Elastoplastic Axisymmetric Stress–Strain State of Thin Shells Made of Materials with Different Compressive and Tensile Moduli

A technique of numerical analysis of the elastoplastic axisymmetric stress–strain state of thin isotropic shells with different tensile and compressive properties under mechanical loading is described. The technique is based on constitutive equations of plasticity that include either the third invariant or mixed invariants of the stress deviator. To specify the constitutive equations, experimental data known from the literature and obtained in testing tubular iron specimens in tension, compression, and torsion are used. Numerical results are analyzed.