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The assembly of modular containers using building information modelling (BIM) technologies was studied. The purpose of this study was to analyse the literature on prefabricated (prefab) houses and explore the concept of creating a digital prototype of a building based on Huoshenshan hospital using Autodesk Revit software. This hospital was constructed to treat Covid-19 patients in early 2020. The article describes the methodology of installing modular containers and assembly structures using BIM technologies for rapid construction. The results of this study showed that building object implementation depends directly on a proper model with a step-by-step mechanism for installation. Due to the supply of prefab structures at the construction site, both initial project cost and project time can be reduced. Prefab house technology demonstrated the high efficiency of using BIM technology in the assembly of Huoshenshan hospital, which was constructed in 10 days. The need for information modelling data exchange with modern technology and systems, which allows the team to become acquainted with the project before installation work starts at the construction site, is investigated.

Servo-hydraulic actuators are often used in real-time hybrid simulation to impose desired displacements to specimens and to maintain the boundary compatibility between substructures. Previous studi...

Magnetorheological (MR) dampers provide a viable alternative for vibration control of structures subjected to external excitations. Realistic modeling of MR dampers is critical for control ...

To accomplish rapid installation and replaceability, a new type of connector for new fully assembled steel-concrete composite beams was studied. The connectors are fixed on the C-shaped channels of the prefabricated floor slab. The load transfer along the interface of the precast floor slab and the steel beam is primarily achieved through the friction between the beam flange and the channels. Push-out tests were conducted to study the mechanical properties of new composite beam. The effects of different C-shaped channel types, repeated loading and number of connectors were investigated. Test results showed that all the connectors exhibited satisfactory performance. When the section height of C-shaped channel is small, the restraining effect on the connector is more remarkable. The shear strength and shear stiffness of the connectors can be improved by reloading. The formulas for calculating the shear strength derived agree well with the experimental results.

This paper focuses on a new type of precast sandwich wall panels in which the expanded polystyrene (known as EPS) insulation layers are inserted between exterior reinforced concrete panels. The exterior reinforced concrete panels are held through diagonal steel bars to allow the sandwich panel to form the composite action to resist the bending moment demands. To investigate flexural behavior of the sandwich wall panels, four specimens with representative geometries and typical materials were designed. The four specimens included one with the flat exterior reinforced concrete panels and three with the ribbed exterior reinforced concrete panels. The specimens were tested using gradually increased uniformly distributed loads. It is found that all the specimens developed the composite action when resisting the bending moment demands and exhibited the same failure mode. Test results show that the specimens consisting of the ribbed exterior reinforced concrete panels (which had lower mass per unit volume) exhibited reduced flexural resistances at the cracking limit state and the ultimate limit state in comparison with the one with flat exterior reinforced concrete panels. This paper develops a set of analytical models based on the test data and simplified strain/stress diagrams for analyzing flexural behavior of the proposed sandwich wall panel. Result comparisons show that the models can provide reasonable predictions and they can be used for future practice.

This research focused on a new type of seismic damper consisting of replaceable U-shaped steel plates. To investigate behavior of the damper, seven specimens were tested. The test parameters varied in these specimens included geometries and materials of the U-shaped steel plates and the loading protocols. Test results show that the specimens exhibited stable hysteretic behaviors and satisfactory energy dissipating capacities. In addition, this research provided clear evidence that the damper is robust and tolerant to the ruptures in the U-shaped steel plates. Some specimens continued to dissipate significant amounts of hysteretic energy even after formation of the visible ruptures in the U-shaped steel plates. Moreover, this research demonstrated that the damper repaired through replacement of the U-shaped steel plates following a severe earthquake remained satisfactory in a subsequent earthquake. Further, this paper presents the equations for estimating yield strength and ultimate strength of the damper. It was found that the derived equations provide reasonable predictions and can be used for future design.

