The Seismic Performance Analysis Of The Steel Staggered Truss Structure With Eccentric Buckling-Restrained Braces

The research of steel staggered truss structure system has become something of an engineering and academic circles in China and abroad in recent years,the system uses a plane truss system,it has the advantages of high lateral stiffness,light weight,quick construction speed,low cost and environmentally friendly.Most of the research in China and abroad are bearing and force transmission way and using the finite element analysis and experimental analysis studied the horizontal seismic performance and some related influencing factors,but the longitudinal lateral stiffness is smaller than the horizontal lateral stiffness of the steel staggered truss system,it is not conducive to the overall seismic capacity of the structure system,so reasonable and appropriate longitudinal lateral stiffness compared with horizontal lateral stiffness are equally important,it is the one of the important link of the overall seismic capacity,but have done little research in China and abroad.This paper based on this problem,referenced domestic and foreign existing related specification and predecessors' research results,used the finite element analysis software SAP2000,established the staggered steel truss structure model.Set the eccentric buckling restrained braces in the longitudinal of steel staggered truss structure,the purpose is to increase the longitudinal lateral stiffness and to strengthen the structure of the seismic ability.This paper uses the finite element analysis software SAP2000 establishing staggered truss structure,the structures with two different forms of eccentric support in the longitudinal,and the structure with the eccentric buckling restrained braces in the longitudinal.First,modal analysis of the modal are conducted to comparison and analysis their basic dynamic characteristic.Then response spectrum method and elastic time-history analysis under frequent earthquakes are conducted on the modal of the original structure,traditional eccentric support structure and the eccentric bucklilng restrained braces structure,to analysis the seismic response parameters.Finally,the elaslic-plastic time-history analysis are completed on the modal of the traditional eccentric support structure and the eccentric buckling restrained braces structure,to comparison and analysis the seismic response under severe earthquake.The results of the analysis shows:Reasonable arrangement of support is more effective to improve the structure stiffness;In the elastic stage,the stiffness of the structure is increased obviously and the earthquake reaction is obviously reduced after added support,but the the eccentric buckling restrained braces and the energy beam section have not yet to produce plastic deformation,and did not play a role of energy consumption,so the eccentric buckling restrained braces and the Traditional eccentric braces are the same,they are just provide lateral stiffness for structures;In elastic-plastic stage,the eccentric buckling restrained braces and he energy beam section produce plastic deformation,they dissipate seismic energy together to protect the main structure from destruction.Contrast the maximum axial force of each floor,the results of the analysis shows that the part of the brace was still in the stage of elasticity,if consider from the aspects of economy,we can reduce the amount of brace on the premise of meet the specification requirements and safety.