Research On Seismic Performance Of Steel Frame Structure With Reinforced Side Plate At Beam-end

Low alloy steel not only has the advantages of good comprehensive performance,low temperature performance,cold stamping performance,welding performance and machinability,but also can reduce the weight of the structure,save steel and prolong the service life.Widely used in bridge engineering,vehicle engineering,ship engineering,construction engineering,pressure vessels,etc.The performance of the beam-column joints in steel frame is very important to the overall performance of the structure.The new ductile joints can improve the mechanical performance of the traditional steel frame joints,and the seismic performance of the new ductile joints needs to be further studied.Based on experimental research and numerical simulation,this paper analyzes the force of side plate reinforced joints and side plate reinforced steel frames successively.The main research is as follows:（1）Study on the performance of joint plate:12 Q345B steel joint plate specimens were tested in unidirectional tension and tension and compression cycles.At the same time,a three-dimensional nonlinear finite element analysis model was established and the finite element analysis was carried out,and the load-displacement curve and failure mode were studied.By comparing the test results with the finite element results,the validity of the nonlinear finite element model is verified,which lays a foundation for the subsequent finite element analysis of steel frame beam-column joints.（2）Analysis of beam-column joints of side plate reinforced steel frame:In this paper,the hysteretic behavior of ordinary type and side plate reinforced steel frame beam-to-column joints under low cyclic loading is experimentalized.The three-dimensional nonlinear finite element analysis of the two types of joints is established and carried out.The ultimate bearing capacity,ductility coefficient,energy dissipation and equivalent damping coefficient are studied in depth.The key parameters of the beam-column joints of the reinforced steel frame with side plates are optimized.The results show that the ultimate bearing capacity,ductility coefficient,energy dissipation value and equivalent viscous damping coefficient of the reinforced joints are increased by 30.8%,51.2%,108.44%and 13.5%,respectively,compared with those of the ordinary joints.After analysis,it is suggested to strengthen the side plate parameter La and take 0.4～0.8 times of flange width;The width C of the side plate is 0.2-0.33 times of the flange width.（3）The steel structure seismic performance analysis framework,based on the lateral plate reinforced beam-column node analysis,design and set up three layer two cross beam end side panel reinforced with ordinary steel frame finite element model,studied the hysteretic performance,two kinds of model beam end sides strengthen steel frame plastic hinge than ordinary steel frame out a 195 mm,and the energy dissipation is better.In addition,the ultimate bearing capacity,energy dissipation capacity and equivalent viscous damping coefficient of the beam-end and side-plate reinforced steel frames are increased by 12.13%,71.2%and 23.8%,respectively,compared with the ordinary steel frames.