BALL, JE 1994, 'THE INFLUENCE OF STORM TEMPORAL PATTERNS ON CATCHMENT RESPONSE', JOURNAL OF HYDROLOGY, vol. 158, no. 3-4, pp. 285-303.
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Briscoe, BJ & Thomas, PS 1994, 'Friction Energy Dissipation in Organic Films', Tribology Series, vol. 27, no. C, pp. 193-202.
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The paper speculates upon the molecular relaxation and dissipation mechanisms which may be responsible for the interface Theological characteristics of thin organic films. The molecular structure and interface rheology of a homologous series of poly(n-alkyl methacrylate)s are characterised for this purpose. These Theological properties are identified by the measurement of the interface shear strength, t as a function of the contact pressure. The molecular structure is deduced using vibrational spectroscopy. The Eyring model for molecular plastic flow is then applied and a correlation is drawn between the Theological and structural properties which are discussed in terms of possible mechanisms for the dissipation of the frictional energy. © 1994, Elsevier Inc. All rights reserved.
CAO, HT, BUCEA, L & SIRIVIVATNANON, V 1994, 'INFLUENCE OF BINDER TYPE ON ANODIC-DISSOLUTION OF STEEL EMBEDDED IN CEMENT PASTES', CEMENT AND CONCRETE RESEARCH, vol. 24, no. 2, pp. 203-213.
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Indraratna, B 1994, 'Geotechnical characterization of blended coal tailings for construction and rehabilitation work', Quarterly Journal of Engineering Geology, vol. 27, no. 4, pp. 353-361.
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Coarse and fine refuse is produced by various coal processing equipment. The relatively wet fine tailings have limited use in construction activities and they are generally pumped as slurries into tailings ponds. The coarse rejects have a greater engineering applicability and are utilized in the construction of tailings dams and mine access roads as well as for landfill and ballast. This study investigates the fundamental engineering properties of blended tailings, whereby appropriate fractions of flotation tailings are mixed with cyclone rejects to produce an acceptable construction or rehabilitation fill. In particular, a practical procedure to optimize the blended ratios, is proposed on the basis of fundamental geotechnical testing. The applications of relevent tests are described, including Proctor compaction, California Bearing Ratios, triaxial and consolidation tests. The results confirm that blending of fines with coarse rejects enables enhanced dry densities associated with reduced permeabilities, higher shear and compressive strengths, lower consolidation settlements and increased bearing capacities. The addition of a small quantity of cement (2-5%) further improves the engineering properties of the blended matrix. -from Author
Indraratna, B 1994, 'The effect of normal stress-friction angle relationship on the stability analysis of a rockfill dam', Geotechnical and Geological Engineering, vol. 12, no. 2, pp. 113-121.
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Accurate stability analysis must consider the variation of the angle of friction of rockfill with the confining pressure. In reality, with increasing depth of a rockfill dam, the apparent friction angle decreases, whereas near the surface it tends to be higher. Conventional methods which employ a constant friction angle throughout the depth of a rockfill shell often yield a lower factor of safety (conservative) for shallow slip planes. On the contrary, they produce a higher factor of safety for deepseated slips subjected to increased normal (confining) stresses. This paper compares the constant friction angle approach with the variable friction angle method based on the stability analysis of a large rockfill dam, and the associated practical implications are discussed. In the latter analysis, the effect of normal stress on the friction angle of rockfill is incorporated through experimental observations. © 1994 Chapman & Hall.
Indraratna, B, Balasubramaniam, AS & Ratnayake, P 1994, 'Performance of Embankment Stabilized with Vertical Drains on Soft Clay', Journal of Geotechnical Engineering, vol. 120, no. 2, pp. 257-273.
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Indraratna, B, Gasson, I & Chowdhury, RN 1994, 'Utilization of compacted coal tailings as a structural fill', Canadian Geotechnical Journal, vol. 31, no. 5, pp. 614-623.
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Detailed laboratory investigations were conducted on coal tailings produced at Westcliff Colliery, New South Wales, Australia. Geotechnical tests were conducted to determine the particle-size distribution, mineralogy, compaction characteristics, compressive strength (California bearing ratio), shear resistance, and collapse potential. The tests show that compacted tailings have good potential as effective fill for embankments, tailings dams, mine access roads, and pavements. Large-scale utilization of these tailings for rehabilitation of subsidence-affected areas and mine backfill is particularly encouraging. It is demonstrated that this waste material can be efficiently compacted to produce acceptable engineering properties over a wide range of water contents. Although the behaviour of one specific type of tailings cannot be generalized to the diverse composition of other coal tailings, the results of this study assist in the interpretation of geotechnical data associated with nonconventional fill. The use of geotextiles in the stabilization of tailings is presented. The effect of moisture content and the number of geotextile layers on the shear strength parameters is investigated, and the influence of geotextiles on the failure modes of triaxial specimens is also discussed. Key words : California bearing ratio, coal tailings, compaction, geotextiles, structural fill, triaxial testing.
