Evaluation of Fatigue and Rutting Behaviour of Hot Mix Asphalt Containing Rock Wool

The objective of this study is to evaluate the effects of adding rock wool fibres on the improvement in the dynamic properties of the hot mix asphalt. To this aim, the effects of 0.2, 0.4, 0.6, and 0.8 of percent rock wool fibres by weight of mixture on the dynamic properties of asphalt mixtures were evaluated. Accordingly, indirect tensile stiffness modulus, indirect tensile fatigue and repeated load axial tests were performed to measure the stiffness modulus, fatigue life and rutting resistance of asphalt mixtures. The fatigue life of modified mixtures with different concentrations of rock wool increased 4%, 32%, 35% and 65% at 25 °C with regard to control, respectively. Furthermore, adding 0.8% of Rockwool resulted in 84% and 130% increased in resistance to permanent deformation at the stress of 150 kPa and 300 kPa, respectively. Consequently, incorporation of rock wool in asphalt mixture can be beneficial as it enhances the performance of road pavements against distresses such as rutting and fatigue cracking.