摘要
为准确描述钢筋混凝土结构局部的受力情况,通常需要采用微观模型来进行非线性有限元分析.将梁柱单元建立在弹塑性纤维模型的基础上,直接从材料本构关系出发,对平面钢筋混凝土框架结构进行了全过程非线性静力分析.在框架结构与梁柱单元之间用刚度法,组装杆件刚度得到结构刚度;杆件与杆件内部积分点处的横截面之间采用柔度法,基于杆端力和截面力的平衡获得杆件刚度;每个横截面通过平截面假定协调纤维变形,同时考虑了几何非线性,由纤维的刚度得到截面刚度.为追踪非线性反应的软化段,求解时选取柱面弧长法.同时选取实例分别进行单向推覆和低周反复加载试验的程序模拟,得到了较好的效果,并提出进一步优化改进的建议.
For the exact description of local forces in RC structure, usually micro-models should be used for the nonlinear analysis. In this paper the beam-column element based on elasto-plasticity fiber model is established. According to the constitutive models of the materials, the whole process static nonlinear analysis of the RC frame is conducted. Stiffness based method is used between poles and frame, and frame stiffness can be worked out by assembling the pole stiffness. Flexibility-based method is adopted between the pole and sections, and based on the equilibrium between the sections and pole the stiffness of poles can be obtained. Plane-assumption is used to harmonize the strain of fibers with the displacement of the section, and section stiffness can be figured out from fiber stiffness, in which the geometrical nonlinearity is considered. Cylinder arc-length method is used in the increment iterative process and some instances with the fiber model are verified by the push-over and cyclic load reversals experiments. Suggestions are given for the improvement and ootimization of the fiber model.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2005年第A01期129-132,共4页
Journal of Southeast University：Natural Science Edition
关键词
纤维模型
非线性分析
柔度法
弧长法
fiber model
nonlinear analysis
flexibility method
arc-length method
