Investigation on the fatigue resistance of hot thin asphalt concrete modified by nano-silica

This research aims to investigate the fatigue life resistance of hot thin asphalt concrete modified by nano-silica at intermediate temperature (20oC). In this research, 5% wt. of nano-silica was added to the bitumen. The tests, including penetration degree, softening point, and four-point beam fatigue test was conducted to evaluate the modified asphalt concrete. The results showed that adding nano-silica reduce penetration degree and increase kinematic viscosity of the bitumen. The results of the four-point beam fatigue test showed that the addition of nano-silica had increased fatigue life. Overall, the addition of nano-silica resulted in the decrease of fatigue cracks, an average increase of about 73.1 % in 3 level strain of fatigue life and fatigue resistance of hot thin asphalt concrete at intermediate temperature.