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In this study, a novel diagonally inserted bar-type basalt fiber reinforced polymer (BFRP) connector was proposed, aiming to achieve both construction convenience and partially composite behavior in precast concrete sandwich panels (PCSPs). First, pull-out tests were conducted to evaluate the anchoring performance of the connector in concrete after exposure to different temperatures. Thereafter, direct shear tests were conducted to investigate the shear performance of the connector. After the test on the individual performance of the connector, five façade PCSP specimens with the bar-type BFRP connector were fabricated, and the out-of-plane flexural performance was tested under a uniformly distributed load. The investigating parameters included the panel length, opening condition, and boundary condition. The results obtained in this study primarily indicated that 1) the bar-type BFRP connector can achieve a reliable anchorage system in concrete; 2) the bar-type BFRP connector can offer sufficient stiffness and capacity to achieve a partially composite PCSP; 3) the boundary condition of the panel considerably influenced the out-of-plane flexural performance and composite action of the investigated façade PCSP. [ABSTRACT FROM AUTHOR]

A hybrid structure constructed by replacing external steel beams and columns in the steel frame (SF) to precast concrete shear walls with insulation (PCSWs) and precast concrete cladding panels (PCCPs, SFPCSW) is proposed in this paper to avoid the problem of columns protruding from walls and PCCPs directly connected with SF. Numerical models of the SF and SFPCSW structures are established in ETABS software based on an 18‐story assembled steel residential building to investigate the seismic performance and collapse resistance capacity of SFPCSW. Time history analysis results show that the SFPCSW exhibits bending‐shearing lateral deformation and has more uniform interstory drift ratios than the SF. Under major earthquakes (i.e., probability of exceedance of 2% in 50 years), the damage of SF is concentrated in stories 1–6; for SFPCSW, the plastic hinges mainly appear in the concrete beams between PCSWs at each story, and the damage in PCSWs and the internal frame is small. Using pinned connections between the steel beam and PCSW reduces the structural lateral stiffness and increases the earthquake load carried by the internal frame. The incremental dynamic analysis results show that the SF and SFPCSW have similar collapse resistance capacities. [ABSTRACT FROM AUTHOR]

This paper proposed a new lateral joint to connect precast concrete hollow‐core slabs (PCHSs) and increase their structural assembly efficiency. The main sensitive parameters are the longitudinal ribs and the number of proposed joints. Out‐of‐plane bending performance tests were conducted on four PCHSs with lateral joints (PCHS‐LJs) to study the effects of the main sensitive parameters on the mechanical properties and failure modes of the PCHS‐LJs. The test results showed that there is no obvious relative slip in the joints between the precast bottom slab and the upper post‐pouring concrete before PCHS‐LJs reaching the ultimate load. The transverse directions of PCHS‐LJs are the main force bearing directions and the cracks are mainly occurred in the longitudinal direction of the specimens, which is similar to the stress characteristics of one‐way slabs. Moreover, the vertical bearing capacities of PCHS‐LJs are increased when decreasing the number of proposed joints or when adding the longitudinal ribs. For the specimens without the longitudinal ribs, a wide transverse crack appears near the first transverse ribs, whereas the specimens with the longitudinal ribs do not exhibit this phenomenon. Thus, longitudinal ribs should be added to optimize the PCHS‐LJ failure modes. Finally, solid finite element (FE) models of the test specimens were established in MSC. MARC. The analysis results are basically consistent with the experimental results. [ABSTRACT FROM AUTHOR]

An approach combining U-shaped dampers (USDs) and rocking walls is proposed in this paper to improve the seismic performance of traditional precast reinforced concrete (RC) frames with cladding panels (PRCFCPs): (1) the steel bar and USD connection methods are adopted at the top and bottom of the cladding panels to use the relative deformation between the cladding panels and the main structure and then dissipate the seismic energy and (2) rocking walls are added to the structure to control the structural deformation profiles. The USD numerical model is calibrated using the test data, and a series of nonlinear pushover analyses, dynamic time-history analyses, and incremental dynamic analyses are successively performed to compare the seismic performance and collapse capacity of the PRCFCP, PRCFCP with USDs (PRCFCP-USD), and PRCFCP with USDs and rocking walls (PRCFCP-USD-RW).The results show that the USDs in the PRCFCP-USD-RW undergo more uniform deformation along the structural height and higher energy dissipation efficiency and the PRCFCP-USD-RW exhibits enhanced seismic performance and collapse capacity, which verify the superiority of the proposed combined approach. [ABSTRACT FROM AUTHOR]

Precast concrete sandwich panels (PCSPs) have been extensively used as a facade wall in buildings to improve thermal efficiency. The connectors that link the two concrete wythes are mainly used for in-plane shear transfer. In this study, two cross-shaped glass-fibre-reinforced polymer connectors with different section areas are proposed, with the aim of achieving optimal performance and easy construction in PCSPs. First, the pull-out and shear capacities of the connectors were evaluated. Then four PCSPs and two reinforced concrete solid panel counterparts were fabricated and tested under out-of-plane static loads in order to evaluate their flexural behaviour. The parameters investigated included the connector section area and spacing. Moreover, two-dimensional finite-element (FE) analysis was conducted to reproduce the test. The results indicate that: (a) the proposed connectors can provide considerable performance in terms of anchorage and shear capacity; (b) the failure mode of the PCSP specimens was governed by connector failure; (c) the degree of composite action in terms of ultimate strength can be obviously enhanced by increasing the connector section area and/or reducing its spacing; and (d) based on a comparison with the test results, the proposed FE model can predict the flexural behaviour of the tested PCSPs. [ABSTRACT FROM AUTHOR]

• A new type of superimposed reinforced concrete shear wall with insulation is proposed by integrating the insulation panel into the precast exterior concrete panel to achieve both bearing and insulation capabilities. • The connection method of the longitudinal reinforcement at the horizontal joints of the superimposed reinforced concrete shear wall is indirect splicing on one side and direct splicing on the other side, and the direct splicing area is moved upwards to avoid the horizontal joints. A new type of superimposed reinforced concrete shear wall with insulation (SRCSWI) is proposed in this paper by integrating the insulation panel into the precast exterior concrete panel to achieve both bearing and insulation capabilities. Four full-sized specimens, including one cast-in-place reinforced concrete shear wall (CRCSW), two SRCSWIs and one superimposed reinforced concrete shear wall (SRCSW) without insulation, were designed for use in pseudo-static tests. The test results showed that the failure modes of the SRCSWIs were similar to those of the CRCSW and SRCSW. For the SRCSWI with a lower reinforcement ratio for the boundary elements, fewer cracks occurred in the wall, while the opening width of the cracks in the horizontal joints was relatively large, which means that the plastic deformation of this specimen was concentrated near the horizontal joints. For the SRCSWIs, the precast exterior concrete panel contributed little to the stiffness and carrying capacity of the walls. For the SRCSWI specimens, SRCSW specimen and CRCSW specimen with the same design axial load ratio, the stiffness, ductility and carrying capacity were basically consistent. For the SRCSWI specimen with a lower axial force, the carrying capacity was lower, but the ductility ratio and energy dissipation coefficient were higher than those of the other specimens. Finally, solid finite element (FE) models of the test specimens were established in ABAQUS and validated with the experimental results. The distribution of concrete damage, steel reinforcement stress distribution and hysteretic curves in the numerical analysis were basically consistent with the test results. [ABSTRACT FROM AUTHOR]