This paper analyses two types of test, used in Canada, France and United States, allowing laboratory characterization of the fatigue performance of bituminous mixes. The Extension-Contraction (EC) test, realized on a cylindrical sample, and the Four-Point Bending (4PB) test, realized on a rectangular beam, are analysed. The tested material is a High Modulus Asphalt Concrete (HMAC). Fatigue tests will be carried out in displacement control under cyclic sinusoidal at 10°C and 10 Hz. Our results show that the standard analysis criterion, noted N_(f50%), associated with a 50 percent drop in stiffness (or initial modulus, |E_0~*|) during fatigue test, appears to be limited. However, by adopting a failure criterion, noted N_(fE_ΦE), associated with the evolution of the stiffness (|E*|) and the phase shift angle (Φ_E) in the Black space, the results then show that the coefficients of the Wohler curve become more comparable between for the two types tests. The new approach, based on N_(fE_ΦE) , appears to be a good option for overcoming the limitations and weaknesses of the classical approach, based on N_(f50%). However, the determination of the phase shift angle (Φ_E) between the displacement and the force must be defined rigorously during the test to clearly determined the fatigue life established by N_(fE_ΦE) .
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