Publications

Fatahi, B, Khabbaz, H & Fatahi, B 2015, 'Improving Geotechnical Properties of Closed Landfills for Redevelopment Using Chemical Stabilization Techniques' in Indraratna, B, Chu, J & Rujikiatkamjorn, C (eds), Ground Improvement Case Histories, Elsevier, Oxford, pp. 239-266.
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© 2015 Elsevier Ltd. All rights reserved. Construction on closed landfill sites is generally a challenging task due to the complex behavior of creep, settlement, high amount of moisture content, and weak shear strength of waste materials. This chapter presents the experimental results and numerical analyses for the use of fly ash and quicklime in improvement of the geotechnical properties of municipal solid wastes (MSW). The waste materials were collected from a closed landfill in the southwest of Sydney. The samples were prepared by integrating MSW with a mixture of fly ash-quicklime with a ratio of 3:1 in percentages of 5, 10, 15, and 20 of fly ash by dry weight of the MSW. A series of experimental tests and numerical analysis were conducted on treated and untreated MSW samples. It was found that the chemical stabilization effectively increased the compressive strength, the shear strength parameters, the stiffness, and the brittleness index, whereas it decreased the settlement and the permeability of the MSW layer. The finite element program, PLAXIS version 9, was used to evaluate the settlement of a landfill model. The laboratory results were used to validate the numerical model. The settlement of the landfill model 10 and 20 years after the surcharge load was applied for different fly ash-quicklime contents and various depths of improvement was estimated. Results indicated that treatment of MSW significantly reduced the vertical displacement of the landfill model under surcharge load. This reduction was greater with higher depths of improvement.

Fatahi, B, Pathirage, U, Indraratna, B, Pallewattha, M & Khabbaz, H 2015, 'The Role of Native Vegetation in Stabilizing Formation Soil for Transport Corridors' in Indraratna, B, Chu, J & RUJIKIATKAMJORN, C (eds), Ground Improvement Case Histories, Elsevier, Oxford, pp. 591-628.
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© 2015 Elsevier Ltd. All rights reserved. This chapter describes a detailed field investigation conducted near an Australian native tree, Eucalyptus largiflorens. This investigation included field procedures such as drilling boreholes and taking soil samples, measuring the soil moisture content, soil suction, and also excavating trenches to observe the distribution of tree roots under the ground. It also includes the development a root water uptake model to examine and explain the soil properties, specifications for vegetation, and meteorological conditions; this root water uptake model incorporates key factors such as soil suction, active root density distribution, and potential transpiration. A two-dimensional finite element approach based on ABAQUS software was used to solve the transient coupled flow and deformation equations. The root water uptake model was implemented into the coupled analysis by introducing a sink term as a subroutine in the finite element analysis. The finite element mesh can be constructed using partially/fully saturated soil elements to represent the salient aspects of unsaturated permeability and the soil water characteristic curve. The model was formulated on the general effective stress theory of unsaturated soils, and based on this proposed model, the matric suction profile adjacent to the tree was analyzed numerically. To verify the model, the soil moisture content and suction profiles measured on site were compared to the predicted values, and profiles of ground settlement and lateral movement adjacent to the tree are presented and interpreted. By considering the various properties of the soil, types of vegetation, and atmospheric conditions, the proposed model would be of most use in predicting how this formation would react in a rail environment because the model developed in this study may improve the design and construction procedures for railway lines, foundations, and embankments near native vegetation. However, be...

Aslani, F, Nejadi, S & Samali, B 2015, 'Instantaneous and time-dependent flexural cracking models of reinforced self-compacting concrete slabs with and without fibres', COMPUTERS AND CONCRETE, vol. 16, no. 2, pp. 223-243.
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© 2015 Techno-Press, Ltd. Self-compacting concrete (SCC) can be placed and compacted under its own weight with little or no compaction. It is cohesive enough to be handled without segregation or bleeding. Modifications in the mix design of SCC may significantly influence the material's mechanical properties. Therefore, it is vital to investigate whether all the assumed hypotheses about conventional concrete (CC) are also valid for SCC structures. The aim in this paper is to develop analytical models for flexural cracking that describe in appropriate detail the observed cracking behaviour of the reinforced concrete flexural one way slabs tested. The crack width and crack spacing calculation procedures outlined in five international codes, namely Eurocode 2 (1991), CEB-FIP (1990), ACI318-99 (1999), Eurocode 2 (2004), and fib-Model Code (2010), are presented and crack widths and crack spacing are accordingly calculated. Then, the results are compared with the proposed analytical models and the measured experimental values, and discussed in detail.

Azari, B, Fatahi, B & Khabbaz, H 2015, 'Numerical analysis of vertical drains accelerated consolidation considering combined soil disturbance and visco-plastic behaviour', GEOMECHANICS AND ENGINEERING, vol. 8, no. 2, pp. 187-220.
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© 2015 Techno-Press, Ltd. Soil disturbance induced by installation of mandrel driven vertical drains decreases the in situ horizontal hydraulic conductivity of the soil in the vicinity of the drains, decelerating the consolidation rate. According to available literature, several different profiles for the hydraulic conductivity variation with the radial distance from the vertical drain, influencing the excess pore water pressure dissipation rate, have been identified. In addition, it is well known that the visco-plastic properties of the soil also influence the excess pore water pressure dissipation rate and consequently the settlement rate. In this study, a numerical solution adopting an elastic visco-plastic model with nonlinear creep function incorporated in the consolidation equations has been developed to investigate the effects of disturbed zone properties on the time dependent behaviour of soft soil deposits improved with vertical drains and preloading. The employed elastic visco-plastic model is based on the framework of the modified Cam-Clay model capturing soil creep during excess pore water pressure dissipation. Besides, nonlinear variations of creep coefficient with stress and time and permeability variations during the consolidation process are considered. The predicted results have been compared with Väsby test fill measurements. According to the results, different variations of the hydraulic conductivity profile in the disturbed zone result in varying excess pore water pressure dissipation rate and consequently varying the effective vertical stresses in the soil profile. Thus, the creep coefficient and the creep strain limit are notably influenced resulting in significant changes in the predicted settlement rate.

Azzi, M, Duc, H & Ha, QP 2015, 'Toward sustainable energy usage in the power generation and construction sectors—a case study of Australia', Automation in Construction, vol. 59, pp. 122-127.
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Chen, X, Li, JC, Cai, MF, Zou, Y & Zhao, J 2015, 'Experimental Study on Wave Propagation Across a Rock Joint with Rough Surface', Rock Mechanics and Rock Engineering, vol. 48, no. 6, pp. 2225-2234.
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Dragos, J & Wu, C 2015, 'Single-Degree-of-Freedom Approach to Incorporate Axial Load Effects on Pressure Impulse Curves for Steel Columns', Journal of Engineering Mechanics, vol. 141, no. 1, pp. 04014098-04014098.
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© 2014 American Society of Civil Engineers. In this paper, the moment-curvature behavior of a steel column under constant axial loading is implemented into a computationally efficient one-dimensional finite-element approach, utilizing Timoshenko beam theory, to determine the dynamic response of steel columns subjected to blasts. Then, a new single-degree-of-freedom (SDOF) approach is provided for determining pressure impulse curves for steel columns under constant axial loading. This SDOF approach relies on the newly defined concept of the reduced resistance-deflection function to accurately simulate the PΔ effects and the global instability failure mechanism, which are both caused by the axial load. The aforementioned finite-element approach is then used to thoroughly validate the newly proposed SDOF approach for deriving pressure impulse curves. It is shown that, despite the inherent simplicity of the approach, the newly proposed SDOF approach provides accurate and reliable results.

Fatahi, B & Khabbaz, H 2015, 'Influence of Chemical Stabilisation on Permeability of Municipal Solid Wastes', Geotechnical and Geological Engineering, vol. 33, no. 3, pp. 455-466.
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© 2014, Springer International Publishing Switzerland. There are a number of important challenges in redevelopment of closed landfill sites including high permeation, complexity in settlement behaviour, weak shear strength, gas emission as well as health and safety issues. This paper is a part of a thorough experimental study on chemically stabilised old landfill sites. The decomposed waste materials were collected from Bankstown landfill located in the south-west of Sydney. The samples were prepared by mixing MSW, with a mixture of fly ash–quicklime with a ratio of 3:1 in percentages of 5, 10, 15 and 20 of fly ash by dry weight of the MSW. Permeability of treated and untreated MSW samples has been estimated during consolidation of MSW specimens in an automated triaxial cell. According to the results, increasing the content of fly ash–quicklime in the MSW specimen reduced the coefficient of permeability, the coefficient of consolidation and the permeability change index (Ck). The coefficient of permeability for an untreated specimen was 6.2 × 10−8 m/s and this figure was reduced to 3.2 × 10−8 m/s in specimens mixed with 26 % fly ash–quicklime (under an average confining pressure of 250 kPa). Increasing the effective confining pressure up to the pre-consolidation pressure caused no significant change in the coefficient of permeability. However at higher pressures the reduction was tangible. It is found that the chemical stabilisation effectively reduces the permeability of the MSW layer. This reduction in the coefficient of permeability can be attributed to a reduction in the bleed channels and void spaces due to the conversion of soluble calcium hydroxide to cementitious compounds. It will be beneficial and effective in redevelopment of closed landfill sites incorporating chemical treatments. The outcomes of this study may facilitate the hydraulic properties of chemically treated closed landfill sites.

Ha, Q, Royel, S, Li, J & Li, Y 2015, 'Hysteresis Modeling of Smart Structure MR Devices using Describing Functions', IEEE/ASME Transactions on Mechatronics, vol. 21, no. 1, pp. 1-1.
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© 1996-2012 IEEE. Magnetorheological (MR) devices have been quite promising for semiactive control, thanks to their capability of adjusting structural parameters, under a low-power control signal, to effectively withstand severe dynamic loadings including seismic events. MR devices, using visco-elastic and ferromagnetic materials, are subject to hysteresis, which may degrade the performance of smart structures. Therefore, this multivalued nonlinearity needs to be properly modeled and characterized for control and health monitoring. As engineering structures operate as low-pass filter in normal conditions, it is suitable to use the classical describing function (DF) method for modeling and analysis of the hysteretic behaviors in MR device-based smart structures. Data obtained from characterizing tests are recorded in look-up tables to obtain the DFs for these devices, using a curve-fitting technique. The proposed DFs are then useful in structural frequency analysis. Experimental results are reported for a steel beam with MR pin joints subject to quake-induced vibrations provided by a shake table.

