Using polymer-based mixes as alternative to asphalt mixes in low volume roads

Abstract

This study explores the use of a water reacting polymer as a substitute to asphalt binder in constructing pavement wearing surfaces for mitigating environmental impacts (e.g., carbon emissions and urban heat island effects). The alternative asphalt binder used in this study is AP Soil 600, which is a pre-activated polymer that reacts with water. One of the advantages of a polymer-based pavement is reduced heat absorption that could effectively reduce pavement temperatures as well as the reduction in emissions of greenhouse gases (such as CO2) during and after construction. The natural color of the polymer is light brown, which has higher albedo than asphalt concrete and as a result reflects more of the solar radiation that falls on the pavement. This study presents a methodology to design the mix constituents, polymer, and water content including the optimum curing and compaction processes. Performance testing was conducted to evaluate the polymer-based mixes’ mechanical strength under compression, indirect tension, and resistance to rutting as compared to conventional asphalt mixes. The impact of curing process of the polymer samples on the unconfined compressive strength, indirect tensile strength, and rutting were comparatively evaluated. The results indicated that polymer-based mixes can meet the demand for low volume road construction considering their relative easy workability, increasing strength in dry conditions, and environmental benefits.