不考虑几何刚度的桁架结构非线性分析方法  

Nonlinear analysis method of truss structures with no consideration of geometric stiffness

作　　者：范秀娟 陈安全 张颖 杨耀 Fan Xiujuan;Chen Anquan;Zhang Ying;Yang Yao(School of Architecture and Engineering,Neijiang Normal University,Neijiang Sichuan 641100,China)

机构地区：[1]内江师范学院建筑工程学院,四川内江641100

出　　处：《山西建筑》2025年第3期50-56,共7页Shanxi Architecture

基　　金：内江市基础研究与应用基础研究项目(项目编号:NJJH202316);内江师范学院科研资助项目(项目编号:2023ZD03);内江师范学院大学生创新创业训练计划资助项目(项目编号:X2024077)。

摘　　要：一般进行结构非线性分析时,需特别考虑在大变形情况下结构刚度的变化,但切线刚度或几何刚度的推导过程较为复杂,众多研究关注于结构单元刚度矩阵的推导而忽略了非线性分析的整体过程。基于增量迭代非线性分析的力学机制,在保证桁架单元节点恢复力求解精度的情况下,仅考虑弹性或弹塑性刚度而不考虑桁架结构的几何刚度也可以分析桁架结构的非线性行为。通过与常规考虑几何刚度的情况进行对比分析,计算结果十分吻合,只是增加了少量的计算时间与迭代次数。此不考虑几何刚度的桁架结构非线性计算过程物理意义清晰,可推广至其他类型的结构。The change of structural stiffness in the case of large deformation should be specially considered in the nonlin-ear analysis of structures,However,the derivation process of tangential stiffness or geometric stiffness is complicated,so many researches focus on the derivation of structural element stiffness matrix and ignore the whole process of nonlinear a-nalysis.Based on the mechanical mechanism of incremental iterative nonlinear analysis,the nonlinear behavior of the truss structure can be analyzed by using only elastic or elastic-plastic stiffness without considering the geometric stiffness of the truss structure while ensuring the solution accuracy of the element node recovery force.By comparison and analysis with the conventional geometrical stiffness,the calculated results are in agreement,but the calculation time and iteration times are increased slightly.The nonlinear calculation process of truss structure without considering geometrical stiffness has clear physical meaning and can be extended to other types of structures.

关 键 词：桁架结构 几何非线性 材料非线性 增量迭代法 几何刚度 

分 类 号：TU311[建筑科学—结构工程]