Influence of Asphalt-Binder Content on The Hydraulic and Mechanical Performance of A Permeable Friction Course Using Multi-Criteria Analysis

Abstract

Most construction standards specify the asphalt-binder content for Permeable Friction Course (PFC) mix based on functional parameters, such as air voids (AV), and durability (Cantabro Loss CL). However, these standards do not account for parameters that assess the mixture's mechanical behavior. This study integrated the evaluation of mechanical and hydraulic performance, along with a multi-criteria analysis using the analytic hierarchy process (AHP), of a PFC mixture in the laboratory, testing asphalt contents of 4.5%, 5.0%, and 5.5%, modified with crumb rubber (CRM) (percentage of the total mixture mass). Hydraulic properties (AV and permeability coefficient), durability (CL at 25°C and 60°C), and mechanical characteristics were evaluated through indirect tensile strength (ITS), Resilient Modulus (RM), tensile strength ratio (TSR), and static creep test. An analysis of variance (ANOVA) was conducted to determine whether differences in results were significant. Additionally, AHP was employed to identify the optimal asphalt content based on laboratory test outcomes. The findings suggest that, following traditional construction standards in Colombia, the asphalt-binder content for the PFC mix should be 5.0%. Nevertheless, the multi criteria analysis based on the proposed methodology indicates that an asphalt-binder content of 5.5% provides better performance. Although this increase entails higher costs, it considerably improves the pavement's durability.