Ha, QP & Vakiloroaya, V 2015, 'Modeling and optimal control of an energy-efficient hybrid solar air conditioning system', AUTOMATION IN CONSTRUCTION, vol. 49, no. Part B, pp. 262-270.
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© 2014 Elsevier B.V. All rights reserved. The paper addresses the modeling and optimal control problem of a new hybrid solar-assisted air conditioning system developed for performance enhancement and energy efficiency improvement. To regulate the mass flow rate of the refrigerant vapor passing through a water storage tank for increasing the refrigerant's sub-cooling process at partial loads, we propose a new discharge bypass line together with an inline solenoid valve, installed after the compressor. In addition, to control the air flow rate, a variable speed drive is coupled with the condenser fan. For the control purpose, a lumped parameter model is first developed to describe the system dynamics in an explicit input-output relationship; then, a linear optimal control scheme is applied for the system's multivariable control. The system has been fully-instrumented to examine its performance under different operation conditions. The system model is then validated by extensive experimental tests. Based on the obtained dynamic model, an optimal controller is designed to minimize a quadratic cost function. Numerical algorithms, implemented in a simulation tool, are then employed to predict the energy performance of the system under transient loads. The experimental results obtained from implementation with PLC demonstrate that the newly-developed system can deliver higher system efficiency owing to amelioration of the refrigeration effect in the direct expansion evaporator and adjustment of its air flow rate. The development is thus promising for improvement of energy efficiency, enhancement of the system performance while fulfilling the cooling demand.

Harte, AM & Crews, K 2015, 'Special issue: Reinforcement of timber structures', Construction and Building Materials, vol. 97, pp. 1-1.
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Ho, L & Fatahi, B 2015, 'Analytical solution for the two-dimensional plane strain consolidation of an unsaturated soil stratum subjected to time-dependent loading', COMPUTERS AND GEOTECHNICS, vol. 67, pp. 1-16.
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© 2015. This paper introduces an exact analytical solution predicting variations in excess pore-air and pore-water pressures and settlement considering the two-dimensional (2D) plane strain consolidation of an unsaturated soil stratum subjected to different time-dependent loadings. Based on the proposed solution, the distributions of excess pore pressures along vertical and horizontal directions can be determined. The general solution is first expressed in a series of eigenfunctions of homogeneous partial differential equations (PDEs) and is then substituted into the governing flow equations. Using term-by-term differentiation and the orthogonality of the sine function, the governing equations become ordinary differential equations (ODEs). Once the complex domain is obtained by applying the Laplace transformation technique, the closed-form analytical solutions describing the dissipation of excess pore-air and pore-water pressures can be obtained by taking a Laplace inverse. In this study, four external loadings, including ramping, asymptotic, sinusoid and damped sine wave, are simulated and incorporated into the proposed solutions. For the data analysis, the 2D consolidation behavior is investigated against variations in the permeability ratio (ka/kw). Additionally, parametric studies regarding loading functions are presented in this paper.

Ho, L, Fatahi, B & Khabbaz, H 2015, 'A closed form analytical solution for two-dimensional plane strain consolidation of unsaturated soil stratum', INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, vol. 39, no. 15, pp. 1665-1692.
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© 2015 John Wiley & Sons, Ltd. This paper discusses the excess pore-air and pore-water pressure dissipations and the average degree of consolidation in the 2D plane strain consolidation of an unsaturated soil stratum using eigenfunction expansion and Laplace transformation techniques. In this study, the application of a constant external loading on a soil surface is assumed to immediately generate uniformly or linearly distributed initial excess pore pressures. The general solutions consisting of eigenfunctions and eigenvalues are first proposed. The Laplace transform is then applied to convert the time variable t in partial differential equations into the Laplace complex argument s. Once the domain is obtained, a simplified set of equations with variable s can be achieved. The final analytical solutions can be computed by taking a Laplace inverse. The proposed equations predict the two-dimensional consolidation behaviour of an unsaturated soil stratum capturing the uniformly and linearly distributed initial excess pore pressures. This study investigates the effects of isotropic and anisotropic permeability conditions on variations of excess pore pressures and the average degree of consolidation. Additionally, isochrones of excess pore pressures along vertical and horizontal directions are presented. It is found that the initial distribution of pore pressures, varying with depth, results in considerable effects on the pore-water pressure dissipation rate whilst it has insignificant effects on the excess pore-air pressure dissipation rate.

Hokmabadi, AS, Fatahi, B & Samali, B 2015, 'Physical Modeling of Seismic Soil-Pile-Structure Interaction for Buildings on Soft Soils', International Journal of Geomechanics, vol. 15, no. 2, pp. 04014046-04014046.
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© 2014 American Society of Civil Engineers. The present research intends to study the effects of the seismic soil-pile-structure interaction (SSPSI) on the dynamic response of buildings with various heights by conducting a series of shaking table tests on 5-, 10-story, and 15-story model structures. Two types of foundations for each case are investigated, including (1) a fixed-base structure, representing the situation excluding the soil-structure interaction; and (2) a structure supported by an end-bearing pile foundation in soft soil. An advanced laminar soil container has been designed that uses three-dimensional numerical modeling to minimize the boundary effects and to simulate free-field motion during the shaking table tests. Four real earthquake events, including Kobe 1995, Northridge 1994, El Centro 1940, and Hachinohe 1968, are imposed to each model. According to the experimental measurements, it is observed that the SSPSI amplifies the maximum lateral deflections and in turn interstory drifts of the structures supported by end-bearing pile foundations in comparison with the fixed-base structures. The rocking component plays an important role in increasing the lateral deflection of the superstructures, which can shift the performance level of the structures to near collapse or even collapse levels and as a result should be assessed precisely in the seismic design of buildings resting on soft soils.

Indraratna, B, Biabani, MM & Nimbalkar, S 2015, 'Behavior of Geocell-Reinforced Subballast Subjected to Cyclic Loading in Plane-Strain Condition', Journal of Geotechnical and Geoenvironmental Engineering, vol. 141, no. 1, pp. 04014081-04014081.
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Indraratna, B, Mahdi Biabani, M & Nimbalkar, S 2015, 'Closure to “Behavior of Geocell-Reinforced Subballast Subjected to Cyclic Loading in Plane-Strain Condition” by Buddhima Indraratna, M. Mahdi Biabani, and Sanjay Nimbalkar', Journal of Geotechnical and Geoenvironmental Engineering, vol. 141, no. 10, pp. 07015028-07015028.
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Indraratna, B, Sun, QD & Nimbalkar, S 2015, 'Observed and predicted behaviour of rail ballast under monotonic loading capturing particle breakage', Canadian Geotechnical Journal, vol. 52, no. 1, pp. 73-86.
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A substantial amount of experimental evidence suggests that the critical state envelope for ballast is nonlinear, especially at low confining pressure. To study the implications of this nonlinearity and the associated role of particle breakage, monotonically loaded drained triaxial tests were conducted using a large-scale cylindrical triaxial apparatus. A nonlinear critical state envelope is determined in the q–p′ and υ–lnp′ planes. Mathematical expressions for critical state stress ratio and specific volume are proposed to incorporate the evolution of particle breakage during monotonic shearing. In this paper, an elastoplastic constitutive model based on the critical state soil mechanics framework is presented to capture the salient aspects of stress–strain behaviour and degradation of ballast. Constitutive parameters were conveniently determined from large-scale laboratory tests. The model is able to predict the monotonic shear behaviour of ballast corroborating with the laboratory measurements. The proposed model is further validated using experimental results available from past independent studies.

Jiang, X, Wang, J, Li, Y, Li, J & Yao, J 2015, 'Energy harvesting for powering wireless sensor networks in low-frequency and large-force environments', Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, vol. 229, no. 11, pp. 1953-1964.
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Over the past few decades, wireless sensor networks have been widely used in the field of structure health monitoring of civil, mechanical, and aerospace systems. Currently, most wireless sensor networks are battery powered and it is costly and unsustainable for maintenance because of the requirement for frequent battery replacements. As an attempt to address such issue, this paper theoretically and experimentally studies a compression-based piezoelectric energy harvester, which is suitable for the low-frequency and large-force working environments, such as in civil and transportation infrastructure applications. The proposed energy harvester employs the piezoelectric structure constructed in multilayer stack configuration to convert ambient vibrations into electrical energy. Based on the linear theory of piezoelectricity, the two-degree-of-freedom electromechanical models of the proposed energy harvester were developed to characterize its performance in generating electrical energy under external excitations. Exact closed-form expressions of the electromechanical models have been derived to analyze the maximum harvested power and the optimal resistance. The theoretical analyses were validated through several experiments for a test prototype under harmonic excitations. The test results exhibit very good agreement with the analytical analyses and numerical simulations for a range of resistive loads and input excitation levels.

Khezri, N, Mohamad, H, HajiHassani, M & Fatahi, B 2015, 'The stability of shallow circular tunnels in soil considering variations in cohesion with depth', Tunnelling and Underground Space Technology, vol. 49, pp. 230-240.
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Khorsandnia, N & Crews, K 2015, 'Application of quasi-brittle material model for analysis of timber members', Australian Journal of Structural Engineering, vol. 16, no. 2, pp. 99-115.
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Khorsandnia, N & Crews, K 2015, 'Application of Quasi-Brittle Material Model for Analysis of Timber Members', Australian Journal of Structural Engineering, vol. 16, no. 2, pp. 99-115.
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Khorsandnia, N, Schänzlin, J, Valipour, H & Crews, K 2015, 'Coupled finite element-finite difference formulation for long-term analysis of timber–concrete composite structures', Engineering Structures, vol. 96, pp. 139-152.
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Krause, M, Dackermann, U & Li, J 2015, 'Elastic wave modes for the assessment of structural timber: ultrasonic echo for building elements and guided waves for pole and pile structures', Journal of Civil Structural Health Monitoring, vol. 5, no. 2, pp. 221-249.
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© 2014, Springer-Verlag Berlin Heidelberg. This paper presents the state-of-the-art of using non-destructive testing (NDT) methods based on elastic waves for the condition assessment of structural timber. Two very promising approaches based on the propagation and reflections of elastic waves are described. While the first approach uses ultrasonic echoes for the testing of wooden building elements, the second approach uses guided waves (GW) for the testing of timber pole and pile structures. The basic principle behind both approaches is that elastic waves induced in a timber structure will propagate through its material until they encounter a change in stiffness, cross-sectional area or density, at which point they will reflect back. By measuring the wave echoes, it is possible to determine geometric properties of the tested structures such as the back wall of timber elements or the underground length of timber poles or piles. In addition, the internal state of the tested structures can be assessed since damage and defects such as rot, fungi or termite attacks will cause early reflections of the elastic waves as well as it can result in changes in wave velocity, wave attenuation and wave mode conversion. In the paper, the principles and theory of using elastic wave propagation for the assessment of wooden building elements and timber pole/pile structures are described. The state-of-the-art in testing equipment and procedures is presented and detailed examples are given on the practical application of both testing approaches. Recent encouraging developments of cutting edge research are presented along with challenges for future research.

