Seismic Performance Analysis Of Damping Infilled Frames Based On Separation Modeling

Research on the damage of infill wall frame structure in earthquake disasters over the years shows that due to excessive lateral stiffness and excessive mutual restraint with the frame,the infill wall often suffers serious damage before the main frame of the frame.It is difficult to improve the seismic performance of masonry infill walls in reinforced concrete frames.The damping infill wall weakens the stiffness of the wall due to the existence of the viscoelastic layer,and dissipates the seismic energy through its shear hysteretic deformation.Based on the existing research,this paper studies the influence of viscoelastic layer and partitioning method on the seismic performance of damping infill walls.The main research results are as follows:(1)Compare the finite element models of the infill wall frame structure,summarize the characteristics of each model,and select the suitable finite element model for this paper.Based on the existing experiments,establish the finite element model corresponding to the experiment,and verify the rationality of the modeling method.The bearing capacity and stiffness characteristics of empty frame,ordinary infill wall and damping infill wall are compared and analyzed.It is found that damping infill wall can improve the mechanical performance of ordinary infill wall,and the addition of viscoelastic material reduces the high stress distribution of masonry infill wall area.(2)On the basis of verifying the correctness of the modeling method,the separation models of the two-zone,three-zone,and four-zone infill walls were established respectively.The influence of the viscoelastic layer on the bearing capacity,stiffness characteristics and viscous damping coefficient of the damping infill walls was studied.The elastic modulus is the main influencing factor.The suggested values for the thickness and elastic modulus of the viscoelastic layer are given.(3)For the two-span frame structure,the separation models of the structure forms of the empty frame,the ordinary infill wall frame,the two-zone infill wall frame,the three-zone infill wall frame and the four-zone infill wall frame were established respectively,and the ordinary infill wall and partition were compared and analyzed.According to the different failure forms of the infill wall,the influence of the partition method on the bearing capacity and stiffness characteristics of the two-span frame structure was studied,and it was confirmed again that the addition of the viscoelastic material layer can achieve the purpose of weakening the structural stiffness.Similarly,the greater the number of sub-zones,the smaller the stiffness of the structure and the larger the yield displacement.(4)According to the results of finite element analysis,combined with theoretical analysis,a formula for calculating the lateral stiffness of partitioned infill walls is proposed.