Snap‐Through and Bifurcation in a Simple Structure

Abstract

Basic characteristics associated with snap‐through, bifurcation and post‐buckling behavior of structures are illuminated and clarified. This is accomplished by presenting and examining in detail exact closed‐form global solutions for the load‐deflection response of a simple two‐bar planar truss. Three loading conditions are considered: vertical (symmetric), horizontal (anti‐symmetric) and combined vertical‐horizontal loadings. The symmetric loading case is well‐known and has been widely used as a bench mark problem for comparison of numerical solution algorithms. The two‐bar planar truss considered involves standard structural and material behavior models which are incorporated in many structural analysis codes, and it can be made to mimic a wide‐variety of types of behavior. Concrete examples of behavior which could cause computational difficulties in the numerical analysis of more complex structural models are valuable in the process of developing and improving solution algorithms for nonlinear structural analysis.