Kwok, N, Shi, H, Fang, G, Ha, Q, Yu, Y-H, Wu, T, Li, H & Nguyen, T 2015, 'Color image enhancement using correlated intensity and saturation adjustments', JOURNAL OF MODERN OPTICS, vol. 62, no. 13, pp. 1037-1047.
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© 2015 Taylor & Francis. The enhancement of digital color images needs to be performed in accordance with human perception in terms of hue, saturation, and intensity attributes instead of improving only the contrast. Two approaches were developed in this work, which use a correlated adjustment mechanism incorporating intensity and saturation attributes and provide contrast and saturation enhancements together with brightness consistency. In these algorithms, object edges are emphasized for contrast, and image saturation is increased by boosting the salient regions. Furthermore, intensity and saturation enhancements are carried out in a lattice structure where adjustments are made inter-related for better performance. Experiments were conducted with benchmark and real-world images. Results had shown improvements in image qualities both qualitatively and quantitatively.

Le, TM, Fatahi, B & Khabbaz, H 2015, 'Numerical optimisation to obtain elastic viscoplastic model parameters for soft clay', INTERNATIONAL JOURNAL OF PLASTICITY, vol. 65, pp. 1-21.
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© 2014 Published by Elsevier Ltd. All rights reserved. In this paper, a numerical optimisation procedure is presented to obtain non-linear elastic viscoplastic (EVP) model parameters adopting the available consolidation data. The Crank-Nicolson finite difference scheme is applied to solve the combination of coupled partial differential equations of the EVP model and the consolidation theory. Then, the model parameters are determined applying the trust-region reflective optimisation algorithm in conjunction with the finite difference solution. The proposed solution for the model parameter determination can utilise all available consolidation data during the dissipation of the excess pore water pressure to determine the required model parameters. Moreover, in order to include creep in the numerical predictions explicitly from the very first time steps, the reference time in the elastic viscoplastic model can readily be adopted as a unit of time. Results obtained from two sets of laboratory experiments adopting hydraulic consolidation (Rowe cells) on a soft soil are reported and discussed. The proposed numerical optimisation procedure is utilised to obtain the viscoplastic model parameters adopting the experimental results, while the settlement and pore water pressure predictions are compared with experimental results to evaluate the accuracy and reliability of the proposed numerical procedure. The predictions are in good agreement with the measurements, supporting the proposed numerical method as a practical tool to analyse the stress-strain behaviour of soft clay.

Le, TM, Fatahi, B, Disfani, M & Khabbaz, H 2015, 'Analyzing consolidation data to obtain elastic viscoplastic parameters of clay', GEOMECHANICS AND ENGINEERING, vol. 8, no. 4, pp. 559-594.
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© 2015 Techno-Press, Ltd. A nonlinear creep function incorporated into the elastic visco-plastic model may describe the long-term soil deformation more accurately. However, by applying the conventional procedure, there are challenges to determine the model parameters due to limitation of suitable data points. This paper presents a numerical solution to obtain several parameters simultaneously for a nonlinear elastic visco-plastic (EVP) model using the available consolidation data. The finite difference scheme using the Crank-Nicolson procedure is applied to solve a set of coupled partial differential equations of the time dependent strain and pore water pressure dissipation. The model parameters are determined by applying the algorithm of trust-region reflective optimisation in conjunction with the finite difference solution. The proposed method utilises all available consolidation data during dissipation of the excess pore water pressure to determine the required model parameters. Moreover, the reference time in the elastic visco-plastic model can readily be adopted as a unit of time; denoting creep is included in the numerical predictions explicitly from the very first time steps. In this paper, the settlement predictions of thick soft clay layers are presented and discussed to evaluate and compare the accuracy and reliability of the proposed method against the graphical procedure to obtain the model parameters. In addition, comparison of the available experimental results to the numerical predictions confirms the accuracy of the numerical procedure.

Li, J, Wu, C & Hao, H 2015, 'An experimental and numerical study of reinforced ultra-high performance concrete slabs under blast loads', Materials & Design, vol. 82, pp. 64-76.
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© 2015 Elsevier Ltd. Ultra-high performance concrete (UHPC) which is characterized by high strength, high ductility and high toughness has been widely applied in modern structure construction. Outstanding mechanical feature of UHPC not only enables strong yet slim structure design but also highlights its potential in protective engineering against extreme loads like impact or explosion. In this research a series of reinforced concrete slabs are tested to determine their response under explosive loading conditions. Concrete materials used in the slab construction are ultra-high strength concrete (UHPC) and normal strength concrete (NSC). In total five slabs are tested including four UHPC slabs with varying reinforcement ratios and one control NSC slab with normal reinforcement. Explosive charges with TNT equivalent weights ranging from 1.0 to 14.0 kg at scaled distances ranging from 0.41 to 3.05m/kg^1/3 are used in the current experiments. Test results verified the effectiveness of UHPC slabs against blast loads. Numerical models are established in LS-DYNA to reproduce the field blast tests on UHPC slabs. The numerical results are compared with the field test data, and the feasibility and validity of the numerical predictions of UHPC slab responses are demonstrated.

Li, J, Wu, C & Hao, H 2015, 'Investigation of ultra-high performance concrete slab and normal strength concrete slab under contact explosion', Engineering Structures, vol. 102, pp. 395-408.
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© 2015 Elsevier Ltd. Dynamic performance of concrete structures under blast loading conditions is a topic of importance as such load generates severe structural damage including flexural damage, shear damage and concrete spall damage which may impose threats to the personnel and instruments shielded by the reinforced concrete structure. To mitigate blast effects on civil structures, a new kind of concrete material named Ultra-High-Performance-Concrete (UHPC) is now widely studied and applied. UHPC material is known for its high compressive and tensile strength, large energy absorption capacity as well as good workability and anti-abrasion ability. In a previous study, the performance of UHPC slab under blast loads had been investigated through free air explosion tests. The blast resistance capacity of UHPC had been demonstrated through comparison with normal strength concrete. In the present study, the dynamic performance of UHPC slab under contact charge explosion is experimentally studied and compared with normal strength concrete slab under the same loading scenario. Numerical models are established to reproduce both the previous free air explosion tests and the current contact explosion tests. In particular, finite element model is established to simulate the free air explosion test, and coupled smoothed particle hydrodynamics (SPH) method and finite element method is utilized to simulate the contact blast tests. Numerical results are compared with the experimental observations, and the feasibility and accuracy of the numerical model are validated.

Li, J, Wu, C, Hao, H & Su, Y 2015, 'Investigation of Ultra-High Performance Concrete under Static and Blast Loads', International Journal of Protective Structures, vol. 6, no. 2, pp. 217-235.
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Conventional concrete works as an important construction material. However, conventional concrete is known to be brittle and prone to tensile failure and cracks. To overcome such defects and improve the dynamic performance of concrete against extreme loading conditions, concrete with different additions and formulae have been developed. In a recent study, to develop ultra-high performance concrete (UHPC) material with better strength and crack control ability, super fine aggregates with high pozzolanic effect were mixed into the steel fibre reinforced concrete instead of the traditional graded coarse aggregates. Furthermore, to achieve high early age strength, nanoscale additives which can accelerate the hydration process of the ordinary Portland cement were also introduced into the concrete composite. A series of uniaxial compression and four-point bending tests had been performed in the laboratory to get the material properties of this innovative concrete material. Great improvement of the concrete uniaxial compressive strength and flexural tensile strength was observed. Field blast tests were carried out on columns made of this UHPC material. Superior blast resistance performance was observed. In the current study, based on the available test data, numerical models are developed and numerical simulations are carried out. The simulation results are found to comply well with the experimental results.

Li, JC, Liu, TT, Li, HB, Liu, YQ, Liu, B & Xia, X 2015, 'Shear Wave Propagation Across Filled Joints with the Effect of Interfacial Shear Strength', Rock Mechanics and Rock Engineering, vol. 48, no. 4, pp. 1547-1557.
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Li, W, Huang, Z, Cao, F, Sun, Z & Shah, SP 2015, 'Effects of nano-silica and nano-limestone on flowability and mechanical properties of ultra-high-performance concrete matrix', Construction and Building Materials, vol. 95, pp. 366-374.
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© 2015 Elsevier Ltd. The effects of nano-silica/SiO2 (NS) and nano-limestone/CaCO3 (NC) on the flowability, strengths and microstructure of ultra-high-performance concrete (UHPC) matrix under different curing conditions were investigated in this study. The NS and NC were incorporated at different ratios as partial mass replacements for cement. On the microstructure aspect, the results verify that the NS acts as an effective filling material, which reduced porous areas and accelerated the cement hydration process by pozzolanic effect. On the other hand, the NC acts mainly as an inert filler material that created a denser microstructure, but accelerated the cement hydration process through boundary nucleation growth effect. On the mechanical properties aspect, a threshold value of the NS and NC contents were found so that the compressive, flexural strengths and flexural to compressive strength ratio of the UHPC matrix were found to increase as the NS and NC contents increased towards the threshold content, and then to decrease with the increase of NS and NC contents when the threshold was surpassed. Corresponding to the highest measured mechanical strengths of UHPC matrix, the optimal contents of NS and NC are around 1.0% and 3.0%, respectively. The research concluded that the NS and NC contents are critical to the performance of UHPC matrix.

