柱脚耗能的连柱钢支撑结构抗震性能分析

SEISMIC BEHAVIOR ANALYSIS OF LINKED COLUMN STEEL BRACED FRAME WITH ENERGY DISSIPATION COLUMN BASE

为了提高连柱钢支撑结构耗能能力,增加耗能连梁进入塑性的程度,提出在柱脚处设置耗能连梁,形成柱脚可耗能的连柱钢支撑结构形式。设计了柱脚耗能的连柱钢支撑结构试件,采用ABAQUS有限元分析软件,对试件进行低周往复加载,分析耗能连梁长度和支撑跨跨度等设计参数对结构滞回性能的影响。分析结构的滞回曲线、骨架曲线、刚度退化曲线以及耗能能力等方面的特征,结果表明:柱脚可耗能的连柱钢支撑结构滞回曲线比较饱满,耗能能力较强,破坏模式是较为理想的。随着耗能连梁长度增加,结构的承载力和刚度下降,结构的耗能能力呈现先增加后降低的趋势,建议耗能连梁长度取值范围(1. 0～1. 51) Mp/Vp,其中,Mp为耗能连梁的塑性抗弯承载力,Vp为耗能连梁的抗剪承载力。随着支撑跨跨度的增加,结构的承载力和刚度以及耗能能力方面都有所增加。

In order to improve the energy dissipation capacity of linked column steel braced structure systems and increase the degree of plasticity of the link beam, it was proposed to install the link beam at the column base to form a type of linked column steel braced frame with energy dissipation column base. The specimens of linked column steel braced frame with energy dissipation column base were designed. Finite element analysis software ABAQUS was used to conduct a quasi static loading on these specimens, the influences of design parameters such as link beam lengths and brace spans on the hysteretic behavior of the structure were analyzed. The characteristics of the hysteretic curve, skeleton curve, stiffness degradation curve and energy dissipation capacity of the structure were compared. The analysis results showed that linked column steel braced frame with energy dissipation column base had full hysteretic curve, better energy dissipation capacity and reasonable failure mode. As the length of link beam increases, the bearing capacity and stiffness of the structure decreased, and the energy dissipation capacity increases and then decreased. The length of link beam showed be in the range of (1.0~1.51) M p/ V p, M p represents link‘s plastic flexural capacity and V \-p stands for link’s shear capacity. As the brace span increased, the bearing capacity and stiffness of the structure and the energy dissipation capacity were increasing.