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Bonding behavior between FRP and Steel fibre reinforced concrete is not well studied. This study experimentally investigates the interfacial bond behavior between basalt fibre reinforced polymer sheet (BFRP) and steel fibre reinforced concrete (SFRC). Short steel fibres with four volume fractions were used to investigate the interfacial bond behavior of BFRP-SFRC as the mechanical properties of the concrete substrate (i.e. compressive strength and tensile strength) can be improved by adding steel fibres. The effects of volume fraction on the bond strength, effective bond length, local slip at the peak shear stress, and interfacial bond-slip relationship are evaluated and discussed. The experimental results showed that the debonding process becomes more ductile as the debonding plateau in the load and displacement curves has been significantly extended. Findings from the present tests show that the specimens with steel fibres of 0.25%, 0.50% and 1.0% experienced significant increase in the peak interfacial shear stress up to 31%, 53%, and 76% over the control specimen without steel fibres, respectively. In addition, the analytical bond strength models and interfacial bond-slip models, incorporating the effect of short steel fibres, are proposed.

In this study, new types of folded structures with different base shapes (i.e. triangle, square and pentagon) are proposed. Each structure is folded from a thin sheet of aluminium, with the geometry of open-top truncated pyramid and connected inclination sidewalls. The purpose of this unique geometry is to increase the crushing resistance of the folded structure while maintaining a uniform collapsing behaviour under different crushing rates as compared with other existing folded kirigami structures. Three base shapes, i.e. triangle, square and pentagon, are considered in this study. Geometric parameters are derived for these structures based on three governing parameters: top and bottom edge length and cell height. Numerical models of these structures are firstly calibrated with quasi-static crushing test data followed by dynamic crushing simulations. To evaluate the crushing performances, structural responses including peak and average crushing stress, uniformity ratio and densification strain are compared among these three structures and also with the widely studied Miura-origami structure of the same density. Superior performances of crushing are observed for the proposed open-top truncated pyramid structure with higher average stress and more uniform collapsing under various loading rates, indicating potential application as energy absorber.

This study experimentally investigates the static and impact response of a new single phase syntactic foam which has been newly developed for impact energy absorption. The syntactic foam had different densities ranging from 172 kg/m3 to 366 kg/m3 depending on the thickness and composition of the coating layers. The impact response and impact energy absorption were investigated by using instrumented drop-weight impact tests. Under static loads, the mechanical properties of the syntactic foam including the compressive strength, the yield stress, and Young's modulus increased with the density but the rate of increment decreased at higher densities. There were two types of progressive failures of the syntactic foam under impact loads. The failure propagation was examined and found to be dependent on the material density and the impact velocity. Interestingly, the densification only occurred in the low-density specimens while this phenomenon was not observed for the specimens with the density greater than 288 kg/m3. The impact energy absorption capacity increased significantly with the density and the wall thickness of the macrospheres.

Structural response of the sacrificial cladding with square dome-shape kirigami (SDK) structure as core under blast loads is investigated in this study. A sample of SDK core folded from a pre-cut aluminium sheet is crushed under quasi-static loading condition. A numerical model is then developed and calibrated using experimental data. The calibrated model of SDK foldcore cladding is then placed on to a rigid block as a sacrificial layer to resist blast loading for structure protection. To evaluate the blast mitigation capacities, the parameters such as peak load transmitted to the protected structure, energy absorption, centre crushed distance and loading duration are compared among the claddings with different cores. Compared to square honeycomb, superior performance of blast mitigation is demonstrated for the proposed SDK foldcore sacrificial cladding by yielding a uniform collapsing similar to aluminium foam. Significant increase in energy absorption of the core is observed for the sacrificial cladding with SDK foldcore. It also yields a higher plateau stress than aluminium foam of the same density and is applicable to a wider range of blast loadings. The peak transmitted load to the protected structure is reduced by more than 70% comparing with the case without cladding. SDOF analysis of the sacrificial cladding systems is carried out and validated using numerical results. Based on the SDOF analysis, complete solution is derived and then used to obtain simplified design charts to show the suitable range of blast load scenarios where the sacrificial claddings are effective.

With the increasing popularity of high-speed railway, more and more bridges are being constructed in Western China where debris flows are very common. A debris flow with moderate intensity may endanger a high-speed train traveling on a bridge, since its direct impact leads to adverse dynamic responses of the bridge and the track structure. In order to address this issue, a dynamic analysis model is established for studying vibrations of coupled train–track–bridge system subjected to debris flow impact, in which a model of debris flow impact load in time domain is proposed and applied on bridge piers as external excitation. In addition, a six-span simply supported box girder bridge is considered as a case study. The dynamic responses of the bridge and the running safety indices such as derailment factor, offload factor, and lateral wheel–rail force of the train are investigated. Some influencing factors are then discussed based on parametric studies. The results show that both bridge responses and running safety indices are greatly amplified due to debris flow impact loads as compared with that without debris flow impact. With respect to the debris flow impact load, the boulder collision has a more negative impact on the dynamic responses of the bridge and train than the dynamic slurry pressure. Both the debris flow impact intensity and train speed determine the running safety indices, and the debris flow occurrence time should be also carefully considered to investigate the worst scenario.

A new form of bi-directional Load-Self-Cancelling (LSC) sandwich panel is proposed in this paper. An array of square dome shaped steel sheet as core of the proposed sandwich panel is designed to cancel a certain amount of load during blast event owing to its arching geometry. The blast resistance and energy absorption capabilities of the sandwich panel are investigated numerically by using finite element analysis software LS-DYNA. The peak deflection of centre point on back face sheet, internal energy and peak boundary reaction forces are compared among monolithic plate, multi-arch uni-directional LSC structure, sphere dome structure and the proposed bi-directional LSC square dome sandwich panel. It is found that using the proposed bi-directional LSC square dome leads to 69%, 48% and 56% reduction in the out-of-plane boundary reaction force as compared to the flat plate, multi-arch panel and grid sphere panel, respectively. In addition, parametric studies of the influences of dome number, height, and layer material on the performances of the proposed bi-directional LSC sandwich panel subjected blast loads of different intensities are carried out to investigate the panel configuration on the effectiveness of its blast resistance and load-self-cancelling capability. The results demonstrate the superiority of the sandwich panel with the proposed bi-directional LSC core.

