Viscoelastic Analysis of Diametral Compression of Asphalt Concrete

The diametral compression of short cylinders is generally accepted as the convenient and accurate test method for evaluating the mechanical properties of asphalt concrete mixtures. In particular, the test serves to determine the relation between the stresses and strains, with the assumption that it can be quantified by the elastic (resilient) modulus and Poisson's ratio. These parameters are used for both the asphalt concrete quality assessment and in elastic multilayer analytic or numerical predictions of pavement deflections. The elasticity-based test analysis used in practice accounts for viscous effects that asphalt concrete displays at moderate and elevated temperatures in a simplified fashion. The methodology presented in this paper incorporates the effect of viscosity in a rigorous manner, by deriving a linear viscoelasticity-based solution. The solution makes use of the elastic-viscoelastic correspondence principle and Laplace and Fourier transforms; it is valid for any load history. Specifically,...