Shape memory alloys (SMAs) are gaining increasing attentions from earthquake engineering community, due to the superleastic property, which is capable of offering energy dissipation capacity and recentering ability to various structural systems. SMA braced frames (SMABFs) are emerging as promising frames with advanced seismic resilience. Recently, the performance-based plastic design (PBPD) method was developed for such structural system. However, the robustness of this design approach still needs rigorous examinations by addressing the effects of defining different performance targets or using different seismic design spectra in the design procedure. In doing so, examinations were carried out from two perspectives. The first one set various performance targets combining different interstory drift ratio and brace ductility demand in the design procedure based on the design basis earthquake spectrum, and then the resulting SMABFs were subjected to earthquake ground motions corresponding to design basis hazard level. The second one conducted the design procedure at three seismic hazard levels representative of frequently occurred earthquake, design basis earthquake, and maximum considered earthquake, respectively, and then assessed the seismic performance upon earthquakes associated with three seismic intensities. The analytical results show that the designed frames as per the PBPD method always coincide with the performance targets very well, regardless of the prescribed targets and adopted design spectrum. Therefore, this paper provided sound results which successfully demonstrated the high robustness of the previously developed PBPD method for SMABFs.

This study proposes a new type of shear wall, namely, the concrete-filled steel tube composite shear wall, for high performance seismic force resisting structures. In order to study the seismic behavior of concrete-filled steel tube composite shear wall, cyclic loading tests were conducted on three full-scale specimens. One conventional reinforced concrete shear wall was included in the testing program for comparison purpose. Regarding the seismic performance of the shear walls, the failure mode, deformation capacity, bearing capacity, ductility, hysteretic characteristics, and energy dissipation are key parameters in the analysis procedure. The testing results indicated that the bearing capacity, the ductility, and the energy dissipation of the concrete-filled steel tube composite shear walls are greater than that of conventional reinforced concrete shear walls. In addition, the influence of axial compression ratio on the seismic behavior of concrete-filled steel tube composite shear wall is also investigated. It was found that higher axial compression ratio leads to an increase in the bearing capacity of concrete-filled steel tube composite shear walls while a reduction in the ductility capacity.

Steel building frames consisting of tension-only braces have been recently recognized as adequate lateral force resisting systems for use in low-rise buildings in the regions with seismicity. To further promote the use of such systems, this investigation was focused on developing recommendations for calculating the horizontal seismic force demands on the nonstructural components attached to the systems. Specifically, two full-scale three-story experimental models were designed, constructed and tested using shake tables. The two experimental models differed from each other primarily in that one model consisted of the exterior walls with non-negligible contributions to the system lateral stiffness while the other experimental model did not have such exterior walls. A series of shake table tests using the excitations scaled to different intensity levels were performed on each experimental model. It was found that the existing design and analysis methods appear inadequate in predicting the horizontal seismic force demands on the nonstructural components. Based on the test results, a practical model which can well capture the central tendency of the test results and can be integrated into the existing design method was developed. Test results also revealed that the exterior walls with non-negligible contributions to the system lateral stiffness can arouse larger horizontal seismic force demands on the nonstructural components.

Bucking-restrained braces (BRBs) can help limit the maximum transient inter-story drifts of Concentrically Braced Frames (CBFs) under earthquake loading, but they are not effective in mitigating the post-earthquake residual inter-story drifts in the CBFs. Shape Memory Alloys (SMAs) can exhibit flag-shape hysteretic loops with zero or negligible residual deformations under cyclic loading, suggesting their excellent superelasticity and energy dissipation capacity. With the limitation of the conventional BRBs and the favorable feature of the SMAs, it has been questioned that if the SMA braces (SMABs) can be used as alternatives to the conventional BRBs to further reduce the residual inter-story drifts while limiting the maximum transient inter-story drifts in CBFs. Focusing on a six-story demonstration CBF which has representative geometries, the SMABs were designed to enable the demonstration CBF to achieve similar maximum transient inter-story drift responses to the same CBF consisting of the BRBs under the design-level earthquake excitations. Seismic performances of the two designs (with the SMABs and the BRBs, respectively) were investigated through nonlinear static analyses and nonlinear response history analyses based on three suites of ground motion records representing different seismic hazard levels. Analysis results show that the SMABs are as effective as the BRBs in limiting the maximum transient inter-story drifts in the considered CBF but are more effective in reducing the residual inter-story drifts of the CBF. Moreover, it is found that the CBF with the SMABs can achieve a more uniform transient inter-story drift distribution in the system compared with the system consisting of the conventional BRBs. Finally, the advantage of the SMABs over the conventional BRBs is demonstrated through probabilistic analyses and interpretations of the results from the nonlinear response history analyses.

