Dynamic shear tests for the evaluation of the effect of the normal load on the interface fatigue resistance

This paper focuses on investigating the fatigue performance of the interface between asphalt layers. The aim is to highlight the relationship between the state of stress and the interface fatigue failure. Several combinations of normal pressure and shear load amplitude have been tested to derive a comprehensive law. A new model is proposed to join the contributions of normal stress and shear stress to the interface fatigue behavior. The model is a regression surface in a 3D space where the stresses are the independent variables while the dependent one is the number of repetitions corresponding to characteristic moments of the test.