Work

Mechanistic Review on Moisture Damage Susceptibility of Warm Mix Asphalt with Reclaimed Asphalt Pavement

Year: 2026

Type: article

Abstract: Warm mix asphalt (WMA) provides a sustainable way of lowering production temperatures, reducing energy use for sustainable pavement construction; however, moisture damage affects its durability. Reclaimed asphalt pavement (RAP) contains aged binder that is stiffer, harder, and more brittle than virgin binder, resulting in asphalt mixtures with higher stiffness/modulus. This review examines the effect of incorporating RAP to amend the moisture damage susceptibility of WMA. It surveys the various moisture-damage failures reported in the literature on WMA with RAP mixes, including adhesive and cohesive failures, as well as hydraulic scouring and aggregate fracture. The analysis further explains the influence of WMA technology, RAP content, rejuvenation, and interfacial chemistry on the moisture durability of WMA-RAP mixtures. The strengths and limitations of the conventional and emerging moisture damage evaluation tests, including AASHTO T 283 tensile strength ratio (TSR), boiling water test (BWT), surface free energy (SFE), and fracture-energy-based approaches, were compared. This mechanistic synthesis linking production-related moisture sources, RAP heterogeneity and practical mitigation strategies highlights why reliance on TSR alone can conceal moisture-cracking vulnerability. The synthesis clarifies how RAP changes the moisture damage susceptibility of WMA to retain the environmental, economic and social benefits and circularity without compromising durability. This review proposes a practical roadmap based on technology-specific screening, multi-metric performance evaluation, and construction quality control for more reliable WMA-RAP specifications.

Source: Eng—Advances in Engineering

DOI: 10.3390/eng7070349

Authors: Suleiman Abdulrahman, Sadi Ibrahim Haruna, Yasser E. Ibrahim, Nura Shehu Aliyu Yaro, Abdulwarith Ibrahim Bibi Farouk

Institutions: King Fahd University of Petroleum and Minerals, Prince Sultan University, Ahmadu Bello University, Durban University of Technology

Language: English

Topic: Asphalt Pavement Performance Evaluation

Subfield: Civil and Structural Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Responsible consumption and production, Climate action

Open Access status: gold

Estimated APC paid: $1,448