Experimental Study On The Seismic Behavior Of CFRP-reinforced Concrete Shear Wall

The shear wall structure has become the main lateral force resisting member of the high-rise building because of its excellent carrying capacity and seismic behavior. But with the development of the high-rise building, the requirements for seismic behavior of shear wall have exigent.For a long time,the shear wall met the requirements of the existing design code has excellent deformation capacity.The shear wall produce sufficient deformation under earthquake to increase earthquake resistance capacity of structure. It is inevitable that the traditional reinforced concrete shear wall has great residual deformation after the earthquake because of elastic-plastic of the reinforcement.So it is necessary to further improve the seismic behavior of shear wall,reduce the residual deformation of shear walls, improve the mechanical behavior of the structure after earthquake,and ensure the shear wall has the ability to recover the function. Carbon fiber reinforced polymer(CFRP) bar is an advanced composite material.Unlike the reinforcement,FRP bars have no plastic deformation before reaching its ultimate tensile strength. Its stress-strain relationship is linear elastic. It is due to the linear elastic property of FRP bars, FRP bars are expected to be used to control the residual deformation of the seismic structure.Based on the experimental results of five shear walls(one totally reinforced with steel bars,and the other four partly or totally reinforced by CFRP bars in the longitudinal direction) under quasistatic cyclic loading,the seismic behaviors and residual deformation of shear walls reinforced by CFRP bars were studied.The conclusion as follows :(1)All specimens have reached high flexual strength, which demonstrated that ultimate bearing capacity could be met though reasonable configuration of CFRP bars in shear walls.And walls using CFRP bars exhibits its effectiveness in resisting lateral force.(2)Compared with RCSW-1,the cracks of shear walls reinforced by CFRP bars are widely distributed interval between the adjacent cracks became closer as well. That shows it could improve the pattern of the crack distribution of shear walls when reinforced with CFRP bars. what’s more, it could also prevent the appearance of big cracks due to the excessive plastic deformation of steel bars.(3) It could be found that a certain number of rational allocation of CFRP bars in the shear wall can effectively control the crack width.(4) The greatest advantage of using steel reinforcement in shear walls is having higher energy dissipation through inelastic deformation. In contrast, the greatest advantage of CFRP reinforced is no large residual deformation and cracks in addition to reaching ultimate bearing capacity and reasonable energy dissipation level.