Abstract Manager

Lightweight and thermally insulating pavement materials have been traditionally used in specialized pavement construction applications to address challenges posed by extremely weak/collapsing and frost susceptible subgrade soils, respectively. However, incorporation of these materials is typically limited to granular pavement layers rather than bound asphalt concrete courses. This study presents a novel asphalt concrete mixture that was developed through partial replacement of the conventional aggregate skeleton with Foam-Glass Lightweight Aggregate (FG-LWA) as synthetic lightweight aggregates (SLA). The SLA used in this study exhibits high strength, low absorption, and considerable thermal insulation which makes it ideal — as compared to its existing counterparts— for asphalt concrete production purposes. The modified SuperPave mix design process is discussed to account for SLA incorporation and its impact on the subsequent design metrics. Furthermore, a battery of experiments including IDEAL-CT, Hamburg Wheel Track Testing, and Semi-Circular Bending (SCB) testing was employed to evaluate the expected performance of this innovative mixture at the laboratory scale. The reduction in bulk density and enhanced thermal insulation characteristic of the developed mixture are shown to be promising, highlighting its potential for further investigation. This technology is expected to alleviate the need for soil removal activities and equipment, which may ultimately help minimizing project completion time and cost for pavement construction in applications with problematic subgrade soil conditions.