Viscoelastic constants of a soda-lime-silica glass

A complete development of the viscoelastic constants is given in the framework of the viscoelastic theory using the definition of Tschoegl and the notion of moment introduced by Gy et al. for the linear viscoelasticity. Viscoelastic constants were considered as 'constants' because these dimensionless parameters do not change with loading level for a linear viscoelastic material. In addition, for a thermorheologically simple viscoelastic material, some of them are temperature-independent, whereas others follow the temperature-dependence of the Poisson ratio. Since some of them have a simple physical meaning, all models have to take them into account for simulating mechanical behavior of viscoelastic materials. Experimental measurements for some of viscoelastic constants under shear and uniaxial loadings allow determination of bulk equilibrium elastic modulus and other viscoelastic constants, used for describing hydrostatic pressure and biaxial behavior.