Convergent internal stresses and steady cyclic states of stress

It is proved that if two structures differing only in their initial internal stresses are subject to the same loading history, the distributions of internal stress will approach one another in regions of creep and plasticity as the loading proceeds. This theorem is used to prove the existence and uniqueness of steady cyclic states of stress. The application of the concept of a steady cyclic state to the analysis of structures under a repeated loading cycle is discussed.