Evaluation of Emulsion-Based Warm Mix Asphalt Using Marshall Mix Design

This study evaluates the extended performance and environmental benefits of Warm Mix Asphalt (WMA) prepared using a medium-setting bitumen emulsion and VG 30 binder. Building on prior mix design optimization, this work investigates moisture susceptibility and tensile strength performance across varying conditions. Indirect Tensile Strength (ITS) tests were conducted at 5°C to 40°C and showed that mixes with a 70:30 bitumen-emulsion ratio at 120°C achieved a peak ITS of 1.14 MPa at 25°C. Tensile Strength Ratio (TSR) values exceeded 80%, indicating strong resistance to moisture damage. Retained Stability tests confirmed the durability of the mix with a value of 85.6%, well above the minimum threshold. Additionally, fuel efficiency analysis for a hypothetical pavement section demonstrated a 25–30% reduction in diesel consumption when using WMA instead of HMA. This translated to a 28% reduction in CO₂ emissions per ton of mix. These findings reinforce the potential of emulsion-based WMA as a technically viable and environmentally superior alternative for sustainable pavement construction in India.