Post-buckling analysis of planar elastica using a hybrid numerical strategy

Many structural mechanics problems, such as post-buckling of elastica, involve determining multi-equilibrium states of a nonlinear system. Typically, the stable equilibrium states are found by searching for minima of the potential energy function subjected to some constraints. In this paper, the method of genetic algorithm combined with the quasi-Newton method is applied to search for the multiple minima of the strain energy of various elastica problems. The proposed hybrid methodology is relatively straightforward to implement and is adopted to study post-buckling behaviour of planar elastica modelled as multi-link systems for various boundary conditions and sidewall constraints.