Li, W, Xiao, J, Kawashima, S, Shekhawat, GS & Shah, SP 2015, 'Experimental Investigation on Quantitative Nanomechanical Properties of Cement Paste', ACI Materials Journal, vol. 112, no. 2, pp. 229-238.
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Copyright © 2015, American Concrete Institute. All rights reserved. Nanoindentation, quantitative modulus mapping, and PeakForce quantitative nanomechanical mapping (QNM) are applied to investigate the quantitative nanomechanics of hardened cement paste at different spatial resolutions. The elastic modulus measured by static nanoindentation is slightly higher than those measured by the other methods. The average elastic modulus and probability obtained by PeakForce QNM are typically consistent with those found by modulus mapping. Both modulus mapping and PeakForce QNM can be used to discriminate different material phases in cement paste at the nanoscale. It concludes that cement paste is a granular material in which the sub-micron scale grains or basic nanoscale units pack together. Moreover, the high resolution Peak-Force QNM can provide an efficient tool for identifying nanomechanical properties, particle sizes, and thickness of the interface between different nanoscale grains.

Li, W, Xiao, J, Shi, C & Poon, CS 2015, 'Structural Behaviour of Composite Members with Recycled Aggregate Concrete — An Overview', Advances in Structural Engineering, vol. 18, no. 6, pp. 919-938.
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A series of investigations on structural behaviour, durability, fire-resistance and seismic performance of composite members with recycled aggregate concrete (RAC) have been carried out in the past 10 years (2005–2014). This paper is consisted of three parts: the first part introduces and discusses the research progress in regard to the structural behaviour of RAC filled steel tubular columns and beams; the second part concentrates on the structural behaviour of steel-reinforced RAC members, including columns, beams, shear walls and slabs; and the third part focuses on the long-term performance of composite members with RAC, involving fire resistance, durability and seismic performance. It seems that RAC composite members with different replacement ratios of recycled coarse aggregate have slightly lower or similar structural behaviour compared to that of normal concrete composite members. Review results reveal that it is feasible to apply steel-RAC composite members as structural applications. This intensive review provides a reasonable knowledge of the structural behaviour of steel-RAC composite members, and recommends further investigations on the failure mechanics and durability of steel-RAC composite members which are needed to promote safe and economic application in the future.

Li, Y & Li, J 2015, 'A Highly Adjustable Base Isolator Utilizing Magnetorheological Elastomer: Experimental Testing and Modeling', JOURNAL OF VIBRATION AND ACOUSTICS-TRANSACTIONS OF THE ASME, vol. 137, no. 1.
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Copyright © 2015 by ASME. This paper presents a recent research advance on the development of a novel adaptive seismic isolation system to be used in seismic protection of civil structures. A highly adjustable laminated magnetorheological elastomer (MRE) base isolator was developed and experimental results show that the prototypical MRE base isolator provides increase in lateral stiffness up to 1630%. To facilitate the structural control development using such adaptive MRE base isolator, an analytical model was developed to simulate its behaviors. Comparison between the analytical model and experimental data proves the effectiveness of such model in reproducing the behavior of MRE base isolator.

Li, Y & Li, J 2015, 'Finite element design and analysis of adaptive base isolator utilizing laminated multiple magnetorheological elastomer layers', Journal of Intelligent Material Systems and Structures, vol. 26, no. 14, pp. 1861-1870.
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Available magnetorheological elastomer devices normally consist one to two layers of small-size magnetorheological elastomer materials. To be used in large-scale structures, magnetorheological elastomer devices with multiple larger magnetorheological elastomer materials are expected. This article addresses the critical issue in designing a large-scale device with multiple layers of low magnetic conductive magnetorheological elastomer materials, that is, magnetic circuit design. The primary target in magnetic circuit design for magnetorheological elastomer devices is to provide sufficient and uniform magnetic field to all magnetorheological elastomer layers in the device. In this article, finite element investigations are conducted. An innovative magnetic circuit design is proposed for magnetorheological elastomer base isolator with multi-layer of magnetorheological elastomer materials. In the design, laminated magnetorheological elastomer and steel structure is adopted as part of the magnetic core together with two steel blocks. Cylindrical steel tube is used as the yoke of the magnetic circuit. Two plates are placed on the top and bottom of the device to form enclosed magnetic path in the device. Finite element results showed that such innovative magnetic design is able to provide sufficient and uniform magnetic field to all magnetorheological elastomer layers, that is, 25 magnetorheological elastomer layers with thickness of 1 mm and diameter of 120 mm in this case. Finally, the influence of lateral deformation of the magnetorheological elastomer base isolator on the magnetic field is investigated. It is found that the magnetic field in magnetorheological elastomer materials deteriorates when the deformation of the device increases.

Liu, H & Madanat, S 2015, 'Adaptive optimisation methods in system-level bridge management', Structure and Infrastructure Engineering, vol. 11, no. 7, pp. 884-896.
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We introduce an approach for modelling the structural deterioration of components of bridges for maintenance optimization purposes. The Markov chain model is found in the maintenance and repair problems since the early 60's, is introduced to the maintenance of road infrastructure in the 1980's, and is made to drive the current bridge maintenance optimization systems. While this model results into solvable programming problems and provides a solution, there are a number of criticisms associated with it. We highlight the shortfalls of the Markov model for bridge lifetime assessment and promote the use of stochastic processes.

Liu, Z, Liang, J & Wu, C 2015, 'Dynamic Green׳s function for a three-dimensional concentrated load in the interior of a poroelastic layered half-space using a modified stiffness matrix method', Engineering Analysis with Boundary Elements, vol. 60, pp. 51-66.
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Loads, B, Li, J, Wu, C & Hao, G 2015, 'Residual Loading Capacity of Ultra-High Performance Concrete Columns After', International Journal of Protective Structures, vol. 6, no. 4, pp. 649-669.
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Columns are essential load carrying structural components and may experience accidental loads such as terrorist bombing attacks during their service life. Damages to columns may trigger structural collapse and it is therefore very important to protect critical load-carrying columns. In recent studies, a novel ultra-high performance concrete (UHPC) material was developed and static loading test results revealed its outstanding mechanical strengths and ductility. The present study investigates the blast load-carrying capacities of columns made of UHPC. Concrete columns built with UHPC were blast tested in the field first; then brought back to laboratory and subjected to static load tests to determine their residual load-carrying capacities after experiencing varying levels of blast damage. The results from the field blast tests and laboratory static load tests for residual load-carrying capacities are presented and discussed in this paper. Numerical models for simulating responses and residual strengths of the UHPC columns after blast loadings are also developed in commercial hydro-code LS-DYNA and presented in the paper. Comparisons between the test data and numerical results are made and the accuracy of the numerical model is validated.

Ma, J, Fan, F, Wu, C & Zhi, X 2015, 'Counter-intuitive collapse of single-layer reticulated domes subject to interior blast loading', Thin-Walled Structures, vol. 96, pp. 130-138.
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Makki Alamdari, M, Li, J & Samali, B 2015, 'Damage identification using 2-D discrete wavelet transform on extended operational mode shapes', Archives of Civil and Mechanical Engineering, vol. 15, no. 3, pp. 698-710.
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Makki Alamdari, M, Samali, B & Li, J 2015, 'Damage localization based on symbolic time series analysis', Structural Control and Health Monitoring, vol. 22, no. 2, pp. 374-393.
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The objective of this paper is to localize damage in a single or multiple state at early stages of development on the basis of the principles of symbolic dynamics. Symbolic time series analysis (STSA) of noise-contaminated responses is used for feature extraction to detect and localize a gradually evolving deterioration in the structure according to the changes in the statistical behaviour of symbol sequences. Basically, in STSA, statistical features of the symbol sequence can be used to describe the dynamic status of the system. Symbolic dynamics has some useful characteristics making it highly demanded for implementation in real-time observation application such as SHM. First, it significantly reduces the dimension of information and provides information-rich representation of the underlying data. Second, symbolic dynamics and the set of statistical measures built upon it represent a solid framework to address the main challenges of the analysis of nonstationary time data. Finally, STSA often allows capturing the main features of the underlying system whilst alleviating the effects of harmful noise. The method presented in this paper consists of four primary steps: (i) acquisition of the time series data; (ii) creating the symbol space to produce symbol sequences on the basis of the wavelet transformed version of time series data; (iii) developing the symbol probability vectors to achieve anomaly measures; and (iv) localizing damage on the basis of any sudden variation in anomaly measure of different locations. The method was applied on a flexural beam and a 2-D planar truss bridge subjected to varying Gaussian excitation in presence of 2% white noise to examine the efficiency and limitations of the method. Simulation results under various damage conditions confirmed the efficiency of the proposed approach for localization of gradually evolving deterioration in the structure; however, for the future work, the method needs to be verified by experimental data.

Mirmomeni, M, Heidarpour, A, Zhao, X-L, Hutchinson, CR, Packer, JA & Wu, C 2015, 'Mechanical properties of partially damaged structural steel induced by high strain rate loading at elevated temperatures – An experimental investigation', International Journal of Impact Engineering, vol. 76, pp. 178-188.
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Mohammadi, I & Khabbaz, H 2015, 'Shrinkage performance of Crumb Rubber Concrete (CRC) prepared by water-soaking treatment method for rigid pavements', Cement and Concrete Composites, vol. 62, pp. 106-116.
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© 2015 Elsevier Ltd. All rights reserved. This investigation deals with the shrinkage properties of rubberised concrete pavement. Arrays of concrete samples were prepared with different water-cement ratios and rubber content. The experimental results revealed that the introduction of rubber into concrete mixes results in the control of shrinkage cracks if the optimised content of rubber is selected. Accordingly, the optimised rubber content was determined based on the mix characteristics, mechanical properties and the results of plastic and drying shrinkage tests. The mechanical strength, toughness, bleeding, plastic shrinkage and drying shrinkage tests were conducted in this experimental program. Analysing the results revealed that the most promising performance results were achieved for samples prepared with the rubber contents of 20% and 25% of fine aggregates, and water-cement ratios of 0.45 and 0.40, respectively.

