Evaluation of the effect of the loading frequency on Wohler's curve parameters of a high modulus asphalt concrete (HMAC)

The fatigue's behaviour of bituminous materials is affected by the loading frequency. For hot mix asphalt (HMA) with unmodified bitumen, previous research showed a decrease in fatigue life, under strain-control mode, by increasing loading frequency. However, the effect of loading frequency on polymer-modified HMA has not been investigated extensively and researchers have found opposite results using the same testing method in strain-controlled mode. This paper looks at how the loading frequency impacts Wohler's law parameters (slope and intercept) of a high modulus asphalt concrete (HMAC) made with a polymer-modified bitumen. Under strain-controlled mode, Tensile-Compression tests (TC) on cylindrical samples were carried out at isothermal conditions (theta = 10 degrees C) and three distinct frequencies (5, 10 and 25 Hz). The analysis of covariance (ANCOVA) was considered to compare Wohler's law parameters from different frequencies. The results showed no statistical difference in the slope and the intercept values from all studied frequencies.