This study addresses the severe durability challenges for asphalt pavements in extreme, arid continental climates like Turpan, Xinjiang, where summer surface temperatures exceed 80 °C and winter lows drop below −20 °C. It evaluates Qingchuan rock asphalt (QRA) as a modifier to enhance the durability of plant-mixed hot recycled asphalt mixtures containing reclaimed asphalt pavement (RAP). Laboratory tests at binder and mixture levels evaluated the performance of QRA-modified binder and recycled mixtures. The program included binder specifications, performance grading, dynamic modulus, dynamic stability, and residual stability. Results indicate that increasing QRA dosage raises the softening point, G*/sin δ, and high-temperature PG, enhancing stiffness and rutting resistance. Although blending with RAP binder further improves high-temperature performance, it reduces workability and low-temperature resistance. In mixtures, dynamic stability, residual Marshall stability, and TSR increased by 115%, 6.59%, and 14.38%, respectively, while failure strain decreased by 30.8%. Dynamic modulus master curves confirm improved modulus retention at high temperatures. Considering the local PG 76–22 requirement and relevant specifications, a mixture containing 10% QRA and 50% RAP is recommended for durable plant-mixed hot recycled asphalt pavements in Turpan and similar arid climate regions.
Zhao et al. (Fri,) studied this question.