In this study, a new type of aluminium sandwich structure with folded square dome as core is proposed. The square dome tessellated core is folded using a single piece of aluminium sheet. Four types of folded dome structures with different base sizes and top face configurations, i.e. 10 mm closed top dome, 20 mm closed top dome, 10 mm open top dome, 20 mm open top dome are studied. A single cube strip model is numerically simulated and calibrated with the experimental results from the previous studies. Good agreement on the peak and average stress between numerical results and test data is achieved. The calibrated model is then used to simulate structural response of the proposed folded dome shape structures. The damage modes and the structural responses including average and peak stress, energy absorption, uniformity ratio and densification strain are compared among these folded structures. The proposed square dome kirigami foldcore shows good energy absorption characteristics under quasi-static loading and dynamic loading by yielding a large densification strain, a low initial peak stress and a small ratio of average stress to peak stress. In addition, unlike the existing cube strip structures, the proposed folded square dome structure shows insensitivity to the crushing speed in terms of initial peak stress and uniformity ratio. Compared with the existing tessellated kirigami foldcore of cube strip, the proposed folded square dome demonstrates a superior performance than most of Miura folded structures.

Syntactic foam is a lightweight and strong material which can be used in marine and aeronautical applications. However, the brittleness of the material limits its application to a broader range. Adding crumb rubber to the syntactic foam can increase its energy absorption capacity. The effect of crumb rubber on the fracture toughness and energy absorption capacity of 2-phase and 3-phase syntactic foam is evaluated under both static and impact loads. The experimental results have shown that the fracture toughness of the 2-phase rubberized syntactic foam increased by 8% while an increase of 22% of its fracture energy was observed. Under quasi-static loads, the 3-phase rubberized syntactic foam showed decreases in the compressive strength and elastic modulus but an increase in the energy absorption capacity as compared to the syntactic foam without crumb rubber. In addition, the impact energy absorption of the 3-phase rubberized syntactic foam increased by 24% as compared to that of the 3-phase syntactic foam without crumb rubber.

Roller compacted concrete (RCC) has been widely used in large scale constructions such as hydraulic structures and pavement. Because of the construction process, it has some unique material properties as compared to the ready-mix concrete. Structures made of RCC might be subjected to dynamic loads during its service life. Understanding the dynamic material properties of RCC is essential for better analysis and design of RCC structures. The study on dynamic compressive mechanical properties of RCC is very limited in literature. In this study, dynamic compressive properties of RCC under the strain rate up to 80/s are investigated by using Split Hopkinson Pressure Bar (SHPB). In addition, to investigate the size effects on dynamic impact tests, three sizes of cylindrical RCC specimens with the diameters of 50 mm, 75 mm and 100 mm are prepared and tested. The failure processes and the failure modes of RCC specimens with different dimensions under different strain rates, as well as the stress–strain curves under different strain rates and the energy absorption capacities of the tested specimens are compared. The influences of the specimen size, aggregates grading, and the existence of bedding surface in RCC on its dynamic properties are investigated. Based on the testing results, empirical formulae of DIF (dynamic increase factor) for the RCC compressive strength are proposed to predict the enhancement of material strength at different strain rates.

Prefabrication by off-site manufacturing leads to a reduced overall construction schedule, improved quality, and reduced resource wastage. Modular building is therefore increasingly popular and promoted. With the recent promotion a number of relevant studies have been completed, however, a review of the design, construction, and performance of modular buildings under different loading conditions is lacking. This paper presents a state-of-the-art review of modular building structures. First, structural forms and construction materials are presented as a brief introduction to the modular structures. Modular building is shown to refer not to a single structure type, but a variety of structural systems and materials. These modular structures might perform differently to similar traditional structures and the structural performance is highly dependent on inter- and intra-module connections. The structural response of modules to different hazards is then considered, followed by the current design practice and methodology. As a currently developing area there is great potential for innovation in modular structures and several key research areas are identified for further work.

Fiber Reinforced Polymer (FRP) composite products such as Carbon FRP (CFRP) or Glass FRP (GFRP) have been intensively studied for strengthening reinforced concrete (RC) and masonry structures. It has been reported that FRP strengthening is effective to enhance the structural load-carrying capacity. Basalt FRP (BFRP) is a promising material for the application to structure strengthening with its advantages of low cost, corrosion resistant and sound mechanical property, but only limited studies of using Basalt FRP to externally strengthen RC beam are available in the literature. This study is to experimentally explore the effectiveness of application of Basalt FRP to strengthen RC beam under three-point bending test. The damage modes and structural response of unstrengthened and BFRP strengthened RC beams were recorded and identified. The effects of various BFRP wrapping schemes, U-jacket anchorage and epoxy adhesives on the flexural capacity of RC beams were analysed and discussed. In addition, the formulae used to predict the flexural behaviour of RC beam strengthened by other FRP composites (e.g. CFRP/GFRP) were evaluated for their applicability to Basalt FRP strengthening.

Precast concrete (PC) structures have been popularly used in construction practice and PC beam-column joints are critical for structural integrity and safety. In this study, dynamic responses of one monolithic reinforced concrete (RC) joint and three PC joints with different wet connection configurations were investigated by using a pendulum impact test system. The impact behaviours of monolithic RC and PC joints were examined and compared in terms of failure modes, dynamic responses, and energy dissipation. The effects of various wet connection configurations on the dynamic response of PC joints were discussed and analysed. It is found that the interface damage between PC beam and joint led to the reduced integrity of the PC joints. In addition, numerical models of beam-column joints were developed by using software LS-DYNA and calibrated by the test data. The calibrated numerical model was used to investigate the influences of various wet joint configurations on its performance subjected to impact at different locations. Numerical results showed that the shear key and interface rebar employed for wet connections were beneficial to resist shear-governed damage but less effective in resisting flexural-governed damage induced by impact loads. Therefore, the wet connections should be properly designed for PC joint to resist the designated impact loading scenarios.

This study investigates the shear capacity of fibre-reinforced geopolymer concrete (GPC) beams subjected to impact loads. For easy examination of the shear capacities, GPC beams, as well as two reference beams made of ordinary Portland cement (OPC) based concrete, without stirrups were prepared and subjected to the drop-weight impact tests with different contact conditions (direct contact and rubber pad contact). In the case of the beams under direct contact, the failure mode was observed to be a purely diagonal shear failure. The change in concrete material from OPC concrete to GPC showed a marginal effect on the impact response of the beams. Adding fibres into the GPC matrix improved considerably the post-failure behaviour of the beams. The beams reinforced with fibres exhibited not only less concrete spalling and fragmentation but also much higher reaction forces and the second impulse of the impact force. However, the fibre reinforcement seemed to have only a minor effect on the local and contact stiffness of the beams and thus the first impulse of impact force of all the beams was quite similar. The fast Fourier transform (FFT) analysis showed that the adoption of rubber pad contact reduced the highest dominated frequency of impact force from 2.5 kHz to 0.5 kHz. Using rubber pad contact led to the change in the failure pattern of the beams from the purely diagonal shear to the flexure-shear combined failure. The methods used for estimating the imparted and absorbed energy were compared and evaluated. The analysis results demonstrated that the method based on the impact force vs displacement yielded inaccurate results when the inclination angle between the drop hammer and the beams increased. Therefore, this study suggests that the variation in the kinetic energy of the drop hammer should be used to calculate the imparted energy to the impacted beam.

