Conventional FSM Model

A conventional FSM model (which is equivalent with a plate FEM model) considers both the Poisson effect and transverse plate flexure. If the analyzed plate elements are thin enough (which is always the case for cold-formed steel), and the applied finitization is sufficiently dense, both effects are considered in a correct way. Although these models still involve certain approximations (e. g. stresses/strains perpendicular to the plates are neglected), it is fair to say that FSM models calculate the elastic buckling of a thin-walled member with negligible error.