Deformation and fracture in one-dimensional creep problems

It is assumed that irreversible deformation is a result of shearing in certain planes. In perpendicular directions to these planes, normal strain undergoes change that is proportional to the associated shear. This approach allows accounting for growth of fractures and pores in the background of increasing creep strains without using Kachanov-Rabotnov's kinetic equation for development of damage. Material begins failing when maximum shear creep strain reaches critical value, which initiates drop in shear strength. Using the model based on the maximum shear stress and the exponential law, the authors solve problems on deformation and failure of an elastic-creeping body at the stages of unstable and stable creep.