Direct calculation of buckling strength of imperfect structures

This paper is concerned with the direct calculation of buckling strength of an imperfect structure. The main assumptions are that, for the perfect structure, there is a symmetric or a linear fundamental path and the corresponding ®rst critical point is a simple symmetry-breaking or a simple bifurcation point. An extended system of limit points is proposed for which the newly introduced scaling parameters are regular solution and thus standard methods can be used to compute them. Using the extended system, one can directly obtain the exact buckling loads without tracing the postbuckling paths. An ecient implementation of Newtonʹs method solving the extended system is presented and numerical examples are giv