Metaconcrete consisting of engineered resonant aggregates has been adopted to mitigate wave propagation and attenuate dynamic response due to its wave filtering characteristics. Resonant aggregates made of solid cores coated with a relatively soft material can be used to achieve designable attenuation performance. So far, the damping properties of structures made of metaconcrete have not been investigated. Moreover, the current literatures that studying the wave filtering effect of metaconcrete structure concentrate on the 1D stress wave attenuation in the axial direction of the structural members. The dynamic response of metaconcrete structure subjected to transverse impulsive loading is not well studied yet. Therefore, this study investigated the damping property and dynamic response of cementitious metaconcrete with resonant aggregates made of rubber-coated steel balls (RCSB) subjected to transverse impulsive loads. A total of nine beam specimens were prepared, made of plain mortar, mortar with non-resonant inclusions and metaconcrete with various volume fractions of RCSBs (i.e., 9.2%, 18.4% and 22.9%) and different sizes of RCSBs (i.e., 22 mm, 18 mm and 15 mm). Two boundary conditions (i.e., cantilevered and clamped support) were adopted in the tests. The influence of periodic and non-periodic RCSB distributions was also analysed. The effectiveness of metaconcrete on the response attenuation subjected to different transverse impulsive loading intensities was examined. Furthermore, the bandgap characteristics obtained from the experiment were compared with the numerical prediction using COMSOL Multiphysics to verify the existence of bandgap in metaconcrete beam under dynamic transverse loading.

This study numerically examines the prospects of replacing steel tendons with fibre reinforced polymer (FRP) tendons in precast segmental concrete girders/beams (PSCBs) for mitigating the corrosion damage to precast structures using finite element (FE) software Abaqus. This is the first study in the published literature that successfully builds an experimentally-verified 3D FE model of dry-joined PSCBs internally prestressed with unbonded FRP tendons to thoroughly investigate the beam’s flexural behaviour. The effect of segments’ interface imperfection on the initial stiffness of PSCBs was successfully captured in this study. The distinguished working mechanisms between monolithic and segmental beams, and between FRP and steel tendons in both tension- and compression-governed cases were comprehensively discussed. An intensive parametric study was also conducted to examine the effect of primary parameters (effective prestressing stress, prestressing reinforcement amount, span-to-depth ratio and different types of FRP tendons) on the flexural response of PSCBs. The results have proven that commonly available CFRP tendons (Young’s modulus Ep = 145 GPa) can well replace steel tendons in PSCBs while high-modulus CFRP tendons (Ep = 200 GPa) should be used with caution to ensure the PSCBs can achieve sufficient deformability. Moreover, among some existing models, ACI 440.4R-04′s model gave the most accurate predictions of the ultimate stress of unbonded FRP tendons (fpu) in PSCBs compared to the numerical results but its estimation was slightly unconservative and scattered. A new bond reduction factor was, hence, proposed for better prediction of fpu of FRP tendons in PSCBs. The ultimate stress of unbonded FRP tendons in PSCBs should be limited to 75% of the tensile strength of the tendon in design to account for the deformation concentration at the joints and the brittle failure characteristics of FRP tendons.

This study proposes novel bio-inspired fractal multi-cell circular (BFMC) tubes for energy absorption. The inner structures of the proposed BFMC tubes were constructed based on the fractal tree-like forms found in many biological structures such as giant water lily and dragon blood tree. The crashworthiness performances of the proposed structures with different fractal orders and mass were numerically investigated. The numerical results indicated that the specific energy absorption (SEA) increased with the fractal order and the SEA of the 2nd-order BFMC tube was 35.43% higher than that of the conventional multi-cell circular tube. Furthermore, the complex proportional assessment (COPRAS) method was adopted to optimize the performance of the BFMC. The results demonstrated that the proposed structure with four number of tree-like branches and 2nd-order fractal provided the best performance. Finally, a theoretical derivation of the mean crushing force (MCF) was developed for the proposed tubes based on the simplified super folding element theory. The theoretical results of MCF agreed well with the numerical results. The findings of this study provide an effective guide for using the biomimetic approach with the fractal tree-like forms for the design of a multi-cell energy absorber with high energy absorption efficiency.

Metaconcrete is a new type of concrete made by partially replacing natural aggregates with locally resonant engineered aggregates to create frequency bandgaps to resist target impulsive loads. The engineered aggregate consists of solid core coated with a relatively soft material to activate the resonant behaviours of inclusion at the desired frequencies, thus trapping wave energy to attenuate stress wave propagation. Several studies on the characteristics and behaviours of particular metaconcrete have been reported in the literature, but there is a lack of systematic study on how the configurations of engineered aggregates influence the bandgap properties and the stress wave attenuation performance of metaconcrete structures subjected to impulsive loading. In this study, bandgap regions in metaconcrete with various configurations of engineered aggregates are calculated by using software COMSOL Multiphysics, and the influences of geometric and material parameters of engineered aggregates, e.g., core size, coating thickness, core density and coating modulus on the bandgap region are discussed. The influences of engineered aggregates configurations on the stress wave attenuation of metaconcrete rod structure are numerically investigated by using finite element code LS-DYNA. A flowchart to design engineered aggregates with the integration of multiple resonant frequencies is proposed to enhance the attenuation performance of metaconcrete rod structure. The results from this work facilitate the design of metaconcrete with broader bandgap regions and improve the damage mitigation effectiveness when subjected to impulsive loading.

The impact response of reinforced concrete (RC) beams has been intensively investigated by impact tests with various setups. Given the same impact energy, different setups of drop-weight impact tests might lead to different measurements and observations of identical RC beams including the impact force, reaction force and displacement, implying the obtained impact test results depend on not only the impact energy and structure itself, but also the test setups. Therefore, it is essential to understand the measurement accuracy, reliability, and controllability of drop-weight impact tests for a successful impact test design and interpretation of test results on RC beams. This study examines the effects of various test setups and critical factors on the impact response of RC beams. Recommendations for the processing and interpretation of test results with respect to the configuration of the test setup, including the location of load cells, mass and shape of the impact head, interlayer, and boundary condition are made for drop-weight tests. The mechanism of the negative reaction force often observed in impact tests has been unveiled for a better understanding of the impact problem.

