Seismic Performance Of Fabricated Shear Walls Connected By Energy-dissipating Mild Steel

Prefabricated shear wall structures are widely used in residential buildings.The mechanical properties of prefabricated shear wall structures depend on the seam setting and connection quality.In our country,the assembled shear wall is usually connected by cast-in-situ concrete,but it is difficult to be repaired due to its damage and energy dissipation under earthquake load.At the same time,it can effectively reduce the damage of shear wall and improve the deformation capacity and energy dissipation capacity of the assembled shear wall structure.In order to obtain the better performance and convenient installation of the assembled shear wall structure connected by energy dissipated mild steel,this paper studies the influence of the opening direction,installation mode and coupling ratio of energy dissipated mild steel damper on the seismic performance of the structure by ABAQUS finite element analysis and theoretical analysis.The main work and conclusions are as follows:(1)Conduct material constitutive selection and parameter research.In order to verify the reliability of material constitutive parameters,the finite element model of shear wall is established by using ABAQUS software.The results show that the bearing capacity,ductility coefficient and failure mode of the FEM model are similar to those of the test specimens,and the above parameters are reasonable and reliable.It lays a foundation for establishing the finite element model with good convergence and reliability in the future.(2)A new type of double-X mild steel damper with open slot is proposed.The mechanical properties of the damper are compared by finite element analysis.The results show that the damper has good energy dissipation capacity and better bearing capacity and deformation capacity than the vertical slot damper.On this basis,the finite element model of assembled shear wall with dampers with different slots directions is established.The results show that the shear wall with transverse slot damper has higher bearing capacity,and the deformation capacity and energy dissipation capacity are better when the damper thickness is smaller.(3)In order to simplify the installation mode of dampers,the frictional highstrength bolts are proposed to connect the dampers and shear walls.The bearing capacity of this new installation mode is designed,and two finite element models of shear wall with traditional installation mode and two with new installation mode are established.Compared with the traditional installation method,the deformation capacity of the shear wall model using the new installation method is reduced slightly,and the bearing capacity and energy dissipation capacity are almost the same,which is reliable and easy to install.(4)Based on the continuous rod method,the prefabricated shear wall structure connected by energy-dissipating mild steel is theoretically analyzed.At the same time,8 groups of shear wall specimens with different coupling ratios are established by controlling the thickness of the damper and the opening direction.Range of suitable coupling ratios for fabricated shear wall structures with steel connections.The analysis results are as follows: it is recommended that the coupling ratio of the fabricated shear wall with transverse joint damper should be set in the range of 0.15 to 0.3,and when the coupling ratio is set to 0.15,better seismic performance and optimal economic performance can be obtained;it is recommended to use vertical joints.The coupling ratio range of the assembled shear wall of the damper is 0.2～0.35,and the performance is better when the coupling ratio is 0.2.