Publications

Boyd-Weetman, B, Thomas, P, DeSilva, P & Sirivivatnanon, V 2023, 'Accelerated Mortar Bar Test to Assess the Effect of Alkali Concentration on the Alkali–Silica Reaction' in Lecture Notes in Civil Engineering, Springer Nature Singapore, pp. 233-239.
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AbstractWe report the outcomes of a study into the influence of alkali concentration on expansion induced by the alkali–silica reaction (ASR), a deleterious reaction that causes cracking and durability loss in concrete structures. We assessed the effect of alkali concentration on mortar bar expansion using a modified form of AS1141.60.1, the accelerated mortar bar test (AMBT). Mortar prisms were prepared with a reactive aggregate and immersed in alkali solutions of varying concentrations (from 0.4 to 1.0 M NaOH) and saturated limewater at 80 °C. Expansion was monitored for 28 days. The degree of expansion was observed to increase with increasing alkali concentration and an induction period prior to expansion was observed for the 0.4 M NaOH. No expansion was observed for mortar bars immersed in the control saturated lime water bath. Additionally, no expansion was observed for mortars using blended cements containing fly ash (FA) and ground granulated blast furnace slag, suggesting the AMBT is a viable technique for demonstrating the efficacy of mitigation strategies.

Dangol, S, Li, J, Sirivivatnanon, V & Kidd, P 2023, 'Influence of Reinforcement on the Loading Capacity of Geopolymer Concrete Pipe' in Lecture Notes in Civil Engineering, Springer Nature Singapore, pp. 165-175.
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AbstractGeopolymer concrete is emerging as a sustainable construction material due to utilization of industrial by-products, which greatly reduces its carbon footprint. Past studies of the mechanical properties and resistance to sulfuric acid reaction of cement-less geopolymer concrete indicated its suitability for precast concrete pipes over ordinary Portland cement (OPC) concrete. In the present study, a three-dimensional finite element (FE) model of reinforced concrete pipe was developed using commercial software ANSYS-LSDYNA. The load-carrying capacity of reinforced and non-reinforced geopolymer concrete pipes under the three-edge bearing (TEB) test was investigated and compared with OPC concrete pipes. The results indicated geopolymer concrete with comparable compressive strength to OPC concrete showed higher loading capacity in a pipe structure due to its better tensile performance. The effect of steel reinforcement area on the loading capacity of geopolymer concrete pipes was quantitatively analyzed, and they met the specified strength requirement for OPC concrete in the ASTM standard, with up to 20% reduction in the reinforcement area.

Dong, WK, Li, WG, Lin, XQ & Shah, SP 2023, 'Investigation on Superhydrophobicity and Piezoresistivity of Self-sensing Cement-Based Sensors Using Silane Surface Treatment' in Lecture Notes in Civil Engineering, Springer Nature Singapore, pp. 17-22.
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AbstractCement-based sensors are highly susceptible to the effects of watery environments due to the hydrophilic properties of the cement matrix. In this paper, we applied a surface treatment using a silane/isopropanol solution to graphene/cement-based sensors to achieve superhydrophobicity and mitigate piezoresistive instability in watery environments. After treatment, impressive water contact angles of 163.4° and 142.0° were achieved for the surface and inner cement-based sensors, respectively. Moreover, the piezoresistivity of the coated cement-based sensors exhibited greater stability compared to their untreated counterparts. These results provide valuable insights into the piezoresistivity of hydrophobic cement-based sensors in moist environments, offering promising prospects for future structural health monitoring applications.

Nsiah-Baafi, E, Tapas, MJ, Vessalas, K, Thomas, P & Sirivivatnanon, V 2023, 'Characterization of the Nano- and Microscale Deterioration Mechanism of the Alkali–Silica Reaction in Concrete Using Neutron and X-ray Scattering Techniques: A Review' in Lecture Notes in Civil Engineering, Springer Nature Singapore, pp. 469-477.
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AbstractAlkali–silica reaction (ASR) is one of the most recognized chemical reactions that lead to the deterioration and premature failure of concrete. The severity of ASR is largely dependent on the expansive nature of the reaction product (ASR gel). As such, it is important to expound the developed knowledge on the formation, structure, composition, and swelling mechanism of ASR gel, to provide a greater understanding of ASR deterioration and to facilitate the development of more reliable prediction and mitigation methods. We present a summary of existing methods for assessing ASR and the state-of-the-art techniques that use neutron and X-ray scattering methods to characterize the nano- and microstructural properties of concrete and elucidate the potential transport dynamics of reactants that determine the mechanism and extent of ASR.

Ramu, YK, Thomas, PS, Vessalas, K & Sirivivatnanon, V 2023, 'Submicroscopic Evaluation Studies to Minimize Delayed Ettringite Formation in Concrete for a Sustainable Industry and Circular Economy' in Lecture Notes in Civil Engineering, Springer Nature Singapore, pp. 445-455.
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AbstractThe high cost of maintenance, repair and retrofitting of concrete infrastructure to keep these structures durable and serviceable is not sustainable, so the design process needs to consider all aspects of deterioration mechanism/s that can potentially occur in a concrete structure. The ideal solution should contribute to sustainability by enhancing the durability of concrete elements and supporting a circular economy. We studied delayed ettringite formation (DEF), a potential deterioration mechanism, including mitigation measures, in various heat-cured cementitious systems. The results showed that continuously connected pore/crack paths at the submicroscopic level favor the transportation of DEF-causing ions in heat-cured systems. DEF increases the chance of developing cracks, which is a durability concern. To mitigate DEF, fly ash produced from an Australian bituminous coal-burning power station was incorporated in the binder to support the circular economy concept. Changes in heat-cured cementitious systems were evaluated using expansion, electrical resistivity, dynamic modulus, and microstructural studies. The pozzolanicity of fly ash was found to greatly enhance the formation of denser calcium-silica-hydrate, which in turn restricted the transportation of DEF-causing ions at the submicron level, leading to less DEF occurrence and enhancement of the durability and sustainability of concrete in field structures.

Samali, B, Yu, Y, Li, Y, Li, J & Li, H 2023, 'The Impact of Smart Materials on Structural Vibration Control' in Automation in Construction toward Resilience, CRC Press, pp. 57-72.
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The future development of smart materials in the areas, such as self-tuning vibrating energy harvesting devices, self-sustainable networks, and earthquake protection devices, is of significant importance. With the great potential to develop smart structures, smart material includes shape memory alloy, piezoelectric, magnetorheological (MR) and electrorheological (ER) materials, which possess stimulus responses. Accordingly, smart materials can be regarded as promising candidates for adaptive device development for structural vibration mitigation application. In this chapter, the smart material classification and potential applications are reviewed first. Then, a case study is conducted to comprehensively illustrate application of MR material-based semi-active control device in structural seismic protection. Finally, the challenges and future work on this topic are briefly analysed and discussed.

Tapas, MJ, Yan, A, Thomas, P, Holt, C & Sirivivatnanon, V 2023, 'Effect of Carbonation on the Microstructure and Phase Development of High-Slag Binders' in Lecture Notes in Civil Engineering, Springer Nature Singapore, Switzerland, pp. 213-221.
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AbstractThe drive for sustainable concrete production favors the use of high replacement levels of supplementary cementitious materials (SCMs) in the concrete mix. The use of SCMs such as fly ash and slag, however, although they improve the sustainability of concrete production as well as most concrete durability properties, increases the carbonation rate. Carbonation decreases the pH of the concrete pore solution, making the steel reinforcement susceptible to corrosion. The effect of carbonation is, however, not confined to the change in pH of the pore solution. We investigated changes in the microstructure and phases of high-slag binders due to carbonation. The carbonation resistance of mortars with 50 and 70% slag replacement were investigated at exposure conditions of 2%CO2, 50%RH, 23 °C. The carbonated and non-carbonated parts of the mortars were subjected to various characterization techniques to investigate the effect of carbonation on microstructure and phase development. Results confirmed the absence of portlandite in all the carbonated regions (“colorless” by phenolphthalein test, which indicated that the change in color of the phenolphthalein solution was due to the absence of portlandite to buffer the pH). Significant reduction in the amount of C-S-H, as well as increase in the amount of calcium carbonate, were been observed in the carbonated regions. Aragonite, a polymorph of CaCO3, was very prominent in all the carbonated mortars.

Adnan Farooq, M & Nimbalkar, S 2023, 'Novel sustainable base material for concrete slab track', Construction and Building Materials, vol. 366, pp. 130260-130260.
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Bahmani, H, Mostafaei, H, Ghiassi, B, Mostofinejad, D & Wu, C 2023, 'A comparative study of calcium hydroxide, calcium oxide, calcined dolomite, and metasilicate as activators for slag-based HPC', Structures, vol. 58, pp. 105653-105653.
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Chen, D, Wu, C & Li, J 2023, 'Assessment of modeling methods for predicting load resulting from hydrogen-air detonation', Process Safety and Environmental Protection, vol. 180, pp. 752-765.
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Chen, D, Wu, C, Li, J & Liao, K 2023, 'An overpressure-time history model of methane-air explosion in tunnel-shape space', Journal of Loss Prevention in the Process Industries, vol. 82, pp. 105004-105004.
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This study investigated methane-air explosion in tunnel-shape space and developed an overpressure-time history model based on numerical results. The findings revealed that for the progressively vented gas explosion with movable steel obstacles in a 20 m long tunnel, the inner peak overpressure increased as the activation pressure of the tunnel top cover got higher but remained below 6 bar. However, as the activation pressure increased to 8 bar or higher, the peak inner overpressure remained unchanged. As the segment cover panel became wider, the peak pressure was almost unchanged, but the pressure duration and impulse declined significantly. The peak pressure and impulse increased as the tunnel length vary from 10 to 30 m. With fixed tunnel length, higher blast pressure but lower impulse was observed as the inner obstacles were closer or the activation pressure of obstacles was higher. It is also found that a local enlarged space in the tunnel enhanced the peak pressure significantly. An overpressure time history model for the tunnel with fixed top cover and enlarged end zone was established. The model considered activation pressure of vent cover, area and length of vent opening, methane concentration, number and blockage ratio of fixed obstacles was developed to calculate the overpressure and corresponding time at characteristic points of the pressure-history curve. The cubic Hermite interpolation algorithm and a specially tuned formula consisting of the power and exponential function were used to interpolate pressure values between characteristic points. The proposed model can predict both the peak pressure and the overpressure time history with acceptable accuracy.

