity of FA, the industry and globally accepted standard artificial pozzolan.
VEXLER, A & WU, C 2009, 'An Optimal Retrospective Change Point Detection Policy', Scandinavian Journal of Statistics, vol. 36, no. 3, pp. 542-558.
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Abstract. Since the middle of the twentieth century, the problem of making inferences about the point in a surveyed series of observations at which the underlying distribution changes has been extensively addressed in the economics, biostatistics and statistics literature. Cumulative sum‐type statistics have commonly been thought to play a central role in non‐sequential change point detections. Alternatively, we present and examine an approach based on the Shiryayev–Roberts scheme. We show that retrospective change point detection policies based on Shiryayev–Roberts statistics are non‐asymptotically optimal in the context of most powerful testing.
Vexler, A, Wu, C, Liu, A, Whitcomb, BW & Schisterman, EF 2009, 'An extension of a change-point problem', Statistics, vol. 43, no. 3, pp. 213-225.
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We consider a specific classification problem in the context of change-point detection. We present generalized classical maximum likelihood tests for homogeneity of the observed sample in a simple form which avoids the complex direct estimation of unknown parameters. This paper proposes a martingale approach to transformation of test statistics. For sequential and retrospective testing problems, we propose the adapted Shiryayev-Roberts statistics in order to obtain simple tests with asymptotic power one. An important application of the developed methods is in the analysis of exposure's measurements subject to limits of detection in occupational medicine. © 2009 Taylor & Francis.
Vu, NA, Castel, A & François, R 2009, 'Effect of stress corrosion cracking on stress–strain response of steel wires used in prestressed concrete beams', Corrosion Science, vol. 51, no. 6, pp. 1453-1459.
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Walker, R & Indraratna, B 2009, 'Consolidation analysis of a stratified soil with vertical and horizontal drainage using the spectral method', Géotechnique, vol. 59, no. 5, pp. 439-449.
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A novel use of the spectral method to determine excess pore water pressure during vertical consolidation of multi-layered soil with time constant material properties is presented, considering a unit cell with combined vertical and radial drainage. Equal strain conditions are assumed in the analysis. The novel adoption of material properties that vary in a linear fashion with depth allows arbitrary distributions of properties to be modelled. By incorporating surcharge and vacuum loading that vary with both depth and time, a wide range of consolidation problems can be analysed. The spectral method is a meshless approach producing a series solution to the consolidation problem based on matrix operations. Accuracy can be improved by increasing the number of terms used in the series solution. The model is verified by the analysis of selected case studies characterised by: analytical free strain consolidation with thin sand layers (surcharge only); laboratory test and embankment trial with surcharge and vacuum loading; and ground subsidence caused by groundwater pumping.
Walker, R, Indraratna, B & Sivakugan, N 2009, 'Vertical and Radial Consolidation Analysis of Multilayered Soil Using the Spectral Method', Journal of Geotechnical and Geoenvironmental Engineering, vol. 135, no. 5, pp. 657-663.
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Wang, Y, Zhu, X, Hao, H & Ou, J 2009, 'Guided wave propagation and spectral element method for debonding damage assessment in RC structures', Journal of Sound and Vibration, vol. 324, no. 3-5, pp. 751-772.
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Wu, C, Chen, W & Oehlers, DJ 2009, '10.4028/0-87849-349-2.795', Key Engineering Materials, vol. 400-402, pp. 795-800.
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Currently, there are adequate guidelines available for FRP retrofitting RC structures against static and seismic loads. However, there is still limited information on retrofitting RC structures against short-duration dynamic loading effects such as blast loading. Due to the increasing threat of terrorism in recent years, retrofitting of RC structures against blast loading is of paramount importance in structural engineering. In this paper, a dynamic model that is based on single-degree-of-freedom (SDOF) approach is developed for the analysis of the response of retrofitted fixed end supported RC slabs subjected to blast loads. A previously validated layered capacity analysis method is used to determine the yielded and ultimate blast resistant capacity of a cross-section of a RC slab which allows varying strain rates with time along the depth of the member. The corresponding deflections are determined by plastic hinge analysis. To simplify the calculation process, a tri-linear resistance-deflection function which consists of elastic, elasto-plastic and plastic region for fixed end supported RC slabs is converted to an equivalent bilinear function. This developed model can adequately predict the retrofitted members' response to blast loading. It is then is used to conduct a parametric study to optimise the retrofitting of RC slabs subjected to blast loading by varying the quantity, material type and technique of retrofitting.
Wu, C, Nurwidayati, R & Oehlers, DJ 2009, 'Fragmentation from spallation of RC slabs due to airblast loads', International Journal of Impact Engineering, vol. 36, no. 12, pp. 1371-1376.
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Wu, C, Oehlers, DJ & Day, I 2009, 'Layered Blast Capacity Analysis of FRP Retrofitted RC Member', Advances in Structural Engineering, vol. 12, no. 3, pp. 435-449.
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Fibre reinforced polymer (FRP) retrofitting of RC structures against blast loading is an emerging research area of major significance. Currently, several guidelines are available for the FRP retrofitting of RC structures against monotonic and seismic loads. However, no advice is provided from these guidelines for the retrofit RC structures against blast loading. This paper formulates a layered model that allows for both FRP strengthening and the consideration of strain rate effects on the blast resistant capacity of flexural structural members. The layered model is incorporated into a single degree of freedom model for dynamic analyses and it is validated with blast tests. The validated model is then used in a parametric study which investigates the changes in strength, ductility and energy absorption capacities of flexural FRP strengthened members under blast loads. It is found that the capacity of a flexural member to resist a blast load can be increased greatly with the use of compressive face plating with the ductility of the flexural member being the key factor.
Wu, C, Oehlers, DJ, Rebentrost, M & Leach, J 2009, '10.4028/0-87849-349-2.107', Key Engineering Materials, vol. 400-402, pp. 107-112.
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Displacement-controlled design method is now being used by current guidelines such as TM5 and ASCE to design RC members against airblast load. If the maximum deflection of the designed member under airblast loads is less than the allowable deflection, the designed member is considered to be safe. Although the displacement-controlled design method is easy to use, it may not result in a design having maximum energy-absorption capacity against airblast loads, especially for a design of a reinforced ultra-high performance fibre concrete (RUHPFC) member which is of both high strength and high ductility, that is, high energy-absorption capacity. In this paper, a layered analysis model allowing for varying strain rates with time as well as along the depth of the member was used to calculate energy-ab sorption of a simple supported RUHPFC slab under airblast loads. An optimal reinforcement ratio of the slab was achieved by maximizing the energy absorption of the slab under different reinforcement ratios. The energy-controlled design method was validated by field blast tests. Using the validated design method, a designed slab with the optimal reinforcement ratio was also tested and the effectiveness of the design was demonstrated.
Wu, C, Oehlers, DJ, Rebentrost, M, Leach, J & Whittaker, AS 2009, 'Blast testing of ultra-high performance fibre and FRP-retrofitted concrete slabs', Engineering Structures, vol. 31, no. 9, pp. 2060-2069.
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Wu, D, Liu, X, Wang, L, Wang, L, Xu, M, Sun, T, Yang, Z & Zhou, J 2009, 'QSARs on the Depuration Rate Constants of Polycyclic Aromatic Hydrocarbons in Elliptio complanata', QSAR & Combinatorial Science, vol. 28, no. 5, pp. 537-541.
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AbstractUsing quantum chemical descriptors and partial least squares (PLS) regression, a quantitative structure–activity relationships (QSARs) model was developed to predict the depuration rate constants (kd) of polycyclic aromatic hydrocarbons (PAHs) for mussels, Elliptio complanata (log kd=−2.1406+0.6013DE−2.0767×10−3 Mw−0.201EHOMO). With a high cumulative cross‐validated regression coefficient value (Q$\rm{ {_{cum}^{2}}}$) of 0.927 and low standard deviation (SD) of 0.065, the model obtained by the training set shows a good predictive ability, and it is validated to be robust by predicting the test set. Among 20 quantum chemical descriptors, the dielectric energy (DE), the molecular weight (Mw), and the highest occupied molecular orbital energy (EHOMO) are the key descriptors governing the logkd values in the model. Increase in the DE or decrease in the Mw values leads to the increase in logkd, indicating the van der Waals interactions and steric hindrance effect on the depuration process. Decrease in the EHOMO values results in increasing the logkd values, implying important roles the molecular orbital energies may play in the biological depuration of...
