Study On Seismic Performance And Design Method Of Three-Section Replaceable Energy-Dissipating Beam

The traditional seismic design mainly focuses on the prevention of structural collapse and the protection of people’s lives,and often ignores the post-earthquake repair of buildings and the restoration of social order.Based on the idea of earthquake resilient structure,the RCS hybrid frame structure with replacement members is proposed.Under earthquake action,the damage is concentrated in the energy-dissipated link,and the structural function can be quickly restored by replacing the damaged link.In this paper,a three-section replaceable energy-dissipating beam is proposed.The energy dissipation beam is divided into three sections,including the non-energy dissipation beam at both ends and the replaceable energy-dissipating link in the middle.The seismic performance and replaceable performance of the three-section energy-dissipating beam are systematically studied by experiments,finite element numerical simulations and theoretical analysis.The main contents and conclusions are as follows:The replaceability and the seismic performance of three-stage replaceable energy-dissipated beam are studied by pseudo static test.The test includes 10 specimens.The test parameters include the web type of replaceable energy-consuming link,the type of web steel and the connection between the replaceable energy-consuming link and the non-energy consuming beam.The results show that the force-displacement hysteresis curve of each specimen is full,showing excellent energy consumption and deformation capacity;the web can improve the specimen by using low yield point steel or corrugated steel.The ultimate plastic angle of the three-stage replaceable energy consuming beam is about 0.1rad,and the mean value of the super strength coefficient is1.72,which is greater than the limit values of 0.08 rad and 1.5 specified in AISC341-16;when the end plate or double channel steel is used to connect the replaceable energy consuming beam section with the non-energy consuming beam section,the three-stage replaceable energy consumption beam has good replaceability.Thirteen three-section replaceable energy-dissipated link models are established by ABAQUS finite element software,and the effects of length coefficient of replaceable link,web height thickness ratio and shear capacity ratio of beam section on the seismic performance of three section replaceable energy dissipation beam are analyzed.The results show that with the increase of length coefficient of the middle energy-dissipated link,its energy dissipation capacity decreases and the shear bearing capacity and deformation capacity also decrease,and it is suggested that the value of the middle energy-dissipated link is between 0.8 and 1.2;with the decrease of the height thickness ratio of the web,the cumulative energy consumption of the energy-dissipating link increases,but the overstrength coefficient and deformation capacity of the three-section replaceable energy dissipation beam decrease;When 1.17≤α≤1.46,the energy dissipation mechanism of three-section energy-dissipating beam will change to the energy dissipation mechanism of multi-stage energy-dissipating beam,that is,the web of energy-dissipated link will yield,and the non-energy dissipation beam will also yield.Based on the capacity design method,the bearing capacity calculation formulas of the middle replaceable energy-dissipated link and the non-energy dissipation beam are proposed,and the reasonable structural measures of the middle replaceable energy-dissipated link are given.In order to satisfy the replaceability of the damaged link,the end plate connection and double channel connection are recommended,and the design method is given.On this basis,the design process of three-section replaceable energy-dissipating beam is further proposed.