Abstract

Shells are structures occurring in many applications in nature and technology. Due to their inherent high ratio of stiffness over weight they can exhibit extraordinary structural behaviour. On the other hand they can be quite sensitive with respect to imperfections in geometry or inappropriate loadings. The computation of shell structures is therefore interested in finding suitable shell models and discretisation methods to describe accurately the interplay of geometry, kinematics and mechanics of shells. In the talk, a geometrically non-linear shear-flexible shell formulation is presented which can be used for thin and thick shells. The deformed configuration of a shell is parameterised using the mid-surface position vector and an additional shear vector for describing the out- of-plane shear deformations. The mid-surface has to be interpolated with C1-continuous shape functions for which smooth subdivision shape functions are applied. Subdivision shape functions allow also to relax continuity to enable non-manifold geometries which arise in many engineering applications. The subdivision shell formulation is used for optimising a plate with stiffeners.