Yanti, PAA & Mahlia, TMI 2009, 'Considerations for the selection of an applicable energy efficiency test procedure for electric motors in Malaysia: Lessons for other developing countries', Energy Policy, vol. 37, no. 9, pp. 3467-3474.
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Ying, Z & Zhu, X 2009, 'Response analysis of piezoelectric shells in plane strain under random excitations', Acta Mechanica Solida Sinica, vol. 22, no. 2, pp. 152-160.
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Youssef, AM, Pradhan, B, Gaber, AFD & Buchroithner, MF 2009, 'Geomorphological hazard analysis along the Egyptian Red Sea coast between Safaga and Quseir', Natural Hazards and Earth System Sciences, vol. 9, no. 3, pp. 751-766.
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Abstract. Geomophological hazard assessment is an important component of natural hazard risk assessment. This paper presents GIS-based geomorphological hazard mapping in the Red Sea area between Safaga and Quseir, Egypt. This includes the integration of published geological, geomorphological, and other data into GIS, and generation of new map products, combining governmental concerns and legal restrictions. Detailed geomorphological hazard maps for flooding zones and earth movement potential, especially along the roads and railways, have been prepared. Further the paper illustrates the application of vulnerability maps dealing with the effect of hazard on urban areas, tourist villages, industrial facilities, quarries, and road networks. These maps can help to initiate appropriate measures to mitigate the probable hazards in the area.
Zhang, R, Castel, A & François, R 2009, 'Serviceability Limit State criteria based on steel–concrete bond loss for corroded reinforced concrete in chloride environment', Materials and Structures, vol. 42, no. 10, pp. 1407-1421.
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Zhang, R, Castel, A & François, R 2009, 'The corrosion pattern of reinforcement and its influence on serviceability of reinforced concrete members in chloride environment', Cement and Concrete Research, vol. 39, no. 11, pp. 1077-1086.
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Zhang, R, Khorshed, C, Vigneswaran, S & Kandasamy, J 2009, 'Submerged microfiltration coupled with physcio-chemical processes as pretreatment to sea water desalination', Desalination and Water Treatment, vol. 11, no. 1-3, pp. 52-57.
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In this study, the critical fl ux of the submerged membrane system was experimentally evaluated when it was used for seawater with and without pre-treatment. In this study, different processes such as fl occulation with ferric chloride (FeCl3) and different doses of PAC adsorption were used as a pre-treatment. The pretreatment of fl occulant of 2 mg/L of FeCl3 and adsorption with the dose of 1 g/L PAC showed an improvement in the critical fl ux from 5 L/m2.h to 6.7 L/m2.h and 13.3 L/m2.h respectively. The performance of these pretreatments was also determined in terms of modifi ed fouling index using ultrafi lter membrane (UF-MFI). UF-MFI and SDI indicated that PAC adsorption was a better pretreatment than fl occulation for the seawater used in this study. Molecular weight distribution (MWD) of seawater organic matter was also examined after different pretreatments. MWD of the raw seawater was mainly in the range from 1510 to 130 Da. It is observed that FeCl3 fl occulation and PAC adsorption as pretreatments partially removed the organic matter of 1510 Da and 130Da respectively
Zhao, B-H, Yue, Z-B, Ni, B-J, Mu, Y, Yu, H-Q & Harada, H 2009, 'Modeling anaerobic digestion of aquatic plants by rumen cultures: Cattail as an example', Water Research, vol. 43, no. 7, pp. 2047-2055.
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Zhou, A & Sheng, D 2009, 'Yield stress, volume change, and shear strength behaviour of unsaturated soils: validation of the SFG model', Canadian Geotechnical Journal, vol. 46, no. 9, pp. 1034-1045.
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The model recently presented by Sheng, Fredlund, and Gens, known as the SFG model, provides a consistent explanation of yield stress, shear strength, and volume change behaviour of unsaturated soils as functions of suction. All these functions are based on one single equation that defines the volume change with suction and stress changes. This paper provides a systematic validation of the equation and the derived shear strength criterion against experimental data. The experimental data used include those for samples prepared from slurry soils and compacted soils. It is shown that (i) the method currently used to determine yield stresses of unsaturated soils is incorrect, (ii) volume change behaviour of unsaturated soils can be well predicted by the SFG model, and (iii) shear strength behaviour of unsaturated soils can be represented very well by the criterion in the SFG model.
Zhou, JL, Zhang, ZL, Banks, E, Grover, D & Jiang, JQ 2009, 'Pharmaceutical residues in wastewater treatment works effluents and their impact on receiving river water', Journal of Hazardous Materials, vol. 166, no. 2-3, pp. 655-661.
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Various pharmaceutical residues are being discharged from wastewater treatment works (WTW) effluents, the impact of which on river water quality is of high relevance to environmental risk assessment. The concentrations of eleven pharmaceutical compounds were determined in three WTWs in England, and the river Ouse receiving effluents from Scaynes Hill WTW. Results show that five compounds propranolol, sulfamethoxazole, carbamazepine, indomethacine and diclofenac were detected in all wastewater and river water samples, with carbamazepine showing the highest concentrations (up to 2336 ng L-1) in WTW influent. Different compounds were removed to different extent in the WTWs, varying from 43 to 92%, with the highest performance obtained by the WTW with tertiary treatment (sand filtration). The pharmaceutical residues from Scaynes Hill WTW were eventually discharged into the river Ouse, causing an elevation in their concentrations downstream of the outfall. This was confirmed by the good agreement between measured concentrations and those predicted by a simple dilution model. © 2008 Elsevier B.V. All rights reserved.
ZHU, X & HAO, H 2009, 'DAMAGE DETECTION OF RC SLABS USING NONLINEAR VIBRATION FEATURES', International Journal of Structural Stability and Dynamics, vol. 09, no. 04, pp. 687-709.
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Studied herein are the signatures of nonlinear vibration characteristics of damaged reinforced concrete structures using the wavelet transform (WT). A two-span RC slab built in 2003 was tested to failure in the laboratory. Vibration measurements were carried out at various stages of structural damage. The vibration frequencies, mode shapes, and damping ratios at each loading stage were extracted and analyzed. It is found that the vibration frequencies are not sensitive to small damages, but are good indicators when damage is severe. The dynamic responses are also analyzed in the time–frequency domain by WT and the skeleton curve is constructed to describe the nonlinear characteristics in the reinforced concrete structures. The results show that the skeleton curves are good indicators of damage in the reinforced concrete structures because they are more sensitive to small damages than vibration frequencies.
Zhu, XQ, Law, SS & Hao, H 2009, 'Damage assessment of reinforced concrete beams including the load environment', Structural Engineering and Mechanics, vol. 33, no. 6, pp. 765-779.
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Aoki, Y, Sri Ravindrarajah, R & Khabbaz, H 1970, 'Effect Of Fly Ash Performance Of Pervious Concrete', Ninth ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete and Tenth ACI International Conference on Recent Advances in Concrete Technology and Sustainability Issues - SUPPLEMENTARY PAPERS, ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete and Tenth ACI International Conference onRecent Advances in Concrete Technology and Sustainability Issues, ACI International Conference, Seville, Spain, pp. 511-520.
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Production of good quality pervious concrete is necessary to meet specification requirements for the construction of durable concrete pervious pavements. This paper reports and discusses the results of an experimental investigation into the physical and engineering properties ofpervious concrete having varying amounts of fly ash as the cement replacement material. The following properties were studied: porosity density, compressive strength weight loss on drying, free drying shrinkage and water permeability. The results thowed that porosity has significant effect on compressive strength and permeability of pervioos concrete. Replacement of cement with fly ash up to 50%, by mass ofbinder, had no significant effect on the water permeability and shrinkage ofshe pervious concrete, although marginal effect on strength was noticed.
Babister, KM, Retallick, ME & Ball, JE 1970, 'Two dimensional simulation in urban areas', Proceedings of H2009 the 32nd Hydrology and Water Resources Symposium, Hydrology and Water Resources Symposium, Engineers Australia, Newcastle, Australia, pp. 430-438.
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A number of areas associated with current practices for floodplain modelling have been highlighted during the revision of ARR as requiring further investigation. One of these areas and hence the reason for one of the revision projects is the need for guidance on 2D modelling in urban areas. This need for guidance has increased as 2D models have become the tool of choice for prediction of flood behaviour within urban floodplains throughout Australia. These 2D models also are being used to simulate rainfall-runoff processes that traditionally have been modelled using conceptual lumped storage rainfall-runoff routing models. The revision project implemented to satisfy this need adopted a non-traditional approach. Instead of inviting a small group of authors to write the project report, a team of authors that represented model suppliers, experienced users, academics and clients from across Australia was assembled. The team used an online wiki tool to develop content collaboratively. Outlined in this paper are the process, experiences learned and details of the final report arising from this project.