Mustapha, S, Hu, Y, Nguyen, K, Alamdari, MM, Runcie, P, Dackermann, U, Nguyen, VV, Li, J & Ye, L 2015, 'Pattern recognition based on time series analysis using vibration data for structural health monitoring in civil structures', Electronic Journal of Structural Engineering, vol. 14, no. 1, pp. 106-115.
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A statistical pattern recognition technique was developed based on the time series analysis to detect cracking in steel reinforced concrete structures using vibration measurements. The technique has been developed for the Sydney Harbour Bridge. The measurements were collected from single and tri-axial accel-erometers, which were integrated into sensor nodes that were developed at the National ICT Australia. The approach is based on two staged Auto-Regressive (AR) and Auto-Regressive with exogenous inputs (ARX) prediction models. The variation between the residual errors obtained from the intact and damaged states were used to define a Damage Index (DI) capable of identifying physical changed which could be due to structural damage. The effect of the severity of damage on the deviation of the AR-ARX model from its in-tact state was also scrutinised. The results of the field trial and the laboratory testing demonstrated the ability of the approach in identifying the presence of cracking and handling large volumes of data in a very efficient manner.

Neupane, K, Sriravindrarajah, R, Baweja, D & Chalmers, D 2015, 'Effect of curing on the compressive strength development in structural grades of geocement concrete', CONSTRUCTION AND BUILDING MATERIALS, vol. 94, pp. 241-248.
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Nguyen, VV, Dackermann, U, Li, J, Alamdari, MM, Mustapha, S, Runcie, P & Ye, L 2015, 'Damage identification of a concrete arch beam based on frequency response functions and artificial neural networks', Electronic Journal of Structural Engineering, vol. 14, no. 1, pp. 75-84.
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This paper presents a vibration-based structural health monitoring (SHM) technique for the identification of damage in a concrete arch beam replica section of the Sydney Harbour Bridge. The proposed technique uses residual frequency response functions (FRFs) combined with principal component analysis (PCA) to form a damage specific feature (DSF) that is used as an input parameter to artificial neural networks (ANNs). Extensive laboratory testing and numerical modelling are undertaken to validate the method. In the proposed technique, FRFs are obtained by the standard modal testing and damage is identified using ANNs that innovatively map the DSF to the severity of damage (length of damage cut). The results of the experimental and numerical validation show that the proposed technique can successfully quantify damage induced to a concrete arch beam simulating a real life structural component of the Sydney Harbour Bridge.

Noushini, A, Samali, B & Vessalas, K 2015, 'Ductility and Damping Characteristics of PVA-FRC Beam Elements', ADVANCES IN STRUCTURAL ENGINEERING, vol. 18, no. 11, pp. 1763-1787.
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Rijal, R, Samali, B, Shrestha, R & Crews, K 2015, 'Experimental and analytical study on dynamic performance of timber-concrete composite beams', Construction and Building Materials, vol. 75, pp. 46-53.
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Sri Ravindrarajah, R & Baraca, G 2015, 'High strength ultrafine fly Ash Concretes with Silica Fume or Hydrated Lime Addition', International Journal of Constructive Research in Civil Engineering, vol. 1, no. 1, pp. 14-18.
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Production of sustainable concrete mixes for infrastructure construction is targeted by the concrete industry. This is resulted in the use of supplementary cementitious materials, admixtures and recycled materials. The effects of either silica fume or hydrated lime addition (about 10% by weight of the cementitious materials) on the mechanical properties of high strength fly ash concrete are investigated. The investigated properties are compressive strength, tensile strength, modulus of elasticity and drying shrinkage. The results indicated that the silica fume addition caused the compressive strength to improve by 24% and 15%, at the ages of 28 and 56 days, respectively. On the other hand, the hydrated lime addition had reduced the strength by 12% and 20% at the ages of 28 and 56 days, respectively. The modulus of elasticity of concrete was found to increase by the addition both silica fume and hydrated lime. 56-day drying shrinkage was increased by 3% or 14%, by the silica fume or hydrated lime addition, respectively. It is concluded that the addition of 10% hydrated lime to fly ash concrete had the undesirable effects of reducing compressive strength and increasing the drying shrinkage. On the other hand the addition of silica fume resulted in improved hardened concrete properties.

Sun, W-J, Wei, Z-F, Sun, D-A, Liu, S-Q, Fatahi, B & Wang, X-Q 2015, 'Evaluation of the swelling characteristics of bentonite–sand mixtures', Engineering Geology, vol. 199, pp. 1-11.
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© 2015 Elsevier B.V. The swelling characteristic of bentonite-sand mixtures is an important index in evaluating the long term performance of the deep geological repository of nuclear waste. In this study the swelling characteristics of different types of bentonite-sand mixtures with various sand contents are compared. It is concluded that for pure bentonite and bentonite-sand mixtures with less sand than the critical sand content, the relationship between montmorillonite void ratio and vertical stress can be expressed as a unique line in a double logarithmic plot, and volumetric strain under a given vertical stress and swelling pressure at a constant volume after full saturation can be predicted based on this line; however, for mixtures with more sand than the critical sand content, the above relationship deviates from the line when the stress is larger than the starting deviation stress, which can be determined using the sand skeleton void ratio. Before the sand skeleton forms, the vertical stress is borne mainly by montmorillonite particles and the amount of swelling at full saturation is determined by the content of montmorillonite per unit volume, however, after the sand skeleton forms the vertical stress is borne by both the montmorillonite and the sand skeleton. The stress distribution coefficient is proposed to present a proportion of the vertical stress that is borne by both parts. A predictive method, verified by the swelling tests on bentonite-sand mixtures with various sand contents, is suggested to predict the amount of swelling due to saturation in the full range of sand content.

Tabatabaiefar, HR, Fatahi, B, Ghabraie, K & Zhou, W-H 2015, 'Evaluation of numerical procedures to determine seismic response of structures under influence of soil-structure interaction', Structural Engineering and Mechanics, vol. 56, no. 1, pp. 27-47.
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Copyright © 2015 Techno-Press, Ltd. In this study, the accuracy and reliability of fully nonlinear method against equivalent linear method for dynamic analysis of soil-structure interaction is investigated comparing the predicted results of both numerical procedures with the results of experimental shaking table tests. An enhanced numerical soil-structure model has been developed which treats the behaviour of the soil and the structure with equal rigour. The soil-structural model comprises a 15 storey structural model resting on a soft soil inside a laminar soil container. The structural model was analysed under three different conditions: (i) fixed base model performing conventional time history dynamic analysis, (ii) flexible base model (considering full soil-structure interaction) conducting equivalent linear dynamic analysis, and (iii) flexible base model performing fully nonlinear dynamic analysis. The results of the above mentioned three cases in terms of lateral storey deflections and inter-storey drifts are determined and compared with the experimental results of shaking table tests. Comparing the experimental results with the numerical analysis predictions, it is noted that equivalent linear method of dynamic analysis underestimates the inelastic seismic response of mid-rise moment resisting building frames resting on soft soils in comparison to the fully nonlinear dynamic analysis method. Thus, inelastic design procedure, using equivalent linear method, cannot adequately guarantee the structural safety for mid-rise building frames resting on soft soils. However, results obtained from the fully nonlinear method of analysis fit the experimental results reasonably well. Therefore, this method is recommended to be used by practicing engineers.

Tennakoon, N, Indraratna, B, Nimbalkar, S & Sloan, SW 2015, 'Application of bounding surface plasticity concept for clay-fouled ballast under drained loading', Computers and Geotechnics, vol. 70, pp. 96-105.
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Thomas, PS, Heide, K & Földvari, M 2015, 'Water and hydrogen release from perlites and opal', Journal of Thermal Analysis and Calorimetry, vol. 120, no. 1, pp. 95-101.
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© 2014 Akadémiai Kiadó, Budapest, Hungary The dehydration of two specimens of perlite from Pálháza (Hungary) and from Borovitza (Bulgaria) along with a specimen of Australian precious opal has been investigated by temperature controlled high-vacuum degassing experiments (DEGAS). Dehydration results in the loss of water over a wide range of temperatures due to the presence of both molecular and bound (silanol, Si–OH) water. A surprising observation is that hydrogen (H2) is also released. The hydrogen is observed to be released from both perlites and opal and both by diffusional processes and through the sudden explosive, bursting of inclusions which produce sharp spikes in the MS data. The origin of the hydrogen cannot be explained by a simple statistical distribution of the silanol species in the vitreous matrix; rather, it is more likely to be associated with an inverse-micellar decomposition of silanol species. Alternate sources of hydrogen such as meteoric waters or specific genetic origins based on the perlite or opal location and formation are discounted as the hydrogen release is found to be independent of CO2 and SO2 evolution.

Tran, T & Ha, QP 2015, 'Dependable control systems with Internet of Things', ISA Transactions, vol. 59, pp. 303-313.
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Vakhshouri, B & Nejadi, S 2015, 'Predicition Of Compressive Strength In Light-Weight Self-Compacting Concrete By ANFIS Analytical Model', Archives of Civil Engineering, vol. 61, no. 2, pp. 53-72.
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AbstractLight-weight Self-Compacting Concrete (LWSCC) might be the answer to the increasing construction requirements of slenderer and more heavily reinforced structural elements. However there are limited studies to prove its ability in real construction projects. In conjunction with the traditional methods, artificial intelligent based modeling methods have been applied to simulate the non-linear and complex behavior of concrete in the recent years. Twenty one laboratory experimental investigations on the mechanical properties of LWSCC; published in recent 12 years have been analyzed in this study. The collected information is used to investigate the relationship between compressive strength, elasticity modulus and splitting tensile strength in LWSCC. Analytically proposed model in ANFIS is verified by multi factor linear regression analysis. Comparing the estimated results, ANFIS analysis gives more compatible results and is preferred to estimate the properties of LWSCC.

