Assessment of Mechanical and Durability Characteristics of Bituminous Mixtures with Recycled Asphalt Pavement and Jhama Brick Aggregate: Simplified Approach

Abstract This study investigated the use of reclaimed asphalt pavement (RAP) and Jhama brick aggregate (JBA) in asphalt concrete (AC) mixtures, with basalt aggregate (BA) as the primary base material, and developed an equation to adjust the proportions of RAP aggregate and RAP binder for the bituminous mix preparation. RAP was combined with JBA to achieve the required gradation, and the aged binder in RAP was rejuvenated using viscosity-grade bitumen, specifically VG20 and VG30. The aim was to develop a high-performance, sustainable AC mix incorporating the RAP, JBA, and fresh binders. Optimal blending ratios for VG30:RAP binder and VG20:RAP binder were found to be 65∶35 and 55∶45 , respectively, based on penetration and rheological evaluations. The modified RAP mixtures demonstrated notable enhancements in mechanical performance, with Marshall stability increased by 12.45% and 19.07%, respectively, compared with that of the control mix. Incorporating the JBA into the RAP-modified mixes further improved the results with respect to the modified Lottman test, resilient modulus ratio (RMR), indirect tensile strength (ITS) across different temperatures, and resistance to the rutting and fatigue. Life-cycle cost and carbon footprint analyses demonstrated significant cost savings and reduced greenhouse gas emissions compared with the control mix. The outcomes highlight the effectiveness of RAP and JBA as cost-efficient, environmentally friendly alternatives for durable and reliable pavement construction.