Chen, Q, Rong, H, Tao, G, Nimbalkar, S & Xie, K 2023, 'Fatigue characteristics of nano-SiO2 cemented soil under coupled effects of dry-wet cycle and seawater corrosion', Construction and Building Materials, vol. 401, pp. 132579-132579.
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Chen, Q, Xie, K, Tao, G, Nimbalkar, S, Peng, P & Rong, H 2023, 'Laboratory investigation of microstructure, strength and durability of cemented soil with Nano-SiO2 and basalt fibers in freshwater and seawater environments', Construction and Building Materials, vol. 392, pp. 132008-132008.
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Chen, Q, Yu, R, Gaoliang, T & Nimbalkar, S 2023, 'Microstructure, strength and durability of nano-cemented soils under different seawater conditions: laboratory study', Acta Geotechnica, vol. 18, no. 3, pp. 1607-1627.
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Chen, Q, Zhang, H, Ye, J, Tao, G & Nimbalkar, S 2023, 'Corrosion Resistance and Compressive Strength of Cemented Soil Mixed with Nano-Silica in Simulated Seawater Environment', KSCE Journal of Civil Engineering, vol. 27, no. 4, pp. 1535-1550.
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Chi, K, Li, J & Wu, C 2023, 'Numerical simulation of buried steel pipelines subjected to ground surface blast loading', Thin-Walled Structures, vol. 186, pp. 110716-110716.
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Steel gas pipelines are important component in energy sector. Due to its easy accessibility and importance, shallow-buried pipelines are becoming targets of intentional attack. Therefore, it is urgent to investigate the failure mechanism of buried pipelines subjected to ground surface blast loadings and carry out quantitative damage assessment of pipelines. The present study performs numerical simulation on the resistance of buried pipelines subjected to ground surface explosion. The simulated ground shock propagation in the soil medium was validated with technical manual TM5-855-1 as well as experimental data. The effects of charge weight, stand-off distance, explosive position offset, pipe diameter, pipe wall thickness, buried depth, and steel grade as well as different soil types were investigated. It was found that for the grade X70 pipe with the same buried depth 760 mm, the cross-sectional flattening ratio under charge weight 227 kg (typical sedan bomb) was nearly 544 times greater than the case in 2.3 kg charge weight (typical pipe bomb). The flattening ratio decreased 99.9% because of the buried depth increased from 300 mm to 1800 mm. The decrease in pipe diameter from 860 mm to 350 mm caused 89.6% reduction in flattening ratio. The increase in wall thickness from 4.80 mm to 12.7 mm caused 99.7% decline in flattening ratio. Similarly, it showed the flattening ratio decreased 29.3% when the steel grade increased from X42 (yield strength 290 MPa) to X80 (yield strength 580 MPa). The blast resistance was the worst when the pipeline was buried in clay soil, in which the flattening ratio was 74.8% and 40.3% greater as compared with sandy loam and soil medium. An analytical formula was derived to predict the flattening ratio of pipelines against surface explosion.

Cui, J, Rao, P, Li, J, Chen, Q & Nimbalkar, S 2023, 'Time-dependent evolution of bearing capacity of driven piles in clays', Proceedings of the Institution of Civil Engineers - Geotechnical Engineering, vol. 176, no. 4, pp. 402-418.
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Analysis of the time-dependent variation in the axial capacity of driven piles is difficult yet critical for geotechnical engineers. In this work, to investigate the short-term evolution of the bearing capacity of driven piles, a two-dimensional finite-element (FE) model was developed using the Abaqus program. Pile installation, soil consolidation and loading were incorporated in an integrated FE model. Changes in the excess pore pressure and the void ratio of the surrounding soil were investigated to evaluate the consolidation mechanism. The findings revealed that excess pore water pressure dissipation was the primary cause of the short-term evolution of the pile's bearing capacity. The dissipation of excess pore water pressure lowered the void ratio and increased the strength and stiffness of the surrounding soil. The effect of the permeability coefficient was also assessed. The permeability coefficient was found to affect the rate of evolution but not its magnitude. A centrifuge model test was used to verify the numerical results. The findings of this study may serve as a guide for improved design and construction of driven piles.

Deng, Z, Li, W, Dong, W, Sun, Z, Kodikara, J & Sheng, D 2023, 'Multifunctional asphalt concrete pavement toward smart transport infrastructure: Design, performance and perspective', Composites Part B: Engineering, vol. 265, pp. 110937-110937.
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Fan, J, Yan, J, Zhou, M, Xu, Y, Lu, Y, Duan, P, Zhu, Y, Zhang, Z, Li, W, Wang, A & Sun, D 2023, 'Heavy metals immobilization of ternary geopolymer based on nickel slag, lithium slag and metakaolin', Journal of Hazardous Materials, vol. 453, pp. 131380-131380.
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To solve heavy metals leaching problem in the utilization of various industrial solid wastes, this work investigated the heavy metals immobilization of ternary geopolymer prepared by nickel slag (NS), lithium slag (LS), and metakaolin (MK). Compressive strength was measured to determine the optimum and appropriate mix proportions. The leaching characteristics of typical heavy metals (Cu (Ⅱ), Pb (Ⅱ), and Cr (Ⅲ)) in acid, alkali, and salt environments were revealed by Inductively Coupled Plasma (ICP). The heavy metals immobilization mechanism was explored by Mercury Intrusion Porosimetry (MIP), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) tests. The experimental results show that the group with a mass ratio of NS, LS and MK of 1:1:8 exhibits the highest compressive strength, which reaches 69.1 MPa at 28 d. The ternary geopolymer possesses a desirable capacity for immobilizing inherent heavy metals, where the immobilization rates of Cu and Pb reach 96.69 %, and that of Cr reaches 99.97 %. The leaching concentrations of Cr and Pb increase when the samples are exposed to acidic and alkaline environments. Cu and Pb are mainly physically encapsulated in geopolymer. Additionally, immobilization of Cr mainly involves physical encapsulation and chemical bonding.

Gomes, SDC, Nguyen, QD, Li, W & Castel, A 2023, 'Carbonation resistance of calcined clay-ground granulated blast furnace slag alkali-activated mortar', Construction and Building Materials, vol. 393, pp. 131811-131811.
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Guo, Y, Lei, B, Yu, L, Lin, X & Li, W 2023, 'Investigation on mechanical properties and failure criterion of multi-recycled aggregate concrete under triaxial compression', Procedia Structural Integrity, vol. 45, pp. 66-73.
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Hang, J, Wu, Y, Li, Y, Lai, T, Zhang, J & Li, Y 2023, 'A deep learning semantic segmentation network with attention mechanism for concrete crack detection', Structural Health Monitoring, vol. 22, no. 5, pp. 3006-3026.
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In this research, an attention-based feature fusion network (AFFNet), with a backbone residual network (ResNet101) enhanced with two attention mechanism modules, is proposed for automatic pixel-level detection of concrete crack. In particular, the inclusion of attention mechanism modules, for example, the vertical and horizontal compression attention module (VH-CAM) and the efficient channel attention upsample module (ECAUM), is to enable selective concentration on the crack feature. The VH-CAM generates a feature map integrating pixel-level information in vertical and horizontal directions. The ECAUM applied on each decoder layer combines efficient channel attention (ECA) and feature fusion, which can provide rich contextual information as guidance to help low-level features recover crack localization. The proposed model is evaluated on the test dataset and the results reach 84.49% for mean intersection over union (MIoU). Comparison with other state-of-the-art models proves high efficiency and accuracy of the proposed method.

Hasan, HA, Hacheem, ZA, Almurshedi, AD & Khabbaz, H 2023, 'The Influence of Styrene Butadiene Latex on Sandy Soil Reinforced by Soil Mixed Columns under Raft Foundation', Mathematical Modelling of Engineering Problems, vol. 10, no. 3, pp. 733-739.
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Hong, Z, Tao, M, Cui, X, Wu, C & Zhao, M 2023, 'Experimental and numerical studies of the blast-induced overbreak and underbreak in underground roadways', Underground Space, vol. 8, pp. 61-79.
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Hong, Z, Tao, M, Liu, L, Zhao, M & Wu, C 2023, 'An intelligent approach for predicting overbreak in underground blasting operation based on an optimized XGBoost model', Engineering Applications of Artificial Intelligence, vol. 126, pp. 107097-107097.
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Hong, Z, Tao, M, Wu, C, Zhou, J & Wang, D 2023, 'The spatial distribution of excavation damaged zone around underground roadways during blasting excavation', Bulletin of Engineering Geology and the Environment, vol. 82, no. 4, p. 155.
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Knowledge of the degree and depth of the excavation damaged zone (EDZ) resulting from drill-and-blast excavations has important influences on the design and construction of deep underground tunnels. However, the spatial distribution of EDZ around underground tunnels subjected to the combined effect of blast loading and in situ stress unloading is still under discussion. In this study, the dependences of the spatial distribution of EDZ in an underground tunnel on the variations of in situ stress conditions, excavation dimensions and rock strength were investigated using a combined method of field measuring and numerical modelling. Field measurements of EDZ in an underground mine were first conducted using the non-metallic acoustic technique. Subsequently, a blast excavation model concerning the combined effect of blast loading and in situ stress unloading was developed and calibrated against the field-measured data. Finally, the EDZs induced by various in situ stress conditions, tunnel shapes, and dimensions as well as rock strengths were simulated. The field measurement results indicate that larger highly damaged zones are generated at the roadway crown and sidewall, whereas smaller intensively damaged zones are induced at the roadway shoulder. The average depth of EDZ around the tested roadways, with an overburden of 355 m to 915 m, varies from 0.36 m to 1.72 m. The numerical results show that in situ stress, excavation dimension, and rock strengths significantly impact the depth of EDZ. More specifically, lateral pressure coefficient and the shape of the roadway cross section play a predominant role in controlling the distribution pattern of EDZ, and the magnitude of in situ stress, excavation dimension, and rock strength mainly contribute to the depth of EDZ. Furthermore, the special phenomenon of zonal disintegration in the surrounding rock mass occurs around highly pre-stressed underground roadways.

Hong, Z, Tao, M, Zhao, M, Zhou, J, Yu, H & Wu, C 2023, 'Numerical modelling of rock fragmentation under high in-situ stresses and short-delay blast loading', Engineering Fracture Mechanics, vol. 293, pp. 109727-109727.
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Islam, MS, Molley, TG, Hung, T-T, Sathish, CI, Putra, VDL, Jalandhra, GK, Ireland, J, Li, Y, Yi, J, Kruzic, JJ & Kilian, KA 2023, 'Magnetic Nanofibrous Hydrogels for Dynamic Control of Stem Cell Differentiation', ACS Applied Materials & Interfaces, vol. 15, no. 44, pp. 50663-50678.
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Jahandari, S, Tao, Z, Alim, MA & Li, W 2023, 'Integral waterproof concrete: A comprehensive review', Journal of Building Engineering, vol. 78, pp. 107718-107718.
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Karbassiyazdi, E, Altaee, A, Razmjou, A, Samal, AK & Khabbaz, H 2023, 'Gravity-driven composite cellulose acetate/activated carbon aluminium-based hydrogel membrane for landfill wastewater treatment', Chemical Engineering Research and Design, vol. 200, pp. 682-692.
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Ke, Y, Shi, FL, Zhang, SS, Nie, XF & Li, WG 2023, 'Strength Model for Debonding Failure in RC Beams Flexurally Strengthened with NSM FRP and Anchored with FRP U-Jackets', Journal of Composites for Construction, vol. 27, no. 5.
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The flexural performance of reinforced concrete (RC) beams could be effectively improved by applying a near-surface mounted (NSM) fiber-reinforced polymer (FRP) at the beam soffit. However, such NSM FRP flexurally-strengthened beams frequently failed due to FRP debonding, which limited the full utilization of the FRP strength. In some experimental studies, FRP U-jackets have been used as the anchorage to mitigate or prevent debonding failures in NSM FRP flexurally-strengthened beams. These studies showed excellent anchoring performance of the FRP U-jackets. The authors recently developed a finite-element (FE) approach that could accurately predict the behavior of RC beams that had been flexurally strengthened with NSM FRP (NSM-strengthened beams), which were anchored with FRP U-jackets. Based on a parametric study that was undertaken, which used the simplified version of the FE approach, this paper proposed a strength model for the most common debonding failure mode in NSM-strengthened beams with FRP U-jackets. The proposed strength model consisted of an equation for the maximum NSM FRP strain (Ef) at debonding failure. Once the maximum FRP strain was known, the load-carrying capacity of the strengthened beam could be obtained through a section analysis. Comparing the predictions made by the proposed strength model with the test results showed that the proposed strength model could provide close predictions.