Wu, APC, Hao, H & Li, Z-X 2015, 'A Special Issue on Protection of Structures against Hazards', International Journal of Protective Structures, vol. 6, no. 2, pp. i-i.
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Wu, C & Lok, T-S 2015, 'Special Issue on Blast Effects on Constructed Facilities', Journal of Performance of Constructed Facilities, vol. 29, no. 5.
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Xia, Y, Wu, C & Li, Z-X 2015, 'Optimized Design of Foam Cladding for Protection of Reinforced Concrete Members under Blast Loading', Journal of Structural Engineering, vol. 141, no. 9, pp. 06014010-06014010.
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© 2014 American Society of Civil Engineers. A load-cladding-structure (LCS) model was used to study the mitigating effect provided by metallic foam cladding against blast loading on reinforced concrete (RC) structural members. The model considered the interactions between an external blast load, a protecting foam cladding, and a target RC structural member. The effectiveness of the LCS model was validated by field blast tests conducted in 2009. The validated model was then used to derive pressure impulse diagrams of the foam-protected RC members. Afterwards, two nondimensional parameters representing the relationship between the foam cladding and the target RC member were characterized. Using the suggested nondimensional parameters, normalized pressure-impulse (p-i) diagrams for the foam-protected RC members were generated. The effects of the two nondimensional parameters on the p-i diagrams were investigated by comparing the corresponding asymptotes. Based on the predicted results, an optimized design of the foam cladding for RC structural members was suggested.

Xu, J, Wu, C, Li, Z-X & Ng, C-T 2015, 'Numerical analysis of shear transfer across an initially uncrack reinforced concrete member', Engineering Structures, vol. 102, pp. 296-309.
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© 2015 Elsevier Ltd. An investigation of shear transfer behavior in initially uncracked reinforced concrete members is conducted using finite element modeling method in this study. Although earlier experimental studies have been carried out to identify the role of different design parameters on the ultimate shear strength, there are no design provisions that are available to predict the relationship of shear stress to slip as a function of the basic parameters. One of the aims of this paper is to improve insight into the characteristics between the shear stress and slip for a range of design parameters, such as concrete strength, percentage of dowel and variation of lateral normal pressure on RC members. The other aim of this paper is to derive a set of simplified equations for evaluating the ultimate shear stress and relationship of shear stress to slip in practical structural design. High-fidelity finite element models are developed using LS-DYNA program to simulate push-off tests, and the models are calibrated using experimental results. Parametric studies are then carried out to generate data with the consideration of different combinations of the structural design parameters, i.e., concrete strength, percentage of dowel steel and lateral normal pressures. It is found that the numerical models are accurate in predicting the interface shear strength and slip occurring along the shear plane of the push-off test specimens. The study also shows that there is a good agreement in predicting the shear stress to slip relationship between the results calculated by simplified equations and numerical models, and experimental results.

Yongsheng Zhao, Yifeng Zhang, Rong Xiong & Jianguo Wang 2015, 'Optimal State Estimation of Spinning Ping-Pong Ball Using Continuous Motion Model', IEEE Transactions on Instrumentation and Measurement, vol. 64, no. 8, pp. 2208-2216.
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Zhang, F, Wu, C, Li, Z-X & Zhao, X-L 2015, 'Residual axial capacity of CFDST columns infilled with UHPFRC after close-range blast loading', Thin-Walled Structures, vol. 96, pp. 314-327.
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© 2015 Elsevier Ltd. Concrete-filled double-skin tubes (CFDST) consist of two concentrically placed steel tubes with concrete filled in between and they have more and more commonly been used in the field of civil engineering in recent years. A number of recent researches evidenced the excellent performance of CFDST columns under a variety of loading conditions. However, very limited knowledge is known about the residual axial capacity of CFDST columns following severe blast loadings. This paper presents an experimental study on the residual behaviours of ultra-high performance concrete infilled double-skin steel tubular columns after close-in blast loading. In total, eight CFDST columns, including 3 square ones and 5 circular ones, were first tested under different blast loads with two axial load levels. After the blast tests, all CFDST columns were transported to the laboratory and each of them was then subjected to static axially compressive load until failure. It was found that the CFDST columns with smaller permanent displacement had larger peak residual axial capacity and the CFDST columns which were not subjected to axial load during the blast test exhibited more ductile behaviour than those which were axially loaded during the blast test.

Zhang, F, Wu, C, Wang, H & Zhou, Y 2015, 'Numerical simulation of concrete filled steel tube columns against BLAST loads', Thin-Walled Structures, vol. 92, pp. 82-92.
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Zhang, F, Wu, C, Zhao, X-L, Li, Z-X, Heidarpour, A & Wang, H 2015, 'Numerical Modeling of Concrete-Filled Double-Skin Steel Square Tubular Columns under Blast Loading', Journal of Performance of Constructed Facilities, vol. 29, no. 5.
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Zhang, H, Li, Z & Wu, C 2015, 'Investigation of Blast Effects on Double-Skinned Composite Steel Tubular Columns', International Journal of Protective Structures, vol. 6, no. 3, pp. 403-418.
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In recent years, concrete filled double skin steel tube (CFDST) members have gained interest due to its attractive properties such as ease of construction, light weight, high strength and good seismic resistance, and thus it is expected that these members have the potential of being used in construction of buildings. However, there is lack of understanding about the inelastic behaviors of CFDST members under blast loads. In this paper, based on the ConWep airblast loading model, the blast resistance of typical circular CFDST columns used in engineering field is investigated and the multiple failure modes of CFDST columns under blast loading are analyzed. The influence of explosive charge weights and column axial loading condition on the response of CFDST columns are investigated through parametric study. Finally, the direct shear and flexural failure modes of CFDST columns are analyzed, and uncoupled P-I (pressure-impulse) diagrams are obtained based on an equivalent single degree of freedom (SDOF) system. This study helps to understand the non-linear behaviors of CFDST columns subjected to blast loading.

Zhang, Y, Xiong, R, Zhao, Y & Wang, J 2015, 'Real-Time Spin Estimation of Ping-Pong Ball Using Its Natural Brand', IEEE Transactions on Instrumentation and Measurement, vol. 64, no. 8, pp. 2280-2290.
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Zheng, J, Li, Y, Li, Z & Wang, J 2015, 'Transient multi-physics analysis of a magnetorheological shock absorber with the inverse Jiles–Atherton hysteresis model', Smart Materials and Structures, vol. 24, no. 10, pp. 105024-105024.
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© 2015 IOP Publishing Ltd. This paper presents multi-physics modeling of an MR absorber considering the magnetic hysteresis to capture the nonlinear relationship between the applied current and the generated force under impact loading. The magnetic field, temperature field, and fluid dynamics are represented by the Maxwell equations, conjugate heat transfer equations, and Navier-Stokes equations. These fields are coupled through the apparent viscosity and the magnetic force, both of which in turn depend on the magnetic flux density and the temperature. Based on a parametric study, an inverse Jiles-Atherton hysteresis model is used and implemented for the magnetic field simulation. The temperature rise of the MR fluid in the annular gap caused by core loss (i.e. eddy current loss and hysteresis loss) and fluid motion is computed to investigate the current-force behavior. A group of impulsive tests was performed for the manufactured MR absorber with step exciting currents. The numerical and experimental results showed good agreement, which validates the effectiveness of the proposed multi-physics FEA model.

Zheng, J-J, Wang, X-J, Ouyang, Q, Li, Y-C & Wang, J 2015, 'Modeling and characterization of novel magnetorheological (MR) cell with individual currents', Journal of Central South University, vol. 22, no. 7, pp. 2557-2567.
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© 2015, Central South University Press and Springer-Verlag Berlin Heidelberg. Magnetorheological (MR) cell with multi-coil was designed to enlarge the range of controllable transmission torque by increasing the effective length. Individual input current was proposed to maximize its potential for reducing power consumption and generating large yield stress. Finite element analysis was performed to analyze magnetic field distribution, based on which a prototype MR cell was fabricated and tested to investigate the performance of various combinations of individual input currents. A good correlation was identified between experimental results and FEA predications. The results show that the power consumption can be reduced to 42.4%, maintaining large transmission torque, by distributing the total current (2 A) to three individual magnetic coils. In addition, optimal results of four input currents considering a multi-objective function are obtained by changing the weighting factor λ. The advantage of this design, such as lower power consumption and more control flexibility, makes it more competitive in engineering applications that require large energy consumption.

Alamdari, MM, Khoa, NLD, Runcie, P, Mustapha, S, Dackermann, U, Li, J, Nguyen, VV & Gu, X 1970, 'Application of unsupervised support vector machine for condition assessment of concrete structures', Proceedings of the Second International Conference on Performance-based and Life-cycle Structural Engineering (PLSE 2015), International Conference on Performance-based and Life-cycle Structural Engineering, School of Civil Engineering, The University of Queensland.
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Banihashemi Namini, S, Ding, GK & Wang, J 1970, 'Developing an artificial intelligence-based decision making tool for energy optimization of residential buildings in BIM', The Construction, Building and Real Estate Research Conference of the Royal Institution of Chartered Surveyors, The Australasian Universities' Building Educators Association Conference, Australian Universities Building Education Association Annual Conference, Royal Institution of Chartered Surveyors, Sydney, Australia, pp. 1-8.
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In the recent decade, the potential of saving energy by systematic building management is known to be significant and this task should be considered throughout the lifecycle of a building. However, the most effective decisions related to sustainable design of a building facility are made in the feasibility and early design stages. Using building information modelling can expedite this process and provide the opportunity of testing and assessing different design alternatives and materials selection that may impact on energy performance of buildings. Thus, to proactively rectify building performance issues and improve energy efficiency, there is a need for robust methods that can assist with detection, measurement and optimization of energy performance during the early design stage. The main goal for this paper is to study the possibility of interactions between BIM and energy efficient buildings out of application of cutting-edge technologies such as artificial intelligene methods and develop a framework of this interaction as the downstream to establish a better connection among sustainability and information theories as the upstream. Therefore, through this study, a well-established framework that gives a schematic knowledge of BIM applicability in terms of sustainability and energy optimization through utilizing new computational algorithims will be presented.

Biabani, MM, Indraratna, B & Nimbalkar, S 1970, 'Behaviour of geocell reinforced sub-ballast under cyclic loading', FROM FUNDAMENTALS TO APPLICATIONS IN GEOTECHNICS, 15th Pan-American Conference on Soil Mechanics and Geotechnical Engineering (PCSMGE) / 8th South American Congress on Rock Mechanics (SCRM), IOS PRESS, Buenos Aires, ARGENTINA, pp. 109-119.
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Chua, L, Head, K, Thomas, P & Stuart, B 1970, 'Raman and FTIR analysis of paints applied on ceremonial objects of the Highlands of Papua New Guinea', TECHNART 2015, Catania.

