Emulsion Mixtures of Fractionated Reclaimed Asphalt Pavement and Quarry By-Products: A Laboratory Evaluation

Abstract

Emulsion aggregate mixtures (EAMs) are aggregate blends stabilized with an asphalt emulsion for pavement base layer applications. These are typically prepared using crushed aggregates and designed primarily using a tensile strength-based criteria. Advances in granular material testing technologies have led to the development of advanced resilient response characterization devices such as the University of Illinois FastCell (UI-FastCell). Simultaneously, fractionated reclaimed asphalt pavement (FRAP) and Quarry by-product (QB) materials are becoming increasingly common in pavement construction. This paper evaluates the inclusion of QB and FRAP in EAMs. First, the design of selected EAMs was performed using a combined Asphalt Academy TG2 and Anderson and Thompson mixture design approach. The selected mixtures were first assessed for Indirect Tensile Strength (ITS) and Tensile Strength Ratio (TSR) to track changes in both strength and moisture damage resistance with the inclusion of FRAP and QB. In addition, advanced anisotropic resilient characterization was performed using the UI-FastCell to assess the changes in resilient modulus and permanent deformation characteristics. Our results show significant enhancements in tensile strength, increased moisture damage resistance, and reduced permanent deformation with the inclusion of FRAP and QB materials in EAMs. The combined inclusion of 30% FRAP and 70% QB negatively affected the resilient response of the EAM; however, the inclusion of FRAP content to 50% with no QB materials improved its suitability for pavement base layer application.