Performance of SBS modifier-crumb rubber composite modified asphalt used as an anti-wear layer of perpetual pavement

Abstract

ABSTRACT Perpetual pavement has become an important research area of highway development in China. Ensuring the durability of materials is an essential measure to achieve the goal of perpetual pavement construction. This paper documents a study on how to prepare SBS modifier/crumb rubber composite-modified asphalt (SRA) by testing based on an orthogonal experimental design to obtain the optimum proportion of crumb rubber, SBS modifier, and compatible stabiliser. We used needle penetration, ductility, softening point, 60°C dynamic viscosity and segregation as evaluation indexes to obtain optimal ratios. Then, we analysed the performance of SRA and compared it with that of other asphalts, such as base asphalt, SBS-modified asphalt, rubber asphalt and high-viscosity-modified asphalt. We considered that rubber powder and SBS modifier compound-modified asphalt can form a cross-linked stable structure in asphalt and greatly improve the rheological and antifatigue properties of asphalt. Further, we conducted a comparative experiment to study the performance of asphalt mixtures, and we concluded that SRA has better road performance and can be used as an anti-wear layer of perpetual pavement.