Determination of mechanical response of non-linear viscoelastic solids based on frechet expansion

This paper deals with the determination of mechanical response of a non-linear viscoelastic solid based on a Fréchet expansion. In the first portion, a modified superposition principle, suggested earlier by various authors, is arrived at from a slightly different point of view. The effect of such a principle on the kernel functions and a geometric interpretation are discussed. In the later portion, the tests required for the experimental determination of the kernel functions are discussed. It is seen that besides the tests suggested by Onaran and Findley for the two-dimensional case, three additional tests are needed for the three-dimensional case to compute the response under constant combined stress.