冲击荷载下矩形钢管混凝土柱-钢梁节点受力性能数值模拟

Numerical simulation of concrete-filled steel rectangular tubular column and steel beam joint under impact load

为研究矩形钢管混凝土柱-钢梁节点在冲击荷载下的力学性能,在总结归纳相关文献的基础上,选取合理的模型尺寸和本构关系,利用有限元软件ABAQUS对落锤冲击荷载下的钢管混凝土柱-钢梁节点受力性能进行数值模拟。通过设置接触对用来考虑钢管壁与混凝土间的粘结滑移效应,采用面面接触方式模拟冲击体与构件之间的接触作用,利用接触应力法对试件的动力响应进行分析,最终获得试件冲击力时程曲线和核心混凝土的应力云图;同时,考虑混凝土损伤塑性对节点核心区应力变化的影响。研究表明:冲击力峰值的计算值与理论值吻合较好,考虑混凝土损伤塑性可以提高数值模拟精度。

Based on the relevant literature on the selection model of reasonable size and constitutive relation,numerical simulation of CFST column and steel beam joint under impact load test is completed by finite element software ABAQUS in order to study the mechanical properties of concrete-filled steel rectangular tubular column and steel beam joint under impact load. By the method of establishing the contact pair between the core concrete and the steel tube,the bond-slip effect is considered. In addition,the contact action is simulated between the impact body and the component via surface-contact method. The dynamic response of the test component under different conditions is discussed by means of contact stress. Accordingly,the time-history curve of impact load and the stress nephogram of core concrete are protracted and the stress changes are compared and analyzed in the joint core area with and without damaged-plasticity. It proves that the numerical simulation of impact force peak agrees well with theoretical calculation and the accuracy of numerical simulation in CFST structure can be improved with concrete damaged-plasticity.