Pseudo-static Test Study On Multi-layer Semi-rigid Eccentrically Braced Planar Steel Frame

Compared with the traditional steel frame structure,the eccentrically braced steel frame not only has better lateral stiffness but also retains good structural ductility.In order to study the hysteretic performance and energy dissipation characteristics of eccentrically braced semi-rigid steel frames under low-cycle reciprocating loads,in this paper,a quasi-static test of a three-layer K-type eccentrically braced semi-rigid planar steel frame was conducted.And use the ABAQUS software to carry out finite element nonlinear analysis on a total of 8 models with three parameters that changed the link beam length,the link beam stiffener spacing and the vertical load on the frame.The main research is the damage form,hysteresis performance,stiffness degradation rate,ultimate bearing capacity,ductility and energy dissipation capacity of this structural system.The test results show that the eccentrically braced semi-rigid steel frame has better deformation energy dissipation capacity and seismic performance.Compared with the test results,the simulation results of the finite element model with the same test parameters are in good agreement in terms of failure form,hysteresis performance,stiffness degradation,ultimate bearing capacity,ductility coefficient and energy dissipation capacity.Practice has proved that it is feasible to use ABAQUS to simulate this method.The hysteresis curve of the specimen showed a certain "pinching" phenomenon.With the increase of the length of the link beam,the ultimate bearing capacity and energy-dissipation capacity of the frame show a downward trend,and the phenomenon of pinching of the hysteresis curve increases.The vertical load on the frame and the parameter changes of the web stiffener spacing of the link beam have little effect on the hysteresis curve,the ultimate bearing capacity of the frame and the energy dissipation capacity.Finally,according to the results of experimental research and finite element analysis,the seismic performance of the multi-layer K-shaped semi-rigid eccentrically braced steel frame is obtained,which provides a reference for the seismic design of the semi-rigid eccentrically braced steel frame and has certain practical significance in engineering.