矩形钢管混凝土柱初始缺陷随机有限元分析

Stochastic Finite Element Analysis of Initial Defects of Concrete-filled Rectangular Steel Tubular Columns

为研究矩形钢管混凝土柱核心区混凝土内部随机几何缺陷对构件承载力的影响,基于ABAQUS/Python二次开发,建立带有内部随机缺陷的钢管混凝土柱有限元模型。通过多次循环计算生成大量带有不同几何缺陷类型的模型,分析不同模型计算得到的承载力数值,总结缺陷分布位置和大小对结构承载力的影响规律。结果表明,缺陷的存在对结构轴向承载力影响较大,统计分析大量承载力数据可得其服从偏态分布;当缺陷率很小时,结构的承载力也能折减40%以上,且承载力降低很快,随着缺陷率的增大,结构承载力的折减速度有所减缓;位于结构两端靠近中间部位的缺陷对结构承载力的影响最小,位于结构中心部位的缺陷对结构承载力的影响最大。

In order to study the influence of internal random geometric defects of concrete in the core area of rectangular concrete-filled steel tubular column on the bearing capacity of members,a finite element model of concrete-filled steel tubular column with internal random defects is established based on the secondary development of ABAQUS/Python.A large number of models with different types of geometric defects are generated through multiple cycle calculations.By analyzing the bearing capacity values calculated by different models,the influence of the distribution position and size of defects on the structural bearing capacity is summarized.The final results show that the existence of defects has a great impact on the axial bearing capacity of the structure.Through the statistical analysis of a large number of bearing capacity data,it can be obtained that it obeys the skew distribution.When the defect rate is very small,the bearing capacity of the structure can also be reduced more than 40%,and the bearing capacity decreases rapidly.With the increase of the defect rate,the reduction speed of the bearing capacity of the structure slows down.The defects near the middle at both ends of the structure have the least impact on the structural bearing capacity,and the defects at the center of the structure have the greatest impact on the structural bearing capacity.