Ball, JE, Babister, KM & Phillips, B 1970, 'Estimation of Design Flood Flows Considering Climate Change', 33rd IAHR Congress Water Engineering For A Sustainable Environment, International Association of Hydraulic Engineering & Research, International Association of Hydraulic Engineering and Research, Vancouver, Canada, pp. 734-740.
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Since 1958, when it was first released, Australian Rainfall and Runoff has remained one of the most influential and widely used guidelines for estimation of flood flows in Australia. Since publication of the current edition, initially published in 1987, there have been advances in the theory of flood flows and changes in the application of engineering hydrology to the estimation of flood flows which warrant updating of the current document. One area where these advances have been significant has been in the understanding of the potential for climate change and the influence on current estimates of flood flows. As a result of these advances, the Federal Department of Climate Change in conjunction with EngineersAustralia has developed a funding package for the Australian Rainfall and Runoff Revision Projects. Presented herein are details of the projects undertaken as part of this funding package and how the information from these projects will be utilised in the revision of Australian Rainfall and Runoff.
Bjarnadottir, S, Li, Y & Stewart, MG 1970, 'The potential impact of climate change on hurricane risk assessment', 11th Americas Conference on Wind Engineering.
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This paper presents a framework to assess the potential for increased hurricane risk to residential construction under various wind speed increase scenarios due to climate change. The framework includes a probabilistic hurricane wind field model and a hurricane damage model. A case study of Miami-Dade County, Florida is presented to illustrate the framework. Demographic information, such as median house value and changed house numbers, and distribution of houses on different exposure, are used to estimate the probable damage with or without the increased wind speed. This study finds that climate change may have a substantial impact on the damage and loss estimation in coastal areas.
Chakraborty, S & Yeh, C-H 1970, 'A simulation comparison of normalization procedures for TOPSIS', 2009 International Conference on Computers & Industrial Engineering, Industrial Engineering (CIE39), IEEE, Troyes, FRANCE, pp. 1815-1820.
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Choudhury, D & Nimbalkar, S 1970, 'Seismic stability of tailings dam by using pseudo-dynamic method', Proceedings of the 17th International Conference on Soil Mechanics and Geotechnical Engineering: The Academia and Practice of Geotechnical Engineering, pp. 1542-1545.
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Seismic stability of tailings dams and embankments is an important topic which needs the special assessments by the researchers as it is mainly governed by the safety concerns. Several researchers in the past had attempted to investigate the seismic stability of earthen dams and embankments by using conventional pseudo-static method of analysis. However, the crude estimate of finding the approximate seismic acceleration makes the pseudo-static approach too conservative to adopt in the stability assessment. Although a few researchers in the recent past highlighted the limitations and drawbacks of the pseudo-static approach, there are very limited studies being reported worldwide for the seismic stability assessment of earthen dams and embankments by using alternative methods of analysis. In this paper, a recently developed and modified pseudo-dynamic method of analysis is used to compute the seismic inertia forces acting on the sliding wedge of the tailings dam by considering the effects of time of seismic accelerations, phase differences in the propagating shear and primary waves in the soil during an earthquake, frequency of earthquake excitation etc. with the horizontal and vertical seismic accelerations. The factor of safety decreases with increase in the seismic accelerations and phase difference in body waves. Influence of various parameters such as seismic acceleration coefficients, period of lateral shaking on seismic stability of tailings dam are studied under harmonic seismic loading conditions for both empty and full water cases. Present results are compared with the pseudo-static based solutions to validate the findings of the pseudo-dynamic method of analysis. © 2009 IOS Press.
Christie, D, Nimbalkar, S & Indraratna, B 1970, 'The performance of rail track incorporating the effects of ballast breakage, confining pressure and geosynthetic reinforcement', Bearing Capacity of Roads, Railways and Airfields - Proceedings of the 8th International Conference on the Bearing Capacity of Roads, Railways and Airfields, 8th International Conference on the Bearing Capacity of Roads, Railways and Airfields, CRC Press, Champaign, IL, pp. 5-24.
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Rail tracks are often placed on ballast which offers the desirable resiliency to cyclic loads. However ballasted beds need periodic maintenance due to deformation and degradation associated with breakage and fouling. A proper understanding of load transfer mechanisms and their effect on ballast breakage are prerequisites for minimizing maintenance costs. Recycled ballast is a cheaper and environmentally viable option but its strength characteristics need to be investigated beforehand. This paper demonstrates the analytical, numerical and laboratory investigations carried out to investigate the geotechnical behavior of ballast, including shear strength, ballast breakage, and confining pressure. The potential use of geosynthetics for improving the stability and drainage of railway tracks under high monotonic and cyclic loading is also studied. Field tests were carried out to measure the in-situ stresses of ballast on a section of instrumented track funded and built by RailCorp, Australia. © 2009 Taylor & Francis Group, London.
Ding, GK & Ge, J 1970, 'Green revolution - a challenge to improve environmental performance of existing housing stocks', 2009 Conference on Green Building: Towards Eco-City, Conference on Green Building: Towards Eco-City, Architecture and Building Research Institute, Ministry of the Interior, Taipei, Taiwan, pp. 135-149.
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Climate change is one of the most pressing issues facing Australia today. This is a challenge and responsibility that is shared by all Australian households. Improvements to energy and water efficiency of houses can significantly cut greenhouse gas emissions and reduce utility bills. In July 2004 the New South Wales (NSW) government introduced the Building Sustainability Index (BASIX) to assess potential performance of a dwelling against a set of pre-determined criteria. Housing construction in NSW is the first in Australia to be subjected to mandatory sustainability requirements. BASIX is an online assessment tool which sets scores required to obtain development approval in new residential projects. BASIX is mandated only to improve environmental performance of new residential buildings and does not attempt to improve environmental performance of existing housing stocks which continue to consume natural resources and pollute the environment. Existing houses represent approximately 98% of residential building stocks in NSW and any improvement to these dwellings will have a profound impact on reducing the negative effects of the environment. This paper examines the sustainable upgrading strategies in improving environmental performance of three existing single dwellings in meeting the minimum BASIX requirements. This paper presents an economic analysis of sustainable upgrading using Net Present Value. The results suggest that sustainable upgrading of existing housing stocks is feasible and the scheme will be more attractive if the payback period is reduced with further government financial assistance.
Francois, R, Castel, A & Zhang, R 1970, 'Effect of corrosion on load-bearing capacity and flexural stiffness of reinforced concrete elements', RILEM Workshop on Long-Term Performance of Cementitious Barriers and Reinforced Concrete in Nuclear Power Plants, NUCPERF 2009, RILEM Workshop on Long-Term Performance of Cementitious Barriers and Reinforced Concrete in Nuclear Power Plants, R I L E M PUBLICATIONS, Cadarache, FRANCE, pp. 23-31.
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This article deals with the long term performance of reinforced concrete elements aged in chloride environment. The analysis of the initiation phase of corrosion show that for a same concrete an increase of concrete cover is not sufficient to delay the onset of corrosion. The analysis of the serviceability of reinforced concrete members allows to highlight two different behaviours during the propagation phase: The first phase points out a decrease of the stiffness of reinforced concrete element due to the decrease of bond between rebars and this phase is followed by a stabilisation of stiffness when the bond is totally loss; then the corrosion process could continue without external sign or warnings. The analysis of the load-bearing capacity after 14 and 23 years allows to understand the relationship between the ultimate load and the steel cross-section reduction due to corrosion. Regarding the structural performance reduction, results have shown that the propagation period can be as long as the initiation phase in the service life. Therefore, the propagation period should be considered as a normal step in the service life.
Ge, J & Ding, GK 1970, 'Energy efficient and water reduction programs on households in Australia', 2009 Conference on Green Building: Towards Eco-City, Conference on Green Building: Towards Eco-City, Architecture and Building Research Institute, Ministgry of the Interior, Taiwan, pp. 56-66.