Indraratna, B, Wijewardena, LSS & Balasubramaniam, AS 1994, 'Discussion: Large-scale triaxial testing of greywacke rockfill', Géotechnique, vol. 44, no. 3, pp. 539-543.
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LOGANATHAN, P, HEDLEY, MJ & BRETHERTON, MR 1994, 'THE AGRONOMIC VALUE OF CO-GRANULATED CHRISTMAS ISLAND GRADE-C PHOSPHATE ROCK AND ELEMENTAL SULFUR', FERTILIZER RESEARCH, vol. 39, no. 3, pp. 229-237.
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Certain low grade phosphate rocks have low agronomic value as direct applied fertilizers and make poor quality superphosphates. With some rocks there is potential to increase their solubility in soils and hence the fertilizer value by mixing with finely divided elemental sulphur (S°). The agronomic value of a prototype 'low cost', granular P and S fertilizer, Christmas Island Grade C phosphate rock/elemental sulphur (Xmas C/S°), was compared against single superphosphate (SSP) and reactive phosphate rock (RPR)/S° dry blends, North Carolina phosphate rock/S° (NCPR/S°) and NCPR/50% S-super (granular SSP + 44% S°). An eight- month glasshouse trial using ryegrass (Lolium perenne L. cv. Nui), grown in a central yellow-grey earth (Aeric Fragiaqualf), indicated that fertilization with Xmas C/S° produced dry matter yields, between 54 to 73% and 10 to 40% lower than SSP and NCPR/S° blends respectively, and lower plant P and S uptake. Fertilization with Xmas C/S° however produced significantly higher yield and P and S uptake than unfertilized pots and pots receiving Xmas C PR and S° alone. The two RPR/S° dry blends, namely NCPR/S° and NCPR/50% S-super, produced significantly lower yield and P and S uptake than the same two fertilizers granulated with water. The difference in yields and P and S uptake between blends and granulated forms increased with time. The recovery of fertilizer P and S by plants ranged from 3 to 35% and 2 to 45% respectively with the lowest recoveries for Xmas C PR alone and S° alone and the highest for SSP and SSP + S°. During the period of plant growth the percentage of S° oxidised from the S°, Xmas C/S° co-granule, NCPR/S° physical blend and NCPR/S° granular treatments were 37, 32, 32 and 45% respectively. Field evaluations, or use, of the co-granule should consider it's slow P and S release rates. © 1994 Kluwer Academic Publishers.
Zhou, JL, Rowland, S, Fauzi, R, Mantoura, C & Braven, J 1994, 'The formation of humic coatings on mineral particles under simulated estuarine conditions—A mechanistic study', Water Research, vol. 28, no. 3, pp. 571-579.
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BABISTER, KM, BALL, JE & INST ENGINEERS, A 1970, 'A REVIEW OF NUMERICAL PROCEDURES FOR ROUTING UNSTEADY FLOWS ALONG A DRY BED', 1994 INTERNATIONAL CONFERENCE ON HYDRAULICS IN CIVIL ENGINEERING - HYDRAULICS WORKING WITH THE ENVIRONMENT, PREPRINTS OF PAPERS, 1994 International Conference on Hydraulics in Civil Engineering - Hydraulics Working with the Environment, INST ENGINEERS AUSTRALIA, UNIV QUEENSLAND BRISBANE, BRISBANE, AUSTRALIA, pp. 43-48.
Ball, JE, Hogan, PM, Batley, GE & Brockbank, C 1970, 'Assessing the quantity and quality of stormwater runoff from road surfaces', National Conference Publication - Institution of Engineers, Australia, pp. 299-304.
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The community is concerned about many aspects of the aquatic environment. Recently the focus of this attention has been the contamination of water bodies arising from stormwater runoff. Discussed herein is a project currently being undertaken by the Department of Water Engineering of the School of Civil Engineering at the University of New South Wales and the Centre for Advanced Analytical Chemistry, CSIRO which is studying stormwater runoff from road surfaces. A particular focus of this study is development of an understanding of the removal of heavy metal pollutant constituents such as Pb, Cu, Zn. A review of available data concluded that insufficient data were available to enable the processes involved to be understood and hence there was a need to establish a field gauging station specific to this problem. Presented in this paper are some details of the field gauging station installed as part of this project and some preliminary information obtained from it.
BAWEJA, D, SIRIVIVATNANON, V, GROSS, W & LAURIE, G 1970, 'High-performance Australian concretes for marine applications', HIGH-PERFORMANCE CONCRETE - PROCEEDINGS, ACI INTERNATIONAL CONFERENCE, ACI International Conference on High-Performance Concrete, AMER CONCRETE INST, SINGAPORE, SINGAPORE, pp. 363-377.
Cao, HT, Bucea, L, Wortley, BA & Sirivivatnanon, V 1970, 'Corrosion behaviours of steel embedded in fly ash blended cements', American Concrete Institute, ACI Special Publication, pp. 215-227.
