Changes in Residual Stresses in the Vicinity of a Continuity Defect in an Elastoviscoplastic Material under Repeated Loading

Abstract

The results of calculations of the stress-strain states of an elastoplastic material containing a single cylindrical continuity defect and loaded with external pressure are presented. The hydrostatic pressure on the surface distant from the defect initially increases, remains constant for some time and then gradually decreases to zero. The process of comprehensive compression leaves, after unloading, a formed level and distribution of residual stresses in the vicinity of the continuity defect. The change in such stresses is calculated upon repeated loading and unloading. Intensity and nature of repeated loads are considered identical to the original ones. Calculations are carried out within the framework of the stated one-dimensional problem of the theory of large deformations. The material is assumed to be incompressible. The development of areas of viscoplastic flow in the active part of the process and their attenuation during unloading are taken into account. Changes in the geometric dimensions of the evolving defect are assessed.