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In 2009, the Australian government has formulated strategies to provide $3.9 billion Energy Efficient Home Package for cutting energy waster and $12.9 billion Water for the Future plan for reducing the use of drinking water, aim of tackling climate change and reducing green house emission. Under the strategies, there are incentive schemes for households of the existing homes, which include a) rebates of up to $500 for installing a new rainwater tank or a permanent grey water treatment system; b) offers of up to $1,600 ceiling insulation or installation of solar hot water system or an assistance of up to $1,000 installing insulation in private rental properties; c) cash rebates of up to $8,000 for the installation of solar photovoltaic systems on homes; and d) providing detailed, quality household sustainability assessments and green renovations packs to Australian households as well as access to low interest Green Loans of up to $10,000 each to make existing homes more energy and water efficient. This paper studies whether the incentive schemes motivate households and how much attraction of the schemes for households. The paper starts to review government policies for home energy efficient and water reduction programs in Australia and compare schemes provided by other countries. Case studies on incomes and expenses for a standard family, costs and benefits, as well as elements impact on households of taking the government incentive schemes are examined. The paper comments on the current incentive programs provided by the government and argue that education on attitude toward saving electricity and water should be one of the important parts of the programs.
Ge, JX & Ding, GKC 1970, 'Cost Effective and Sustainable?: Photovoltaic (PV) Rebate Program in Australia', 2009 International Conference on Management and Service Science, 2009 International Conference on Management and Service Science (MASS), IEEE, Beijing, China, pp. 1-4.
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The Australian Government has recently announced a Renewable Energy Target (RET) scheme to provide up front payments of $8,000 for around 25,250 households of income less than $100,000 per year installing a 150 watt solar panel system starting on 01 July 2009 using $202 million taxpayers' money. The scheme has not included households' with incomes greater than $100,000, nor developers who produce new houses. Whether the policies are effective and sustainable is arguable. This paper examines policies designed to encourage households to install solar panel system in Australia and demonstrates reasons for supporting developers to build green houses using Net Present Value (NPV) analysis in a case study. The findings suggest that the government should support installation of solar systems by both households and the developers. ©2009 IEEE.
Gerber, C & Crews, K 1970, 'Timber stressed-skin panels: Design guidelines for Australian practice', AUSTRALIAN JOURNAL OF STRUCTURAL ENGINEERING, Australian Structural Engineering Conference, TAYLOR & FRANCIS AS, Melbourne, pp. 207-216.
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Gray, SD & Ball, JE 1970, 'Coupled One and Two-Dimensional Modelling in Urban Catchments-Reducing Uncertainty in Flood Estimation', Proceedings of H2009 the 32nd Hydrology and Water Resources Symposium, Hydrology and Water Resources Symposium, Engineers Australia, Newcastle, Australia, pp. 420-429.
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This study tests the 1D/2D coupled modelling approach on its ability to emulate the âroadâ portion of runoff which is conveyed in the kerb/gutter alignment. The event modelled is an approximately 1 in 1 year ARI event in magnitude. Given itâs small ARI it may be supposed that it is mainly comprised of runoff from impervious surfaces (10% roof and 90% road and others). In the event flow from the road moves as sheet flow to the kerb where it is routed to inflow pits. Via the pits it enters the pipe and at the downstream end of the pipe it is gauged. The modelling system is found to be capable of matching the gauged hydrograph for the relatively small event very well. What is also found however is that model parameters that might, in a 1D model, be relatively well informed by field inspection, are instead required to be altered outside recommended ranges in order to optimise the fit between gauged and modelled flow. That is, there is a degree of conceptualisation in the 1D/2D system that was unexpected.
Hao, H, Ding, L & Zhu, X 1970, 'INTERACTION BETWEEN VEHICLE AND BRIDGE WITH DIFFERENT RANDOM SURFACE ROUGHNESS AND ITS IMPLICATION ON DYNAMIC AXLE LOADS', ENVIRONMENTAL VIBRATIONS: PREDICTION, MONITORING, MITIGATION AND EVALUATION, VOLS I AND II, 4th International Symposium on Environment Vibrations - Prediction, Monitoring, Mitigation and Evaluation, SCIENCE PRESS BEIJING, Beijing, PEOPLES R CHINA, pp. 1117-1125.
Haskett, M, Ali, MSM, Oehlers, DJ & Wu, C 1970, 'Influence of Bond on the Hinge Rotation of FRP Plated Beams', Advances in Structural Engineering, SAGE Publications, pp. 833-843.
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Fibre reinforced polymer (FRP) plate reinforcement is a brittle material which has a brittle interfacial bond with concrete. This can lead to the misconception that all FRP retrofitting techniques provide brittle members and, hence, limited rotational capacity which has severe limitations for structural applications. This paper shows that the FRP reinforcement behaviour is but one of three components that govern the rotational capacity of plated reinforced concrete beam hinges. It is shown that FRP retrofitted beams and slabs can achieve ductile behaviour and provide rotational capacity and, furthermore, that the rotational capacity of FRP plated members depends very importantly on the interface bond characteristics.
He, X, Jin, G & Wang, J 1970, 'Space Camera Imaging Gain In-Orbit Adjusting Strategy', 2009 Second International Conference on Intelligent Computation Technology and Automation, 2009 Second International Conference on Intelligent Computation Technology and Automation, IEEE.
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Hicks, B, Gray, SD & Ball, JE 1970, 'A critical review of the Urban Rational Method', Proceedings of H2009 the 32nd Hydrology and Water Resources Symposium, Hydrology and Water Resources Symposium, Engineers Australia, Newcastle, Australia, pp. 1424-1433.
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Since ARR 1987 improved statistical techniques have been presented which are ideal for producing regression relationships relating different catchment characteristics to peak flow. A unique feature of the quantile regression technique is that as different catchment characteristics become more or less important to peak flow their varying significance can be incorporated. For example the importance of losses declines for larger longer events where previous areas become saturated and start to contribute runoff. As a first step towards carrying out the quantile regression work, a database of available gauged data has been compiled. The data base is still being finalised however at the end of the proofing process, whereby gauges are checked for length of record, completeness, quality, ratings, stability of upstream development, it is expected that only a handful of gauges will be found to be suitable. Given the paucity of data it is not possible to establish relationships, by regression, between various catchment characteristics and peak flow for urban catchment. Thus the paper calls for a focus on urban gauging in Australia. This paper suggests that a goal be established, for the establishment of urban gauging sites across Australia (and the maintenance of existing sites) with the suggestion being that such work can be funded as part of climate change research.
Hongsheng, H, Jiong, W, Suxiang, Q, Yancheng, L & Xuezheng, J 1970, 'Investigation on controllability of a Magnetorheological gun recoil damper', 2009 International Conference on Information and Automation, 2009 International Conference on Information and Automation (ICIA), IEEE, pp. 1044-1049.
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Its primary purpose of this study is to provide a comprehensive investigation on the controllability of a Magnetorheological (MR) gun recoil damper. Performances of MR damper under random load, mainly in the transportation applications, seismic protection in civil engineering and windrain- induced load in Cable Bridge, have been well investigated by many researchers. However, little research has been focused on the dynamic performance and its controllability of MR damper under impact load. At present, a systematic architecture has still not been formed, including its structure design, dynamicmodelling and controlling method of a MR damper subjected to impact load. In this paper, the research is developed and aims at the MR gun recoil damper. To evaluate its controllability of a MR gun recoil damper, a test rig which uses a closed bump to produce an impact load is developed. A novel large-scale singleended MR damper without the accumulator is used as the specimen. First, impact tests were done to evaluate the response time of the special designed long-stroke MR gun recoil damper, corresponding to the step signal of the operating current. Then, three revised control strategies, including on-off control method, PID control method, adaptive fuzzy control method, were investigated to confirm its controllability of the MR damper under impact load. Compared with on-off control and PID control policy, it is indicated by test results that this developed MR gun recoil damper has a bette r controllability using the adaptive fuzzy control policy. © 2009 IEEE.
Hongsheng, H, Jiong, W, Suxiang, Q, Yancheng, L, Xuezheng, J & IEEE 1970, 'Investigation on Controllability of a Magnetorheological Gun Recoil Damper', ICIA: 2009 INTERNATIONAL CONFERENCE ON INFORMATION AND AUTOMATION, VOLS 1-3, 2nd International Conference on Smart Materials and Nanotechnology in Engineering, SPIE-INT SOC OPTICAL ENGINEERING, Weihai, PEOPLES R CHINA, pp. 1023-1028.
