Comparative Study of the Effects of Nanosilica and Zyco-Soil Nanomaterials on the Properties of Asphalt Concrete

Abstract

Recent studies have revealed that zyco-soil and nanosilica are among the nanomaterials that can help improve the moisture-damage resistance of asphalt mixtures. However, these also affect the properties of asphalt mixtures in different ways. For the first time, this study aims to compare their effects on some engineering properties of a typical asphalt concrete, the environmental impact, and the cost. The 60/70 penetration-grade asphalt cement was modified by adding different percentages of nanosilica (1, 3, and 5%, by the weight) and zyco-soil (0.1, 0.3, and 0.5%) content and evaluated using experiments. The results showed that nanosilica modification leads to higher resistance to permanent deformation, resilient modulus, and indirect tensile strength compared with zyco-soil modification. Beyond an optimum zyco-soil content of 0.1%, resistance to permanent deformation and resilient modulus of the mixtures decreases with increasing zyco-soil content. The results also showed that zyco-soil-modified asphalt mixtures are more resistant to moisture damage compared with the nanosilica-modified mixtures. However, the optimum zyco-soil content to achieve the highest resistance to moisture damage is different from that used to achieve stiffness and stability. For nanosilica, the optimum content to achieve the highest resistance to moisture damage and stability is the same.