Dang, L, Hasan, H, Fatahi, B & Khabbaz, H 1970, 'Influence of Bagasse Ash and Hydrated Lime on Strength and Mechanical Behaviour of Stabilised Expansive Soil', GEOQuébec 2015, GEOQuébec 2015, Québec City, Canada.

Dang, L., Hasan, H., Fatahi, B., Jones, R. & Khabbaz, H. 1970, 'Effects of Bagasse Ash and Hydrated Lime Addition on Engineering Properties of Expansive Soil', GEOMATE 2015, GEOMATE 2015, The GEOMATE International Society, Osaka, Japan.

Far, H 1970, 'Shaking Table Tests on Soil-Structure System to Determine Lateral Seismic Response of Buildings', The Tenth Pacific Conference on Earthquake Engineering Building an Earthquake, Pacific Conference on Earthquake Engineering, Sydney, Australia.
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In this study, a series of experimental shaking table tests were performed on a physical fixed based model (structure directly fixed on top of the shaking table) and a flexible base model (soil-structure system) under the influence of four scaled earthquake acceleration records (two near field and two far field records) and the results were measured. The soil-structure system includes a 15 storey structural model resting on a synthetic clayey soil mixture consisting of kaolinite, bentonite, class F fly ash, lime, and water. The selected soil model was placed into a laminar soil container, designed and constructed to realistically simulate the free field conditions in shaking table tests. Comparing the measured response of fixed base and flexible base models, it is noted that the lateral deflections of flexible base model have evidently amplified in comparison to the fixed base model. As a result, performance level of the structural model may change extensively (e.g. from life safe to near collapse level), which may be extremely dangerous and safety threatening. Thus, it is experimentally observed that dynamic soil-structure interaction plays a significant role in seismic behaviour of moment resisting building frames resting on relatively soft soils

Far, H, Far, C & Khadivi Zand, MJ 1970, 'Experimental Investigations on Behaviour of Steel Structure Buildings', The Tenth Pacific Conference on Earthquake Engineering Building an Earthquake, Pacific Conference on Earthquake Engineering, Sydney, Australia.
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In this study, a comprehensive procedure for design, building and commissioning of scale steel structure building models has been developed and presented for practical applications in shaking table test programmes. To validate the model, shaking table tests and numerical time history dynamic analyses were performed under the influence of different scaled earthquake acceleration records. Comparing the numerical predictions and experimental values of maximum lateral displacements, it became apparent that the numerical predictions and laboratory measurements are in a good agreement. As a result, the scale structural model can replicate the behaviour of real steel structure buildings with acceptable accuracy. It is concluded that the physical model is a valid and qualified model which can be employed for experimental shaking table tests.

Fatahi, B & Khabbaz, H 1970, 'Research-based computer games to train civil engineering students to be lifelong learners', Proceedings of the 43rd SEFI Annual Conference 2015 - Diversity in Engineering Education: An Opportunity to Face the New Trends of Engineering, SEFI 2015, SEFI - Annual Conference of European Society for Engineering Education, SEFI, Orléans, France, pp. 56389-1-56389-8.
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In spite of vast efforts to adopt available information technology in higher education teaching and learning, the truth is that most of university students and academic staff make only limited use of communication technology. Selwyne [1] concluded that there is a growing need for the education community to account for the distinct ?digital disconnect? between the enthusiastic rhetoric and rather more mundane reality of university information and communication technology use. Recent advances in computer science and multimedia as well as optimistic effects of multifaceted modes of education on student learning, have encouraged teachers to look at adopting the new technology to improve students? learning experience. Chang et al. [2] have suggested that digital games can be powerful informal learning environments encouraging active and critical learning, supplementing traditional teaching methods. It is well accepted that well designed discipline based computer games can help with student learning process and experience in higher education. In this study, a computer game called ?Back to Bedrock? has been developed for soil Behaviour subject at undergraduate level and students? learning process has been monitored and evaluated. It was aimed to help Civil Engineering students with information collection methods, creative thinking, problem solving, and lifelong learning abilities, through a research-based computer game. The results of this project indicate that implementing innovative methods such as computer game based assignments can provide enjoyable competitive and cooperative learning environment enhancing students? learning motivation, and critical thinking abilities, improving the overall performance of students in the subject.

Fatahi, B, Khabbaz, H & Ho, L 1970, 'Debate Activity as an Effective Interactive Learning Approach for Civil Engineering Students', 26th Annual Conference of the Australasian Association for Engineering Education (AAEE 2015), AAEE - Annual Conference of Australasian Association for Engineering Education, Deakin University Press, Geelong, Australia, pp. 980-990.
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The research team has attempted to improve the learning experience of Civil Engineering students by introducing debate activities in engineering subjects. This could encourage the students to be active learners (against passive learner or lecture receivers) and we consider this process as an activity (what students actually do) and not a task (the work prescribed by the teacher). In this project, a main stream civil engineering subject, namely Soil Behaviour has been targeted. Feedback received from the students has indicated that the developed in-class debate activity has been effective in improving communication and critical-thinking skills of students. Availability of new collaborative theatres and collaborative learning spaces could add great advantages to enhancing the efficiency of collaborative group work, in terms of planning and preparation for the debates. In addition, available online discussion boards and online subject website would provide flexibility for students to access digital resources and prepare their arguments. The professional training sessions, on the other hand, could equip participants with important tips to improve the argument presentation skills while were trained to overcome the panic and fear of making mistakes during the speech. International students, whose English is not their first language, were particularly encouraged to attend the training sessions helping them to obtain profound presentation skills not only for Soil Behaviour debate but also for their future career.

Fatahi, B, Khabbaz, H & Valipour, H 1970, 'Application of research-inspired assessment to enhance students learning in civil engineering', Proceedings of the 43rd SEFI Annual Conference 2015 - Diversity in Engineering Education: An Opportunity to Face the New Trends of Engineering, SEFI 2015, SEFI - Annual Conference of European Society for Engineering Education, SEFI, Orléans, France, pp. 56388-1-56388-8.
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The relationship between teaching and research has become a highly challenging issue due to evidence of synergy between them and complexity of integrating them. As reported by Locke [1], the separation of research and teaching could be the result of policy and operational decisions to distinguish the way these activities are funded, managed, assessed and rewarded. However, this would not necessarily excuse higher education institutions from a commitment to optimise the beneficial relations between teaching and research. For example, research conducted by Posch and Steiner [2] at the Swiss Federal Institute of Technology (ETH) in Zurich on innovation for sustainability, concludes that appropriate integration of research and teaching activities leads to mutual benefits for both higher education institutions and students. In this study an approach introducing research activities in Civil Engineering subjects to enable students to develop skills within critical and creative thinking and being lifelong learners has been developed and evaluated. Research based activities/assessments in two major Civil Engineering subjects at undergraduate level have been introduced, and students? learning process has been monitored and evaluated. The results of this project indicate that by incorporating research components in subjects, research-based learning culture among Civil Engineering students were developed. This clearly gave more satisfaction to the students about the learning experience. Statistical analysis of results indicated that students with better performance in mini-projects performed better in the final exam, which was a totally independent assessment task. In addition, the averaged final exam mark of students with good quality projects was higher than the one for other students.

Ghosh, B, Fatahi, B, Kamruzzaman, AHM & Khabbaz, H 1970, 'Assessing load transfer mechanism in CMC-supported embankments adopting Timoshenko beam theory', Geotechnical Engineering for Infrastructure and Development - Proceedings of the XVI European Conference on Soil Mechanics and Geotechnical Engineering, ECSMGE 2015, XVI European Conference on Soil Mechanics and Geotechnical Engineering, Ice Virtual Library, Edinburgh, Scotland, pp. 577-582.
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Controlled modulus columns (CMC) supported embankments are increasingly being used for construction of major highway embankments on expansive soils particularly near waterways or coastal regions. CMC is a faster, sustainable and economical ground improvement technology that stiffens the poor soil and transmits the load from the traffic to a lower bearing stratum. The key influencing elements of the load transfer mechanism include embankment fill, load transfer platform (LTP), CMC and the underlying soils. Use of LTP enhances the load distribution mechanism in the CMC improved soft ground and minimises the post construction settlement of the ground. In this paper, reinforced Timoshenko beam theory is introduced to simulate the LTP with one layer of geosynthetics resting on CMC improved soft soil. A parametric study is conducted to investigate the importance of the height of the embankment on the maximum settlement of the LTP, tension developed in the geosynthetics and stress concentration ratio (the ratio of the stresses acting on CMC and soft soils) for the CMC supported embankments. Special attention is given to the stiffness of soft soil and shear stiffness of the geosynthetic layer. It has been observed that height of the embankment, the stiffness of the soft soil and the shear stiffness of the geosynthetics significantly influence the maximum settlement of the LTP and the stress concentration ratio.

Hassani, M, Baweja, D, Vessalas, K & Schmidt, Z 1970, 'Benefits of Permeability Reducing Admixtures to Watertight Concrete', 27th Biennial National Conference of the Concrete Institute of Australia in conjunction with the 69th RILEM Week, Concrete Institute of Australia, Procs 27th Biennial National Conference of the Concrete Institute of Australia in conjunction with the 69th RILEM Week.

Ho, L, Fatahi, B & Khabbaz 1970, 'Exact analytical solution for one-dimensional consolidation of unsaturated soil stratum subjected to damped sine wave loading', Proceedings of 12th Australia New Zealand Conference on Geomechanics, 12th Australia New Zealand Conference on Geomechanics, Wellington, New Zealand, pp. 1-8.
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A considerable surcharge exerted on an unsaturated soil stratum leads to the emergence of excess pore pressures. During the consolidation process, these pressures tend to dissipate towards permeable boundary surfaces, resulting in a reduction of the soil volume. Such phenomenon can be mathematically described by inhomogeneous governing equations of flow based on Fick’s law (with respect to air phase) and Darcy’s law (with respect to water phase). This paper discusses the dissipation of excess pore-air and pore-water pressures and settlement of an unsaturated soil stratum subjected to an external damped sine wave loading. An analytical solution is derived from the governing equations of flow using eigenfunction expansion and Laplace transformation methods. Eigenfunctions and eigenvalues are parts of the general solution and can be obtained based on oneway drainage boundary condition. On the other hand, the damped sine wave loading is mathematically simulated and incorporated in the solution. Once the time variable (t) in partial differential equations is transformed into the Laplace complex argument (s), generalised Fourier coefficients can be computed by taking a Laplace inverse, and then the final solution can be obtained. In this study, the air to water permeability ratio (k /k ), influencing changes in dissipation rates of excess pore pressures and settlement are investigated and discussed. It is observed that the increasing permeability ratio has a significant effect on the change in the pore pressures.