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Hongsheng, H, Juan, W, Jiong, W, Yancheng, L & Xuezheng, J 1970, 'Investigation on its properties for MR damper under high impact load', ISTM/2009: 8TH INTERNATIONAL SYMPOSIUM ON TEST AND MEASUREMENT, VOLS 1-6, 8th International Symposium on Test Measure, INTERNATIONAL ACADEMIC PUBLISHERS LTD, Chongqing, PEOPLES R CHINA, pp. 2186-2189.
Husnawan, M, Masjuki, HH, Mahlia, TMI, Saifullah, MG & Kalam, MA 1970, 'The Use of Dihydroxy Fatty Acid and Palm-Based Polyol as Selected Components of Envo-Diesel Fuel Blends to Reduce C.I. Engine Gaseous Emissions and Carbon Deposits', SAE Technical Paper Series, Powertrains, Fuels and Lubricants Meeting, SAE International.
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Nowadays, engine problems such as higher NOx, increase in smoke content and low brake power output due to biofuel fueled engine have been reduced by several improvements by using additives or modifications on engine itself. This paper presents a type of compositions and proper combination of selected chemical components which may be used in palm olein-diesel blends namely "Envo-Diesel". The blended component was designed as an additive package which was blended with diesel-biofuel at 99:1 up to 95:5 percent ratios. Blended fuels with additive have been used in the single cylinder engine which operated under 2000 rpm for 100 hours. Engine performance and emissions tests were conducted as well as engine deposit analysis was done after 100 hours engine operation time. The result was found that by using combined additive engine fuel consumption was decreased about 5%, NOx and SO x emission also reduced about 10% and carbon deposit was found less compared to other fuels especially for higher percentage of additive. Other results such as engine power and CO emission were found quite similar with 100% diesel fuel. These phenomena was shown that by using selected additive in certain amount found to be suitable to reduce diesel engine consumption and exhaust emissions as well as minimizing carbon deposit. Copyright © 2009 SAE International.
Indraratna, B 1970, 'Technical Session 4a: Ground improvement/grouting/dredging', Proceedings of the 17th International Conference on Soil Mechanics and Geotechnical Engineering: The Academia and Practice of Geotechnical Engineering, pp. 3319-3335.
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Indraratna, B, Rujikiatkamjorn, C & Kelly, R 1970, 'Modelling of combined vacuum and surcharge preloading with vertical drains', Proceedings of the 17th International Conference on Soil Mechanics and Geotechnical Engineering: The Academia and Practice of Geotechnical Engineering, pp. 2204-2207.
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In this study, 2D and 3D numerical analyses were conducted to predict embankment behaviour on soft clay foundations stabilised by Combined Vacuum and Surcharge Preloading. To determine the equivalent plane strain permeability, a revised conversion procedure for plane strain condition considering linear permeability variation in the smear zone is proposed. The equivalent permeability coefficients are then incorporated in finite element codes, employing the modified Cam-clay theory. The advantages and limitations of vacuum application through vertical drains are discussed through two selected case histories from China and Australia and the predictions are compared with the available field data. Apart from realistic 3D numerical modelling, it is demonstrated that the equivalent plane strain analysis can now be used as a predictive tool with acceptable accuracy. © 2009 IOS Press.
Indraratna, B, Rujikiatkamjorn, C, Kelly, R & Buys, H 1970, 'Soft Soil Foundation Improved by Vacuum and Surcharge Preloading at Ballina Bypass, Australia', Ground Improvement Technologies and Case Histories, International Symposium on Ground Improvement Technologies and Case Histories, Research Publishing Services, Singapore, SINGAPORE, pp. 95-105.
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Jupp, JR, Eckert, C & Clarkson, PJ 1970, 'DIMENSIONS OF DECISION SITUATIONS IN COMPLEX PRODUCT DEVELOPMENT', ICED 09 - THE 17TH INTERNATIONAL CONFERENCE ON ENGINEERING DESIGN, VOL 3: DESIGN ORGANIZATION AND MANAGEMENT, pp. 239-250.
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Decision-making is a multifaceted phenomenon. Yet in design, many models describing decisionmaking and approaches to decision support are based on simplistic process models and assumptions. This paper reviews the literature surrounding both decision processes and decision support systems, before presenting the authors' own insights from a series of construction and engineering case studies. Based on an analysis of the literature and case study findings, a set of dimensions for classifying factors influencing decision situations is presented. Using this taxonomy the authors then structure the decision process as a dynamic and iterative activity before discussing its implications for decision support systems in design.
Kalam, MA, Masjuki, HH, Mahlia, TMI, Fuad, MA, Halim, K, Ishak, A, Khair, M, Yusoff, A & Shahrir, A 1970, 'Experimental Test of a New Compressed Natural Gas Engine with Direct Injection', SAE Technical Paper Series, Powertrains, Fuels and Lubricants Meeting, SAE International.
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This paper presents experimental test results of a new compressed natural gas direct injection (CNG-DI) engine that has been developed from modification of a multi cylinder gasoline port injection (PI) engine. The major modifications done are (1) the injection system has been modified to gas direct injection using new high pressure gas injectors, (2) compression ratio has been changed from 10 to 14 through modification of piston and cylinder head, and (3) new spark plugs with long edge were used to ignite the CNG fuel. The CNG pressure at common rail was kept at 20 bar to be injected into engine cylinder. The engine has been operated with full throttle conditions to compare all the results with original base engine such as gasoline port injection engine and the CNG bi-fuel engine where the base engine has been converted to bi-fuel injection system to be operated with gasoline and CNG fuels. Hence, it can be mentioned that the original gasoline port injection engine has been modified to CNG bi-fuel and CNG-DI systems. The bi-fuel injection was developed using a gas conversion kit with gas port injection injectors. The test results obtained from CNG fuel using two different systems (i.e. bi-fuel and DI) will be investigated and compared with original gasoline engine. The test was conducted with computer controlled dynamometer to measure brake power, specific fuel consumption (SFC), exhaust emissions such as carbon monoxide (CO), oxides of nitrogen (NOx), and unburned hydrocarbon (HC). The objective of this investigation is to compare the test results between "CNG-DI", with "CNG-BI" and "gasoline - PI" engines with the same displacement volume. It was found that the CNG-DI engine produces 4% higher brake power at 6000 rpm as compared to original gasoline fueled engine. The CNG-BI engine produces maximum power of 57 kW at 5500 rpm which is 23% lower than CNG-DI engine's peak power (at 6000 rpm). The average BSFC of CNG-DI engine was 0.28% and 8% lower than gasoline-P...
Khabbaz, H & Indraratna, B 1970, 'Development of a Smart Tool for Capturing Novel Advancement in Ballasted Rail Track Substructure', Congress e-Proceedings, 8th International Congress on Civil Engineering, International Congress on Civil Engineering, Department Of Civil And Environmental Engineering Of Shiraz University, Shiraz, Iran, pp. 1-8.
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The obligation of keeping a competitive edge against other means of transportation has increased the pressure on the railway industry to improve its efficiency and decrease the maintenance costs. In this paper, several innovative solutions are presented to improve the rail track foundations including optimum particle ballast grading and confining pressure as well as stabilising tracks overlying soft soils employing different techniques. A smart tool for predicting the performance of rail track substructure is also developed. This smart tool provides the user optimum construction parameters and required geotechnical properties according to various subgrade conditions, train loads and speeds.
Manamperi, P, Wije, A, Perumynar, S, Aboura, K, Samali, B & Crews, KI 1970, 'Stochastic Processes for Bridge Deterioration Assessment', 7th Austroads Bridge Conference - Bridges linking communities, 7th Austroads Bridge Conference - Bridges linking communities, Austroads, Auckland, New Zealand, pp. 1-9.
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The Roads and Traffic Authority of NSW (RTA) has over 5000 bridges in the road network under its jurisdiction. These structures were built from different materials, at different times, under different design codes with different articulations and are exposed to different environments. The levels and rate of deterioration of these structures vary greatly and are dependent on the effects of age, environment, magnitude and frequency of heavy traffic and construction quality. These factors make the management of these structures a real challenge to the RTA. In order for the RTA to improve the management of these bridge assets, the RTA is working with the University of Technology Sydney (UTS) to develop a statistical model to predict the future condition of bridges using the condition inspection data collected over the last 15 years. This paper will report on findings of the study conducted to identify a suitable model for prediction of future condition of bridges based on the available inspection data. The gamma process is considered in the development of the predictive model for the life of bridge components. In addition to the gamma process application, observations are made on the distribution of deterioration at different times that could lead to other stochastic processes for modeling time-dependent structural deterioration.
