基于有限单元柔度法和刚度法的几何非线性空间梁柱单元比较研究.PDF

第22 卷第3 期 工 程 力 学 Vol.22 No.3 2005 年 6 月 ENGINEERING MECHANICS June 2005 文章编号：1000-4750(2005)03-0031-08 基于有限单元柔度法和刚度法的 几何非线性空间梁柱单元比较研究 *陈 滔，黄宗明 (重庆大学土木工程学院，重庆 400045) 摘 要：分别基于有限单元柔度法和有限单元刚度法二阶分析理论，采用纤维模型梁柱单元编制了钢筋混凝土杆系结 构二阶非线性分析程序；分别采用这两种方法对几个典型试验实例进行了计算机模拟分析，通过模拟分析结果的对比， 对有限单元柔度法与有限单元刚度法处理几何非线性问题的效果与效率进行了比较研究。结果表明：对于几何非线性 问题，尤其是对于处理下降段(非稳定阶段) 问题，基于柔度法的梁柱单元无论从计算效率还是计算效果上都明显优于基 于刚度法的梁柱单元，有限单元柔度法是目前处理杆系结构材料与几何双重非线性问题最为有效的分析方法。 关键词：结构工程；非线性有限单元法；有限单元柔度法；梁柱单元；几何非线性；二阶效应 中图分类号：TU375 文献标识码：A COMPARISON BETWEEN FLEXIBILITY-BASED AND STIFFNESS-BASED GEOMETRICALLY NONLINEAR BEAM-COLUMN ELEMENTS * CHEN Tao , HUANG Zong-ming (College of Civil Engineering, Chongqing University, Chongqing 400045, China) Abstract: Flexibility-based and stiffness-based fiber model beam-column elements for the second order analysis are investigated in this paper. Several typical examples with experimental data are selected for computational effectiveness comparison between the two methods. The validity of flexibility-based beam-column elements is also examined for the second order analysis of space member structures. The results show that flexibility-based beam-column elements are apparently superior to stiffness-based beam-column elements in dealing with instability problems of structures and the flexibility-based beam-column element is presently one of the most practical and efficient element models handling material and geometrically nonlinear problems of framed structures. Key words: structural engineering; nonlinear finite element m