| For high-rise buildings or super high-rise buildings,shear walls are important lateral force resisting members because of their large self weight and lateral stiffness.However,under the action of strong earthquake load,the seismic response of shear wall members is severe,and once damaged,it is difficult to repair.Although the ordinary reinforced concrete shear wall may not collapse after the earthquake,it will lose the value of repair due to the large residual deformation.Therefore,ordinary reinforced concrete shear wall has some limitations in economic and seismic performance.In recent years,with the continuous development of structural seismic design theory,the requirements of seismic design are gradually improved,and the structural seismic technology is developing to the restorable functional structure.In order to improve the seismic performance of shear walls,an external magnetorheological damper(MRD)is proposed In this paper,the seismic performance of high-strength reinforced concrete shear wall with external MRD is analyzed by numerical simulation,and the influence of installation height and output of MRD on the seismic performance is discussed and studied.Finally,the results are calculated by theoretical analysis The main failure modes and normal section bearing capacity of shear wall are analyzed.The main research contents are as follows:(1)Based on the finite element software ABAQUS,the hysteretic behavior of high-strength reinforced concrete shear wall with external MRD is analyzed.Several equivalent simulation methods of bond slip between steel and concrete are compared,and the selection of different parameters and calculation methods in the concrete plastic damage model(CDP model)are compared.The results show that using clough constitutive stiffness weakening restoring force model as reinforcement constitutive model,the stress-strain relationship of concrete is calculated according to appendix C.2 of code for design of concrete structures,the value of concrete damage factor is between 0.90 and 0.95,and the compression damage recovery coefficient is 0.8.Choosing the above constitutive parameters can accurately predict the seismic performance of cfrpsw members.(2)Based on the test of high strength reinforced concrete shear wall with external MRD under low cycle cyclic loading,three numerical models of shear wall(CFRPSW、CFRPSW+MRD、SSW+MRD)are established by using the verified constitutive parameters.Under low cycle cyclic loading,the hysteretic curve,skeleton curve,stiffness degradation curve,strength degradation curve,energy dissipation capacity and damage cloud of shear wall are analyzed The results are compared with the experimental results.The results show that: the finite element software ABAQUS and the model can well simulate the stress change and failure mode of shear wall in the whole loading process,which can be used for further simulation analysis.(3)Parametric analysis is carried out on the key factors affecting the seismic performance of high-strength reinforced concrete shear wall with external MRD,such as installation height and output.The results show that: with the increase of MRD installation height and damping force,the energy dissipation capacity and bearing capacity of shear wall are increased,and the seismic performance is effectively improved.(4)The failure mode and normal section bearing capacity of high-strength reinforced concrete shear wall are studied by theoretical analysis method,and the results are compared with the test and finite element calculation results.The results show that the theoretical and experimental results are in good agreement,which can play a certain reference role in the prediction of failure mode and the calculation of bearing capacity of high-strength reinforced concrete shear wall. |
