无约束段对工字形内芯防屈曲支撑滞回耗能性能的影响

摘要

设计了12个无约束段的防屈曲支撑构件,利用ABAQUS软件对其进行有限元分析,研究无约束段长度、是否利用槽钢加强无约束段及加强槽钢的长度和厚度对构件滞回耗能性能及承载力的影响.结果表明:无约束段长度对防屈曲支撑构件滞回耗能性能及承载力影响显著,当无约束段长度与构件在轴力作用下产生的最大位移近似相等时,构件耗能效果更明显;经槽钢加强的构件具有良好的滞回耗能性能及承载力;无约束段加强槽钢的长度对构件滞回耗能性能与承载力影响显著,加强槽钢的长度为无约束段长度的2倍时,构件具有更好的滞回耗能性能与承载力;加强槽钢的厚度对构件的滞回耗能性能与承栽力影响不大,设计构件时可适当减小槽钢的厚度以提高材料的利用率.%12 different buckling-restrained braces with unconstrained segments were designed,and finite element analysis was carried by ABAQUS software to study the influences of unconstrained length,whether the channel strengthened unconstrained segment or not,and the channel with different lengths and thicknesses on the hysteretic energy dissipation and bearing capacity of components.The results show that the length of the unconstrained segment has a significant influence on the hysteretic energy dissipation performance and bearing capacity.The influence of energy dissipation is more obvious when the length of unconstrained segment is equal to the maximum displacement of component under axial force.The components strengthened by channels have good hysteretic performance and bearing capacity.The length of unconstrained segment strengthened by the channel has obvious influence on the hysteretic energy dissipation performance and bearing capacity.When the channel length is 2 times than unconstrained segment length,the components have better energy dissipation and bearing capacity.Strengthening channel thickness has little effect on the hysteretic behavior and bearing capacity of components,so the thickness of the channel can be reduced in design to improve the utilization rate of materials.