This study conducts an experimental and numerical investigation on the failure and impact resistance of plain and fiber-reinforced polymer-confined concrete. The impact resistance of concrete cylinders wrapped with different types of fibers including carbon fiber and glass fiber is examined. Drop-weight tests are utilized to conduct the impact tests while the numerical simulation is conducted using LS-DYNA. The experimental and numerical results have proved that fiber-reinforced polymer can be efficiently used to improve the impact resistance of concrete cylinders. In general, fiber-reinforced polymer ruptures at a lower strain than those in static tests and the rupture strain of glass fiber is much higher than that of carbon fiber. The findings in the experimental tests are confirmed by the numerical results. Glass fiber, therefore, exhibits a much better performance than carbon fiber. It is recommended to use glass fiber to enhance the impact resistance of concrete structures strengthened with fiber-reinforced polymer. In addition, the stress evolution of the specimens is analyzed to investigate the failure mechanism.

A novel Kirigami modified corrugated core was proposed recently and its superior crushing performance under static loading was demonstrated. The proposed core is modified from the conventional corrugated core using Kirigami design, where a portion of the corrugated sheet is cut and then folded vertically. The vertical fold-ins of Kirigami modified corrugated core provide extra support and constraints to the adjacent un-folded cell walls, which increase the crushing resistance of a unit cell up to 10 times as previously studied. However, for a panel with multiple unit cells, its longitudinal flexural stiffness and impact resistance could be affected because of the fold-ins. This study investigates its performance and energy absorption under dynamic crushing through pendulum impact tests. Four configurations of panels, including laminated flat plate (FL), conventional corrugated (CC), Kirigami modified corrugated 1 (KC1) and Kirigami modified corrugated 2 (KC2) were tested. Different impact mass, velocities as well as impacting locations were considered. Impact force and rear face centre deflection were measured and compared to evaluate the impact performance of the panels. Superior impact resistance was demonstrated for proposed KC panel over CC panel under all impact scenarios.

High Volume Fly Ash (HVFA) concrete enables the utilization of fly ash (FA) to diminish greenhouse gas emission by decreasing the demand of ordinary Portland cement. Structures made of HVFA concrete, such as roadside barriers, tunnel cushions and building walls could be subjected to impact and blast loads during service life. Thus, dynamic performance of HVFA concrete is worthy of investigating for better analysis and design of concrete structures. This paper presents the quasi-static and dynamic properties of HVFA concrete containing FA contents of 40 and 60% (by wt.) as partial replacement of cement. The effect of 2% (by wt.) nano silica (NS) on the quasi-static and dynamic properties of HVFA concrete is also studied. The dynamic compressive tests are carried out by using a split Hopkinson pressure bar (SHPB) with 100 mm diameter. The failure processes and patterns as well as stress–strain curves of plain and HVFA concretes under different strain rates are compared. The strain rate effects on the compressive strength, modulus of elasticity and energy absorption capacities are analysed. The experimental results show that quasi-static and dynamic performances of HVFA concrete are enhanced by the addition of NS. With the increase of FA content, the damage level becomes more severe, and modulus of elasticity and energy absorption capacities of HVFA concretes become lower at the similar strain rate. Dynamic increase factors (DIF) of compressive strength for HVFA concretes are quantified and compared with the empirical formulae recommended by Euro-International Committee for Concrete (CEB) for normal concrete. Adding NS leads to lower DIF for compressive strength of HVFA concrete. Empirical formulae for DIF of compressive strength, modulus of elasticity and energy absorption capacity of HVFA concretes with and without nano silica as a function of strain rate are proposed. It is worth noting that the NS modified HVFA C60F38N2 in this study has higher compressive strength, modulus of elasticity and energy absorption capacity than the plain concrete (PC), which shows the potential to replace the normal concrete as a sustainable construction material.

This is the first study in the literature which experimentally and numerically investigates the impact behavior of concrete columns reinforced with fiber-reinforced polymer (FRP) reinforcements. The effect of concrete strength (50 MPa vs 100 MPa) and longitudinal FRP ratio on the lateral impact response of the columns was investigated. The experimental results showed that the longitudinal reinforcement ratio strongly affected the failure modes and impact-resistant capacity while the use of high strength concrete (HSC) did not effectively improve the performance of the columns, which on the contrary, might have caused spalling failure due to its brittleness. The peak impact force and displacement of the columns increased linearly with the impact velocity up to their maximum capacity. The longitudinal reinforcement ratio slightly affected the peak impact forces while the concrete strength showed marginal variation. The use of HSC did not effectively reduce the maximum displacement of the columns. The energy absorption of the columns and the impact velocity exhibited an approximately linear relationship regardless of the reinforcement ratio and concrete strength. Different from the static case, the numerical results show three critical sections, i.e. at the impact location and column ends, which need to be carefully designed.

Intermediate crack (IC) debonding is a common failure mode of externally bonded (EB) FRP-strengthened RC beams. This debonding failure initiates at an intermediate crack and propagates towards a plate end. New epoxy anchor was proposed recently by the authors and has shown its effectiveness in enhancing interfacial bonding behaviour and therefore it might be effective to delay or suppress IC debonding failure in RC beams. This study is to experimentally investigate the efficiency of using epoxy anchors for mitigating the IC debonding under three-point bending tests. The application of the new proposed epoxy anchors has advantage of simple installation procedure including pre-drilling holes and then bonding FRP. Totally, five RC beams including one control specimen and four anchored ones were tested. Damage modes and structural response of unanchored and anchored RC beams were evaluated and discussed. The effects of various configurations of epoxy anchors were analysed and discussed. The experimental results show that the load-carrying capacity and the ductility of anchored beams increased by up to 13.12% and 53.31%, respectively, and the strain utilization of FRP can be significantly improved by 43.48% as compared to the control specimen.