This paper focuses on a new type of exterior wall system for steel building frames. The wall system consists of precast reinforced concrete wall panels that are bolted to the beams of a steel building frame and are equipped with the inter-panel steel tee energy absorbers. The precast wall panels and the steel tees are expected to remain elastic and absorb hysteretic energy under the frame inter-story drifts caused by earthquakes, respectively. To demonstrate the perceived benefits of the exterior wall system and investigate the behavior of the steel tee energy absorbers, a group of five specimens with each consisting of a steel frame, a pair of precast wall panels and a set of six steel tee energy absorbers were designed, constructed and tested. The test parameters varied among the specimens were the geometries of the steel tee energy absorbers and the technology adopted to develop them. The steel frame and the precast wall panels were re-used in all specimens. Each specimen was tested through a two-phase loading program which imposed the inter-story drift demands with progressively increasing and constant peak amplitudes, respectively. All the specimens sustained the maximum inter-story drift angle of 0.05 rad or larger and exhibited a stable energy dissipation response. The tests demonstrated the damage free response of the precast exterior wall panels as well as the replaceability of the steel tee energy absorbers. Based on an idealized curvature distribution in the webs of the steel tee energy absorbers, the classic beam theory, and the virtual work theory, this research established a simplified model for computing the strengths of the steel tee energy absorbers as well as their contribution to the lateral strength of the frame. The model was found to be able to provide acceptable predictions for the tested specimens and it is recommended for future design.

Self-centering concentrically braced frames (SCCBFs) are emerging as one of the high performance seismically resistant framing systems, known for the capability of controlling peak seismic demands and eliminating residual deformation. In the process of developing SCCBFs, shape memory alloys (SMAs) are deemed as the potential candidate for the key component of SCCBFs, due to the excellent superelastic capacity and desirable flag-shape hysteresis. For the SCCBFs using SMA braces (SMABs), an economical and effective design approach based on the performance-based plastic design was recently derived. This study aims to extend the ad hoc design approach to low-to-high rise multi-story SCCBFs using SMABs, and to examine its generality. As such, the seismic performance of four SCCBFs with various story numbers was intensively analyzed by subjecting them to ground motion records corresponding to design-basis earthquake. The analysis results show that all the resulting frames were capable of coinciding well with the prescribed targets of peak interstory drift ratios and ductility demands. In addition, the structures returned to at-rest positions without producing residual deformation after earthquake events. Therefore, this study successfully validates the applicability of the ad hoc design approach to SCCBFs with various story numbers.

This research focused on development of a new type of re-centering damper consisting of the Ni-Ti Shape Memory Alloy (SMA) rods and friction wedges. Compared with the other existing types of SMA-based dampers, the proposed damper offers an improved energy absorption capacity. In addition, strength and deformation capacity of the proposed damper can be conveniently adjusted if needed. To verify the perceived benefits of the damper, a series of tests were performed on an experimental specimen. It was found that the proposed damper can exhibit stable hysteretic energy dissipation response and reliable re-centering performance without developing any visible damage in the damper components. The test results also show that the damper is not sensitive to the different loading protocols imposed. Beyond the experimental work, a theoretical model for the proposed damper was established and validated by the test results. The theoretical model can be used to design the damper in the future. Furthermore, a three-dimensional computer model was developed for the tested damper. The computer model was found to be able to accurately replicate the nonlinear responses of the experimental specimen. The modelling approaches and assumptions adopted in the computer model can be used for future analysis and design.

This research focused on a new type of bolted base connection for wide-flange columns. The base connection consists of a pair of steel angles and a shear plate that connect the wide-flange column to the foundation. To investigate the behavior of the base connection under the combined column axial compression and cyclic lateral load causing the strong-axis bending in the column, six experimental specimens were designed, constructed, and tested. The test parameters varied in the specimens included the column axial compression and the technology used to manufacture the angles used in the bolted base connection. All the specimens were tested using the same cyclic lateral loading protocol. It was found that all the specimens behaved in the same ductile manner while dissipating significant amounts of hysteretic energy. Moreover, all the specimens stably achieved the ultimate connection rotation of 0.06 rad without experiencing any in-cycle strength degradations. This investigation experimentally demonstrated the replaceability of the angles in the bolted base connection. The tests also provided clear evidence that the hot rolled, cold folded and welded angles can be alternatively used in the bolted base connection to sustain the connection rotation up to 0.06 rad. This research further derived a simplified analysis model to capture the backbone response of the bolted base connection. Result comparisons show that the analysis model can provide reasonable approximations.

