ON THE DESCRIPTION OF CYCLIC CREEP AND RATE DEPENDENT PLASTIC-DEFORMATION

A constitutive model is proposed to describe cyclic creep and other rate dependent plastic deformation. The model is general in concept and thus applicable to a wide variety of engineering materials such as metals, polymers, concrete, rocks and soils. Effect of temperature and deformation history is also included into the basic formulation. The main feature of the model is the concept of a family of nested hypersurfaces in a pseudo stress space. The pseudo stress space is defined by combining both stress and physical time. Thus the rate dependent plastic deformation may be treated as a pseudo rate independent process.