Q355 structural steel has been widely used in the construction industry. A typical Q355 welded steel joint consists of three portions, i.e. Q355 base metal material, heat affected zone (HAZ) material and weld metal material. Although the static material properties of the Q355 base metal and weld metal have been intensively investigated, the dynamic material properties of Q355 base metal, HAZ and weld metal are not well understood yet. The lack of understanding of the strain rate effect on the base metal, HAZ and weld metal material may lead to improper design of welded steel structure against dynamic loading. In this study, quasi-static and dynamic tensile tests on the widely used Q355 base metal, HAZ and weld metal materials were carried out to study their material properties with the strain rate up to 234.90 s−1. The failure modes were investigated and compared with the aid of scanning electron microscope (SEM) images. The strain rate effects on the tensile strength, failure strain and elastic modulus of base metal, HAZ and weld metal materials were revealed. With the testing data, empirical formulae based on the Cowper-Symonds model and Johnson-Cook model were fitted by incorporating the dynamic increase factors (DIFs) of tensile strength and dynamic stress flow, respectively. The proposed empirical formulae can be used in numerical modelling of welded steel structures under dynamic loading.

This study numerically investigates the bending response of dry key-jointed precast segmental concrete girders/beams (PSCBs) prestressed with external fiber reinforced polymer (FRP) tendons by using commercial finite element analysis (FEA) software Abaqus/CAE. The experimentally-validated model was used to conduct an intensive parametric analysis with a focus on the second-order effect. There has not been a similar numerical study of PSCBs with external FRP tendons in the published literature yet. The results showed that due to the rectilinear rigid-body bending shape, the behavior of PSCBs with external tendons was similar to that with internal tendons only if placing the deviators next to the opening joints. The second-order effect on the beam’s behavior and the harping effect on the tendon stress at deviators became more obvious when the deviators were located away from the opening joints. Both the second-order and harping effect were proportionate to the beam’s displacement. Therefore, using a high reinforcing index (ω) or a low span-to-depth ratio (L/dp) could mitigate the second-order and harping effect at the ultimate stage because the ultimate displacement of the beam decreased when increasing ω or reducing L/dp. Commonly-used CFRP tendons (Young’s modulus Ep = 145 GPa) were found to be the optimum to replace steel tendons in PSCBs with external tendons because they offered the PSCBs similar strength and ductility compared to steel tendons. The use of high-modulus CFRP tendons (e.g. Ep = 200 GPa) improved the stiffness and strength of PSCBs but greatly reduced the beam’s ductility. Lastly, the analytical analyses showed that the existing models yielded unconservative estimations of the effective depth (dpu) and stress (fpu) of external FRP tendons at the ultimate stage in PSCBs.

This study investigates the performance of monolithic and newly proposed dry beam-column joints using GFRP bolts, GFRP reinforcements, and different types of fibres subjected to pendulum impact. Six specimens were cast and tested with increasing impact velocity until failure. The experimental results have shown that the proposed concrete dry joint reinforced with fibres and GFRP bars showed better behaviour in terms of energy dissipation (up to 51%), reduced damage level, and reduced maximum and residual displacement as compared to the monolithic joint with GFRP reinforcements. The test results suggested that steel bolts and steel reinforcements could be effectively replaced by GFRP bolts and GFRP reinforcements to mitigate the corrosion problem while still satisfy the design requirements for beam-column joints in both strength and ductility. Furthermore, the use of steel fibres (StFs) demonstrated impressive performance in the critical indices such as damage level and displacement at high impact energies, compared to synthetic fibres (SyFs). Meanwhile, the application of SyFs led to greater energy dissipation than that of StFs (between 6 and 30%). The proposed dry joints could be potentially applied in practice to reduce the construction costs and the damaged/deteriorated components would be easily replaced.

A dual-meta panel functioning as a sacrificial cladding is proposed and its blast mitigation capacity is investigated in this study. The proposed panel possesses the potential to generate bandgaps that target at a specific range of frequencies to stop stress wave propagating through the panel, leading to the favourable stress wave mitigation for structural protection. Aside from the unique stress wave manipulation capability, more energy can be absorbed by a combination of plastic deformation and local resonance. The effectiveness of the proposed panel is validated through numerical simulations. An analytical solution of wave propagation in an ideal meta truss bar is derived to validate the numerical model with good agreement. It is found that the proposed dual-meta panel exhibits an increase in energy absorption, a reduction in transmitted reaction force (up to 30%), and the back plate central displacements (up to 20%) compared to other conventional sandwich panels, e.g. sandwich panel with hollow trusses and solid trusses, in resisting blast loadings. In pursuit of optimizing the performance of the proposed panel, parametric investigations are also conducted to examine the influences of the plate thickness, boundary condition, and the blast load profiles including duration and intensity on the transient response of the proposed dual-meta panel.

Ten full-scale field tests were conducted to study the performance of basalt fiber reinforced polymer (BFRP) strip strengthened autoclaved aerated concrete (AAC) masonry walls subjected to vented gas explosions. Three walls i.e. unstrengthened, rear-face strengthened and front-face strengthened wall specimens were prepared for blast tests. The testing data including overpressure time histories of vented gas explosions, displacement time histories, damage characteristics and fragment distribution of each wall specimen were recorded and analyzed. It was found that the rear-face strengthened wall specimen showed the best blast-resistant performances. Three wall specimens under vented gas explosions experienced damage modes of typical two-way flexural deformation along with shattering of AAC blocks at the latter stage of gas explosions. A detailed micro model for masonry walls was developed in LS-DYNA, incorporating material parameters obtained from material tests. The accuracy of numerical model in predicting the responses of masonry walls was validated with the testing data. Parametric studies were also conducted to explore the influences of BFRP strip layouts, strip thickness and fiber types on the performances of masonry walls. It is found that the BFRP strip layout, strip thickness and fiber types affect the resistance capacity of masonry walls significantly.

Extreme wind events caused damages and losses around the world every year. Windborne debris impact might create opening on building envelop, which would lead to the increase in internal pressure and result in roof being lift up and wall collapse. Some standards including Australia Wind Loading Code (AS/NZS 1170:2:2011, 2011) put forward design criteria to protect structures against windborne debris impacts. Structural insulated panel with Oriented Strand Board skin and expanded polystyrene core has been increasingly used in the building industry. Its capacity was found insufficient to resist the windborne debris impact in cyclonic areas defined in the Australian Wind Loading Code. Therefore, such panels need be strengthened for their applications in construction in cyclonic areas. In this study, impact resistance capacities of seven structural insulated panels strengthened with steel wire mesh and basalt fibre mesh were experimentally and numerically investigated. The impact resistance capacities were identified by comparing the damage mode, residual velocity and unpenetrated length of projectile after impact. Experimental results clearly demonstrated the enhancement of the impact resistance capacities of panels strengthened with steel wire mesh and basalt fibre mesh. Finite element model was developed in LS-DYNA to simulate the dynamic response of the structural insulated panels under windborne debris impact. The accuracy of the numerical model was validated with the testing data.

