Study On Seismic Behavior Of Shear Wall With New Coupling Beam

Under earthquake action,the coupling beam in shear wall structure is the key energy dissipation component.After reasonable design,it can make the coupling beam yield before the shear wall,enter the plastic to consume a large amount of seismic energy,play the role of protecting the shear wall and reducing the damage of the main structure.However,the coupling beams are often severely damaged in earthquakes,and it is difficult to repair them after earthquakes.Moreover,the coupling beams generally have small span-height ratio and are prone to brittle failure.Therefore,the search for a new type of coupling beam with good energy dissipation effect and easy post-earthquake repair has become the focus of attention of many researchers.This paper is based on an improved triangular steel plate damper which can be used in coupling beams.The main research contents and conclusions are as follows:(1)The design principle of the damper is studied,which shows that the damper should satisfy the following three principles: 1)the ultimate bearing capacity of the damper should be less than the yield bearing capacity of the concrete beam;2)the yield bearing capacity of the damper should not be too low;3)the ultimate deformation of the damper should satisfy the requirements of the damper under large earthquakes Displacement.The structure of the damper and the coupling beam is put forward.The connection mode of the damper and the coupling beam should be end plate-shear key,the embedded end plate should be anchored reliably,and the longitudinal reinforcement at the break of the coupling beam should be welded to the embedded end plate.Through the above research,a new type of shear wall specimen with the damper installed in the coupling beam is designed.(2)The quasi-static test was carried out to study the seismic performance of coupled shear walls with improved triangular steel plate dampers installed in the coupling beams,and the results were compared with those without dampers.The results show that the energy dissipation capacity and deformation capacity of the new coupling beams are obviously better than those of the traditional ones,and the stiffness and strength degradation of the new coupling beams are less than those of the traditional ones.The deformations and energy dissipation of the new coupling beams are concentrated in dampers,which reduces the damage of the concrete coupling beams and is conducive to post-earthquake repair.(3)Based on the quasi-static test,ABAQUS is used to simulate the damper and the new coupling beam structure.The results show that the restoring force model of the damper can be simplified to a bilinear model,the damper is strengthened under reciprocating load,and the overstrength factor can be 2.4.The finite element model used in this paper can well simulate the bearing capacity,stiffness and yield failure of the specimens in the test.The bad mechanism and the “kneading” effect prove the validity of the finite element model in this paper.