Open-graded asphalt concrete grouted by latex modified cement mortar

Abstract

In order to improve the anti-rutting ability of grouted open-graded asphalt concrete (GOAC) for semi-flexible pavement, latex modified cement mortar was introduced in this study. A comprehensive performance evaluation was carried out to study the viability of the GOAC with latex modified cement mortar. The asphalt skeleton gradation was determined by adopting the GOAC experience in Japan. The asphalt skeleton was designed based on porosity, strength and runoff resistance, while the latex modified cement mortar was designed based on fluidity, flexural strength and compressive strength. The results showed that the addition of the latex can significantly improve the 7-day flexural strength while only slightly compromise the fluidity. A grouting saturation degree of higher than 96% was found for the GOAC-13 and GOAC-16. The performance of the latex modified GOAC was compared with conventional asphalt concrete. It was found that the GOAC has significantly better rutting resistance, but the moisture susceptibility, low-temperature crack resistance and fatigue performance were weaker. However, the results also showed that the moisture susceptibility and the low-temperature performance for the latex modified GOAC were at acceptable levels. In addition, it was found that the Marshall immersion test is not suitable for evaluating the moisture susceptibility of GOAC in comparison with the freeze–thaw conditioning method.