Strength calculation algorithm for shell structures based on a four-node discretization element

The article describes a method for calculating shell structures taking into account transverse shear deformations during elastoplastic deformation. geometric relationships between the increments of in an arbitrary layer and components displacement vector, vector inclination angles normal are obtained on basis hypothesis S.P. Tymoshenko. slope increment performed from original position normal. physical stress tensor deformation at loading step were that they proportional, based theory plasticity. In finite element implementation developed algorithm, four-node fragment middle surface structure with nodes located vertices quadrangular was used. components, their first derivatives respect to curvilinear coordinates, as well rotation angle selected nodal variable parameters step. size stiffness matrix 44x44. algorithm tested test problems cylindrical using duralumin alloy diagram form two-link broken line material.