Research On Key Technologies Of Precast Cavity Energy Dissipation Shear Wall

According to the construction industry development trend in China,precast concrete construction will be a new direction,how to improve the safety of precast concrete structures under earthquake excitation has become an urgent task to be solved.In order to reduce the structure weight and improve the seismic performance of conventional shear wall,a novel precast cavity energy dissipation shear wall was proposed,which was a shear wall with through cavity and oblique energy dissipation reinforcements arranged inside,and the horizontal joints of the wall are keyway-type.A series of research work has been done for two key technologies of cavity energy dissipation shear wall and keyway-type horizontal joints.The main research contents and results are as follows:(1)Firstly,Cavity energy dissipation shear wall,cavity shear wall and conventional reinforced shear wall were tested under static loadings and reserved loadings using finite element software ABAQUS.Then,comparative analysis of the three types shear walls was carried out.Finally,the formula for estimating the horizontal ultimate bearing capacity of cavity energy dissipation shear wall was proposed based on the theoretical analysis.The research results indicate that,setting a cavity in the shear wall could improve the structural ductility performance of the shear wall.Compared with the conventional shear wall,the displacement ductility ratio of cavity energy dissipation shear wall could improve 10%,and energy dissipation capacity of cavity energy dissipation shear wall were two times larger than those of the conventional shear wall.The errors between the theoretical and simulation results of the horizontal ultimate bearing capacity of cavity energy dissipation shear walls are within 10%,which could meet the requirement of engineering estimation.(2)In this paper,the shear tests of conventional horizontal joint and keyway-type horizontal joint were carried out.On this basis,shear mechanism of keyway-type horizontal joint and the influence of keyway structure on the performance of horizontal joint were analyzed.In addition,the shear capacity of the keyway-type horizontal joint was calculated and compared with the test results.The research results indicate that,setting keyway could improve the shear strength and deformation capacity of horizontal joint.Compared with conventional horizontal joint,the ultimate bearing capacity of keyway-type horizontal joint was increased by about 9% to 17%.The shear capacity of keyway-type horizontal joint was composed of five parts: the shear capacity of concrete interface,keyway,dowel action,pressure and shear friction effect.The form of keyway would affect the shear capacity of horizontal joint.The inclined angle of keyway should be 60 °?45 °,and the keyway should not be too low.The current domestic standards were conservative in calculating the shear capacity of keyway-type horizontal joint.The Canadian code in the overseas code was more accurate for the calculation of the keyway-type horizontal joint.The calculation method for the alveolar type connection was not applicable to the keyway-type horizontal joint in this paper.