Design And Application Of Buckling Restrained Brace With Double Yield Point

As a new type of yielding energy dissipation member,buckling restrained braces can fully yield under tension and compression,and have stable hysteretic behavior and good energy dissipation capacity.However,most of the buckling restrained braces are designed to dissipate energy by yielding under rare earthquakes and remain elastic under small displacements,which makes the form of energy dissipation more single and less economical.In order to achieve the multi-stage energy consumption of energy dissipation members,a double-stage yield buckling restrained support is proposed,which is composed of metal damper and Q355 steel core plate buckling restraint support.This paper mainly does the following work:(1)The formulas for calculating the bearing capacity and stiffness of the metal energy dissipation plate are derived by theoretical method,and the formulas for ensuring the stability of each part of the buckling restrained brace and the relevant parameter limits are analyzed.(2)Three groups of Q355 were designed The results show that when the core plate is in the elastic state,the shear damper in the shear plate buckling restrained brace composite seismic member will yield first and dissipate energy,and the shear plate will fracture before the core plate enters the plastic state,and the first and second-order debonding will occur the results show that the performance of the second-order buckling restrained brace is not affected by the first-order shear damper;after the core plate enters the plastic state,the energy dissipation performance of each stage is good,and the shear steel plate buckling restrained brace composite seismic members can better achieve the purpose of two-stage energy dissipation,which provides a reference for the subsequent study of similar energy dissipation components.(3)The key geometric parameters affecting the performance of Q355 steel core plate buckling restrained braces are numerically analyzed.Through SAP2000 numerical analysis,the results show that the three types of dampers have better damping effect,and the shear plate buckling restrained braces composite damping member has the best damping effect.