Study On Seismic Behavior Of Assembled Coupled Shear Wall With Arch Coupling Beam

Coupled shear wall structures are widely used in tall building structures due to their high bearing capacity and lateral stiffness,in which the coupling beam should have good connection function and energy dissipation capacity.On the basis of literature research,this paper proposes a new type of prefabricated coupled shear wall with arch coupling beam,which is composed of prefabricated wall limb,prefabricated arch coupling beam,composite layer,section steel vertical connector and shear steel plate.The main research contents include:Firstly,the structural design and assembly construction scheme of the new shear wall are discussed.In order to study the seismic performance of the joint,the quasi-static test was carried out on the assembled arch coupling beam joint,and the destruction form,hysteretic curve and energy dissipation capacity were obtained.On the basis of experimental research,finite element software was used to establish the model of cast-inplace coupled shear wall joint and the model of assembled coupled shear wall joint with arch coupling beam respectively,and the stress performance and destruction form of the two types of joints were compared through finite element analysis.Based on the analysis and experimental research of joints,the finite element comparative analysis of two-storey cast-in-place coupled shear wall and assembled coupled shear wall with arch coupling beam was carried out,and the seismic performance parameters including hysteretic curve,skeleton curve,stiffness degradation curve,ductility coefficient and energy dissipation capacity were obtained.The coupling ratios of yield points,limit points and failure points were obtained respectively to evaluate the contribution of arch coupling beam to energy dissipation capacity and seismic performance of coupled shear wall.Under different concrete strength or different axial compression ratio,the seismic performance of assembled coupled shear wall with arch coupling beam is compared and analyzed.The main conclusions are as follows:The proposed new type of prefabricated coupled shear wall with arch coupling beam can improve the efficiency of construction through proper structural design.The quasistatic test of the assembled arch coupling beam joint shows that the arch coupling beam can effectively avoid the destruction of the coupling beam concentrated at the end of the coupling beam,and the cracks are evenly distributed along the span direction of the coupling beam.Also the shear plate is set at the end of coupling beam to fully bear the force,which can effectively improve the shear bearing capacity of the end of the coupling beam.The vertical section steel connectors is set in the wall limbs,which can effectively connect the wall without slipping at the construction joint.Through the finite element analysis,the stress performance of this new type of prefabricated joint and the cast-inplace joint are analyzed.The bearing capacity of this two joints is similar,but the ductility of the prefabricated joints is greatly improved.And the destruction form of coupling beam is changed by arch coupling beam,section steel and shear steel plate,making the destruction area spread from the end of coupling beam to the whole coupling beam,which conform to the design concept of "strong joint and weak coupling beam".By comparing the prefabricated coupled shear wall with the arch coupling beam and the cast-in-place coupled shear wall,the stress of the rebar at the end of coupling beam in cast-in-place shear wall increases rapidly after the rebar yields.After reaching the ultimate strength,the coupled beam loses its function and the coupling ratio descends significantly.At this time,most of the load of the coupled shear wall is borne by the wall limb.The stress of the rebar of coupling beam in the prefabricated coupled shear wall increases slowly in the yield and hardening stage.And in the whole process of destruction,the rebar of coupling beam shows good coupling effect,which delays the destruction of the wall limb and improves the ductility of the whole structure.Through comparative analysis,when the axial compression ratio of the assembled coupled shear wall with arch coupling beam is larger,the bearing capacity of the assembled coupled shear wall with arch coupling beam is larger,but the ductility of the assembled coupled shear wall with arch coupling beam is lower.When the axial compression ratio is greater than 0.3,the ductility decreases significantly.Increasing the concrete strength can improve the bearing capacity of the coupled shear wall.But when the concrete strength is greater than C40,the ductility decreases obviously.