基于纤维模型的CFT框架柱滞回性能模拟及模型灵敏度分析

Hysteretic behavior simulation and sensitivity analysis of CFT structural column based on a fiber model

研究了基于纤维模型的CFT框架柱滞回性能模拟的建模方法,建立了基于不同材料本构模型的CFT框架柱数值模型,并探讨了材料本构关系、纤维截面网格划分、积分点数量等因素对模拟精度的影响。以试验为依据,运用Opensees软件,通过计算结果与试验结果的对比,分析了影响滞回模型计算精度的主要因素。结果表明,受约束混凝土本构关系的下降段,钢材本构关系的强化段,是影响滞回模型准确性的主要因素,而网格划分和积分点数量的影响则主要体现在程序运行速率方面。研究将为基于纤维模型法的CFT框架柱滞回性能模拟分析提供理论依据。

Based on a fiber model,the simulating method of the hysteretic behavior of concrete-filled steel tube（CFT） frame columns is studied.The numerical model of CFT frame columns is established by different material constitutive laws.Then the effect of the constitutive relation of material,the mesh division of fiber cross-section and the number of integration points on the simulation precision is discussed.The main effect factors for the hysteretic model is analyzed through the comparison between test results and calculated results supplied by Opensees software.The results show that the descending segment of confined concrete constitutive relation and the hardening segment of steel constitutive relation are the main factors,which affect the accuracy of the hysteretic model.On the other hand,both the mesh division of the fiber cross-section and the number of integration points affect the calculation efficient.The research can provide for theory basis for the simulation analysis of hysteretic behavior of CFT frame columns.