3种材料模型在钢管混凝土有限元中的比较

Comparison among three material models in FEA of CFT

文章采用Von Mises、Mohr Coulomb和Drucker Prager 3种通用模型分别对带约束拉杆和无约束拉杆的方形、矩形钢管混凝土短柱轴压承载力进行有限元分析,探讨每种混凝土模型的特点以及在钢管混凝土有限元分析中的优缺点,并与已有的34个钢管混凝土短柱轴压试验结果对比,得出与静水压力无关,且忽略混凝土塑性体积膨胀的Von Mises模型无法考虑钢管对核心混凝土的约束作用以及约束拉杆的影响,而采用不相关流动法则的Mo-hr Coulomb和Drucker Prager模型,由于考虑静水压力和塑性体积膨胀,分析钢管混凝土短柱轴压承载力比VonMises模型更符合试验结果,而且两者计算结果很接近。

This paper performed finite element analyses（FEA） of the axial strengths of square and rectangular concrete filled steel tubular（CFT） stub columns with and with no binding bars by adopting three general models respectively—Von Mises,Mohr Coulomb and Drucker Prager,discussed the features of each model and its superiority and limitation in FEA of CFT,and made comparison between the axial strengths from FEA and the existed experiments of 34 CFT stub columns.Comparison shows that Von Mises model regardless of hydrostatic stress and concrete plastic volume dilatancy can not consider the confinement of core concrete and the influence of binding bars.Mohr Coulomb and Drucker Prager models with non-associated flow taking hydrostatic stress and volume dilatancy into account agree better with the experimental results than Von Mises model in simulation of the axial strengths of CFT,and there is little difference between them.