A Unified Sustainability Framework for Next-Generation Pavements and Structural Materials: Integrating RHA Concrete and WMA Additive Technologies

The construction and transportation sectors are under growing pressure to reduce carbon emissions and improve material sustainability. This study evaluates the combined sustainability potential of Rice Husk Ash (RHA) concrete and Warm Mix Asphalt (WMA) and proposes a unified framework for assessing next-generation pavement and structural materials. Four concrete mixes with 0–30% RHA replacement and three asphalt mixes incorporating chemical and organic WMA additives were tested for mechanical performance, durability, and environmental impact. Results show that 20% RHA (C20) achieved the highest compressive strength (49.2 MPa), representing a 15.8% improvement over the control, while also reducing chloride penetration by 42% and embodied carbon by 20%. For asphalt, the organic WMA2 mix reduced production energy by 27.1%, improved tensile strength ratio (TSR = 88.2%), and enhanced rutting resistance by 17.5% compared to Hot Mix Asphalt. Statistical analyses, including ANOVA and regression modeling, confirmed the significant influence of RHA content and temperature reduction on performance and sustainability outcomes. A Unified Sustainability Score (USS) integrating mechanical, durability, and environmental metrics identified C20 + WMA2 as the most sustainable system (USS = 0.91). The study demonstrates that integrating RHA concrete and WMA technologies provides a viable pathway toward low-carbon, durable, and performance-optimized infrastructure. The unified framework offers a robust tool for engineers and policymakers to guide sustainable material selection and future infrastructure development.