Experimental investigation on asphalt strength loaded along three mutual orthogonal directions at different temperatures

The study of the mechanical characteristics of asphalt, assumes more and more importance in the road pavement field, in order to estimate the response of the material, loaded by the road traffic. In this view, the Authors have developed a new apparatus for Triaxial Tests, herein called M.P.T., for testing asphalt cubical specimens, that is able to simulate in laboratory the real loading conditions of the material, that is put through strain stresses. The paper aim is to provide a contribution to the study of the response of the wearing course asphalt, in terms of stresses and strains under triaxial compression load, that induces the reaching of yielding in the material at different temperatures. The experimental investigation, that has been made by changing appropriately the values of the three main parameters (I1, J2, m) of the Theory of Continuum Mechanics, has allowed the determination of the yielding function of asphalt in the compression domain of the principal stress space at different temperatures.