Experimental study on CFRP-strengthened bolted splicing modular steel plate shear wall

The seismic performance of the steel plate shear wall (SPSW) structure will be weakened by the modular splicing of the infill steel plates. To address this, carbon fiber reinforced plastic (CFRP) was used to strengthen its splicing joints. First, the specimens of CFRP-strengthened bolted joints with different CFRP laying methods were tested in uniaxial tensile control, and the corresponding design method was proposed. Next, this method was introduced into the vertical splicing joints of modular SPSWs. Three 1/3-scale SPSW specimens, with and without CFRP-strengthened modular SPSW and complete SPSW, were tested under quasi-static cyclic loading. The failure modes and hysteresis performance of the three structures were compared, and the effects of using CFRP-strengthened splicing joints on various properties of the SPSW structure were investigated. The force mechanism of the CFRP-strengthened bolted splicing modular SPSW structure was further investigated by finite element (FE) analysis. The results indicated that the CFRP strengthening vertical splicing joints can effectively reduce the stress concentration around the hole walls of the infill steel plate, improve the performance loss of wall plates due to modular segmentation, and reduce slippage of splicing joints and out-of-plane deformation amplitude of wall plate. The CFRP-strengthened vertically bolted modular SPSWs increased the stiffness and load capacity of the structure, with yield bearing capacity and stiffness increased by 11.40% and 19.57% compared with those of the vertically bolted modular SPSW, respectively.