This paper focuses on a new type of base connection for wide-flange columns. The base connection consists of a pair of steel angles and a shear plate that connect the flanges and the web of a wide-flange column to the foundation through a set of high-strength bolts, respectively. To investigate the response of the bolted base connection under the combined column axial compression and weak-axis lateral load, three specimens were prepared and tested. The test parameter varied in the specimens was the technology used to develop the angles in the bolted base connection. The three specimens adopted the hot rolled angles, the angles cold folded from steel plates, and the angles welded from steel plates, respectively. All the specimens were tested with the same axial compression and the same cyclic lateral loading protocol. It was found that all the specimens behaved in the same ductile manner while dissipating significant amounts of hysteretic energy. Moreover, all the specimens sustained the weak-axis rotation of 0.06 rad without developing any in-cycle strength degradations. The tests provided clear evidence that the cold folded and welded angles can be used as the surrogates to the hot rolled angles in the bolted base connection under the considered combined loading. This research further established a simplified model to approximate the backbone response of the lateral resistance of the bolted base connection under the considered combined loading. Result comparisons show that the simplified model can provide reasonable estimates.

This paper focuses on a new type of steel-concrete composite beams consisting of cast-in-place concrete slabs on Precast Prestressed Concrete Decks (PPCDs). To evaluate flexural performance of such composite beams, this research team conducted an experimental investigation on twelve specimens. Test results show that the composite beams with PPCDs can exhibit desirable and stable flexural performance under monotonic loading. Based upon the test results, this paper also evaluates the influence of some key design parameters (e.g., concrete slab thickness, amount of shear studs and longitudinal reinforcement ratio) on flexural performance of the composite beams.

This article focuses on evaluating the adequacy of a seismic rehabilitation technology which adds rocking cores to deficient steel concentrically braced frames in near-fault regions. Two demonstration buildings were rehabilitated with the technology. Seismic performance of the rehabilitated buildings was evaluated through numerical simulations. Analysis results suggest that the code-compliant concentrically braced frames may be vulnerable to collapse under the fault-normal components of the near-fault ground motions, approximately having a probability of exceedance of 10% in 50 years. It is found that the Rocking Core technology is effective in reducing the inter-story drift responses of the demonstration buildings under near-fault earthquakes. The rehabilitated systems can further benefit from the use of hysteretic energy dissipating links between the rocking cores and existing concentrically braced frames. This article also addresses the influence of the rocking cores on modal properties of the rehabilitated buildings. It is found that the rocking core with moderate stiffness does not significantly alter the modal properties of a rehabilitated concentrically braced frame.

This investigation assesses adequacy of the Stiff Rocking Core (SRC) technology for rehabilitating steel Moment Resisting Frames (MRFs) vulnerable to drift concentrations and soft-story failures. The technology installs a single or multiple SRCs pinned to the foundation and connected to a deficient multi-story steel MRF to re-distribute seismic forces along its height and create more uniform inter-story drift and ductility demand distributions. This research team implemented the SRC technology in two archetype steel MRFs including one three-story and one nine-story. Results from nonlinear static analyses show that the SRC technology can reduce inter-story drift concentration in both steel MRFs regardless of the seismic force distributions and drift limits considered in design. Additionally, the SRC extending along the entire height of a steel MRF is more preferable than the one extending over the bottom portion of the system, although these two SRC options can be both valid in many cases.

