Buton Rock Asphalt (BRA/Asbuton): a systematic review of the characteristics, performance, sustainability, and future research directions

Conventional petroleum-based asphalt binders raise environmental concerns due to high energy use and greenhouse gas emissions during production and application. As a more sustainable option, Buton Rock Asphalt (BRA) a natural asphalt from Buton Island, Indonesia offers potential to improve pavement performance while reducing environmental impact. This review synthesizes 198 studies (1983-2024) to examine BRAs characteristics, including its geological origin, chemical composition, and mineral content. In terms of performance, BRA enhances rutting resistance, stiffness, fatigue life, and aging due to its high asphaltene and resin content and strong oxidative stability. However, its porous ash and high mineral content may increase brittleness and reduce low-temperature performance. From a sustainability perspective, BRA supports reduced petroleum use and enables integration with bio-oils, RAP, SBR, and other modifiers. Despite its advantages, further research is needed to address raw material variability, expand long-term field validation, and strengthen assessments of environmental and circular economy benefits. © 2025 Informa UK Limited, trading as Taylor & Francis Group.