A Performance-Based Design Framework for Enhanced Asphalt Concrete in the Caribbean Region

Abstract

The majority of recent research in has been focused on the introduction, development, and evaluation of performance-based specifications for the design of asphalt concrete mixtures. In the Caribbean, most laboratories only use the Volumetric Marshall Mix design methodology. Road designers, engineers, consultants, and contractors have all highlighted the many shortcomings and inadequacies of the volumetric design mix selection process. The consensus is that there is a need to a develop process that addresses the service’s performance and common distress on asphalt pavements through performance-based mix design. Performance-Based Mix Design (PBMD) has been used as a practical alternative to the volumetric mix design technique in evaluating pavement distresses by incorporating performance testing in conjunction with volumetric parameters into the mix design process. This study describes the findings of our comprehensive laboratory research, which was conduced to facilitate the development of a Performance-Based Mix Design framework for asphalt concrete mixtures. The research methodology involved the collection and integration of qualitative and quantitative data through case studies and experimental work. Two control and two PBMD mixtures were designed to evaluate both the volumetric and performance properties that address distresses of permanent deformation (rutting), fatigue cracking, stiffness, and moisture susceptibility. The PBMD framework led to the development of performance test criteria for permanent deformation, stiffness modulus, fatigue cracking, and an acceptable tensile strength ratio. The development and implementation of the PMBD framework for the Caribbean region could exemplify a significant step towards achieving sustainable asphalt pavements in the region. The framework, which incorporates best-practice solutions, is anticipated to increase awareness about the variables that affect the performance of asphalt mixtures.