Tensorial Generalization of Uniaxial Creep Laws to Multiaxial States of Stress

Abstract

In this chapter a method is developed in order to find tensorial constitutive and evolutional equations based upon empirical uniaxial constitutive laws found in experimental investigations. For engineering applications it is very important to generalize uniaxial relations to multiaxial states of stress. This can be achieved by applying interpolation methods for tensor functions,as pointed out in detail in this chapter. It is illustrated that the scalar coefficients in tensorial constitutive equations can be expressed as functions of the irreducible invariants of the argument tensors and of the empirical constitutive laws found in uniaxial tests.