Hunt, A, Stuart, B, Thomas, P & James, D 1970, 'Characterisation of an unusual purple pigment from a rock art site in western Arnhem Land', Australian Archaeological Association 2015 Conference, Fremantle.

Hunt, A, Stuart, B, Thomas, P, James, D, David, B, Geneste, J-M & Delannoy, J-J 1970, 'The characterisation of Jawoyn rock art paintings in Arnhem Land, Australia using synchrotron infrared microspectroscopy', TECHNART 2015, Catania.

Indraratna, B, Navaratnarajah, S, Nimbalkar, S, Rujikiatkamjorn, C & Neville, T 1970, 'Performance monitoring — case studies of tracks stabilised by geosynthetic grids and prefabricated vertical drains', Proceedings of the Ninth Symposium on Field Measurements in Geomechanics, Ninth International Symposium on Field Measurements in Geomechanics, Australian Centre for Geomechanics, Perth.
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Indraratna, B, Sun, Q & Nimbalkar, S 1970, 'A critical state based constitutive model for the triaxial response of ballast incorporating particle breakage', FROM FUNDAMENTALS TO APPLICATIONS IN GEOTECHNICS, 15th Pan-American Conference on Soil Mechanics and Geotechnical Engineering (PCSMGE) / 8th South American Congress on Rock Mechanics (SCRM), IOS PRESS, Buenos Aires, ARGENTINA, pp. 1232-1239.
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Khamchin Moghaddam, F, Sri Ravindrarajah, R & Sirivivatnanon, V 1970, 'PROPERTIES OF METAKAOLIN CONCRETE – A REVIEW', International Conference on Sustainable Structural Concrete, International Conference on Sustainable Structural Concrete, La Plata, Argentina.
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The use of cement supplementary materials in structural concrete is widely accepted by the construction industry for technical, economical and environmental reasons. Metakaolin (MK), produced by calcining kaolinite at high temperature is suitable for concrete production due to its pozzolanic property. This paper reviews the some of the research published on effects of using MK on engineering properties of structural concrete as a cement replacement material. The review shows that the use of relatively finer MK to partially replace cement reduces the consistency of concrete and enhanced the strengths, deformational and durability properties of concrete. MK is most effective in enhancing compressive strength (particularly at early ages) compared to other strengths and modulus of elasticity was least improved. Drying shrinkage and creep of MK concretes are lower than those for the control concrete. The high pozzolanic reactivity of MK with calcium hydroxide contributes to both porosity reduction and pore-structure refinement in the pastes and concrete. As the consequence, the durability of concrete is improved through increased resistance to chloride penetration and controlled expansion, due to alkali-silica reaction and sodium sulphate attack.

Li, J, Hao, H & Wu, C 1970, 'Preliminary Investigation of Blast Resistance Capacity of Segmented Column Using Numerical Method', Proceedings of the 3rd International Conference on Protective Structures (ICPS3), Newcastle, Australia, 3-6 February 2015, 3rd International Conference on Protective Structures, Centre for Infrastructure Performance and Reliability, University of Newcastle, Newcastle.

Li, J, Wu, C & Hao, H 1970, 'Blast Resistance of Newly Developed Ultra-High Performance Concrete Columns', Proceedings of the 3rd International Conference on Protective Structures (ICPS3), Newcastle, Australia, 3-6 February 2015, 3rd International Conference on Protective Structures, Newcastle.

Li, J, Wu, C & Hao, H 1970, 'Blast resistance of UHPC slabs-an experimental and numerical study', Proceedings of the 11th International Conference on Shock & Impact Loads on Structures, 11th International Conference on Shock & Impact Loads on Structures, CI-Premier Pte Ltd, Ottawa.

Li, J, Wu, C & Hao, H 1970, 'Concrete spall damage of UHPC slabs under contact detonation - An experimental investigation', Proceedings of the Second International Conference on Performance-based and Life-cycle Structural Engineering (PLSE 2015), International Conference on Performance-based and Life-cycle Structural Engineering, School of Civil Engineering, The University of Queensland.
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Mirmomeni, M, Heidarpour, A, Zhao, X-L, Packer, JA & Wu, C 1970, 'Mechanical Properties of Structural Steel under Post-Impact Fire', Structures Congress 2015, Structures Congress 2015, American Society of Civil Engineers, Portland, Oregon, pp. 87-98.
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Accurate prediction of material properties under combined high strain rate and elevated temperature are essential for safe design of structures to withstand post-impact fire situations such as collision by heavy vehicles followed by fire. Numerous material tests performed in recent years do not address the influence of such sequential loading on the mechanical properties of mild steel. An inclusive test program is carried out in the Civil Engineering Lab at Monash University to investigate the post-impact fire properties of Grade 350 structural steel and the results are presented here. Specimens have undergone interrupting high strain rate tensile loading, controlled locally at defined levels of elongation, to account for different deformation states. Different damage levels are introduced for each rate of strain with respect to the displacement corresponding to the ultimate stress (fu). Subsequently, the partly damaged specimens are subjected to static tensile loading to failure at high temperature conditions. Material behaviour of pre-damaged steel is compared to those of each individual loading scenario and to design code expressions. The test results demonstrate that the combined actions are profoundly different from that in which the structure is subjected to either high strain rate or thermal loading and notably vary from those predicted in different codes. Moreover, it is shown that the strength and ductility of mild steel are significantly dependent on the rate of loading, the pre-deformation history and the temperature it is subsequently exposed to. The experimental results can be used by researchers and structural engineers as benchmark data for calibrating current material model constants and/or developing new material models which take into account the coupled effect of high strain rate and temperature for rational fire analysis and design of steel structures.

Nguyen, NP, Ngo, QH & Ha, QP 1970, 'Active control of an offshore container crane', 2015 15th International Conference on Control, Automation and Systems (ICCAS), 2015 15th International Conference on Control, Automation and Systems (ICCAS), IEEE, Busan, Korea, pp. 773-778.
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Open sea loading/unloading cargos provides a potential solution to tack the problem related with port construction, expansion and congestion. This process involves a crane attached to a mobile harbor (MH) which can dynamically handle container from a large container anchored in deep water. The control objective during the operation is to maintain the payload in the desired position in the presence of ocean waves. This paper presents a robust control strategy for trajectory tracking and sway suppression of an offshore container crane. A fuzzy sliding mode control law is proposed for that. Experimental results are provided to indicate the efficiency of the proposed control strategy.

Oduro, SD, Metia, S, Duc, H & Ha, QP 1970, 'Predicting Carbon Monoxide Emissions with Multivariate Adaptive Regression Splines (MARS) and Artificial Neural Networks (ANNs)', Proceedings of the International Symposium on Automation and Robotics in Construction (IAARC), 32nd International Symposium on Automation and Robotics in Construction, International Association for Automation and Robotics in Construction (IAARC), Oulu, Finland, pp. 1-9.
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Emissions from motor vehicles need to be predicted fairly accurately to ensure an appropriate air quality management plan. This research work explores the use of a nonparametric regression algorithm known as the multivariate adaptive regression splines (MARS) in comparison with the artificial neural networks (ANN) for the purpose of best approximation of the relationship between the input and output from datasets recorded from on-board measurement and dynamometer testings. The performance of the models was evaluated by comparing the MARS and ANN predictions to the measured data using several performance indices. The results are evaluated in terms of accuracy, flexibility and computational efficiency. While MARS are more computationally efficient to reach the final model ANN are slightly more accurate. The proposed techniques may be used to assist in a decision-making policy regarding urban air pollution.

Su, Y, Li, J & Wu, C 1970, 'SHPB Test on UHPC with Steel Fibre Reinforcement', 3rd International Conference of Protective Structures, Newcastle.

Su, Y, Li, J, Wu, C, Wu, P & Liu, Z 1970, 'Dynamic Behaviour of UHPC Mixed with Nano Material', Fifth International Conference on Design and Analysis of Protective Structures, Singapore.

Wang, J & Luo, X 1970, 'Purposive Sample Consensus: A Paradigm for Model Fitting with Application to Visual Odometry', Springer Tracts in Advanced Robotics, International Conference on Field and Service Robotics, Springer International Publishing, Brisbane, Australia, pp. 335-349.
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© Springer International Publishing Switzerland 2015. ANSAC (random sample consensus) is a robust algorithm for model fitting and outliers' removal, however, it is neither efficient nor reliable enough to meet the requirement of many applications where time and precision is critical. Various algorithms have been developed to improve its performance for model fitting. A new algorithm named PURSAC (purposive sample consensus) is introduced in this paper, which has three major steps to address the limitations of RANSAC and its variants. Firstly, instead of assuming all the samples have a same probability to be inliers, PURSAC seeks their differences and purposively selects sample sets. Secondly, as sampling noise always exists; the selection is also according to the sensitivity analysis of a model against the noise. The final step is to apply a local optimization for further improving its model fitting performance. Tests show that PURSAC can achieve very high model fitting certainty with a small number of iterations. Two cases are investigated for PURSAC implementation. It is applied to line fitting to explain its principles, and then to feature based visual odometry, which requires efficient, robust and precise model fitting. Experimental results demonstrate that PURSAC improves the accuracy and efficiency of fundamental matrix estimation dramatically, resulting in a precise and fast visual odometry.

Xu, R & Fatahi, B 1970, 'Three Dimensional Numerical Analysis of Seismic Soil-Structure Interaction Considering Soil Plasticity', The New Zealand Geotechnical Society (NZGS), INTERNATIONAL CONFERENCE ON EARTHQUAKE GEOTECHNICAL ENGINEERING, The New Zealand Geotechnical Society (NZGS), Christchurch, New Zealand.