Finite Element Analysis on Seismic Performance of Tubular Web Reduced Section Connection

Abstract

In order to avoid the brittle failure of the weld at the beam and column interface, a new type of prefabricated joint with tubular web reduced section connection (PTWRBS) between concrete-filled square steel tubular column and steel beam was proposed, so that move plastic hinge outward from the contact area of beam and column under earthquake action and be repaired and strengthened rapidly after earthquake. Numerical models of this new joint were established by using the finite element software ABAQUS and validated by test data. The finite element models were used to analyse the mechanical property of the joint under cyclic loading. The load-carrying capacity, hysteretic behaviour and failure mode were compared, and the influence of the thickness of cantilever beam flange, the number of high strength bolts, the widened width of cantilever beam flange and the weakening length of the tubular web beam flange on the seismic behaviour of PTWRBS. The research results showed that the energy dissipation of the joints under earthquake is mainly achieved through the plastic deformation of the tubular web beam section and the friction slip of the high-strength bolted area. The failure mode of the joint is local buckling in the plane of the tubular web beam segment, which realizes the plastic hinge outward from cantilever beam. In the design of the joint, parameters such as the thickness of cantilever beam flange, the number of connecting bolts, the widened width of cantilever beam flange and the weakening length of tubular web beam section flange should be taken into comprehensive consideration and selected reasonably, so as to the transfer of plastic hinge under earthquake action and the rehabilitation of the joint after earthquake could be achieved.