Numerical treatment of complete load-deflection curves

作     者：Magnusson, A Svensson, I 

作者机构：Univ Lund Dept Solid Mech S-22100 Lund Sweden 

出 版 物：《INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING》 (国际工程数值法杂志)

年 卷 期：1998年第41卷第5期

页      面：955-971页

核心收录：

学科分类：08[工学] 0701[理学-数学] 

主　　题：numerical algorithms path following technique singular points deflation technique branch switching 

摘      要：A method for direct computation of complete load-deflection curves, including both primary and secondary branches, as well as exact calculation of singular points is presented. The method used for path following is the cylindrical arc-length method in accordance with Crisfield.(1) To calculate singular points, an extended system, as proposed by Keener and Keller,(2) has been adopted. The numerical problems arising from ill-conditioned stiffness matrices near the singular points, are circumvented using a deflation technique. By a modification of the constraint equation used in the arc-length method, a reliable method for branch switching has been obtained. This leads to a unified approach to complete path following of structures with limit and bifurcation points. The use of this approach is demonstrated both on a simple two-bar truss as well as on a star-shaped shallow truss dome which exhibits complex stability characteristics. Comparisons are made with calculations found in the literature. (C) 1998 John Wiley & Sons, Ltd.