基于纤维模型的外粘型钢加固混凝土柱静力弹塑性分析

Nonlinear static analysis on RC column strengthened with externally bonded steel frame based on fiber model

基于纤维模型,引入约束混凝土本构关系,提出了对外粘型钢加固混凝土柱进行静力弹塑性分析的方法,并在OpenSees平台上编程实现.在此基础上,对约束混凝土本构参数进行了敏感性研究,探讨了混凝土材料本构模型对截面层次的弯矩曲率关系和构件层次的荷载位移关系的影响.经与2次不同的试验结果比较,计算的荷载位移曲线与试验结果符合良好,表明在外包钢加固柱进行弹塑性分析时,对约束混凝土采用Kent-Scott-Park本构模型可以获得良好的分析结果.本构模型中约束增强系数和应变参数对于分析结果,特别是弹塑性阶段结果的准确性起到非常重要的作用.

Based on a fiber model, the approach for nonlinear static analysis on strengthened column is proposed, and the procedure on an OpenSees platform is programmed by introducing the constitutive relation of confined concrete. After this, a parametric sensitivity study is performed for a confined concrete constitutive model. The effects of the constitutive model of confined concrete on the section level of moment curvature relation, and on the component level of load displacement relations is discussed. The load-displacement curves from simulation are in good agreement with two different experimental results. It is shown that better results from a numerical simulation of inelastic analysis of the strengthened column can be obtained with a Kent-Scott-Park constitutive model of confined concrete. The parameters of confined action coefficient and strain play very important roles in the accuracy of simulation especially in the inelastic stage.