Lal Mohammadi, E, Khaksar Najafi, E, Zanganeh Ranjbar, P, Payan, M, Jamshidi Chenari, R & Fatahi, B 2023, 'Recycling industrial alkaline solutions for soil stabilization by low-concentrated fly ash-based alkali cements', Construction and Building Materials, vol. 393, pp. 132083-132083.
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Le, T, Desa, S & Khabbaz, H 2023, 'The Influence Of Bagasse Fly Ash Particle Size In Controlling Expansive Soils In Combination With Hydrated Lime', Australian Geomechanics Journal, vol. 58, no. 1, pp. 47-57.
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Sugarcane is the second largest export crop in Australia. Industrial production of sugar, from sugarcane, results in bagasse fly ash (BFA), a by-product from the cogeneration in sugar milling operations that generate electricity by steam. The chemical and physical properties of BFA highlight its potential as a promising pozzolan for the stabilization of expansive soils, due primarily to a high content and surface area of the amorphous silicate found in BFA. Silicate in bagasse fly ash reacts extensively with calcium hydrate in lime to produce hydrated products via pozzolanic reactions, this results in a hardening of the material to which BFA and lime have been added. This reaction has been studied to be a function of the size of BFA particles and conditions of the curing process. This study explored the variables that influence the reaction and evaluated shrinkage and compressive strength of the mixtures to which bagasse fly ash, in the form of different particle size distributions, and hydrated lime are added. The maximum BFA particles sizes considered within this study include 75, 150 and 425 μm; curing times of 7 and 28 days are also explored. A suite of testing, including Atterberg limits, linear shrinkage (LS), and unconfined compressive strength (UCS) tests were completed on the prepared mixtures. The findings indicate that bagasse fly ash with a maximum size of 425 μm yields a higher UCS and lower LS, compared to finer BFA particle mixtures. The ash with a maximum particle size of 425-μm also improves the ductility of treated soils and accelerates their strength gain, compared to soil- lime stabilized samples. The results of the study build towards a better understanding of BFA, and the ways in which such a material maybe engineered to replace concrete in road work projects and other applications involving expansive soils.

Lei, B, Xiong, Q, Zhao, H, Dong, W, Tam, VWY, Sun, Z & Li, W 2023, 'Performance of asphalt mortar with recycled concrete powder under different filler-to-asphalt weight ratios', Case Studies in Construction Materials, vol. 18, pp. e01834-e01834.
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The feasibility of using recycled concrete powder (RCP) as fillers in asphalt mortar is investigated in this study, to achieve a sustainable and economical asphalt production. The differences in physical properties between limestone powder (LSP) and RCP are analyzed and compared. Moreover, the interactions of LSP and RCP with asphalt are studied as well. The properties of asphalt mortar studied include ductility, softening point, penetration, viscous and elastic behaviors of asphalt mortar. Compared to LSP, the RCP presented a rougher surface, additional pores, more complex pore structures, larger Brunauer, Emmett and Teller (BET) surface areas, and smaller particle size. At 0.6 and 0.9 of filler-to-asphalt weight ratio (F/A), the RCP is more effective for the performance enhancement of asphalt mortar compared with the LSP. When the F/A is 0.9 and LSP is completely replaced by RCP, the 15 °C penetration index (PI) and ductility of asphalt mortar decrease by 9.3% and 29.2% respectively. The softening point increases by 5.4%. By contrast, the RCP causes a considerable decrease in PI, equivalent brittle point (T1.2) and ductility when F/A ratio is 1.2. After RCP completely replace LSP, the PI, T1.2, and ductility of asphalt mortar decrease by 47.1%, 44.0%, and 29.0%, respectively. However, at F/A of 0.6, the asphalt mortar with 100% RCP replacement ratio presented both acceptable ductility and plasticity. Under the same temperature and F/A, the complex shear modulus G* and rutting resistance factor G* /sinδ of asphalt mortar raise with the increase of RCP replacement, which indicates that the RCP can better enhance the high-temperature rutting resistance of asphalt mortar than the counterpart LSP. It also implies that the modification of LSP and RCP in asphalt mortar mainly depends on the physical interactions rather than the chemical reactions.

Lei, B, Yu, H, Guo, Y, Dong, W, Liang, R, Wang, X, Lin, X, Wang, K & Li, W 2023, 'Fracture behaviours of sustainable multi-recycled aggregate concrete under combined compression-shear loading', Journal of Building Engineering, vol. 72, pp. 106382-106382.
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Lei, B, Yu, H, Guo, Y, Zhao, H, Wang, K & Li, W 2023, 'Mechanical properties of multi-recycled aggregate concrete under combined compression-shear loading', Engineering Failure Analysis, vol. 143, pp. 106910-106910.
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The mechanical properties and strength failure criteria of multi-recycled aggregate concrete (multi-RAC) under combined compression and shear loading states are investigated in this paper. The peak shear strength, peak shear displacement, and failure patterns are compared under different regeneration cycles and normal compressive stress ratios. The results reveal that both the peak shear strength and peak shear displacement increase with the increased normal stress ratio. The shear failure pattern with higher severity corresponds to more spalling powder and debris deposited on the shear fracture surface. When the regeneration cycles of coarse aggregate increase, the peak shear strength decreases and the descending trend become more evident with the higher vertical compressive stress ratio. Under the normal compressive stress, contact friction strength is the dominant component of peak shear strength among the cohesive strength, contact friction strength, and shear dilation strength. Based on different stress expressions, three compression-shear failure criterion models considering the regeneration cycles of coarse aggregate under planar stress state were established for RAC. The stress invariance failure criterion model and octahedral stress failure criterion model in quadratic parabolic functional form can provide high prediction accuracies.

Lei, B, Yu, L, Guo, Y, Mahmood, AH, Qu, F, Wang, X & Li, W 2023, 'Failure behaviour and damage evolution of multi-recycled aggregate concrete under triaxial compression', Engineering Failure Analysis, vol. 153, pp. 107572-107572.
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Leng, D, Wang, R, Yang, Y, Li, Y & Liu, G 2023, 'Study on a three-dimensional variable-stiffness TMD for mitigating bi-directional vibration of monopile offshore wind turbines', Ocean Engineering, vol. 281, pp. 114791-114791.
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Li, K, Li, X, Chen, Q & Nimbalkar, S 2023, 'Laboratory Analyses of Noncoaxiality and Anisotropy of Spherical Granular Media under True Triaxial State', International Journal of Geomechanics, vol. 23, no. 9.
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Li, P, Li, W, Wang, K, Zhao, H & Shah, SP 2023, 'Hydration and microstructure of cement paste mixed with seawater – An advanced investigation by SEM-EDS method', Construction and Building Materials, vol. 392, pp. 131925-131925.
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Li, P, Li, W, Wang, K, Zhou, JL, Castel, A, Zhang, S & Shah, SP 2023, 'Hydration of Portland cement with seawater toward concrete sustainability: Phase evolution and thermodynamic modelling', Cement and Concrete Composites, vol. 138, pp. 105007-105007.
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To mitigate the shortage of freshwater resource in the island and coastal regions, using seawater (SW) for concrete mix can provide significant economic and environmental benefits. To achieve a safe and reliable application, in-depth investigation is needed on hydration of Portland cement in SW. The composition of solid and liquid phases in hydrated Portland cement was quantitively determined and analysed in this study. The use of SW not only significantly increases the hydration rate of clinker but also affects the evolution of phase assemblage. Both the thermodynamic calculations and experimental determinations indicates the formation of Friedel's salt (FS) instead of sulfo-AFm in hydrated cement by SW, implying sulfate ions cannot compete with chloride ions to combine with AFm phases. The characteristic reaction in SW leads to higher sulfate concentration, thus indirectly hindering ettringite (AFt) conversion at the late stage. Through the experimental quantification of thermogravimetric analysis and X-ray diffraction analysis, the kinetic model of clinker dissolution was modified to be more suitable for the hydration of Portland cement in SW. The calculation from coupled models exhibits a novel method to evaluate the evolution of phases in cement hydration. Through model calculations, 3.70% higher solid volume and 12.2% lower liquid volume were obtained in the cement-SW paste at the end of the hydration, which may cause the mechanical properties to be more sensitive under environmental humidity and the temperature.

Lin, S, Kong, X, Wang, J & Liu, A 2023, 'Helix-HPSO approach for UAV path planning in a multi-building environment', Journal of Reliable Intelligent Environments, vol. 9, no. 4, pp. 371-384.
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Regular inspection of historic buildings is essential, while path planning of the building inspection is challenging because it requires comprehensive coverage at a low cost. Most of the previous research does not consider the multiple buildings’ environment. In this paper, a three-dimensional path planning approach is proposed to provide the inspection for multiple buildings. The proposed Helix-HPSO approach generates the helix-shaped path for each building and uses HPSO for path planning between buildings. The computational experiment validates the proposed approach. The helix-shaped path costs less than the traditional back-and-forth path for building inspection. HPSO is compared with other bio-inspired algorithms for optimization problems and PSO for path planning.

Lin, S, Liu, A, Wang, J & Kong, X 2023, 'An intelligence-based hybrid PSO-SA for mobile robot path planning in warehouse', Journal of Computational Science, vol. 67, pp. 101938-101938.
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Mobile robots play crucial roles in industry and commerce, and automatic guided vehicles (AGV) are one of the primary parts of smart manufactory and intelligent logistics. Path planning is the core task for the AGV system, and it generates the path from origin to destination. The motivation of the study is to improve the scalability, flexibility, adaptability, and performance of the robot path planning systems. We propose the hybrid PSO-SA algorithm for the optimization of AGV path planning. Compared with other heuristic algorithms by benchmark functions, including HS, FA, ABC and GA, the proposed algorithm shows excellent performance in dealing with optimization problems. It reduces the possibility of getting trapped in one local optimum and enhances the efficiency to get the best global solution with faster convergence and less time consumption. It is evaluated with multiple cost functions and path planning with simulations and experiments. The objective of the proposed algorithm is to minimize the path length and produce a smooth path without collision. The proposed PSO-SA algorithm is compared with PSO in the path planning application, and the mean runtime and iteration times are usually significantly lower than PSO.