Nguyen, V, Tran, TT, Pham, TL, Vigneswaran, S, Ngo, H, Nguyen, H & Nguyen, DT 1970, 'Use of a Novel Ferrous-Ferric oxide Material from Waste of Iron Ore Mining for Arsenic Removal', The 3rd IWA-ASPIRE Conference & Exhibition (IWA-ASPIRE 2009), The 3rd IWA-ASPIRE Conference & Exhibition (IWA-ASPIRE 2009), IWA, Taiwan, pp. 1-9.
Pradhan, B, Lee, S & Buchroithner, MF 1970, 'GIS application on spatial landslide analysis using statistical based models', SPIE Proceedings, SPIE Europe Remote Sensing, SPIE, pp. 74781B-74781B.
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Raja, S, Stuart, BH & Thomas, P 1970, 'The development of analytical techniques for the determination of forensic bone age', 5th European Academy of Forensic Science Conference Book of Abstracts, 5th European Academy of Forensic Science Conference, Glasgow, pp. 1-1.
Raja, S, Thomas, P & Stuart, BH 1970, 'A study of storage conditions and treatments for forensic bone specimens using thermogravimetric analysis', Medicta 2009 Book of Abstracts, 9th Mediterranean Conference on Calorimetry and Thermal Analysis, Marseille.
Raja, S, Thomas, P, Stuart, BH & O'Brien, C 1970, 'Pyrolysis gas chromatography - mass spectrometry analysis for the estimation of pig bone age', 21st Congress of the International Academy of Legal Medicine Abstracts, Congress of the International Academy of Legal Medicine, Lisbon.
Ray, AS, Connan, H, Liu, B & Thomas, P 1970, 'Alumina-Silica Rich Clay Brick Waste In Hydrothermally Treated Cement-Based Construction Products', Proceedings of the 34th Conference on Our World In Concrete & Structures, Conference On Our World In Concrete & Structures, CI-Premier Conference Organisation, Singapore, Singapore, pp. 289-296.
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An urgent need for creative, sustainable approaches, which minimise the environmental impact of conventional Portland Cement (PC) -based construction materials, is recognised throughout the world. In recent years intensive research has been directed to the use of alumino-silicate materials to produce blended PC. The reduction of CO2 emissions, through the minimisation of PC consumption in the manufacture of PC-based construction products, and utilisation of industrial byproducts, to limit environmental impact, are the principal drivers of this worldwide activity. A number of supplementary cementitious materials (SCMs) containing alumina and silica such as fly ash, granulated blast furnace slag and silica fume are well known additives for the production of blended PCs due to their pozzolanic properties. The potential of other by-products such as those from the construction and demolition industry are less known however, even though they represent an excellent source of reactive alumina and silica-rich material. This paper deals with fired clay bricks (CB), generated as a waste product from construction and demolition activities, and their value as an additive in the manufacture of PC-based construction products. The research findings reported in this paper are from laboratory scale experiments conducted under hydrothermal conditions in an autoclave where fmely ground Cl3 waste was incorporated in the mixes. From a combination of analytical techniques including X-ray Diffraction, Differential Thermal Analysis, Scanning Electron Microscopy and solid-state Nuclear Magnetic Resonance, it was established that the aluminosilicate phase in the fired clay bricks promoted the development of the tobermorite, the principal binder in most calcium silicate products under hydrothermal conditions. The use of CB waste as a cement replacement for the manufacture of these products was also demonstrated as a viable option.
Regmi, G, Indraratna, B & Nghiem, LD 1970, 'Long-term Performance of a Permeable Reactive Barrier in Acid Sulphate Soil Terrain', Water, Air, & Soil Pollution: Focus, Springer Science and Business Media LLC, pp. 409-419.
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Deep drainage technique utilised for flood mitigation in low-land coastal areas of Australia during the late 1960s has resulted in the generation of sulphuric acid in soil by the oxidation of pyritic materials. Further degradation of the subsurface environment with widespread contamination of the underlying soil and groundwater presents a major and challenging environmental issue in acid sulphate soil (ASS) terrains. Although several ASS remediation techniques recently implemented in the floodplain of Southeast Australia including operation of gates, tidal buffering and lime injections could significantly control the pyrite oxidation, they could not improve the long-term water quality. More recently, permeable reactive barriers (PRBs) filled with waste concrete aggregates have received considerable attention as an innovative, cost-effective technology for passive in situ clean up of groundwater contamination. However, long-term efficiency of these PRBs for treating acidic groundwater has not been established. This study analyses and evaluates the performance of a field PRB for treating the acidic water over 2.5 years. The pilot-scale alkaline PRB consisting of recycled concrete was installed in October 2006 at a farm of southeast New South Wales for treating ASS-impacted groundwater. Monitoring data of groundwater quality over a 30 month period were assessed to evaluate the long-term performance of the PRB. Higher pH value (∼pH 7) of the groundwater immediately downstream of the PRB and higher rates of iron (Fe) and aluminium (Al) removal efficiency (>95%) over this study period indicates that recycled concrete could successfully treat acidic groundwater. However, the overall pH neutralising capacity of the materials within the barrier declined with time from an initial pH 10.2 to pH 7.3. The decline in the performance with time was possibly due to the armouring of the reactive material surface by the mineral precipitates in the form of iron and aluminium hydroxi...
Retallick, ME, Babister, KM, Varga, C, Ball, JE & Askew, E 1970, 'Do Filtered Temporal Patterns Resemble Real Patterns?', Proceedings of H2009 the 32nd Hydrology and Water Resources Symposium, Hydrology and Water Resources Symposium, Engineers Australia, Newcastle, Australia, pp. 135-145.
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Since publication of ARR87, available computer resources have increased thus enabling the analysis of a pluviograph record. This analysis typically involves extracting the significant storm events and determining the temporal patterns of these storms. These extracted temporal patterns will then be scaled for the design rainfall depth and filtered if necessary. Presented herein are the results of a study into the observed and filtered temporal patterns derived from the Sydney Observatory Hill pluviograph record. It was found that filtering changed the ranking of periods within the storm, changed the depth of antecedent rainfall prior to the intense part of the rainfall event, and changed the percentage of the storm occurring in the core of the storm (most intense part of the storm). Furthermore, if aggressive filtering of the observed temporal pattern is required, the user is probably better to not filter at all as the pattern will no longer resemble the original pattern.
Sakal, A, Ball, JE & Smith, GP 1970, 'Sydney catchment authoritys' real-time flow forecasting system mike flood watch', The International Conference of Science and Information Technology for Sustainable Management of Aquatic Ecosystems, International Conference on Hydroinformatics, Universidad de Concepcion, Chile, pp. 1-7.
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Australia is one of the driest inhabited continents on earth. Water has been vital to the survival and prosperity of Sydney. The need to ensure a reliable water supply through times of drought and erratic seasonal rainfall has driven the development of several complex and innovative water supply schemes. The Sydney Catchment Authority (SCA) protects five catchment areas where water is collected by natural landscape to provide water for Sydney and manages 21 dams, total area of 16000 square kilometres. Management and operation of the storages is a complex process. Operational decisions affecting the management of the storages are made on a daily basis and require accurate and up-to-date information. The SCA uses GIS based real-time flow monitoring and in-flow forecasting system aimed to provide baseline information for supporting the daily operation of the storages. A key feature of the systemâs success has been the ability to integrate existing hydrologic models and automate their operation with measured data real-time to produce real time forecasts of catchment inflows. The real-time flow forecasting system is under ongoing improvement. Shortly it will be configured with a fully distributed hydrological model which will be fed with real-time radar derived rainfall estimates and 36 hours rainfall forecast from MezoLAPS climate model to provide 36 hours flow forecasts.
Sheng, D & Fredlund, DG 1970, 'An elastoplastic model for unsaturated soils', Proceedings of the 17th International Conference on Soil Mechanics and Geotechnical Engineering: The Academia and Practice of Geotechnical Engineering, pp. 3403-3407.
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A number of elastoplastic models have been proposed for unsaturated soils over the past three decades. These models have generally taken the form of simple extensions of elastoplastic models previously proposed for saturated soils. Laboratory testing programs have given rise to several unanswered questions regarding the acceptability of these models for unsaturated soils. There are questions related to: 1.) the variation of the yield stress with soil suction, 2.) the modeling of soils prepared from slurry conditions, and 3.) the existence of a smooth transition between saturated and unsaturated soil conditions. The model proposed in this paper addresses each of these questions by re-formulating the elastoplastic model for unsaturated soils through use of independent stress state variables. The re-formulation provides a smooth transition between the elastoplastic model for saturated and unsaturated soil conditions. © 2011 IOS Press.
