Research On Hysteretic Behavior About Semi-rigid Connection In Steel Frame-SRC Structure

In present stage, the rigid connection was widely used. This connection which wasmade by groove weld and the bolt is likeiy to brittle fracture in moderate earthquake.But semi-rigid connection performed better capability in deformation and energydissipation which can resist dynamic loads. Beam-to-column connection is veryimportant and complicated content in the steel frame design, especially, Doubleweb-angle and top-seat-angle connection is a typical semi-rigid connection, whichhysteretic curve is full. But it is hard to establish analytical formula.The first, factors analysis are conducted on the experiment results. In this paper3-Dnonlinear finite precise numerical simulation experiment had been done for the doubleweb-angle and top-seat-angle connection. This analysis is used the popular FEMsoftware ABAQUS. The P curves and the hysteretic curve are obtained with theFEM model considering material and geometrical and state nonlinearity. The effectsof the thickness of concrete cover, concrete rank, the friction coefficient, the anglelength, the angle thickness, the bolt diameter and grade on strength, the bolt prestress,steel grade and the gauge distance from the edge of the angle to the center of bolt lineon strength and hysteretic behavior of connections were studied. Finite element resultsreveal that the hysteretic behavior, initial stiffness and load bearing capacity aresignificantly affected by the thickness of concrete cover, the gauge distance from theedge of the angle to the center of bolt line, the angle length, the angle thickness andthe bolt diameter and grade.Many scholars have studies with hysteretic performance of semi-rigid connectionsat home and abroad. Some simplified hysteretic models have been proposed.According to the results of the finite element analysis of double web-angle andtop-seat-angle connection hysteretic curves, this paper put forward a new simplifiedhysteretic model.In this paper, different high of building with semi-rigid connection were studied.Displacement and acceleration time history curve are obtained under different seismicwave motivation. The results reveal that the bending moment in the end of semi-rigidconnection is reducing and the bending moment in midspan is enhanced; the naturalperiod, displacement, corner in the interlayer of semi-rigid connection is larger thanrigid connection, meanwhile, the acceleration amplification factor of semi-figid connection is reduced.