考虑多种非线性变形的RC框架单元模型

A RC Frame Model with Consideration for Various Nonlinear Deformation Component

提出一种钢筋混凝土框架结构弹塑性地震反应分析的杆件单元模型 ,着重介绍节点滑移子单元和剪切子单元的柔度矩阵的建立过程 .该单元模型把框架结构构件 ,由分布弹塑性梁子单元、节点滑移子单元和剪切子单元等 3个在节点上串联的子单元组成 .这两个子单元模型能够分别考虑纵向钢筋在节点内的粘结滑移 ,构件关键受力区域的剪切变形随复杂加载历史的变化过程 .该法从子单元柔度矩阵的计算到单元刚度矩阵的建立过程 ,力学概念明确 ,大大简化多种变形成分和复杂加载历史下 ,构件单元刚度矩阵的建立过程 。

A member element model is presented for analysing elasto plastic seismic response of a RC frame structure, with emphasis on the process of forming flexibility matrix of joint slip subelement and shear subelement. This element model looks upon frame structure as connection spread elastoplastic beam subelement and joint slip subelement and shear subelement in series on the joint. The latter two subelement models consider respectively the anchorage slip of longitudiral reinforcing steel in the joint and the change of shear deformation of member in critical force zone with the history of complex loading. The method presented here is clear and definite in mechanical concept, from flexibility matrix calculation of subelement to the process of forming stiffness matrix of element. It greatly simplifies the process of forming stiffness matrix of member element under various deformation component and complex loading history. It can be applied to the analysis of nonlinear seismic response of RC frame structures.