柔度法考虑钢筋混凝土梁柱单元变形局部化的计算方法  

A METHOD CONSIDERING DEFORMATION LOCALIZATION OF RC BEAM-COLUMN ELEMENTS IN FLEXIBILITY METHOD

作　　者：谢凡[1] 沈蒲生[1] 王海波[2] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]中南大学土木建筑学院,湖南长沙410075

出　　处：《工程力学》2011年第10期118-123,共6页Engineering Mechanics

基　　金：国家自然科学基金项目(50908230)

摘　　要：基于性能的设计需要考虑结构及构件在地震荷载作用下的非线性反应,基于柔度法的分布塑性梁柱单元模型可以用较少的单元得到较为准确的结果,也可以很方便地处理因混凝土应变软化带来的变形局部化问题。但这种计算模型在处理局部变形时,若直接根据数值积分求解,计算结果与实际结果偏差较大,而且会出现随着积分点的增加,偏差越大的反常现象。该文分析了产生这一现象的数学力学原因,通过在单元的截面层次上将变形分离为弹性变形和塑性变形,对单元的塑性变形指定塑性区长度,得到了合理的解答。The nonlinear behavior of structures and members must be considered in performance-based seismic design of structures. Only a small number of elements are required to get accurate results if the force-based distributed plasticity model of beam-column elements is used. It is also convenient to deal with the localization of deformation induced by the concrete strain-softening with this model. But if the element is formulated directly by numerical quadrature when solving the localization, the results will deviate from the exact solutions with the number of quadrature points increasing. To solve this abnormal phenomenon, the deformation of section is divided into elastic type and plastic type, and the length of plastic zone in the element is specified, in such a way rational results are obtained.

关 键 词：梁柱单元非线性分析 柔度法 应变软化 变形局部化 高斯-洛巴托积分 塑性区长度 

分 类 号：TU375[建筑科学—结构工程] TU311.4