Nonlinear Finite Element Simulation Of Infilled Masonry Walls With Flexible Connections

In recent years,earthquakes occurred frequently at home and abroad.After a large number of earthquake damage investigations,the disasters caused by the destruction of masonry filled walls in earthquakes are extremely common,and the reasons are investigated.The connection between infilled walls and frames accounts for a large proportion.Based on ABAQUS finite element analysis software,the modeling method of frame masonry infilled wall with flexible connection is studied in this paper,and the nonlinear finite element analysis model of frame masonry infilled wall structure is established.The model is used to simulate the failure process of frame masonry infilled wall in and out of the plane.The main contents and conclusions of this paper are as follows:(1)This paper summarizes the current design specifications and the construction methods of flexible connections proposed by various experts,and compares and analyzes the advantages and disadvantages of different construction methods of flexible connections between infilled walls and frames.The mechanical behavior of infilled wall frame structure outside the plane when flexible connection is adopted,and the way that scholars deal with the connection part between infilled wall and frame in finite element modeling.(2)The design content and design method of flexible connections are theoretically analyzed,and the joint width of infilled wall and frame beam and column is determined according to the purpose of joint design of flexible connection.This paper introduces the action of vertical and transverse tension tendons and their effects on the mechanical properties of filled walls,analyzes the action mechanism of tension tendons in combination with the theory of structural mechanics,and further expounds the influence of the spacing between tension bars and tendons.(3)A model of infilled wall frame with flexible connection between infilled wall and frame is established,in which the in-plane and out-of-plane mechanical properties of infilled wall can be analyzed at the same time.In this paper,the in-plane behavior of the infilled wall structure with flexible connections under a reciprocating load in a plane is fitted.On the condition of flexible connection under an out-of-plane load,the reliability of the proposed modeling method is verified by fitting the out-of-plane mechanical behavior of the infilled wall frame structure.(4)with the help of the frame infilled wall model established under the monotone load outside the plane,by changing the stiffness value of the spring element in the model,the influence of the connection stiffness between the infilled wall and the frame on the out-of-plane mechanical behavior of the structure is analyzed.A more suitable connection stiffness value is obtained.At the same time,by comparing the test results with the calculated results of the specimens with different connection construction methods,a better structural mode of the wall is obtained,in which the mechanical properties of the wall outside the plane are better.