Plastic Limit Analysis of Truss Structures Subjected to Progressive Collapse

Abstract

In this paper, a method to generate the required basic mechanisms in a plastic limit analysis of truss structures subjected to progressive collapse is presented. Rigid body motion of all members is introduced by constraint equations and at the same time releases are introduced. A set of basic mechanisms is obtained by solving the generated set of equations. Additional modification is necessary to put the mechanisms in the usual form of relative deformations for each member. The joint geometry of the structure and the member connectivity are the requirements of the proposed method. The method is thus applicable for programming and omits the hand generation process of the basic mechanisms in a limit analysis.