Basalt Fibre Reinforced Polymer (BFRP) has been becoming more and more popularly used in structural strengthening and rehabilitation due to its advantages of high strength to weight ratio, easy to install, and anti-corrosion. During the service life, BFRP strengthened structures might be subjected to dynamic loadings such as blast and impact loads. It is essential to understand the material mechanical properties, especially the dynamic material properties of BFRP for reliable predictions of the performances of BFRP strengthened structures subjected to dynamic loads. Very limited study on the static and dynamic tensile properties of BFRP material is available in the literature. In this study, quasi-static and dynamic tests of the unidirectional BFRP with a unit weight of 300 g/m2 were conducted to examine the material properties of tensile strength, modulus and failure strain at various strain rates. The strain rate sensitivity on the material properties of BFRP was analyzed and discussed. Empirical formulae for the strength, elastic modulus and failure strain of BFRP material were proposed to estimate the dynamic enhancement at different strain rates.

Fiberglass/epoxy laminate or structures strengthened by fiberglass/epoxy laminate might be subjected to dynamic loadings such as impact and blast. Understanding the dynamic material properties of the fiberglass/epoxy laminate is important to predict the behavior of fiberglass/epoxy laminate or its strengthened structure against dynamic loading. In this study, unidirectional quasi-static and dynamic tensile tests on fiberglass/epoxy laminate were carried out to investigate its dynamic material properties. The strain rate for quasi-static and low velocity test varied from 2.08E-05 to 1.04E-01 s −1 . The high speed dynamic tests were conducted by INSTRON® VHS 160/100-20 machine at the strain rate from 2.75 to 115 s −1 . The strain rate effects on the tensile strength, failure strain and Young’s Modulus of fiberglass/epoxy laminate were investigated. Based on the testing data, empirical formulae were derived to predict the dynamic enhancement of tensile material properties of fiberglass/epoxy laminate as a function of strain rates, which can be used to model the dynamic material properties in the numerical simulation of structural responses.

A total of 16 full-scale in-situ tests were carried out to investigate the performances of unreinforced clay brick masonry walls subjected to vented gas explosions. The pressure-time histories of vented gas explosions, displacement-time histories and failure modes of wall specimens in each test were recorded and analyzed. A detailed micro model for masonry wall was developed in the finite element software LS_DYNA 971. The numerical model was validated with the test data and intensive numerical simulations were conducted to explore the influences of boundary condition, bonding pattern and thickness of masonry walls on their performances against vented gas explosions. The results show that the classical yield-line modes dominate failure patterns of masonry walls subjected to vented gas explosions and the dynamic responses of masonry walls are determined by the peak value of overpressure. It is found that boundary condition and wall thickness have great influence on the performance of masonry walls, while bonding pattern has relatively limited influence on its performance. In addition, the recorded gas explosion loads were compared with the predictions from the conventional TNT equivalency method and the methods specified in NFPA 68 and EN 14994. The results indicate both NFPA 68 and EN 14994 approaches give very conservative predictions of peak pressure from gas explosions. The TNT equivalency method also overestimates the peak pressure and predicts a load profile which is significantly different from the test data.

A total of nine full-scale in-situ tests were carried out to investigate the performances of autoclaved aerated concrete (AAC) masonry walls subjected to vented gas explosions. The testing data including overpressure time histories of vented gas explosions, displacement time histories, and damage characteristics of AAC masonry walls in each test were recorded and analysed. It was found that the responses of masonry walls mainly depend on the peak value of overpressure and couple with the time history of gas explosion loads. Typical one-way or two-way flexural mode dominates the failure of AAC walls under vented gas explosions. A detailed micro model for masonry walls was developed in LS-DYNA, incorporating material parameters that were obtained from material tests. The accuracy of numerical model in predicting the responses of masonry walls was verified with the testing data. Parametric studies were conducted to explore the influences of block strength, boundary condition and wall thickness on the performances of masonry walls. The results reveal both wall thickness and boundary condition have significant influences on the response of the masonry wall while block strength has limited effect on its performance. The testing data were compared with the analytical predictions by using design code UFC 3-340-2 and equivalent single-degree-of-freedom (SDOF) methods developed respectively by Biggs and Morison. The results indicate that these predictions on one-way specimens agree well with the testing data, while the performance of two-way specimens is overestimated by using these three methods.

Closed-cell and open-cell hollow spheres were designed to develop lightweight cellular structures with excellent blast resistance, and the mechanical response of the hollow sphere structure (HSS) under blast loading was investigated numerically using ANSYS®/LS-DYNA®17.0. In this paper, the blast wave pressure decay rate was served as the main index of blast resistance while areal specific energy absorption and frame deformation were used as auxiliary indexes. The results indicated that the weight of HSS was reduced by 37.7%–69.8% compared to solid structures with the same physical size, and the blast resistance of HSS was significantly affected by the hollow sphere diameter and wall thickness, frame length and width, opening size and opening density. Closed-cell HSS with smaller hollow sphere diameters and thicker wall, or smaller frame lengths and widths would achieve the optimal blast resistance. Meanwhile, the blast resistance of HSS could be improved by adopting a smaller opening size, but the effect of opening density did not follow any rule, which was affected by the number and position of openings. Comprehensively, the blast resistance of HSS was enhanced when there was opening only at the face blast surface rather than at both the face blast surface and back blast surface. Keywords: Closed-cell hollow sphere, Open-cell hollow sphere, Blast resistance, Parametric design, Numerical simulation

In this study, the compressive strength of recycled aggregate concrete (RAC) was investigated by conducting quasi-static and split Hopkinson pressure bar (SHPB) tests. Three types of RAC sp...

Precast concrete (PC) structure has been increasingly used in construction industry. PC parts are assembled together by using various connection techniques to keep the integrity of the structures. The wet connection is one of the most popular connection techniques for PC beams. The PC beams with wet connections might suffer impact loads due to falling debris in their lifecycle, which could cause the damage or collapse of structures. However, the investigation of the impact performance of PC beams is very limited. In this paper, the PC beams are studied by using the three-dimensional numerical models developed in LS-DYNA. The developed numerical model of PC beam under drop-weight impact is calibrated with the existing testing data from other researchers. In addition, parametric study is conducted to investigate the influence of various parameters on the dynamic performance of PC beams under drop-weight impact. The considered parameters include impact mass, impact velocity and concrete strength. The generated impact force, maximum and residual displacements at mid-span are examined and compared.