Lin, X, Li, W, Castel, A, Kim, T, Huang, Y & Wang, K 2023, 'A comprehensive review on self-healing cementitious composites with crystalline admixtures: Design, performance and application', Construction and Building Materials, vol. 409, pp. 134108-134108.
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Crystalline admixture (CA) has garnered attention as a promising self-healing agent for cementitious composites. This paper aims to provide a compressive review on the effects of CA on the self-healing behaviours and durability properties of cementitious composites. CA is in powder form, consisting of Portland cement and special chemicals as self-healing stimulants. Since the powder-form CA was directly mixed with the cementitious mixture, CA addition has no significant impact on the properties of fresh concrete but enhances the compressive strength of CA-cementitious composites. Furthermore, self-healing is activated by moisture, resulting in the production of calcium-based self-healing products. In terms of crack closure efficacy, CA-cementitious specimens cured under wet/dry cycle demonstrated a higher crack closure ratio than those cured under water immersion or air exposure. Specimens cured in chloride solution exhibited the best healing recovery. However, reduced mechanical recoveries are observed in specimens exposed to freeze–thaw cycles and those in chloride solution, while better mechanical recoveries are found in specimens exposed to wet/dry cycles. Overall, CA can reduce the sorptivity, permeability, chloride penetration, and the depth of sodium ions penetration, offering favourable protection for cementitious composites. Although some durability properties of CA-cementitious composites have been explored, further studies are required to investigate potential effects on shrinkage, ingress of aggressive ions, carbonation, and alkali-silica reaction (ASR). The application of CA in cementitious composites could be considered as a cost-effective approach for inducing self-healing capability, given its affordable and straightforward construction process.

Lin, X, Li, W, Guo, Y, Dong, W, Castel, A & Wang, K 2023, 'Biochar-cement concrete toward decarbonisation and sustainability for construction: Characteristic, performance and perspective', Journal of Cleaner Production, vol. 419, pp. 138219-138219.
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Liu, J, He, Z, Liu, P, Wei, J, Li, J & Wu, C 2023, 'High-velocity projectile impact resistance of reinforced concrete slabs with ultra-high performance concrete strengthening - A numerical study', Structures, vol. 52, pp. 422-436.
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Liu, K, Li, Q, Wu, C, Li, X & Zhu, W 2023, 'Influence of In-Situ Stress on Cut Blasting of One-Step Raise Excavation Using Numerical Analysis Based on a Modified Holmquist-Johnson-Cook Model', Materials, vol. 16, no. 9, pp. 3415-3415.
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Due to different tensile and compressive properties of rock material, the corresponding tensile and compressive damage evolution show major differences. To investigate the tensile and compressive damage evolution in deep cut blasting with different in-situ stresses, an improved Holmquist-Johnson-Cook (HJC) material model considers the tensile and compressive damage separately is developed. The improved HJC model is implemented into LS-DYNA via a user-defined subroutine in this study. Then, a numerical model with different in-situ stresses loading schemes is modelled. Numerical simulation results show that in-situ stress can inhibit the development of tensile damage evolution, while promote the development of compressive damage evolution. The overall damage zone presents a decreasing trend with the increase of in-situ stress, because the tensile damage is more sensitive than the compressive damage for rock material. In addition, the maximum principal stress can determine the development of the direction of damage. Further, for a field test of blind cut raise in deep, the actual in-situ stress values are loaded on the numerical model. Then, in order to overcome the difficulties caused by in-situ stress, the cut blasting design is optimized by reducing hole spacing. Subsequently, the optimized cut parameters are applied in the blind cut raise. However, the one-step raise excavation method is adjusted to two steps to ensure success due to a serious borehole deviation between drilling and design drawing. After these steps, the formation of the blind cut raise with 8.7 m depth is met the requirements of design.

Liu, K, Liu, J, Li, J, Tao, M & Wu, C 2023, 'Experimental investigation of heating–cooling effects on the mechanical properties of geopolymer-based high performance concrete heated to elevated temperatures', Structures, vol. 47, pp. 735-747.
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In this study, geopolymer-based high performance concrete (G-HPC) reinforced with steel fibres was utilized to investigate its dynamic behaviour after heating–cooling treatment. A furnace with a heating capacity of 1100 °C was adopted to heat the specimens. The P-wave velocity and quasi-static uniaxial compressive strength of G-HPC after the heating–cooling treatment were obtained and compared with those without the heating–cooling treatment. The experimental findings indicated that the G-HPC specimens suffered different degrees of thermal damage under 250–1000 °C high temperature, while it still remained a good explosive spalling resistance. Moreover, the water cooling regime would cause more serious damage to the G-HPC specimens than the natural cooling. Further, a 50 mm-diameter Split Hopkinson Pressure Bar (SHPB) apparatus was applied to characterize the dynamic behaviour of G-HPC after the heating–cooling treatment, and a high-speed camera was employed to record the failure process. Upon increasing the temperature, the dynamic compressive strength and elastic modulus of G-HPC were deteriorated especially in the temperature range between 250 °C and 750 °C, thereby leading to partial loss of its ability to resist impact loads. However, even after being heated to 1000 °C, the specimens still demonstrated a significant strain rate effect. Besides, the high cooling rate under water was observed to induce a thermal shock, resulting in the secondary damage for the heated specimens.

Liu, Q, Tang, H, Chen, K, Sun, C, Li, W, Jiao, S & Tam, VWY 2023, 'Improving industrial drying process of recycled fine aggregates as a means of carbonation to improve the mechanical properties and plastic shrinkage of self-leveling mortar', Construction and Building Materials, vol. 403, pp. 133001-133001.
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Luo, H, Tao, M, Wu, C & Cao, W 2023, 'Dynamic response of an elliptic cylinder inclusion with imperfect interfaces subjected to plane SH wave', Geomechanics and Geophysics for Geo-Energy and Geo-Resources, vol. 9, no. 1, p. 24.
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AbstractUnderground chambers or tunnels often contain inclusions, the interface between the inclusion and the surrounding rock is not always perfect, which influences stress wave propagation. In this study, the imperfect interface and transient seismic wave were represented using the spring model and Ricker wavelet. Based on the wave function expansion method and Fourier transform, an analytical formula for the dynamic stress concentration factor (DSCF) for an elliptical inclusion with imperfect interfaces subjected to a plane SH-wave was determined. The theoretical solution was verified via numerical simulations using the LS-DYNA software, and the results were analyzed. The effects of the wave number (k), radial coordinate (ξ), stiffness parameter (β), and differences in material properties on the dynamic response were evaluated. The numerical results revealed that the maximum DSCF always occurred at both ends of the elliptical minor axis, and the transient DSCF was generally a factor of 2–3 greater than the steady-state DSCF. Changes in k and ξ led to variations in the DSCF value and spatial distribution, changes in β resulted only in variations in the DSCF value, and lower values of ωp and β led to a greater DSCF under the same parameter conditions. In addition, the differences in material properties between the medium and inclusion significantly affected the variation characteristics of the DSCF with k and ξ.

Ma, M, Tam, VW, Le, KN, Butera, A, Li, W & Wang, X 2023, 'COMPARATIVE ANALYSIS ON INTERNATIONAL CONSTRUCTION AND DEMOLITION WASTE MANAGEMENT POLICIES AND LAWS FOR POLICY MAKERS IN CHINA', JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT, vol. 29, no. 2, pp. 107-130.
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In the current age of enhanced environmental awareness, transformation to sustainable management in the construction sector is needed. China currently produces the largest amount of construction and demolition (C&D) waste around the world, but the average recovery rate of the waste was only about 5% in 2017. In order to investigate problems in current C&D waste management in China, a cross-national comparative analysis is conducted among China and seven selected countries (Japan, South Korea, Germany, Italy, Austria, the Netherlands and the United Kingdom), to compare legal texts of national policies and laws which relate to C&D waste management and are currently being used. Through the comparison, problems in management of C&D waste in China are investigated. The problems could be concluded to: (a) inadequate guidance on recycling, (b) lack of market incentives in utilising recycled materials, (c) incomplete knowledge of stakeholders’ responsibilities, (d) lack of penalty for other stakeholders, and (e) inefficient supervision system. By understanding these problems, this paper further provides recommendations to enhance the performance of C&D waste management in China.

Mostafaei, H, Bahmani, H, Mostofinejad, D & Wu, C 2023, 'A novel development of HPC without cement: Mechanical properties and sustainability evaluation', Journal of Building Engineering, vol. 76, pp. 107262-107262.
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Mostafaei, H, Keshavarz, Z, Rostampour, MA, Mostofinejad, D & Wu, C 2023, 'Sustainability Evaluation of a Concrete Gravity Dam: Life Cycle Assessment, Carbon Footprint Analysis, and Life Cycle Costing', Structures, vol. 53, pp. 279-295.
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Mostafaei, H, Mostofinejad, D, Ghamami, M & Wu, C 2023, 'A new approach of ensemble learning in fully automated identification of structural modal parameters of concrete gravity dams: A case study of the Koyna dam', Structures, vol. 50, pp. 255-271.
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Mostafaei, H, Mostofinejad, D, Ghamami, M & Wu, C 2023, 'Fully automated operational modal identification of regular and irregular buildings with ensemble learning', Structures, vol. 58, pp. 105439-105439.
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Nguyen, CC, Thai, MT, Hoang, TT, Davies, J, Phan, PT, Zhu, K, Wu, L, Brodie, MA, Tsai, D, Ha, QP, Phan, H-P, Lovell, NH & Nho Do, T 2023, 'Development of a soft robotic catheter for vascular intervention surgery', Sensors and Actuators A: Physical, vol. 357, pp. 114380-114380.
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Nguyen, HAD & Ha, QP 2023, 'Robotic autonomous systems for earthmoving equipment operating in volatile conditions and teaming capacity: a survey', Robotica, vol. 41, no. 2, pp. 486-510.
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AbstractThere has been an increasing interest in the application of robotic autonomous systems (RASs) for construction and mining, particularly the use of RAS technologies to respond to the emergent issues for earthmoving equipment operating in volatile environments and for the need of multiplatform cooperation. Researchers and practitioners are in need of techniques and developments to deal with these challenges. To address this topic for earthmoving automation, this paper presents a comprehensive survey of significant contributions and recent advances, as reported in the literature, databases of professional societies, and technical documentation from the Original Equipment Manufacturers (OEM). In dealing with volatile environments, advances in sensing, communication and software, data analytics, as well as self-driving technologies can be made to work reliably and have drastically increased safety. It is envisaged that an automated earthmoving site within this decade will manifest the collaboration of bulldozers, graders, and excavators to undertake ground-based tasks without operators behind the cabin controls; in some cases, the machines will be without cabins. It is worth for relevant small- and medium-sized enterprises developing their products to meet the market demands in this area. The study also discusses on future directions for research and development to provide green solutions to earthmoving.

