Creep analysis of a thin tube and continuum damage mechanics application

In this paper, the behavior of a thin walled tube, which is widely used in many industries, under a constant internal pressure and a cyclic temperature gradient across its wall thickness was studied. In order to study the stress–strain variation across the thin walled tube during the cyclic loading, a coupled elastoplastic and creep continuum damage law was used and the necessary stress–strain relations were developed. The creep strain rate was obtained for different combinations of constant mechanical and cyclic thermal loadings by using an incremental numerical procedure. The results were shown in the Bree's diagram. Four different regions were obtained on the Bree's diagram for different normalized total equivalent strain rate order which varied from less than 0.001 to more than 0.1.