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In this paper corrosion characteristics of steel embedded in hardened cement pastes and mortars were investigated by using data obtained from potentiodynamic anodic polarization and polarization resistance techniques. One normal portland cement and one fly ash were used. The dosages of fly ash as cement replacement material were 0, 20, 40 and 60 percent. The results indicate that there was no negative effect of pozzolanic reaction of fly ash on steel passivation even at a high replacement dosage of 60 percent and after 2 years of curing. In fact, with prolonged curing, steel embedded in fly ash blended cement pastes was found to have higher degree of passivation with greater stability than that embedded in plain cement paste. Chloride binding capacity of 40 percent fly ash blended cement paste as indicated by the measured corrosion rate of steel was found to be very effective after 3 days of curing. In accelerated carbonation condition, corrosion rates of steel were initially high in fly ash blended cement mortars. When fully carbonated, the results indicate that the corrosion rate of steel can be higher in plain cement in comparison to 40 percent flyash blend. In the case of chloride penetration, the corrosion rate of steel was found to be consistently less than that of equivalent plain cement when compared on equal water-to-binder ratio.
Roper, H, Sirivivatnanon, V & Baweja, D 1970, 'Long-term performance of portland and blended cement concretes under morine conditions', American Concrete Institute, ACI Special Publication, pp. 331-351.
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Specifications relating to concrete durability have been emphasised in many recent codes of practice governing the design of concrete structures. Typical examples of this trend are noted in Australian Standard AS 3600, British Standard BS 8110 and a Guide to Durable Concrete reported by ACI Committee 201. Apart from the requirements of higher strength grades to ensure required minimum water: Cement ratios for aggressive environment exposures, some advantages offered by the use of blended cements have been recognised in these documents. The use of blended slag and fly ash cements is increasing worldwide and specific information on the long-term performance of such concretes in high chloride environments is needed. This paper presents data on the long-term corrosion characteristics in high chloride environments of reinforcement within a series of concretes individually incorporating a high C3A ordinary portland cement, a low C3A cement, a slag blended cement and an ASTM Class F fly ash blended cement. The concrete performance has been assessed using electrochemical monitoring of corrosion of the embedded reinforcement by potentiodynarnic anodic polarisation and the concrete resistivity. Factors that significantly influence the corrosion rate of the reinforcement include the concrete water: Binder ratio, the binder type and the resistivity. Comments are made regarding current North American, British and Australian specifications for concrete under marine service conditions. From the data presented, the specification for long-term durability of concrete for marine conditions could be based on concrete resistivity with a suggested limit of around 5000 ohm cm at 28 days.
Sirivivatnanon, V, Trinh Cao, H & Nelson, P 1970, 'Mechanical and durability properties of high volume fly ash concrete', American Concrete Institute, ACI Special Publication, pp. 967-984.
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In this study, structural grade concretes with characteristic strength of 20 to 45 MPa were made with general purpose portland cement (ASTM Type I} and with fly ash blends. High volumes of fly ash (ASTM Class F) in the range of 40-50 percent by weight of total binder were used. It was found that for an equivalent 28-day strength and slump, structural concretes containing high volume fly ash can provide a number of advantages over plain cement concretes including lower drying shrinkage and better creep characteristics. Similar flexural strength and elastic modulus were observed between equivalent plain cement and high volume fly ash concretes. Experience obtained in field trials of high volume fly ash concretes showed that they can be mixed, transported, placed and finished using conventional concreting equipment and technique. Laboratory studies of blended cements containing high percentages of fly ash as cement replacement material indicated that steel passivation characteristics improved with age of hydration and there was no negative effect caused by pozzolanic reaction. Electrochemical data using polarization resistance techniques on paste samples immersed in 0.5 M NaCl solution are given. The results indicated that even with limited initial curing of 7 days, the corrosion rates of steel in 40 wt% fly ash blend were very similar to that of plain cement at high water-to-binder ratio (>0.6) and were lower than that of plain cement at low water-to-binder ratio ( <=0.6). Data obtained from mortar samples subjected to sulphate environments suggested that the use of blended cements with high fly ash replacement could be beneficial in the case where the pH of the environment was low such as that experienced by concrete structures in sewerage works.
Zaman, S & Ball, JE 1970, 'Simulation of small events in an urban catchment', National Conference Publication - Institution of Engineers, Australia, pp. 353-358.
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In general, stormwater runoff from an urbanised catchment is the result of a complex interaction of processes which influence the generation of rainfall on both the pervious and impervious areas within the catchment. When the rainfall depth is small, however, the rainfall excess will be generated primarily on the impervious surfaces with a consequent reduction in the complexity of the interaction of the processes. To investigate the processes influencing the generation of rainfall excess and, hence, the development of stormwater runoff, a number of storm events with small rainfall depths were simulated on the Salt Pan Creek catchment. Presented herein are the results obtained from these simulations. Also presented is a discussion of the interaction between alternative processes occurring on impervious surfaces.