Precast Segmental Reinforced Concrete Walls (PS-RCWs) are construction units recently developed for modern modular construction. A typical PS-RCW is comprised of cast-in-place concrete enclosed by two precast concrete panels. This paper experimentally investigates performance of the PS-RCWs under eccentric compressive loading. Eight specimens including seven PS-RCW specimens and one conventional cast-in-place reinforced concrete wall specimen were tested. Test results show that the bonding strength between the cast-in-place concrete and precast concrete panels controls the failure modes of the PS-RCWs under eccentric compressive loading. It is found that a PS-RCW with sufficient bonding strength between the cast-in-place concrete and precast concrete panels exhibits the more favorable failure mode in which a plastic zone forms in the wall as a result of the eccentric compressive loading. Testing data also revealed that the classic strain and stress diagrams assumed for reinforced concrete members under eccentric compressive loading can be extended to PS-RCWs. An analytical model recommended in the Chinese National Code for Design of Concrete Structures (GB50010-2012) was found to provide reasonable predictions for strength of the PS-RCWs under eccentric compressive loading and it is recommended for future practice.

Based upon elastic perfectly plastic oscillators, this research investigates the influence of cumulative damage on seismic response modification factors. To take into account the cumulative damage due to hysteretic energy absorption, the Park–Ang damage index was adopted as the damage measure. A large number of iterative nonlinear response history analyses were conducted for the oscillators with periods and other features representative of conventional civil structures. Analysis results show that a significant portion of the total damage in a system reaching its damage limit state is due to hysteretic energy absorption. Consequently, the maximum tolerable ductility demand in the system under earthquake loading is lower than its ductility capacity determined under the monotonic loading condition. Moreover, the existing formulae for calculating response modification factors are shown to be inadequate to capture the effect of cumulative damage. A new method was developed for improved estimates of the response modification factors.

Structural assessment for collapse is commonly approached by observing the failure or collapse of systems fully incorporating degradation. Challenges however exist in the performance indicator or damage measure due to compound impacts of uncertainties of external (seismic excitation) and internal (structural properties) characteristics with degradation behavior. To account for the impacts of uncertainties, the state-of-the-art kriging nonlinear autoregressive with exogenous (NARX) model is explored in this study to replicate the response of nonlinear single-degree-of-freedom systems. The generalized hysteretic Bouc-Wen model with internal uncertainties is selected to emulate the stiffness and strength degradation. A probabilistic stochastic ground motion model is introduced to represent the external uncertainties. The global terms of NARX model are selected by least-angle regression algorithm and the kriging model is utilized to surrogate uncertain parameters into corresponding NARX model coefficients. The predictions of kriging NARX models are further compared with that of the polynomial chaos nonlinear autoregressive with exogenous input form model as well as Monte Carlo simulation. The comparisons show that kriging NARX model presents an effective and efficient meta-model technique for uncertainty quantification of systems with degradation.

Superelastic shape memory alloys (SMAs) are capable of recovering large inelastic deformation and dissipating energy under loading reversals, and therefore present promising application in vibration control of engineering structures subjected to dynamic loads. Properties of SMAs are often optimised based on experimental results and treated as deterministic for dynamic analysis of structures with SMA-based devices. This study applies the Metropolis–Hasting algorithm to characterise the uncertainties within an SMA material model and to provide insight into its parameter uncertainty. Cyclic tests of SMA bars are first conducted and the experimental data are analysed using the Markov chain Monte Carlo method. The statistical properties of SMA model parameters are calculated based on posterior parameter distributions. The influence of SMA model parameter uncertainty is further explored on energy dissipation capacity under cyclic tests. The first four L-moment method is applied to transform the posterior parameter distributions into standard normal distribution to further evaluate the influence of model parameter uncertainty on energy dissipation in dynamic analysis.

This paper focused on the panel which sandwiches an Expanded Polystyrene (EPS) layer between two Steel Reinforced Concrete Layers (SRCLs). The EPS layer provides thermal insulation in the panel while the two exterior SRCLs are connected by Glass Fiber Reinforced Plastic (GFRP) shear connectors to form the composite action and hence achieve a higher flexural resistance in the panel. Four types GFRP shear connectors which consist of diagonal web members, webs with circular perforations, webs with slotted perforations and solid webs, respectively, were considered in this research. To experimentally address the flexural responses of the panels with the four types of GFRP shear connectors, four full-scale experimental specimens were constructed and tested. The test results show that generally any of the four GFRP shear connectors can enable the panel to exhibit satisfactory flexural performance although the GFRP shear connectors with the solid webs tend to increase the ultimate flexural resistance of the panel. Beyond the experimental work, an analysis model based on the transformed cross-section approach and elastic beam theory was developed for capturing the flexural response of the panel up to the cracking limit state. Moreover, an analysis model based on the assumed strain and stress diagrams was established to compute the ultimate flexural resistance of the panel.

