E. A. Storozhuk

Physically and Geometrically Nonlinear Static Problems for Thin-Walled Multiply Connected Shells

Physically and geometrically nonlinear two-dimensional problems are formulated for multiply connected thin shells (weakened by several curvilinear holes). A technique and algorithm are proposed for their solution with allowance for elastoplastic strains and finite deflections of shells under static loading. Numerical results for a shell with two circular holes are presented and the stress concentration is analyzed

Elastoplastic state of flexible cylindrical shells with a circular hole under axial tension

The elastoplastic state of cylindrical shells with a circular hole is studied considering finite deflections. The material of the shells is isotropic and homogeneous; the load is axial tension. The distribution of stresses, strains, and displacements along the hole boundary and in the zone of their concentration is studied by solving a doubly nonlinear problem. The data obtained are compared with the solutions of the physically and geometrically nonlinear problems and a numerical solution of the linear elastic problem

On the stress distribution near a stiffened elliptical opening in a cylindrical shell beyond the elastic limit

The basic nonlinear relations describing the stress-strain state of flexible thin-walled elements (rods, rings) that stiffen the contour of curvilinear openings in shells with allowance for the plastic deformation of their materials are presented. The Lagrange variation equation is used to obtain sets of nonlinear resolving equations for a shell with a stiffened elliptical opening. Successive-approximation and finite-element methods are used to solve the nonlinear problems. Numerical results are given for an elastoplastic cylindrical shell loaded by an internal pressure of given intensity. The distribution of maximum stresses in the area of an elliptical opening with and without a stiffening ring is analyzed. The data obtained in elastoplastic and linearly elastic formulations of the problem are compared.