Analysis Of The Joints Of The Welded Side Plates Of Steel Frames And The Mechanism Of The Continuous Collapse Resistance

In recent years,with the frequent occurrence of terrorism and accidents,buildings have continuously collapsed,so the problem of continuous collapse of buildings has attracted more and more attention.From the perspective of prevention,the welded side plate wing-type node can avoid continuous collapse as much as possible,which has strong application value.In this study,numerical simulations are used to illustrate the ability of the welded side slab flared joint and the steel frame structure to resist continuous collapse from the perspective of the joint and the whole.The finite element software is used to construct the ordinary joint and the welded slab flared joint.The model analyzes the mechanical properties under low-cycle cyclic loading.The catenary effect and resistance to continuous collapse are analyzed by a two-span single-column node model.In addition,the standby static load path method was adopted for the vertical plane steel frame structure.The nonlinear static analysis and nonlinear dynamic analysis were carried out,and the following conclusions are drawn:?1?The low-cycle reciprocating loading of the finite element model has verified the validity of the model.Both the finite element results and the experimental results agree that the side plate wing-type joint can effectively move the plastic hinge outward.From the perspectives of stress distribution,hysteresis curve,skeleton curve,etc.It has been quantitatively demonstrated that the side plate wing-type joint has better ductility and energy consumption compared to ordinary joints,improves the mechanical performance of components,and the ability to undergo large deformation.The ability is also stronger,which provides a guarantee for better exerting the catenary effect.?2?By analyzing the catenary effect and anti-continuous collapse of the side plate winged joints,it is found that the catenary effect of the side plate winged joints can better play the catenary effect and improve the ability to resist continuous collapse At the same time,the mechanism of catenary resistance is calculated and analyzed;the values of steel strength,side plate length l₁,and side plate width b_s are suggested through parameter analysis.Finally,the contribution of catenary effect to continuous collapse is evaluated.?3?The nonlinear static analysis and nonlinear dynamic analysis were performed on the two joint plane frames by finite element software.The results consistently show that the steel frame in the form of side-panel wing joints is compared with the steel in the form of ordinary joints.The frame can better play the catenary effect and show good plasticity and bearing capacity,which improves the structure's resistance to continuous collapse.In addition,the failure of two kinds of joints in the plane steel frame side column is more harmful to the continuous collapse resistance of the structure.