For the structural response estimations of modular steel buildings, the shear, axial and moment-rotation behaviours of the inter-module connections are normally simplified and input into the overall numerical model. While linear models have traditionally been used for the simplification, they do not reflect the true non-linear responses of the connections. Through recent studies, improved models have been developed for the structural behaviours of the newly proposed post-tensioned (PT) and interlocking (IL) inter-module connections (IMCs). In this paper, the newly proposed models are implemented in the numerical simulation of a selected modular steel building. The effect of the inter-module connections on the global building responses to simulated time-varying wind loads and earthquake ground accelerations is examined. Hence, the application of the new simplified models is demonstrated, while the performances of the building incorporating the two different connections are compared. The results demonstrate that the new simplified models are well-suited for use in global numerical simulations. The analytical basis of the models allows application to varied connection geometries, and the more accurate connection behaviours contribute to an improved understanding of the global building responses. Inter-storey drift ratio limits, for example, which are not yet defined for modular buildings, are proposed based on the simplified connection behaviours.

The application of fiber-reinforced-polymer (FRP) bars to reinforce concrete structures could mitigate the corrosion-induced damage of steel reinforcements. No study has been reported in open literature on flexure-critical or shear-critical concrete beams reinforced with Basalt FRP (BFRP) bars under impact loads. In this study, six BFRP bars reinforced concrete beams were tested under quasi-static and impact loads. The test results showed the flexure-critical beams experienced the failure mode changing from flexure-governed under quasi-static loads to flexure-shear combined under impact loads. The shear-critical beams still failed in diagonal shear under impact loads, but experienced severer concrete spalling and more critical diagonal cracks on both sides of the beams. The impact performance of concrete beams with higher strength concrete may not be necessarily superior to that of beams with normal strength concrete due to the increased brittleness. Moreover, a numerical model of the tested beams under impact loads was developed and calibrated in LS-DYNA. Numerical results showed increasing tension reinforcement ratio could change the failure mode from flexure-governed to flexure-shear combined along with the reduced maximum midspan deflection. The BFRP bars reinforced concrete beams had comparable impact resistant performance with the conventional steel reinforced concrete beams

The applications of GeoPolymer Concrete (GPC) with basalt-fiber-reinforced-polymer (BFRP) reinforcements could be alternative for conventional structural designs with Portland Cement Concrete reinforced with steel bars for green and sustainable constructions. Very limited studies, however, have been carried out to investigate the performance of GPC beams reinforced with BFRP bars subjected to static loads, and no study of their performance under impact load is available in open literature yet. In this study, ambient-cured GPC beams reinforced with BFRP bars were tested under static and impact loads. Their damage modes, static and dynamic responses were recorded and analysed. The test results showed that the beams experienced flexural failure mode under static load while combined flexure-shear failure mode was observed under impact load. The impact-loading tested beams were further statically loaded to examine their residual capacities. Additionally, numerical models of the tested GPC beams were developed adopting the commonly used concrete material model *Mat_072R3 (KCC model) in LS-DYNA with modified parameters based on the GPC material testing data. The calibrated numerical model was used for parametric simulations. The results showed that with the increased impact velocity, failure mode of the beam shifted from the flexure-governed to punching-shear-governed along with the rupture of longitudinal BFRP bars.

Increased number of studies of the performances of geopolymer concrete (GPC) structures reinforced with fibre reinforced polymer (FRP) under static loadings have been reported recently, aiming at developing an alternative of the traditional constructions with ordinary Portland concrete (OPC) and steel reinforcement because GPC is a sustainable construction material and FRP is corrosion resistant. Study of the dynamic performance of GPC structures reinforced with FRP is, however, very limited. This study experimentally investigates the impact response of ambient cured GPC beams reinforced with different types of fibres and basalt fibre reinforced polymer (BFRP) bars. Four GPC beams reinforced with steel fibres or synthetic fibres and two control beams made of GPC and OPC without fibre reinforcement were cast and cured under ambient conditions. The volume fraction of fibres varied from 0 to 0.5% were used in concrete mix and BFRP bars and stirrups were used for longitudinal and transverse reinforcements respectively. All the beams were tested under drop-weight impact and after impact tests, the damaged beams were monotonically loaded under three-point bending tests to obtain the residual strength. The experimental results demonstrate that the presence of fibres reduced damages in the crushing zone and mitigated the concrete cover spalling at the bottom of the beams. Also, increasing the volume fraction of fibres shifted the crack patterns and failure modes of the beams from shear-flexure to flexural dominance. However, adding fibres had insignificant effects on the peak impact force, reaction forces, and mid-span displacement. The findings from the residual strength tests indicate that the beams with higher fibre dosage which failed in flexural dominance mode under impact loading have smaller residual strength, different from the expected performance observed in the fibre reinforced concrete beams under static load. Discussions are provided to explain these observations.

A novel Kirigami (cut and fold) modified honeycomb structure is proposed in this study, aiming to reduce the initial peak force under out-of-plane crushing while maintaining the high energy absorption capacity, as well as increasing the in-plane crushing resistance. Three aluminium hexagonal honeycomb structures: standard honeycomb (HC), sheet reinforced honeycomb (RHC), and Kirigami modified honeycomb (KHC) structures are prepared and tested under quasi-static compression in three axial directions. The compressive properties of the proposed Kirigami modified honeycomb are compared with standard honeycomb and reinforced honeycomb in three axial directions. Numerical method is employed to adjust the wall thickness of HC so that its relative density is the same as RHC and KHC for fair comparisons on the crushing performances. Numerical model of standard honeycomb (HC) is calibrated and updated with the adjusted wall thickness to compare with the test results of reinforced and Kirigami modified honeycomb structures of the same relative density. The KHC demonstrated significant improvement on energy absorption capability as compared to the other two honeycombs in all three axial directions. Under out-of-plane crushing, KHC does not develop an initial peak force, while its average crushing resistance remains at a similar level as RHC, and is 17.6% higher than that of HC. Under the in-plane 1 compression, the average crushing resistance of KHC is around 5.2 and 7.5 times of that of HC and RHC, with an even lower uniformity ratio. The KHC shows a moderate improvement in crushing resistance in in-plane 2 direction, compared with the other two honeycombs. These results demonstrate the significant improvement of Kirigami modification on the crushing performance of honeycomb structures.

