Study On Seismic Behavior Of L-shaped Prefabricated Shear Wall With Energy Dissipation Joints

In precast concrete shear wall,the connection performance of component splicing joint surface directly affects the bearing capacity and deformation capacity of shear wall members and even the whole structure,at present,the joint connection in our country is based on the wet joint to realize the rigid connection.Based on the design concept of "strong horizontal joint,weak vertical joint",this paper proposes a kind of L-shaped prefabricated shear wall with energy dissipation vertical joint,the mild steel dampers are placed in the vertical joint to connect wall limbs to form a "semi dry structure",the dampers are used to provide the initial stiffness under small earthquakes and dissipate energy under large earthquakes.In order to study the seismic performance of the new energy dissipation shear wall,quasi-static tests were carried out,the main research contents are as follows:1)Three L-shaped prefabricated shear wall specimens with energy dissipation vertical joints were designed.The low cycle cyclic quasi-static test was carried out to study the seismic performance of the specimens under different axial compression ratio,reinforcement ratio and concrete strength.The results show that the failure modes of the three specimens are bending shear failure of web wall and bending failure of wing wall;with the increase of axial compression ratio,reinforcement ratio and concrete strength,the bearing capacity and overall stiffness of the specimens are improved,the deformation capacity and energy dissipation capacity are reduced,but the displacement ductility coefficient could reach more than 3,the maximum value is 4.07,and the ultimate displacement angle was more than 2times of the elastic-plastic displacement angle limit of 1/120 specified in the code;in the test,no out of plane deformation was found in the dampers,which realized the overall working stability of the new shear wall and dissipated energy before the yield of the wall,so as to protect the wall.2)The reinforcement design and fabrication of CFRP sheets were carried out on three damaged L-shaped prefabricated shear walls with energy dissipation vertical joints,the low cycle reciprocating quasi-static test was carried out,the bearing capacity,deformation capacity and energy dissipation capacity of the three strengthened specimens are analyzed.The results show that after strengthening,the bearing capacity,displacement ductility coefficient and initial stiffness of the three specimens are reduced,but they can meet the requirements of the code for the bearing capacity and deformation capacity of the shear wall specimens,the energy dissipation capacity is increased.Figure 34;Table 13;Reference 56...