| Under the strong earthquake,the axial bearing capacity,deformation and energy dissipation capacity of the ordinary steel brace often decrease sharply due to the compression buckling,resulting in the structural damage.At present,buckling braces are usually used in engineering to improve the deformation and ductility.The buckling resistant steel support is composed of core unit and peripheral restraint unit,the core element bears axial tension and pressure,and the peripheral restraint element can restrain the buckling of the core element to ensure that it only yields under the axial force.The existing research mainly focuses on the overall stability and hysteretic performance of BRB support.In terms of its failure mode,its plastic region is generally concentrated in a centralized position of the core unit,resulting in low deformation capacity.Based on this,a kind of ductile assembled buckling resistant brace with step-by-step yield is proposed in this paper,DA-BRB is composed of two hollow rectangular steel pipes,wedge-shaped core plate,gasket,unbonded material and highstrength bolt.It is divided into several sections by setting limit baffle on the core plate.The limit baffle can effectively control the core plate section to yield step by step and improve the axial deformation capacity of da-brb support.In this paper,the hysteretic behavior of DA-BRB is studied experimentally and simulated by finite element method,the research contents are as follows:(1)Twelve DA-BRB specimens were designed and manufactured,the mechanical mechanism and failure mode under the action of low cycle reciprocating horizontal load are clarified,The effects of different core material,core size and core form on the mechanical properties of the new da-brb support were investigated;(2)The general finite element software ABAQUS is used to analyze the DA-BRB specimens,the hysteretic curve,skeleton curve,axial stiffness and hysteretic energy consumption of the specimen are mainly investigated,further verify the accuracy and rationality of finite element simulation.(3)Five series of 10 new DA-BRB support specimens were analyzed by using the general finite element numerical simulation software ABAQUS,the effects of design parameters,such as core plate type,core plate wedge ratio,core plate section number,core plate width thickness ratio and core plate material,on the seismic performance of the specimens,such as hysteretic curve,skeleton curve,axial stiffness and hysteretic energy consumption,are mainly investigated. |
