Direct evaluation of the local stability of structures using nonlinear FE solutions

In this paper, we propose three practical methods for directly evaluating stability in a local structural part of a large structure (local structure). The local stability is assessed by investigating global external load, local internal force, local strain energy, and local displacement, all calculated through nonlinear finite element (FE) analysis. A great advantage of the proposed methods is that they do not require local finite element analysis of the target local part and are applicable to arbitrarily-shaped local parts of a global structure. In addition, unlike previously developed methods, the proposed methods fully consider complicated interactions between local and global structures. The three evaluation methodologies are presented, and their practical effectiveness is demonstrated through several numerical examples.