On modelling and non‐linear elasto‐plastic analysis of thin shells with deformable junctions

The undeformed base surface of the irregular thin shell is modelled by the union of a finite number of regular smooth surface elements joined together along spatial curvilinear surface edges. The equilibrium conditions are formulated by postulating an appropriate form of the principle of virtual work, where also deformability of shell junctions is taken into account. The PVW is then discretised by C1 finite elements and the incremental‐iterative procedure is applied to solve the highly non‐linear BVP. As an example, the axisymmetric deformation state is calculated in the casing of devise measuring the external pressure and having two pairs of circular welded junctions. The problem is solved within the elasto‐plastic range of material behaviour with linear combination of isotropic and kinematic hardening, and deformability of the junctions is taken into account.