Continuum damage mechanics (CDM) is considered as a general method to treat the progressive deterioration of materials and structures in the framework of continuum mechanics. The damage-coupled creep mechanics based on CDM is discussed in the paper first, including the description of effective stress concept and the expression of all field equations in creep. The general formulation of a constitutive relation is presented after simplifying treatment for the sake of the modeling of creep damage problem in computational mechanics. The parametric variational principle (PVP) developed from the idea of optimal theory is introduced to establish the numerical principle of structural analysis for damage-coupled creep mechanics, including both the associated potential variational principle and the corresponding FEM formulations. The possibility of applying the principle presented by this paper to the life and damage prediction of structural components is finally illustrated by some examples on creep experiments for three kinds of materials.

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