The use of fiber reinforced polymer (FRP) bars in GeoPolymer Concrete (GPC) structures has drawn increasing attention in recent years. The application of GPC with basalt fiber reinforced polymer (BFRP) reinforcements in replacing Ordinary Portland cement Concrete (OPC) and steel reinforcements leads to green and sustainable constructions. Currently, very limited studies have been conducted to investigate the performance of GPC beams reinforced with BFRP bars under static loads, but no study on their performance under impact loads has been reported yet in open literature. In this study, ambient-cured GPC beams reinforced with BFRP bars were designed, cast and tested under static and impact loads. The damage mode and quantitative results such as midspan deflection, reinforcement strain, and impact and reaction forces were recorded and analysed. Test results showed that spiral stirrups led to superior performance of the beams under both static and impact loads as compared to conventional rectangular stirrups. The commonly used concrete material model *Mat_072R3 in LS-DYNA was modified based on test data to model GPC material. With the modified GPC material model, numerical models were developed and calibrated against the impact test results. Parametric studies were carried out to investigate the influences of GPC material strength and longitudinal and stirrup reinforcement ratios on the performance of beams subjected to impact loads. It was also found that using steel bars as the compression reinforcements led to better performance because BFRP bars under shear and compression were vulnerable to splitting damage subjected to impact loads.

Geopolymer as eco-friendly and alternative cementitious material has been intensively investigated. In a previous study, Expanded Polystyrene (EPS) of volume fractions of 10%, 20% and 30% was mixed into the ambient-cured plain geopolymer mortar (GM) to form lightweight geopolymer composite (LGC). The static mechanical properties were tested and reported. The developed LGC can be used in various applications such as road barriers, tunnel cushions and lightweight building products i.e. bricks and panels, which could be subjected to dynamic loads such as impact or blast. Therefore, its dynamic properties need to be investigated. In this study, dynamic compressive properties of LGC were investigated by using O100-mm split Hopkinson pressure bar (SHPB). The failure processes and the failure modes of plain GM and LGC specimens with various EPS contents under different strain rates, as well as the stress–strain curves and the energy absorption capacity were compared. The strain rate effect on the dynamic compressive strength, axial strain at peak stress and normalized energy absorption capacities were compared and analysed. The test results showed that dynamic compressive properties and energy absorption capacity of LGC with more EPS contents were more sensitive to the strain rate. Based on the testing results, the empirical formulae of dynamic increase factor of compressive strength and energy absorption versus strain rate were proposed.

This paper proposes a new lightweight sandwich panel manufactured with Fiber-Reinforced Geopolymer Composite (FRGC) skin layers and PUR foam core for prefabricated buildings. The failure mechanisms of the developed sandwich panel are investigated under flexural bending and edgewise compressive loading to validate the performance of the developed panel. Digital Image Correlation (DIC) technique is used to obtain the deformation and strain during the tests. Two typical failure mechanisms, i.e. shear failure of the core and tensile failure of the skin layers of the one-way sandwich panel under flexural loading are studied by conducting quasi-static three-point bending tests. The influence of the core thickness-to-span ratio of the sandwich panel on shear failure of the core is studied. The test results show that the failure mode transforms from the shear failure of the PUR foam core to delamination between the FRGC skin and PUR foam core, when the thickness-to-span ratio increases from 0.1 to 0.3. The influence of skin thickness-to-span ratio on the skin tensile failure is also studied. Analytical models for the shear failure of the core and the tensile failure of the skin layer are proposed. Furthermore, the failure mechanism of the developed sandwich panel with different thickness-to-length ratios under edgewise compressive loading is studied. It is found that the failure mode changes from the material failure of the FRGC skin to the global buckling when the thickness-to-length ratio reduces from 0.90 to 0.30. Analytical models for predicting the critical failure load under edgewise compressive loading are also proposed.

For the topological diversity, in-plane hexagonal honeycombs show some interesting mechanical properties which can be related to Poisson's ratios. This work trying to understand how Poisson's ratios affects the crashworthiness of in-plane honeycombs. Based on the standard beam theory, the analytical model that predicting Poisson's ratios is derived, from which the crushing strength in terms of Poisson's ratios is further proposed by using one-dimensional shock model. Combining the analytical and numerical method, Poisson's ratios on the critical crushing characteristics as plateau stress, densified strain, Specific Energy Absorption (SEA) has been investigated under crushing speeds range from 5 m/s to 150 m/s which is complied with previous study about in-plane honeycomb crashworthiness. Through observing the wave trapping behavior of honeycombs, some typical deformation modes have been identified and a deformation-mode map is generated by considering critical wave trapping speeds and Poisson's ratio.

Strong wind causes damages and losses around the world. The windborne debris carried by strong wind might impact on building and create openings on the building envelop, which might threaten the occupants and cause further damages to the building. To address this issue, some wind loading codes including the Australian Wind Loading Code (AS/NZS 1170:2:2011) give design requirements. The resistance capacity of oriented strand board skins structural insulated panel was investigated and proved having low resistance to the projectile impact, and could not meet the impact resistance requirement for application in cyclonic region C and D defined in Australian Wind Loading Code. In this study, basalt fibre cloth is used to strengthen oriented strand board structural insulated panel to increase its capacity to resist windborne debris impact. This paper presents experimental and numerical study of structural insulated panel with or without basalt fibre cloth strengthening under windborne debris impact. Five specimens with different configurations were tested. The dynamic responses were quantitatively compared in terms of residual speed of debris after impact. The results indicate that basalt fibre cloth enhanced the resistance capacity of oriented strand board structural insulated panel. A numerical model is developed in LS-DYNA to simulate the debris impact. The testing results are used to verify the accuracy of the numerical model, which can be used in subsequent parametric studies.

Strong winds happen around the world every year and cause enormous damages and losses. Besides large wind pressure, impact from windborne debris on building envelope is a major source of structural damage in strong winds. The debris lifted and carried by wind impacting on building envelop may create openings on building envelope which increase internal pressure of the building, and lead to roof lifting and even total building collapse. Preventing impact damage to structural wall and roof is therefore critical in extreme wind conditions. On the other hand Structural Insulated Panel (SIP) with Oriented Strand Board (OSB) skins is popularly used in the building industry. Previous studies revealed that such SIP panels had weak impact resistant capacity and do not meet the design requirements to resist windborne debris impact specified in Australian Standard (AS/NZS1170.2:2011) for their applications in cyclonic regions. To increase the capacity of such SIP panels against windborne debris impact, basalt fibre cloth was used to strengthen the panel. Laboratory tests found that SIP strengthened with basalt fibre cloth was effective in increasing its impact-resistant capacity. This paper presents the development of a reliable numerical model to predict the impact responses of basalt fibre cloth strengthened SIP panel in LS-DYNA. The accuracy of the numerical model is verified by comparing the numerical and experimental results. The validated numerical model provides a reliable tool to predict basalt fibre cloth strengthened SIPs.