Improved understanding of grouted mixture fatigue behavior under indirect tensile test configuration

This paper focuses on the long-term performance of a grouted mixture, a relatively new pavement material which consists of an open grade asphalt concrete whose voids are filled with cement mortar. Its peculiar characteristics, depending on mix design and level of filling, induce a variability of its mechanical behavior. The purpose of this paper is understanding how such variability affects the fatigue properties of the material, under indirect tensile test configuration. Experimental results have revealed a remarkable influence of stiffness properties on fatigue life. Following this observation, the fatigue behavior of grouted mixture is described through a new analytical model, which explicitly introduces the dependence of the fatigue life on the stiffness modulus. Comparative analysis demonstrates that the proposed analytical model significantly outperforms traditional fatigue modeling for the peculiar type of investigated composite pavement system.