Nguyen, HAD, Ha, QP, Duc, H, Azzi, M, Jiang, N, Barthelemy, X & Riley, M 2023, 'Long Short-Term Memory Bayesian Neural Network for Air Pollution Forecast', IEEE Access, vol. 11, pp. 35710-35725.
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Nimbalkar, S & Basack, S 2023, 'Pile group in clay under cyclic lateral loading with emphasis on bending moment: Numerical modelling', Marine Georesources & Geotechnology, vol. 41, no. 3, pp. 269-284.
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Pile foundations supporting major structures are often founded in soft compressible clays. Apart from usual super-structural loading, these piles are subjected to cyclic lateral loads originating from actions of waves, ship impacts, winds or moving vehicles. Such repetitive loading induces stress reversal in adjacent soft clay initiating progressive degradation in soil strength and stiffness. This not only deteriorates the pile capacity with unacceptable displacements, the bending moments also increase. Although past studies investigated the response of single pile under lateral cyclic loading, a detailed study on pile group in clay under cyclic lateral loading with emphasis on bending moment is of immense practical interest. This paper focuses on detailed study of the response of pile group in clay under cyclic lateral loading, with emphasis on bending moment, through numerical modelling via a three-dimensional dynamic finite element (FE) approach and simplified boundary element modelling (BEM). Comparisons of computed results with available test data imply that the results obtained by 3 D dynamic FE model are better than the BEM. Extensive parametric studies with field data indicate that pile bending moment has been significantly influenced by cyclic loading parameters (number of cycles, frequency and amplitude). Relevant conclusions are drawn from the entire study.

Ouyang, P, Rao, P, Wu, J, Cui, J, Nimbalkar, S & Chen, Q 2023, 'Hydromechanical Modeling of High-Voltage Electropulse-Assisted Fluid Injection for Rock Fracturing', Rock Mechanics and Rock Engineering, vol. 56, no. 6, pp. 3861-3886.
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Pan, Y, Li, J, Zong, Z, Wu, C & Qian, H 2023, 'Experimental and numerical study on ground shock propagation in calcareous sand', International Journal of Impact Engineering, vol. 180, pp. 104724-104724.
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Peellage, WH, Fatahi, B & Rasekh, H 2023, 'Assessment of cyclic deformation and critical stress amplitude of jointed rocks via cyclic triaxial testing', Journal of Rock Mechanics and Geotechnical Engineering, vol. 15, no. 6, pp. 1370-1390.
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Punetha, P & Nimbalkar, S 2023, 'An innovative rheological approach for predicting the behaviour of critical zones in a railway track', Acta Geotechnica, vol. 18, no. 10, pp. 5457-5483.
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AbstractThe poor performance of critical zones along a railway line has long been a subject of concern for rail infrastructure managers. The rapid deterioration of track geometry in these zones is primarily ascribed to limited understanding of the underlying mechanism and scarcity of adequate tools to assess the severity of the potential issue. Therefore, a comprehensive evaluation of their behaviour is paramount to improve the design and ensure adequate service quality. With this objective, a novel methodology is introduced, which can predict the differential plastic deformations at the critical zones and assess the suitability of different countermeasures in improving the track performance. The proposed technique employs a three-dimensional geotechnical rheological track model that considers varied support conditions of the critical zone. The approach is successfully validated with published field data and predictions from finite element analysis. This methodology is then applied to a bridge-open track transition zone, where it is observed that an increase in axle load exacerbates the track geometry degradation problem. The results show that the performance of critical zones with weak subgrade can be improved by increasing the granular layer thickness. Interpretation of the predicted differential settlement for different countermeasures exemplifies the practical significance of the proposed methodology.

Punetha, P & Nimbalkar, S 2023, 'Numerical investigation on dynamic behaviour of critical zones in railway tracks under moving train loads', Transportation Geotechnics, vol. 41, pp. 101009-101009.
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Qu, F, Zhao, H, Wu, K, Liu, Y, Zhao, X & Li, W 2023, 'Phase transformation and microstructure of in-situ concrete after 20-year exposure to harsh mining environment: A case study', Case Studies in Construction Materials, vol. 19, pp. e02287-e02287.
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Ramu, YK, Thomas, PS, Sirivivatnanon, V & Vessalas, K 2023, 'Non-expansive delayed ettringite formation in low sulphate and low alkali cement mortars', Australian Journal of Civil Engineering, vol. 21, no. 1, pp. 68-79.
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Rao, P, Feng, W, Ouyang, P, Cui, J, Nimbalkar, S & Chen, Q 2023, 'Numerical Simulation of Pipeline Failure Mechanisms Under Lightning Strikes, Capturing Electric Disruption and Thermal Damage', Journal of Failure Analysis and Prevention, vol. 23, no. 5, pp. 2065-2074.
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Sakhare, A, Punetha, P, Meena, NK, Nimbalkar, S & Dodagoudar, G-R 2023, 'Dynamic behaviour of integral abutment bridge transition under moving train loads', Transportation Geotechnics, vol. 40, pp. 100989-100989.
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Transition zones, such as bridge approaches, are discontinuities along a railway line that are highly prone to differential movement due to a rapid variation of support conditions along the track. The concrete approach slabs are often provided before and after the bridges to reduce this differential movement and provide a gradual variation in track stiffness. This paper provides insights into the dynamic behaviour of an integral abutment railway bridge (IARB) transition zone consisting of approach slab under moving train loads using finite element (FE) analyses. Firstly, the FE model is successfully validated against the published field data. Subsequently, the validated model is employed to investigate the influence of parameters such as approach slab geometry (length, thickness, inclination, and shape), backfill soil type, direction of train movement and train speed. Results show that the behaviour of IARB is sensitive to the length of the approach slab, backfill soil type and train speed. The findings of this study enhance the current understanding of the behaviour of IARBs subjected to moving train loading and identify the important parameters that influence their performance.

Samadi-Boroujeni, H, Haghshenas-Adarmanabadi, A, Shayannejad, M & Khabbaz, H 2023, 'Comparison of Mohr-Coulomb and hardening soil constitutive models for simulation of settlements in the Karkheh earth dam', Australian Geomechanics Journal, vol. 58, no. 3, pp. 143-158.
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This paper presents the settlement behaviour of Karkheh earth dam during its construction and operation stages. Karkheh is one of the largest earth dams in the world in terms of its reservoir capacity and body volume. The settlement of such a large body of soil can affect the performance of the dam elements and endanger downstream areas; should a breach or failure occur in the dam, more than two million people will be affected. It is crucial to know the settlement behaviour of this structure and use the existing results to predict its future settlements and calibrate the existing stress-strain models. For anticipation of dam settlement the measured displacement from the portable probe anchor magnets installed in the dam body are compared to the results of numerical simulations. The available data cover a period of 12 years including construction, and two material impounding and operation periods of the dam. The numerical analysis is performed in 2D plane-strain conditions and two material models are used, including Mohr-Coulomb (MC) and Hardening Soil (HS) models. The comparison between the calculation results and the measured vertical deformations in the dam site reveals that the accuracy of model for the deformations in the middle levels of dam is better than those of the crest for both applied material models in construction and impounding stages. The maximum settlement differences between computed and observed values are 0.05 m for MC model and 0.01 m for HS model. For the operation stage, the error of calculated settlements for the MC model is smaller; hence the results of this model might be more reliable for prediction of future dam settlements. The similar trends, obtained from both material models, exhibit the suitability of the model parameters used in the simulations.

Shakor, P, Nejadi, S, Paul, G & Gowripalan, N 2023, 'Effects of Different Orientation Angle, Size, Surface Roughness, and Heat Curing on Mechanical Behavior of 3D Printed Cement Mortar With/Without Glass Fiber in Powder-Based 3DP', 3D Printing and Additive Manufacturing, vol. 10, no. 2, pp. 330-355.
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Shao, R, Wu, C, Li, J & Liu, Z 2023, 'Repeated impact resistance of steel fibre-reinforced dry UHPC: Effects of fibre length, mixing method, fly ash content and crumb rubber', Composite Structures, vol. 321, pp. 117274-117274.
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Shao, R, Wu, C, Li, J, Liu, Z, Wu, P & Yang, Y 2023, 'Mechanical behaviour and environmental benefit of eco-friendly steel fibre-reinforced dry UHPC incorporating high-volume fly ash and crumb rubber', Journal of Building Engineering, vol. 65, pp. 105747-105747.
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This study evaluates the impact of high-volume fly ash (HVFA) and waste crumb rubber (CR) on the mechanical property and environmental benefit of steel fibre-reinforced dry UHPC (FR-DUHPC) designed in a previous study. FA was introduced at 20–60% by mass substitution for cement with fibre dosage of 1.5 vol. %. Then, waste CR with different meshes were added as partial/completed replacements of coarse and medium sand with three volume contents of fibres (0.5%, 1.0% and 1.5%). Test results indicated that in the case of 1.5% fibre reinforcement, the increase in FA content and the addition of CR aggregate markedly reduced the density, modulus of elasticity and strength behaviour, whereas had minimal effect on the post-peak ductility of the assessed mixtures under compression and bending loads. Owing to the adopted moist/steam curing and the continuous pozzolanic reaction, the contribution of FA effect to both strengths at various ages was apparently increased and 50% of cement substitution was considered to be the most suitable FA addition in this study. For rubberized concrete reinforced with 0.5–1.5% steel fibres, the mechanical properties increased gradually with fibre dosage and curing age. However, the effect was evidently weakened with the addition of finer CR aggregate, and increasing the fibre dosage contributed to more positive impact on ductility rather than the load-carrying capacity. In summary, the flexural property benefits derived from the inclusion of steel fibre, FA and waste CR, as well as the eco-friendly benefits derived from the cost saving, energy conservation and carbon emission reduction, render the developed lightweight concrete mixture to be broadly used in dry concrete applications with different strength requirements that are mainly subjected to bending loads during serviceability.

Sirivivatnanon, V, Thomas, P, Joshua Tapas, M & Nhu Nguyen, T 2023, 'Reliability of AMBT and CPT in testing the effectiveness of SCM to mitigate alkali–silica reaction of field concrete', Construction and Building Materials, vol. 369, pp. 130510-130510.
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Stone, RC, Farhangi, V, Fatahi, B & Karakouzian, M 2023, 'A novel short pile foundation system bonded to highly cemented layers for settlement control', Canadian Geotechnical Journal, vol. 60, no. 9, pp. 1332-1351.
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While design methods of deep foundations are mainly developed for homogenous soil deposits, the presence of highly cemented layers could lead to underestimation of resistance and overestimation of settlement of pile foundations. This study presents a novel approach using competent caliche layers bonded to the top and bottom of a continuous flight auger (CFA) pile as a new composite foundation system named caliche stiffened pile (CSP). The key objective is to optimize the required pile length in a cost-effective approach without ameliorating soil properties. Settlements of the CSP foundation for a high-rise building were monitored and full-scale tests were conducted to measure piles’ capacity. Finite element back analyses were performed to avoid adverse effect of sample disturbance in settlement calculations. A back calculation of a test fill embankment was performed to determine soil stiffness parameters by simulating an unscheduled imposed load to the structure. Impacts of the CSP on controlling the settlement of pile foundation and optimizing the required pile length are investigated using finite element analysis and a parametric study. The proposed CSP foundation can reduce the CFA pile settlement significantly in the presence of caliche layers with thickness equal or greater than a pile diameter at CFA pile head and toe, where the CSP is located.

