Experimental Study On A Seismic Reinforcement Element In Frame Structure

The aseismic reinforcement of the frame structure is mainly aimed at the old buildings with insufficient seismic fortification level and the buildings that have no serious damage after the earthquake and can be used normally after the reinforcement.This article selects the most commonly used cast-in-place joints and post-cast integral concrete joints on the existing concrete and steel frame beam-column joint connection methods,and the top and bottom angle steel frame beam-column joints are used to improve the connection design.The new reinforcement scheme of the frame structure.The reinforcement units used are defined as the concrete reinforcement substructure and the steel member reinforcement substructure connected by the rolled angle steel.This scheme can be used for the existing structures with insufficient seismic design.Reinforcement can also be applied to the repair and reinforcement of damaged structures after an earthquake.This article focuses on the quasi-static test and research on the proposed reinforcement unit to find the reinforcement unit to analyze its seismic performance.In the test,a set of cast-in-place concrete reinforcement sub-structure test pieces,a set of post-cast integral concrete reinforcement sub-structure test pieces,and three sets of rolled angle steel connection reinforced sub-structure test pieces were designed through low cycle The reciprocating loading test studies and analyzes the influence of different manufacturing methods and different loading systems on the seismic performance of strength,stiffness,hysteretic performance and energy dissipation capability.The results showed that:(1)Under the same low-cycle reciprocating loading system,the cast-in-place and post-injection specimens of the concrete reinforcement sub-members both obtain the typical arched hysteresis curve of the concrete member,and the hysteresis loops pinch together;the hadron component gets a full shuttle-shaped hysteresis curve;(2)Under different loading systems,the steel structure reinforcement sub-members connected by angle steel can obtain a full hysteresis curve,and under the maximum level of load displacement,the energy dissipation coefficient of the specimen is maintained at about 2.25,which is significantly higher Test piece for concrete reinforcement substructure;(3)The angle-connected steel structure reinforced sub-member will make its strength deterioration worse after experiencing a large displacement load,but it can still exhibit good hysteretic performance;(4)The angle-connected steel structure reinforcement sub-components can control the damage to be concentrated on the angle steel connectors,while the other components remain elastic,and the damage repair can be completed only by replacing the angle steel connectors.At the same time,Abaqus finite element analysis software was used to perform numerical simulation and parameter analysis on the reinforced substructure of the steel member connected by rolled angle steel,and analyze angle steel thickness and friction coefficient of the high strength bolts of the horizontal leg of the angle steel on the seismic performance of the structure.Simulation analysis results show that:The strength of this reinforcement structure is mainly provided by the angle steel connection.The thickness of the angle steel has an effect on the initial stiffness and ultimate strength of the test piece,especially the ultimate strength is more significant.In actual engineering design,the angle steel connection must be The thickness of the parts and the rigidity of the vertical members are reasonably designed.In order to explore the effect of the proposed reinforcement structure on the seismic performance of the frame structure,OpenSees software was used to simulate and analyze the reinforcement structure of the steel members connected by rolled angle steel.After verifying that the model can effectively simulate the performance of the reinforcement structure,the reinforcement structure is put into the frame system,and the dynamic time history analysis of the frame system before and after reinforcement is carried out to verify the reinforcement structure It can effectively limit the instantaneous maximum interlayer displacement angle and maximum residual interlayer displacement angle of the frame under earthquake action.