A systematic review of the performance durability and sustainability of sugarcane bagasse ash as a mineral filler in asphalt mixtures

The increasing demand for sustainable pavement materials has stimulated interest in sugarcane bagasse ash (SCBA) as an alternative mineral filler in asphalt mixtures. This systematic review critically evaluates the mechanical performance, durability, and sustainability of SCBA-modified asphalt mixtures following the PRISMA 2020 framework. Relevant studies published between 2012 and 2026 were retrieved from Scopus, Web of Science, ScienceDirect, and Google Scholar, screened using predefined eligibility criteria, and assessed for methodological quality. To ensure valid interpretation, the evidence was classified into direct SCBA-as-filler studies, bagasse-fiber systems, SCBA-derived bio-oil applications, hybrid SCBA–nano-silica semi-flexible mixtures, and non-asphalt background studies. Quantitative synthesis was restricted to directly comparable SCBA-as-filler studies. The findings indicate that approximately 5–8% SCBA by mass of filler generally provides the most favorable performance. Within this range, Marshall stability increased by approximately 12–20%, including a reported increase from 7.6 to 9.0 kN (18.4%), while indirect tensile strength improved by approximately 8–18%, including an increase from 0.95 to 1.12 MPa (17.9%). SCBA also enhanced mixture densification and moisture resistance and generally reduced air voids. Larger improvements reported for hybrid semi-flexible mixtures, including an 88.5% increase in Marshall stability and a 70% reduction in rut depth, cannot be attributed to SCBA alone. Performance enhancement is primarily governed by particle packing, filler–binder absorption, and mechanical interlocking rather than pozzolanic reactions within the bituminous phase. SCBA can reduce reliance on quarried fillers and promote waste valorization; however, its environmental benefits depend on transportation requirements and processing energy. Evidence remains insufficient regarding long-term ageing, fatigue, low-temperature cracking, rheological behaviour, field performance, and life-cycle impacts. Standardized processing, performance-based characterization, comprehensive environmental assessment, and full-scale field trials are therefore required to support practical implementation.