Stuart, B, Wong, S, Goodall, R, Beale, A, Chu, C, Nel, P, Amin-Jones, H & Thomas, P 2023, 'Safe Storage? An Assessment of Polyethylene for the Storage of Heritage Objects', Studies in Conservation, vol. 68, no. 6, pp. 669-678.
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Sealable polyethylene bags are widely used to protect and store heritage items. While polyethylene is regarded as a stable material, consideration should be given to potential chemical interactions between the polymer and stored objects. The presence of additives used in manufactured polyethylene storage materials should also be considered when they are used in contact with objects. For this study, infrared spectroscopy has been successfully used to identify storage materials and associated additives, as well as to characterise the chemical changes that they undergo. Three case studies are presented that demonstrate that polyethylene bags can undergo chemical changes when exposed to the typical storage conditions used for heritage objects. The storage of degrading cellulose nitrate items shows that polyethylene undergoes oxidation when exposed to the cellulose nitrate degradation products and is identified as detrimental to long term storage viability of the polyethylene. An investigation of the yellow discolouration of polyethylene bags suggests that the oxidation of antioxidant additives, rather than the polyethylene, is responsible for the colour change. It is also demonstrated that polyethylene bags used in a procedure for the consolidation of archaeological ceramics show an interaction between the adhesive solvent employed and the bag additives.

Talaei, S, Zhu, X, Li, J, Yu, Y & Chan, THT 2023, 'Transfer learning based bridge damage detection: Leveraging time-frequency features', Structures, vol. 57, pp. 105052-105052.
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Tao, G, Guo, E, Yuan, J, Chen, Q & Nimbalkar, S 2023, 'Permeability and Cracking of Compacted Clay Liner Improved by Nano-SiO2 and Sisal Fiber', KSCE Journal of Civil Engineering, vol. 27, no. 12, pp. 5109-5122.
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Tao, G, Ouyang, Q, Lei, D, Chen, Q, Nimbalkar, S, Bai, L & Zhu, Z 2023, 'Erratum for “NMR-Based Measurement of AWRC and Prediction of Shear Strength of Unsaturated Soils”', International Journal of Geomechanics, vol. 23, no. 9.
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Tao, G, Peng, P, Chen, Q, Nimbalkar, S, Huang, Z, Peng, Y & Zhao, W 2023, 'A new fractal model for nonlinear seepage of saturated clay considering the initial hydraulic gradient of microscopic seepage channels', Journal of Hydrology, vol. 625, pp. 130055-130055.
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Tao, M, Luo, H, Wu, C, Cao, W & Zhao, R 2023, 'Dynamic analysis of the different types of elliptic cylindrical inclusions subjected to plane SH‐wave scattering', Mathematical Methods in the Applied Sciences, vol. 46, no. 2, pp. 2773-2800.
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The complex boundary of the elliptical inclusion rendered it difficult to solve the problem of wave scattering. In this study, the steady‐state response was analyzed using the wave function expansion method. Subsequently, the Ricker wavelet was employed as the transient disturbance, and Fourier transform was used to determine the distribution of transient dynamic stress concentration around the elliptical inclusion. The effects of wave number, elliptical axial ratio, and difference in material properties on the distribution of the dynamic stress concentration around the elliptical inclusion were evaluated. The numerical results revealed that the dynamic stress concentration always appeared at both ends of the major axis and minor axis of the elliptical inclusion, and the difference in material properties between the inclusion and medium influenced the variations in the dynamic stress concentration factor with the wave number and elliptical axial ratio.

Tao, M, Xiang, G-L, Zhao, R & Wu, C-Q 2023, 'Scattering of P-wave and transient response around a fluid-filled cavity in an elastic medium', Journal of Central South University, vol. 30, no. 2, pp. 568-583.
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Tapas, MJ, Thomas, P, Vessalas, K, Nsiah-Baafi, E, Martin, L & Sirivivatnanon, V 2023, 'Comparative study of the efficacy of fly ash and reactive aggregate powders in mitigating alkali-silica reaction', Journal of Building Engineering, vol. 63, pp. 105571-105571.
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Wan, S, Liu, Y, Ding, G, Runeson, G & Er, M 2023, 'Risk allocation for energy performance contract from the perspective of incomplete contract: a study of commercial buildings in China', International Journal of Climate Change Strategies and Management, vol. 15, no. 4, pp. 457-478.
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PurposeThis article aims to establish a dynamic Energy Performance Contract (EPC) risk allocation model for commercial buildings based on the theory of Incomplete Contract. The purpose is to fill the policy vacuum and allow stakeholders to manage risks in energy conservation management by EPCs to better adapt to climate change in the building sector.Design/methodology/approachThe article chooses a qualitative research approach to depict the whole risk allocation picture of EPC projects and establish a dynamic EPC risk allocation model for commercial buildings in China. It starts with a comprehensive literature review on risks of EPCs. By modifying the theory of Incomplete Contract and adopting the so-called bow-tie model, a theoretical EPC risk allocation model is developed and verified by interview results. By discussing its application in the commercial building sector in China, an operational EPC three-stage risk allocation model is developed.FindingsThis study points out the contract incompleteness of the risk allocation for EPC projects and offered an operational method to guide practice. The reasonable risk allocation between building owners and Energy Service Companies can realize their bilateral targets on commercial building energy-saving benefits, which makes EPC more attractive for energy conservation.Originality/valueExisting research focused mainly on static risk allocation. Less research was directed to the phased and dynamic risk allocation. This study developed a theoretical three-stage EPC risk allocation model, which provided the theoretical support for dyn...

Wang, LJ, Wu, CQ, Fan, LF & Wang, M 2023, 'Investigation of wave reflection at the joint with different wave impedances on two sides', Waves in Random and Complex Media, vol. 33, no. 2, pp. 237-253.
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When the stress wave propagates through rock mass with different wave impedances on two sides. It shows different reflection tendencies compared with the traditional study of wave propagation. A characteristic line method combined with the displacement discontinuity model was proposed to study the wave reflection through such rock mass. The effects of incident frequency, joint stiffness and wave impedance ratio on the reflection coefficient were discussed. The results show that the reflection coefficient increases as the wave impedance ratio increases. The traditional study of wave reflection can be regarded as a special case of the present study when the wave impedance ratio equals 1.0. Moreover, the difference of reflection coefficients decreases as the incident frequency increases, while increases as the joint stiffness and wave impedance ratio increase when the wave impedance ratio is larger than 1.0. When the wave impedance ratio is smaller than 1.0, the difference of reflection coefficients increases firstly and then decreases with the increase of incident frequency and joint stiffness, while decreases as the wave impedance ratio increases. For the cases of large incident frequency or small joint stiffness, the effects of wave impedance ratio can be neglected for the approximated prediction of wave reflection.

Wang, X, Li, W, Huang, Y, Zhang, S & Wang, K 2023, 'Study on shape-stabilised paraffin-ceramsite composites with stable strength as phase change material (PCM) for energy storage', Construction and Building Materials, vol. 388, pp. 131678-131678.
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Wei, J, Li, J & Wu, C 2023, 'Study on hybrid fibre reinforced UHPC beams under single and repeated lateral impact loading', Construction and Building Materials, vol. 368, pp. 130403-130403.
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This paper investigates the dynamic response of hybrid fibre reinforced ultra-high performance concrete (UHPC) beams against single and repeated low-velocity impact loads. A brief description of the drop weight impact tests on the UHPC beams was presented first followed by the development of the material and structural model in finite element analysis. A plasticity-based concrete material model with validated compressive and tensile strength surface and damage algorithm was adopted for hybrid fibre reinforced UHPC material. Based on the test results, the bond-slip behaviour between steel rebar and UHPC matrix was developed in an empirical form and incorporated in the model. Compared to the model with the bond-slip definition, the model with perfect bonding was found to underestimate the maximum mid-span deflection, which highlighted the necessity of considering the bond-slip behaviour in dynamic analysis where large deflection occurs. The repeated impact tests were performed numerically, and the results were validated with experimental data. A parametric study was then performed to investigate the effect of key parameters, including different impact energy and the same impact energy but different impact numbers. The results indicated when the total energy increased, the repeated impact loads became more hazardous than the single impact load. With the validated model, the dynamic shear force and bending moment distribution diagrams were compared to study the failure mechanism in single and repeated impact loads.

Wei, J, Li, J, Liu, Z, Wu, C & Liu, J 2023, 'Behaviour of hybrid polypropylene and steel fibre reinforced ultra-high performance concrete beams against single and repeated impact loading', Structures, vol. 55, pp. 324-337.
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Wei, J, Li, J, Wu, C, Hao, H & Liu, J 2023, 'Experimental and numerical study on the impact resistance of ultra-high performance concrete strengthened RC beams', Engineering Structures, vol. 277, pp. 115474-115474.
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To enhance the impact resistance of built reinforced concrete (RC) members, the effectiveness of using ultra-high performance concrete (UHPC) for strengthening RC structures was investigated in this study. The mechanical properties of UHPC were evaluated by the uniaxial compression, tension and flexural bending tests. Drop weights with hemispherical and wedge-shaped indenter were adopted to impact the beam specimens with and without UHPC strengthening. A total of six beams, including three control RC beams and three UHPC jacketed RC (RC-UHPC) beams, were tested. The beams were prestressed in the axial direction with a 200 kN force. The test results revealed that the UHPC jackets improved the structural impact resistance. With an impact mass of 411 kg and an impact velocity of 4.95 m/s, the maximum and residual deflection of the RC-UHPC specimen decreased by 15.3 % and 21.1 % as compared to the RC control specimen, and the failure mode shifted from diagonal shear failure to flexural failure. To further investigate the dynamic responses of the beams, a detailed finite element model was established and validated with the test results in terms of the impact force, structural deflection and damage profile. The dynamic shear force and bending moment distribution diagrams were numerically derived to examine the failure mechanism of the test specimens. Finally, a parametric study was conducted to evaluate the effect of different impact locations and UHPC jacket length on the impact resistance of strengthened RC beams.

Xiang, G, Tao, M, Zhao, R, Zhao, H, Wu, C & Memon, MB 2023, 'Dynamic characteristics of rockbolt anchorage structure under radial cylindrical P wave', Soil Dynamics and Earthquake Engineering, vol. 174, pp. 108176-108176.
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Xu, T, Li, Y & Leng, D 2023, 'Mitigating jacket offshore platform vibration under earthquake and ocean waves utilizing tuned inerter damper', Bulletin of Earthquake Engineering, vol. 21, no. 3, pp. 1627-1650.
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AbstractThe unwanted vibrations of offshore structures induced by wave or earthquake loads can lead to the reduction of the service life and fatigue failure of the offshore platforms. This paper introduces tuned inerter damper (TID) to a jacket offshore platform as passive control device for mitigating the excessive vibrations of platform structure induced by wave and earthquake loads. An analytical design method is proposed for jacket platforms and the influence of installation location on the modal response is investigated. The proposed design method can determine the optimal installation position and obtain the optimal design parameters by transform the original multi-degree of freedom (MDOF) system to a single DOF (SDOF) modal system. Two sets of closed-form solutions of which corresponding to wave and earthquake excitations are derived based on the $${\mathrm{H}}_{2}$$ H 2 optimization criterion. Further, a practical 90 (m) high and 80 (m) deep in-water jacket offshore platform is used in numerical simulation and the wave forces are modeled using Morison’s equation. The case study finds that the optimal installation location of TID is deck level for both wave and earthquake loads. The proposed design method is validated by the numerical example and the results demonstrate that TID system can effectively mitigate the maximum, minimum, and RMS responses of jacket platforms. Besides, the TID is more effective when the jacket platform is under the action of waves and the tuning of TID according to earthquake load is more reliable when the jacket platform subjected to both wave and seismic loads.

