Performance testing of asphalt paving mixtures for hot condition using tension-compression test

In this paper, laboratory experiments were conducted on two different asphalt mixes, one using the Marshall mix design method (MMD) and the second using modified Marshall mix design (3M) method. The 3M method is based on the incorporation of two factors, the new asphalt binders (performance grade) and the Superpave gyratory compactor (SGC) as in Superpave mix design method, into the traditional MMD method. All specimens had the same mixtures of aggregate gradation incorporated with two different compaction methods and two asphalt grades using two different classification methods: asphalt cement binder (B60-70) based on the penetration test (Pen system) and PG 70-10 based on performance grade system (PG). However, there were some errors at low temperature (-25, -10 degrees C) and high temperature (54 degrees C), so these values may be discarded. The tension-compression complex modulus test vertical bar E*vertical bar is dependent on temperature and loading frequency. Thus, the results of this test will give a more accurate representation of the absolute value of the tension-compression complex modulus test vertical bar E*vertical bar that defines the elastic properties of a linear viscoelastic material subjected to a sinusoidal loading. In addition, 2-complex modulus (E*) and phase angles (Phi E*) in the test have been measured at temperatures of -25, -10, -5, 10, 25, 35 and 54 degrees C as well as frequencies of 25, 10, 5, 1, 0.5 and 0.1 Hz. The value of the dynamic modulus reflects the stiffness of the mixture and its resistance to deformation at a designated frequency and temperature. The results show an improvement in the vertical bar E*vertical bar in the modified 3M mix over the traditional MMD mix. The 3M method using asphalt binder PG 70-10 and gyratory compactor (SGC) as in Superpave mix design method, improves the vertical bar E*vertical bar of the asphalt mixture in HA climate. As well, intrinsic characteristics related to binder properties, aggregate gradation and compaction method in HA climate have the most significant effect on the predicted vertical bar E*vertical bar.