Deformation and Long-Term Strength of a Thick-Walled Tube of a Physically Non-Linear Viscoelastic Material under Constant Pressure

An exact solution is constructed for the problem of creep and fracture of a hollow cylinder made of a physically nonlinear rheonomic isotropic incompressible material, which obeys Rabotnov’s constitutive viscoelasticity relation with two arbitrary material functions, under the action of internal and external pressures. Сlosed form equations for long-term strength curves are derived using three versions of a deformation fracture criterion, and the strain intensity, the maximum shear strain, or the maximum tensile strain is chosen as the measure of damage. Their properties are analytically investigated for arbitrary material functions of the constitutive relation.