Thakur, PK, Indraratna, B & Vinod, JS 1970, 'DEM simulation of effect of confining pressure on ballast behaviour', Proceedings of the 17th International Conference on Soil Mechanics and Geotechnical Engineering: The Academia and Practice of Geotechnical Engineering, pp. 602-605.
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In this paper, an attempt has been made to investigate the influence of confining pressure on deformation and degradation behaviour of railway ballast using the Discrete Element Method (DEM). A novel approach has been employed to model the two dimensional projection of field size ballast particles as cluster of bonded particles. Bonded particles are held together by a bond, and debonding is considered as particle breakage. A series of cyclic loading simulations using DEM were carried out on an assembly of angular ballast particles at different confining pressures (10 kPa to 240 kPa). The results highlight that the development of axial strain during cyclic loading as a function of initial confining pressure and number of cycles. Very high axial strain and breakage of particles have been observed at low confining pressure (< 30 kPa) owing to dilative volumetric strain behaviour. In terms of particle breakage, there exists an optimum range of confining pressures where breakage is minimal. In addition, the evolution of particle displacement vectors explains the breakage mechanism and associated deformations during cyclic loading. © 2009 IOS Press.
Varga, C, Ball, JE & Babister, M 1970, 'A hydroinformatic approach to development of design temporal patterns of rainfall', IAHS-AISH Publication, Hydroinformatics in Hydrology, Hydrogeology and Water Resources, IAHS Publication 331, Hyderabad, India, pp. 20-29.
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Estimation of the design rainfall for design flood estimation remains a problem for many engineering hydrologists despite many research studies into appropriate methodologies. An important aspect of flood flow estimation through catchment simulation is the design rainfall. Presented herein is a new approach for estimation of the temporal pattern of rainfall during a hypothetical design storm. The basis of the approach is a conditional random walk in non-dimensional space to create a finite number of storm patterns based on the probability that the storm event is convective or frontal and the probability that the storm centre of mass is located at the beginning, middle, or end of the storm event It is shown that the resultant storm patterns more closely reflect historical patterns man alternative methods for estimating the design temporal pattern of rainfall. Copyright © 2009 IAHS Press.
Vessalas, K, Ray, AS, Thomas, P, Joyce, PA & Haggman, J 1970, 'Assessment of chemical durability of pitchstone fines in Portland cement blended mortars', Concrete Solutions 09: Adding value in changing climates - Proceedings of the 24th Biennial Conference of the Concrete Institute of Australia, Concrete Solutions 09: Adding value in changing climates - 24th Biennial Conference of the Concrete Institute of Australia, Concrete Institute of Australia, Sydney, Australia, pp. 1-9.
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The use of supplementary cementitious materials (SCMs) as partial replacement of Portland cement (PC) is an effective way of reducing the consumption of PC. This investigation is aimed at assessing some chemical durability aspects of PC-SCM blended mortars containing pitchstone fines (PF) and fly ash (FA) at 20% and 40% replacement levels of PC. Hardened mortar cubes containing these two pozzolanic SCMs and a control mortar containing 100% PC were prepared and pre-aged in lime-saturated water for 28-days. These specimens were then immersed into 1M solution of sodium sulphate (Na2SO4) and their mass and pH recorded after 28-days and 56-days. Specimens were also immersed in deionised water as a control environment for comparison of mass change and pH. In the case of PF, data from 1M Na2SO4 immersion demonstrate increasing substitution rate provides lower mass gain. In contrast, increasing replacement rate of PC by FA in 1M Na2SO4 demonstrates higher mass gain comparable to 100% PC.
Vinod, JS, Indraratna, B & Mahamud, MAA 1970, 'Internal Erosional Behaviour of Lignosulfonate Treated Dispersive Clay', Ground Improvement Technologies and Case Histories, International Symposium on Ground Improvement Technologies and Case Histories, Research Publishing Services, Singapore, SINGAPORE, pp. 549-554.
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Wang, J & Duan, H 1970, 'Learning Dynamic System Oriented Model Based Programming', 2009 IEEE International Symposium on IT in Medicine & Education, Education (ITIME), IEEE.
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Wang, J, He, X & Xu, S 1970, 'Real-Time Adjusting of Yaw Angle of Space Camera Based on General Image-Quality Equation', 2009 Second International Conference on Intelligent Computation Technology and Automation, 2009 Second International Conference on Intelligent Computation Technology and Automation, IEEE.
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Wang, JJ, Hu, G, Huang, S & Dissanayake, G 1970, '3D landmarks extraction from a range imager data for SLAM', Proceedings of the 2009 Australasian Conference on Robotics and Automation, ACRA 2009, Australasian Conference on Robotics and Automation, Australian Robotics and Automation Association Inc., Sydney, Australia, pp. 1-8.
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This paper introduces a new 3D landmark extraction method using the range and intensity images captured by a single range camera. Speeded up robust features (SURF) detection and matching is used to extract and match features from the intensity images. The range image information is used to transfer the selected 2D features into 3D points. The range measurement bias and uncertainty of the range camera are analysed, and their models are developed for improving the range estimation. After outliers' detection and removal using random sampling consensus (RANSAC), reliable 3D points are obtained. 3D landmarks for simultaneous localisation and mapping (SLAM) are selected from the 3D points considering several factors, such as the uncertainty and geometry of their locations. Because of the availability of the SURF descriptor, the data association in SLAM has been performed using both the geometry and the descriptor information. The proposed method is tested in unstructured indoor environments, where the range camera moves in six degrees of freedom. Experimental results demonstrate the success of the proposed 3D landmark extraction method for SLAM.
Wang, JJ, Kodagoda, S & Dissanayake, G 1970, 'Vision aided GPS/INS system for robust land vehicle navigation', 22nd International Technical Meeting of the Satellite Division of the Institute of Navigation 2009, ION GNSS 2009, pp. 195-204.
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This paper introduces a new approach for improving land vehicle navigation by integrating a digital camera with a GNSS receiver and a MEMS INS, to provide seamless robust navigation solutions in urban environment. As a camera has the ability to detect surrounding environment, it can measure its relative position and direction to the surrounding objects. The integration of heterogeneous sensors with very different characters, such as GNSS, INS and image in this approach, can complement each other and provide cost-effective and robust navigation solutions. In the proposed system, INS is selected as the reference navigation sensor as it provides complete navigation solutions without disruptions. The navigation errors caused by its inherent nonlinear and time-varying characteristics can be corrected by the camera and GNSS. Vision based navigation (VBN) is one of the fundamental issues in computer vision and is relatively well developed. In this paper mono vision (MV) based navigation technologies are merged with GNSS and INS measurement, termed as GNSS/INS/MV (GlMV) integration. VBN is at the core of proposed robust navigation system, in which a relative range scale factor is estimated by continuously applying structure-from-motion in the MV navigation. Due to the complexity of multi-sensor integration, it needs an optimal sensor fusion framework with reliable system design, modeling and quality control procedures. The proposed sensor fusion method consists of two local and one master data fusion units, based on extended Kalman filter and fuzzy logic. It takes the advantages of federate architecture, and can select using either GNSS or VBN navigation solutions for PNS correction according to their quality. GNSS/INS integration is the mainstream for navigation when the vehicle travels in an open area with good GNSS signal. At the same time, the modeling parameters of INS and camera are estimated. When the system is navigating in areas with weak GNSS signals,...
Wu, C & Lok, TS 1970, 'Preface', Proceedings of the 8th International Conference on Shock and Impact Loads on Structures.
Wu, C, Huang, L, Oehlers, DJ & Kuznetsov, VA 1970, 'Experimental study of reinforced concrete slabs protected with aluminum foam under blast loading', Proceedings of the 8th International Conference on Shock and Impact Loads on Structures, pp. 709-714.
