Limit analysis of orthotropic structures based on Hill's yield condition

The limit analysis problem, which permits the direct computation of the limit load of rigid-perfectly plastic solids and structures, is considered with reference to anisotrophic materials. As a starting step, attention is focused on Hill's orthotropic condition, for which an explicit expression of the dissipation power in terms of strain rates is established. On this basis, numerical procedures successfully employed in the isotropic (von Mises') case can be used in this context, as some examples illustrate.