This research focuses on a new type of buckling-restrained brace (BRB) with replaceable steel angle fuses. The proposed BRB offers ease of postearthquake examination of fuse damage, conveni...

Composite Lightweight (CL) insulated walls have gained wide adoption recently because the exterior claddings of steel building frames have their cost effectiveness, good thermal and structural efficiency. To investigate the seismic behavior, lateral stiffness, ductility and energy dissipation of steel frames with the CL infill walls, five one-story one-bay steel frames were fabricated and tested under cyclic loads. Test results showed that the bolted connections allow relative movement between CL infill walls and steel frames, enabling the system to exhibit satisfactory performance under lateral loads. Additionally, it is found that the addition of diagonal steel straps to the CL infill wall significantly increases the initial lateral stiffness, load-carrying capacity, ductility and energy dissipation capacity of the system. Furthermore, the test results indicate that the lateral stiffness values of the frames with the CL infill wall are similar to those of the bare steel frames in large lateral displacement.

Although ground motion duration is generally perceived to influence structural response, it has not been explicitly considered in current seismic design practice. This paper investigates duration effect of ground motions on ductility and hysteretic energy dissipation demands on structures. Spectrally equivalent ground motions were first generated from historical records to decouple the effect of duration from those caused by other characteristics of ground motions. The spectrally equivalent ground motions were then grouped into the Short-Duration (SD) and Long-Duration (LD) suites based their significant durations for Response History Analyses (RHA) of elastic-perfectly plastic Single Degree of Freedom Systems (SDOFS). Results from RHA show that ground motion duration has a negligible influence on the central tendency of ductility demands but a significant impact on that of hysteretic energy dissipation demands. Statistical evaluations and hypothesis tests further demonstrate that the LD ground motions lead to higher hysteretic energy dissipation demands but exert similar level of ductility demands on structures in comparison with the SD ground motions. With the result database from RHA, an empirical model was developed to consider the effect of ground motion duration on hysteretic energy dissipation demands. The empirical model was then integrated into the Park–Ang damage index for determination of the required ductility capacity for a system. Results from parametric analyses show that the empirical model provides reasonable estimates of required ductility capacity. Results from RHA were also used to evaluate adequacy of the FEMA 461 quasi-static cyclic loading protocol for seismic performance evaluation. It was found for elastic-perfectly plastic SDOFS that the FEMA 461 quasi-static cyclic loading protocol is sufficient to exert the hysteretic energy dissipation demands due to SD ground motions but may be inadequate for consideration of the hysteretic energy dissipation demands due to LD ground motions.

For studying the hysteretic behavior of steel frames with sandwich composite (SC) panels, an experiment was implemented. A full scale one-bay and one storey specimen was tested under cyclic loading. Seismic behaviors were evaluated in line with the failure pattern and damage process of the specimen. Based on the experimental data, hysterics loops, skeleton curves, curves of strength degradation, and curves of stiffness degradation, ductility index and viscous damping coefficient were obtained. It is indicated that although the failures of panels mostly occurred around the embedded parts, SC panels exhibit a better integration than traditional walls. The connection between panel and steel frame is crucial to the corporation of the two parts. Finally, the suggestions for seismic design were put forward based on ductility index analysis and structures' energy dissipation. Moreover, FEA study was also carried out by using ABAQUS. A good agreeement was achieved between the experimental data and the numerical result in FEA. Finally, the useful information was got according to simplified caculation model. Only 7% of lateral stiffness is considered into calculation when panel is bolted to the frame at four corners of the frame.

