Study On Numerical Simulation Of Seismic Performance Of New Type Of All-steel Buckling-restrained Brace

The traditional all-steel buckling-restrained braces with single plate is widely used in the seismic design of various buildings due to its light weight,convenient design and manufacturing,and good hysteretic performance.In order to improve the flexural rigidity of constraint components,reduce the dead weight of the buckling-restrained braces and improve the usage rate of the steels,this paper proposes a new type of all-steel bucklingrestrained braces,and the peripheral constraint components adopts the "plate-wave plate-plate" along the thickness direction of inner cores.The seismic performance of new buckling-restrained braces is studied by theoretical analysis and numerical simulation.This article mainly studies the following aspects:(1)According to the experimental design parameters,the finite element model of traditional all-steel buckling-restrained braces with single plate is established.The hybrid nonlinear hardening model is selected as the constitutive model of the material for finite element analysis,and the analysis results are compared with the experimental data to verify the accuracy of the constitutive model and modeling process.Furthermore,the influence of width-to-thickness ratio of the inner core,the ratio of gap and the inner core thickness on the ultimate bearing capacity of the traditional buckling-restrained braces is studied.(2)The force mechanism of the new type of all-steel buckling-restrained brace is analyzed.Based on this,the global stability of the new buckling-restrained brace is analyzed,and the calculation formula of the critical buckling load is obtained.The constraint components were subjected to force analysis,and the calculation formula of t he local buckling load of the inner plate,wave plate,external plate and cover plate in the constraint component was obtained.The local stability of the inner core was analyzed by the buckling theory of the plate,and the reasonable value range of the inner core width to thickness ratio was obtained.(3)Establish a finite element model of all-steel buckling-restrained brace with single plate,study its ultimate bearing capacity and hysteretic energy dissipation under axial compressive and cyclic loads,and compare it with traditional buckling-restrained brace.The advantages and disadvantages of the new buckling-restrained brace.Furthermore,the influence of the thickness of the inner plate,the thickness of the wave plate,the thickness of the external plate,the thickness of the cover plate and the wave number of the wave plate on the ultimate bearing capacity of the new buckling-restrained brace is studied.