Fatigue performance of bituminous mixtures made with recycled concrete aggregates and waste tire rubber

Fatigue cracking is one of the main hot-mix asphalt (HMA) failure modes. The current laboratory investigation analyses the fatigue performance of HMA made with recycled concrete aggregates (RCA). An HMA type AC 22 bin S made with 0%, 35% and 42% of RCA was tested in the indirect tensile fatigue test (ITFT) device. Three constant stress levels, ranging from 150 kPa to 350 kPa were used. Mixtures were manufactured at the optimum bitumen content using two types of bitumen: a B35/50 penetration grade bitumen and a 10% waste tire rubber modified bitumen, BC35/50. This investigation demonstrates the beneficial effect on fatigue life of the incorporation of RCA. Additionally, the use of crumb rubber could lead to RCA bituminous mixtures with higher fatigue life in medium traffic roads.