Xu, T, Li, Y, Lai, T & Li, S 2023, 'H2 and H∞ optimal designs of tuned inerter dampers for base motion excited structures with inherent damping', Journal of Vibration and Control, vol. 29, no. 15-16, pp. 3692-3707.
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Tuned inerter damper (TID) has recently gained increasing attention as a new structural control mechanism for seismic protection of structures. Currently, theoretical investigations are undertaken by researchers to reveal its fundamentals and to understand its underline principles in altering the structural performances of structures against dynamic loadings. However, the comprehensive study of optimization design of TID for undamped structures is lacking and the majority of the research focuses on the optimization of TID for structures without any damping. This research evaluates the [Formula: see text] and [Formula: see text] optimal designs of TIDs on the structures with damping. Using SDOF structure as an example, the frequency response function of the system equipped with TID underground motion excitation is obtained. The [Formula: see text] and [Formula: see text] designs of TID for structures without damping are derived considering various response parameters using analytical method. A numerical search method is utilized for the [Formula: see text] and [Formula: see text] designs of TID for structures with damping; meanwhile, a set of explicit formulae are obtained by curve-fitting for convenience in the application. Finally, the relative motion response of the inerter is explored, and an optimal design formula of TID which can reduce the displacements of primary mass and inerter simultaneously, is proposed.

Xu, Z, Khabbaz, H, Fatahi, B & Wu, D 2023, 'Double-layered granular soil modulus extraction for intelligent compaction using extended support vector machine learning considering soil-structure interaction', Engineering Structures, vol. 274, pp. 115180-115180.
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Intelligent Compaction (IC) has been acquiring a growing interest in real-time quality control of compacted soil layers because of its high efficiency and full-area coverage. The current intelligent compaction technology allows the determination of the uniformity level of compaction over large areas according to the dynamic response of the roller. However, accurate real-time determination of the soil modulus during compaction based on roller acceleration has been challenging due to the multi-layered composite nature of the soil and the nonlinearities of the governing dynamic equations of motion and soil response. This study adopts a double-layered soil profile, and a three-dimensional finite element model, accounting for soil-drum interaction, is utilised for the analysis. The isotropic hardening elastoplastic hysteretic model was implemented to simulate the soil behaviour subjected to cyclic loading ranging from small to large strain amplitudes and account for stiffness degradation. The comprehensive dataset composed of the roller acceleration response and ground characteristics is then used to correlate the predicted soil modulus via an advanced machine learning approach. The adopted machine learning method incorporating Gaussian Kernel and Generalised Gegenbauer Kernel functions can reasonably predict the double-layered soil modulus during roller compaction. Additional analyses were conducted to observe the proper training size and number of iterations to achieve real-time quality control to be used by site engineers. Furthermore, the influences of the relative modulus ratio, drum length and top layer modulus on the soil surface dynamic displacement are discussed.

Xu, Z, Li, J & Wu, C 2023, 'A numerical study of blast resistance of fire damaged ultra-high performance concrete columns', Engineering Structures, vol. 279, pp. 115613-115613.
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Concrete structures may experience fire and blast during their service life as a result of accidental explosions or vehicular collisions. Both fire and blast can cause severe damage that threatens the structural safety. In the present study, reinforced concrete columns fabricated by ultra-high performance concrete (UHPC) are investigated under coupled fire and blast loads. Strength degradation and damage of UHPC and steel reinforcement after exposure to elevated temperature (up to 800 °C) were established based on the experimental data. In addition to the detrimental effect on individual material, bond-slip behaviour between the UHPC and reinforcement affected by the elevated temperature was considered. The findings revealed that material strength degradation and damage owing to elevated temperature significantly influenced the structural blast resistance, and the degraded bond-slip behaviour had varying impact on the structural response depending on the structural damage mode. Up to 10% mid-span displacement differences were noted in columns with/without the consideration of bond-slip behaviour. Different failure mechanisms pre- and post-fire damage were observed in the numerical simulations. To quickly assess blast induced damage on UHPC columns, Pressure-Impulse (P-I) diagrams of the UHPC columns before and after elevated temperature were established and empirical formulae were proposed to generate the P-I diagrams.

Yang, Y, Wu, C & Liu, Z 2023, 'Rate dependent behaviour of 3D printed ultra-high performance fibre-reinforced concrete under dynamic splitting tensile', Composite Structures, vol. 309, pp. 116727-116727.
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Yang, Y, Xu, S & Wu, C 2023, 'Roles of carbon black or carbon fibre on improving mechanical and electromagnetic properties of ultra-high performance concrete in K-band frequency range', Journal of Sustainable Cement-Based Materials, vol. 12, no. 7, pp. 856-870.
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Yu, Y, Li, J, Li, J, Xia, Y, Ding, Z & Samali, B 2023, 'Automated damage diagnosis of concrete jack arch beam using optimized deep stacked autoencoders and multi-sensor fusion', Developments in the Built Environment, vol. 14, pp. 100128-100128.
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A novel hybrid framework of optimized deep learning models combined with multi-sensor fusion is developed for condition diagnosis of concrete arch beam. The vibration responses of structure are first processed by principal component analysis for dimensionality reduction and noise elimination. Then, the deep network based on stacked autoencoders (SAE) is established at each sensor for initial condition diagnosis, where extracted principal components and corresponding condition categories are inputs and output, respectively. To enhance diagnostic accuracy of proposed deep SAE, an enhanced whale optimization algorithm is proposed to optimize network meta-parameters. Eventually, Dempster-Shafer fusion algorithm is employed to combine initial diagnosis results from each sensor to make a final diagnosis. A miniature structural component of Sydney Harbour Bridge with artificial multiple progressive damages is tested in laboratory. The results demonstrate that the proposed method can detect structural damage accurately, even under the condition of limited sensors and high levels of uncertainties.

Yuan, P, Xu, S, Liu, J, Su, Y & Wu, C 2023, 'Experimental and numerical study of blast resistance of geopolymer based high performance concrete sandwich walls incorporated with metallic tube core', Engineering Structures, vol. 278, pp. 115505-115505.
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Zhang, Z-J, Liu, Z-X, Zhang, H, Meng, S-B, Shi, J-H, Zhao, J-W & Wu, C-Q 2023, 'Spatial distribution and machine learning-based prediction model of natural gas explosion loads in a utility tunnel', Tunnelling and Underground Space Technology, vol. 140, pp. 105272-105272.
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Zhao, H, Li, W, Gan, Y, Wang, K & Luo, Z 2023, 'Nano/microcharacterization and image analysis on bonding behaviour of ITZs in recycled concrete enhanced with waste glass powder', Construction and Building Materials, vol. 392, pp. 131904-131904.
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Zhao, Y, Tao, M, Du, K, Wu, Y & Wu, C 2023, 'Development and application of gas adsorption model for coal based on particle flow code', Gas Science and Engineering, vol. 110, pp. 204858-204858.
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Zheng, J, Hang, T, Sun, Z, Jiang, S, Li, Z, Dong, W, Li, X, Li, Y, Sun, A & Chen, Y 2023, 'Temperature-stimulated composite foams for reversibly switching microwave absorption towards electromagnetic interference shielding capability', Diamond and Related Materials, vol. 140, no. Part B, pp. 110499-110499.
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Zhou, S, Lu, Y, Pan, Y, Li, J, Qu, F, Luo, Z & Li, W 2023, 'Flowability prediction of recycled α-hemihydrate gypsum for 3D powder printing under combined effects of different glidants using response surface methodology', Developments in the Built Environment, vol. 16, pp. 100265-100265.
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Boyd-Weetman, B, Thomas, P, De Silva, P & Sirivivatnanon, V 1970, 'Comparison of accelerated test methods for ASR reactivity testing', https://ciaconference.com.au/concrete2023/content.html, Conference of the Concrete Institute of Australia, Concrete 2023, Resilient and Sustainable Structures: Breaking Down Barriers, Perth, WA.
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The deleterious alkali silica reaction (ASR) affects the long term durability of concrete by reducing service life. Standardised accelerated test methods are used to rapidly asses reactivity. Rapidly accelerating the ASR reaction process may produce reactivity responses from aggregates that would not occur in field conditions. The environment in which the accelerated test is conducted is crucial in determining the degree to which the ASR reaction and associated deleterious expansion proceeds. In this study, a course reactive Australian aggregate concrete is exposed to standardised, and modified test methods to assess their effect on the observed ASR reaction. Australia has produced AS1141.60.2, a standardised concrete prism test at 38ºC for determining ASR reactivity of aggregates which is deployed in this study alongside a 60ºC concrete prism test and prism immersion test methods. This paper compares deleterious ASR expansion across a number of accelerated test methods and found good correlation between CPT and immersion based test methods.

CHEN, D, Wu, C & Li, J 1970, 'Comparative Analysis of Modeling Methods for Hydrogen-Air Detonation', The 11th International Symposium on Impact Engineering, Perth, Australia.

Cowled, C, Slattery, T, Crews, K & Brooke, H 1970, 'INFLUENCE OF PLASTERBOARD ON THE STRUCTURAL PERFORMANCE OF TIMBER-FRAMED SHEAR WALLS', World Conference on Timber Engineering (WCTE 2023), World Conference on Timber Engineering 2023 (WCTE2023), World Conference on Timber Engineering (WCTE 2023), pp. 3417-3422.
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Timber-framed shear walls are commonly used in residential buildings to provide lateral strength and stiffness against wind and earthquake loads. Wood-based panel products, such as plywood and oriented strand board, are typically fixed to timber framing with nails or screws to provide the necessary racking resistance of a shear wall. Plasterboard is a panel product used on walls to achieve a smooth finished surface. Plasterboard provides some strength and stiffness to the wall even though its primary function is architectural; however, most shear wall tests ignore the influence of plasterboard. The aim of this study is to quantify the influence of plasterboard on the structural performance of timber-framed shear walls. To achieve this aim, six (6) timber-framed shear walls (groups P1 and P2) were fabricated with 7mm F8 plywood sheathing on one side and 10mm plasterboard on the other side and tested under a monotonic loading protocol. Results were then compared with previous test results of three (3) similar timber-framed shear walls (group M1) without plasterboard. Results show that plasterboard improved the ultimate racking strength of these shear walls by up to 53%, a statistically significant result. Shear wall stiffness and failure modes were not affected by adding plasterboard.

