Experimental study on seismic performance of uncoupled and coupled steel plate shear wall with weak-axis connections
To study the seismic performance of uncoupled and coupled steel plate shear wall with weak-axis connections,three 1/3 scaled four-story specimens with weak-axis connections,including one uncoupled specimen and two coupled specimens,were designed.Then the quasi-static cyclic loading test was carried out.The failure mode,bearing capacity,stiffness degradation,ductility,energy consumption,column axial force and story drift,were compared and analyzed.The results show that regardless of whether it is coupled or not,the infill plate still resists shear through the tensile field,and finally tears along the edge,which leads to the in-span bending of the intermediate beam.Once the steel plates shear wall(SPSW)piers are coupled to be the coupled steel plate shear wall(CSPSW),the initial stiffness,bearing capacity,displacement ductility coefficient and energy consumption will be greatly improved by more than 65%,10%,40%and 14%,respectively.Strengthening the section stiffness of the coupling beam can reduce the stiffness difference of adjacent stories,thus avoiding the premature emergence of soft stories.However,if the cross-section of the coupling beam is set too large,the CSPSW will deviate from the theoretical expected failure mechanism,resulting in the underutilization of components.It is noted from the specimens'failure sequence that,the original two defense lines from infill plates to beam-column frame are transformed into three defense lines from infill plates to coupling beams then to beam-column frame,after the SPSWs are coupled to be the CSPSW.