The effects of hollow glass microsphere modification on the road performances and thermal performance of asphalt binder and mixture

Abstract

High temperature in asphalt pavements often leads to rutting of asphalt pavements and heat island effects in urban areas. In this study, to improve the thermal resistance of asphalt pavement, hollow glass microspheres (HGM) modified asphalt and HGM/Styrene-Butadiene-Styrene (SBS) modified asphalt were used to prepare asphalt concrete (AC) and stone mastic asphalt (SMA) respectively. The effects of HGM on the penetration, ductility, softening point and rheological properties of asphalt binder and the cooling performance, mechanical property, high temperature stability, low temperature resistance, water stability and other properties of asphalt mixture were investigated. Finally, the composition of the thermal resistance surface layer was recommended. Results showed that, adding HGM increased the high temperature stability of both matrix asphalt and SBS modified asphalt while the low temperature performance of both the two types of asphalts decreased. For the asphalt mixture, the addition of HGM improved the cooling performance of the AC-13 mixture but had no effect on the cooling performance of the SMA-13 mixture. HGM also showed positive effects on the pavement performance of the asphalt mixtures. For the AC-13 mixture, it improved the mechanical property, high-temperature stability, low-temperature cracking resistance and immersion residue stability but had no effect on the thaw-splitting strength ratio (TSR). For the SMA-13 mixture, it improved the Marshall stability, high-temperature stability, immersion residue stability, scattering resistance while impaired the low-temperature crack resistance, TSR and anti-drainage ability. Finally, it was recommended to use 5% HGM modified AC-13 mixture as the thermal resistance surface layer.