Davies, J, Thai, MT, Hoang, TT, Nguyen, CC, Phan, PT, Zhu, K, Nhi Tran, DB, Ho, VA, La, HM, Ha, QP, Lovell, NH & Do, TN 1970, 'A Flexible 3D Force Sensor with In-Situ Tunable Sensitivity', 2023 IEEE International Conference on Robotics and Automation (ICRA), 2023 IEEE International Conference on Robotics and Automation (ICRA), IEEE.
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Dong, W, Li, W, Liebscher, M & Mechtcherine, V 1970, 'Development of Self-sensing Cementitious Composites with Improved Water and Chloride Resistance', RILEM Bookseries, Springer Nature Switzerland, pp. 499-508.
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The piezoresistivity of cement-based sensors subjected to moisture ambient is changeable due to the porous structures and pore solutions inside of cementitious composites. This study explored the electrical resistivity and self-sensing performance of carbon black (CB) filled cement-based sensors mixed with silicone hydrophobic powder (SHP) and crystalline waterproofing admixture (CWA), especially before and after different durations of immersion in freshwater and 3% sodium chloride solution. The results show that the composites with SHP exhibited the best water impermeability, while the counterpart containing CWA presented the optimal chloride resistance. The piezoresistivity increased in sodium chloride solution because of the increased free ions. The outcomes are expected to illuminate the piezoresistive behavior of hydrophobic cement-based sensors subjected to moisture and chloride environments, thereby promoting structural health monitoring applications in the future.

Lyv, P, Leng, D, Li, Y, Xu, T, Huixing, W & Xu, H 1970, 'Semi-active magnetorheological suspension of a full-vehicle model based on combined vertical and attitude control', 2023 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM), 2023 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM), IEEE.
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Malek, S, Cheraghi-Shirazi, N, Crews, K, Parra, R, Creagh, A & Khoshkbari, P 1970, 'A COMPARATIVE STUDY OF DESIGN STANDARDS FOR ASSESSMENT OF LONG-SPAN STEEL-TIMBER COMPOSITE FLOORS UNDER HUMAN-INDUCED VIBRATION', World Conference on Timber Engineering (WCTE 2023), World Conference on Timber Engineering 2023 (WCTE2023), World Conference on Timber Engineering (WCTE 2023), pp. 1936-1942.
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Steel-timber composite (STC) floors are gaining popularity for residential and commercial buildings worldwide. Adding steel joists to wood-based panels is an attractive option for some designers to increase the span of timber floors. However, there is often a serviceability (vibration) concern with timber composite floors. It is well-known from the literature that human comfort due to vibration is subjective, and people's perception of comfort vanes. Nevertheless, structural engineers still need to consider vibration in designing composite timber floors according to various standards and guidelines, especially when comparing two alternative designs. This study investigates the vibration behavior of STC floors under footfall force using a numerical model validated by experimental data. Transient finite element (FE) analysis is conducted to simulate human walking on the floor. The study also discusses acceptability of STC floors according to guidelines and building codes (e.g., AISC Design Guide 11, ATC, CLT Handbook, Eurocode 5). Lastly, the effects of vanous design parameters, such as CLT thickness, damping ratio, and CLT-to-CLT connection, on the vibration behavior of the composite timber floor are assessed.

Martin, L, Thomas, P, De Silva, P & Sirivivatnanon, V 1970, 'Durability Loss in Concrete Due to ASR-DEF, The Role of Aggregate Reactivity in Deleterious Delayed Ettringite Formation', Concrete 2023 Resilient and Sustainable Concrete: Breaking Down Barriers, Concrete Institute of Australia Biennial National Conference, Perth.
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Durability of concrete and cementitious materials is important to their worldwide usage in housing and infrastructure. Two known causes of durability loss in concrete are the alkali-silica reaction (ASR) and delayed ettringite formation (DEF), which are chemical processes with the potential for expansion, cracking, and strength loss in affected elements. There is significant overlap in the contributing factors for ASR and DEF, in particular pore solution alkalinity. DEF is of most concern for large, precast concrete structures, although in Australia reported cases of deleterious DEF have been in conjunction with mild or moderate ASR. Current guidelines regarding DEF are based on laboratory experiments in mortar specimens, and the role of the aggregate and ASR in concrete has been overlooked. Mitigation strategies for DEF involve temperature thresholds during curing, chemical limits for the binder, and the use of supplementary cementitious materials (SCMs) in the mix design. This study investigates the role of aggregate reactivity, curing temperature, and cement composition in the susceptibility of concrete elements to deleterious DEF, and the efficacy of fly-ash as an SCM in preventing deleterious ASR-DEF. Concrete specimens containing ASR-reactive aggregates were made with different binder and curing conditions, then monitored for expansion and strength loss over two years. Contributions towards the understanding of ASR-DEF mechanisms and the development of industry risk assessments in Australia are presented in this paper.

Martin, L, Thomas, P, De Silva, P & Sirivivatnanon, V 1970, 'Role of Aggregate Reactivity, Binder Composition, and Curing Temperature on the Delayed Ettringite Formation and Associated Durability Loss in Concrete', Springer Nature Singapore, pp. 83-91.
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AbstractThe durability of concrete is critical to its worldwide use as a structural material for buildings and infrastructure, with the lifetime service of concrete greatly affecting its economic, environmental, and social costs. Causes of durability loss in some concrete structures can be attributed to the alkali–silica reaction (ASR) and delayed ettringite formation (DEF). Both are chemical reactions that have the potential to cause expansion and strength loss in affected elements. Significant overlap exists in the factors contributing to ASR and DEF in concrete structures, with widely reported evidence of deleterious DEF frequently occurring in conjunction with mild or moderate ASR. For precast concrete, experiments in mortars have provided limits in the alkali and sulfate content of the binder and maximum curing temperatures used to minimize DEF risk. The role of other constituents in concrete specimens, notably the aggregate, has been overlooked. We investigated the role of reactive aggregates and ASR in the susceptibility of concrete to deleterious DEF.

Nguyen, HAD, Le, TH, Ha, QP & Azzi, M 1970, 'Deep learning for construction emission monitoring with low-cost sensor network', Proceedings of the 40th International Symposium on Automation and Robotics in Construction, 40th International Symposium on Automation and Robotics in Construction, International Association for Automation and Robotics in Construction (IAARC).
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Nguyen, LV, Le, TH & Ha, QP 1970, 'Prototypical digital twin of multi-rotor UAV control and trajectory following', Proceedings of the 40th International Symposium on Automation and Robotics in Construction, 40th International Symposium on Automation and Robotics in Construction, International Association for Automation and Robotics in Construction (IAARC).
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Nguyen, QD, De Carvalho Gomes, S, Alnahhal, MF, Li, W, Kim, T & Castel, A 1970, 'Testing Geopolymer Concrete Performance in Chloride Environment', RILEM Bookseries, Springer Nature Switzerland, pp. 1197-1203.
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The major barriers to geopolymer concrete widespread adoption by the construction industry are concerns about durability and exclusion from current standards. Chemical reactions characterizing alkali-activated binder systems differ drastically from conventional hydration process of Portland cement. Thus, the mechanisms by which concrete achieves potential durability are different between the two types of binders. As a result, testing methods and performance-based requirements for geopolymer must be developed to be incorporated in a performance base standard. The standard ASTM C1202 RCPT fails to measure the charges passed through most of geopolymer concretes. A modified version of RCPT using 10V (as opposed to 60V specified by standard ASTM C1202) is considered, allowing to successfully complete the tests for all geopolymer concretes. Various precursors are investigated including fly ash, GGBFS, calcined clay and ferronickel slag. Different activators are also considered. A good correlation is observed between modified ASTM C1202 and Standard ASTM C1556 bulk diffusion test results. Performance-based specifications are proposed.

Nguyen, TN, Li, J, Sirivivatnanon, V & Sanchez, L 1970, 'Modeling the Alkali–Silica Reaction and Its Impact on the Load-Carrying Capacity of Reinforced Concrete Beams', Nanotechnology in Construction for Circular Economy, Springer Nature Singapore, pp. 365-372.
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AbstractThe alkali–silica reaction (ASR) is one of the most harmful distress mechanisms affecting concrete infrastructure worldwide. The reaction leads to cracking, loss of material integrity, and consequently compromises the serviceability and capacity of the affected structures. In this study, a modeling approach was proposed to simulate ASR-induced expansion considering three-dimensional stress/restraint conditions, and its impact on the structural capacity of reinforced concrete members. Both the losses in concrete mechanical properties and prestressing effects induced by the expansion under restraints are taken into account in the model. Validation of the developed model is conducted using reliable experimental datasets derived from different laboratory testings and field exposed sites. With the capability of modelling both ASR-induced expansion and its impact on structural capacity, the model provides valuable results to specify effective repair and/or mitigation strategies for concrete structures affected by ASR.

Tapas, MJ, Thomas, P & Sirivivatnanon, V 1970, 'Effect of supplementary cementitious materials on carbonation rate and CO2 uptake', https://ciaconference.com.au/concrete2023/content.html, Conference of the Concrete Institute of Australia, Concrete 2023, Resilient and Sustainable Structures: Breaking Down Barriers, Perth, WA.
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Carbonation, which pertains to the reaction of carbon dioxide (CO2) with the calcium-bearing phases of the binder, is a natural process that leads to the modification of the pore solution, microstructure as well as various properties of the concrete. This process, although traditionally perceived as undesirable due to its role in increasing the susceptibility of the concrete steel reinforcement to corrosion, is gaining global interest as a possible means to reduce the carbon footprint of the construction industry. CO2 sequestration in concrete is perceived to play a key role in improving the sustainability of concrete production. The carbonation process however remains not fully understood, particularly in binder systems with supplementary cementitious materials. This paper discusses the chemistry of carbonation, the change in phases due to carbonation and the influence of binder type on the carbonation rate and CO2 uptake.

Tapas, MJ, Vessalas, K, Thomas, P, Gowripalan, N & Sirivivatnanon, V 1970, 'Composition of Alkali–Silica Reaction Products in Laboratory and Field Concrete', Springer Nature Singapore, pp. 27-36.
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AbstractThis study investigated the composition of alkali–silica reaction (ASR) products formed in mortar and concrete that underwent accelerated ASR testing using two test methods: the accelerated mortar bar test (AMBT) and the simulated pore solution immersion test (SPSM). The composition of the ASR products formed in the accelerated tests was compared with those in a 25-year old bridge in New South Wales demolished due to ASR. Results showed that the ASR products inside an aggregate contained calcium (≈20%), silicon (≈60%), and alkalis (≈20%) regardless of the ASR test method used. The ASR products in the AMBT sample only contained sodium, whereas the ASR products in the SPSM test and the demolished bridge both contained significant amounts of sodium and potassium, which indicated that the type of alkali in the ASR product is largely affected by the dominant alkali in the pore solution. However, considering that the total alkali content (Na + K) in the ASR products was similar regardless of the ASR test method used, this suggests that the total alkali content has more influence on the rate of expansion than the type of alkali. The composition of the ASR products also notably varied depending on the location in the concrete. ASR products closer to the cement paste had a higher calcium and lower alkali content than those inside an aggregate, which suggests that the calcium as well as the alkali content of the ASR products plays a significant role in the degree of ASR expansion.

Xu, T, Wang, H, Li, Y, Leng, D & Xu, H 1970, 'Full Vehicle Experimental Testing of Semi-active Suspension Equipped with Magnetorheological Dampers', 2023 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM), 2023 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM), IEEE.
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Zhang, X, Zhu, X, Yu, Y & Li, J 1970, 'Unsupervised Knowledge Transfer for Structural Damage Detection with Limited Data', The twelfth International Conference on Structural Health Monitoring of Intelligent Infrastructure, Hangzhou, China.