This paper presents a simplified model to study post-buckling behaviours of the axially restrained steel column at elevated temperatures in fire. The contribution of axial deformation to the curvature of column section is included in theoretical equations. The possible unloading at the convex side of the column when buckling occurs is considered in the stress-strain relationship of steel at elevated temperatures. Parameters that affect structural behaviours of the axial restrained column in fire are studied. The axial restraint cause an increase in the axial force before the column buckles; the buckling temperature of restrained columns will be lower than non-restrained steel columns. However, the axial force of a restrained column decreases after the column buckles with the elevation of temperatures, so make use of the post-buckling behaviour can increase the critical temperature of restrained columns. Columns with temperature gradient across the section will produce lower axial force at elevated temperatures.

Four-point bending tests including twelve specimens were carried out to investigate the flexural rigidity, failure mode and ultimate capacity of the steel-concrete composite beam with a composite floor slab comprising 30 mm thick precast prestressed concrete panels and T-shaped concrete ribs (PPCRP). The test parameters included support length of PPCRP, thickness of the composite floor slab, longitudinal compressive reinforcement ratio, degree of the shear connection and the direction of T-shaped concrete rib. Strain distribution along the depth of mid-span section was obtained by strain gauges. Based on the moment-deflection curves of specimens, it was showed that flexural behavior of precast composite floor slab was similar to that of concrete floor slab cast in-situ during the elastic stage. Two failure phenomena were observed: i) Interface bond slip between the precast panel and the cast in-situ layer; ii) Diagonal shear crushing in one shear span. Compared with the floor slab cast in-situ, a slight decline in the ultimate flexural capacity was observed for the composite beam with composite floor slab. Analyses about the effects of all parameters on composite beams’ rigidity and ductility were presented.

Sandwich composite panels are generally fabricated of two concrete wythes separated by a layer of lightweight polystyrene foam. The concrete wythes are connected to each other by steel truss shear connectors. These panels are widely used as the exterior cladding of steel residential houses due to their economical advantages, superior thermal and structural efficiency. In conventional analysis, the infilled composite panels are considered as non-structural parts in steel frame and their effects are ignored in Chinese Code. However, it has been widely recognized that the existence of composite panels within the interior of the buildings considerably improve the lateral stiffness, ultimate strength and energy dissipation capacity against earthquakes. In order to investigate the seismic behavior of steel frame infilled with composite panel, two specimens with one-bay and one-story were performed under reversed cyclic lateral load. Test results showed that the contribution of composite panels to the steel frame lateral stiffness could reach up to 32% and the equivalent damping coefficient could exceed 0.05. The failures of panels mostly occurred around the embedded parts, but panels exhibit a better integration than traditional walls Finite element analysis (FEA) was carried out by using ABAQUS software to study the seismic performance of two story and one bay steel frame infilled with sandwich composite panels. In this analysis, the effects of parameters selected i.e. thickness of panel, ratio of height to width of panel, type of connection between panel and steel frame, ratio of strength and stiffness of panel to strength and stiffness of steel frame, axial compression ratio and boundary conditions were investigated. It was found from FEA results that steel frames infilled composite panels had a higher ultimate strength and lateral stiffness compared with pure steel frame. The type, strength and stiffness of connections between panels and steel frames were the primary parameters affecting seismic performance of overall structural system. Based on FEA results, seismic design recommendations of steel frame infilled with composite panels were proposed and Chinese current standard may be improved by considering the effect of infill panels.

The dissertation explores how to transform an on-site construction robot from the conceptual stage to the near market uptake stage. The featured case study is based on the first phase of the consultancy project funded by the Construction Industry Council Hong Kong (CIC). The project explored the potential to implement automation and robotics technologies in the public housing construction sector. The outcome of the study can be summarized as a comprehensive guideline that can be used as a development decision tool to assists the construction industry in the future. Diese Dissertation befasst sich mit der strategischen Entwicklung eines Vor-Ort-Roboters vom Konzept bis hin zur Marktreife. Die beschriebene Fallstudie basiert auf einem vom Construction Industry Council finanzierten Beratungsprojekt, das die Implementierung von Automatisierungsprozessen und Robotik im Sektor des sozialen Wohnungsbaus untersucht. Das Ergebnis dieses Projekts kann dem zukünftigen Bauwesen als umfassende Richtlinie zur Entwicklungs- und Entscheidungshilfe bei der Evaluierung von Automatisierungsprozessen und deren Implementierung dienen.