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Aluminum foam is a novel lightweight material that has many excellent plastic mechanical properties. Application of aluminum foam as a sacrificial cladding on the bearing face of retrofitted structures could enhance the resistance capacities of structures against impact or blast loading. The aluminum foam undergoes great plastic deformation under transient dynamic loads before becoming fully densified, thus absorbing blast energy. In order to investigate the blast mitigation effect of aluminium foams, three 2000 × 1000 × 100 mm reinforced concrete (RC) slabs retrofitted with 12.7 mm, 25 mm and 43.2 mm thick aluminum foam sheets with densities of 450 kg/m3, 450 kg/m3 and 140 kg/m3, respectively, were subjected to explosive blast loads. The incident pressures of the blast loads, the deflections at the mid-span of the specimens were measured. A control sample of an un-retrofitted RC slab was loaded by blasting under similar conditions. It has been found that the RC slab that was covered with a 25 mm thick foam sheet reached a maximum dynamic deflection of 22mm, which is 43% less than the 38.9 mm deflection of the unretrofitted slab, while the slab overlaid with the 43.2 mm thick foam sheet experienced a maximum dynamic deflection of 31mm.
Wu, C, Oehlers, DJ, Rebentrost, M & Leach, J 1970, 'Energy-Controlled Design of Reinforced Ultra-High Performance Fiber Concrete Slabs against Airblast Loads', Key Engineering Materials, 2nd International Conference on Advances in Concrete and Structures, Trans Tech Publications, Ltd., Changsha, PEOPLES R CHINA, pp. 107-112.
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Displacement-controlled design method is now being used by current guidelines such as TM5 and ASCE to design RC members against airblast load. If the maximum deflection of the designed member under airblast loads is less than the allowable deflection, the designed member is considered to be safe. Although the displacement-controlled design method is easy to use, it may not result in a design having maximum energy-absorption capacity against airblast loads, especially for a design of a reinforced ultra-high performance fibre concrete (RUHPFC) member which is of both high strength and high ductility, that is, high energy-absorption capacity. In this paper, a layered analysis model allowing for varying strain rates with time as well as along the depth of the member was used to calculate energy-absorption of a simple supported RUHPFC slab under airblast loads. An optimal reinforcement ratio of the slab was achieved by maximizing the energy absorption of the slab under different reinforcement ratios. The energy-controlled design method was validated by field blast tests. Using the validated design method, a designed slab with the optimal reinforcement ratio was also tested and the effectiveness of the design was demonstrated.
Wu, C, Ozbakkloglu, T, Huang, ZY & Ma, G 1970, 'Experimental investigation of FRP confined reinforced concrete under impact loads', Proceedings of the 8th International Conference on Shock and Impact Loads on Structures, pp. 715-719.
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Buildings and infrastructure may experience extreme circumstances such as terrorist bomb attacks, missile attacks and vehicle collisions and their key structural members, such as columns, could be shattered, leading to the collapse of the whole building and a large number of injuries and casualties. To protect these buildings and infrastructure against extreme loading, it is necessary to strengthen key structural components using advanced retrofit technologies. Recent research has demonstrated that FRP-confined concrete can significantly enhance structural members' strength and ductility under static loads and it is expected that this retrofit can also used to strengthen structural components under the impact and blast loads. In this paper, FRP tubes are used to confine concrete columns externally. A comprehensive experimental program was conducted to investigate the behaviour of normal strength of circular concrete specimens confined with FRP. The test program included a number of confined cylindrical concrete specimens under static loading, hammer dynamic loading and Split Hopkinson Pressure Bar impact loading (SHPB). The size of the specimens, and number of CFRP layers on the influence of the confinement effectiveness of FRP tubes are investigated. The recorded data can be used for validating numerical modeling in the further studies.
Wu, C, Ozbakkloglu, T, Ma, G & Huang, ZY 1970, 'Numerical Simulation of Performance of Concrete-Filled FRP Tubes Under Impact Loading', Analysis of Discontinuous Deformation — New Developments and Applications, 9th International Conference On Analysis of Discontinues Deformation: New Developments and Applications, Research Publishing Services, Nanyang Technol Univ, Singapore, SINGAPORE, pp. 675-684.
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Wu, C, Wu, C, Chen, W & Oehlers, DJ 1970, 'Analysis of Retrofitted RC Beam with Fixed End Supports against Blast Loads', Key Engineering Materials, 2nd International Conference on Advances in Concrete and Structures, Trans Tech Publications, Ltd., Changsha, PEOPLES R CHINA, pp. 795-800.
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Currently, there are adequate guidelines available for FRP retrofitting RC structures against static and seismic loads. However, there is still limited information on retrofitting RC structures against short-duration dynamic loading effects such as blast loading. Due to the increasing threat of terrorism in recent years, retrofitting of RC structures against blast loading is of paramount importance in structural engineering. In this paper, a dynamic model that is based on single-degree-of-freedom (SDOF) approach is developed for the analysis of the response of retrofitted fixed end supported RC slabs subjected to blast loads. A previously validated layered capacity analysis method is used to determine the yielded and ultimate blast resistant capacity of a cross-section of a RC slab which allows varying strain rates with time along the depth of the member. The corresponding deflections are determined by plastic hinge analysis. To simplify the calculation process, a tri-linear resistance-deflection function which consists of elastic, elasto-plastic and plastic region for fixed end supported RC slabs is converted to an equivalent bilinear function. This developed model can adequately predict the retrofitted members’ response to blast loading. It is then is used to conduct a parametric study to optimise the retrofitting of RC slabs subjected to blast loading by varying the quantity, material type and technique of retrofitting.
Zhang, J, Xu, YL, Xia, Y & Li, JC 1970, 'Statistical moment-based damage detection of building structures', Structural Health Monitoring of Intelligent Infrastructure - Proceedings of the 4th International Conference on Structural Health Monitoring of Intelligent Infrastructure, SHMII 2009.
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This paper presents a novel structural damage detection method based on the statistical moments of dynamic responses of building structures under random excitation. The principle of the method is put forward in terms of a single-degree-of-freedom (SDOF) system and then extended to multi-degree-of- freedom (MDOF) systems with resort to the least-squares method. The numerical studies on a shear building structure manifest that the proposed method is sensitive to local structural damage but insensitive to measurement noise. Furthermore, the proposed method was experimentally examined to assess its reliability in practical applications. Eight damage scenarios were designed and a series of shaking table tests were conducted on three shear building models before and after damage under white noise or color noise ground excitations. The experimental results matched the theoretical values well and the statistical moment-based damage detection method is demonstrated to be feasible and accurate.
Zhu, XQ & Hao, H 1970, 'Condition assessment of prestressed concrete structures with static and dynamic damage indexes', Concrete Repair, Rehabilitation and Retrofitting II - Proceedings of the 2nd International Conference on Concrete Repair, Rehabilitation and Retrofitting, ICCRRR, 2nd International Conference on Concrete Repair, Rehabilitation and Retrofitting, CRC PRESS-TAYLOR & FRANCIS GROUP, Cape Town, SOUTH AFRICA, pp. 259-260.
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This paper studies the feasibility of using changes in the static and dynamic properties of the prestressed concrete structures under static loads to detect damage. An experimental study is carried out on a prestressed concrete beam of Tee cross section subjected to the static loads. The crack damage is created by applying the four point loads on the beam. A static damage index, based on the flexural rigidity of the beam, is proposed for condition assessment of the prestressed concrete beam structures under static loads. A dynamic damage index based on the change of the natural frequency is also proposed. Experimental results show that the two indexes are effective to detect the damage in prestressed concrete structures. Unlike results obtained for structures of isotropic and homogeneous materials, the identified damage level of the current prestressed concrete beam is found dependent on the static load it carries. This implies that the prestress reduces the crack damage in a prestressed concrete beam after the applied load is removed. © 2009 Taylor & Francis Group.
Zhu, XQ, Hao, H, Fan, KQ, Wang, Y & Ou, JP 1970, 'Debond detection in RC structures using piezoelectric materials', Concrete Repair, Rehabilitation and Retrofitting II - Proceedings of the 2nd International Conference on Concrete Repair, Rehabilitation and Retrofitting, ICCRRR, 2nd International Conference on Concrete Repair, Rehabilitation and Retrofitting, CRC PRESS-TAYLOR & FRANCIS GROUP, Cape Town, SOUTH AFRICA, pp. 261-262.
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This paper presents a new technique to detect the delamination between the steel bars and concrete in the reinforced concrete structures. The piezoelectric components are mounted on reinforcing bars that are embedded in RC structures as sensors and actuators to generate and record the signal, which is sensitive to the delamination between the steel bars and concrete. The experimental study is carried out on a concrete slab with different debonds between the rebars and concrete. The test results show that the delamination between the rebars and concrete can be detected with the embedded piezoelectric sensors and actuators. © 2009 Taylor & Francis Group.