Equivalence evaluation of rutting modified asphalt mortar with high elastic resistance to asphalt and mixture

Aiming at the aggravated rutting distress of asphalt pavement under heavy-load traffic and persistent high-temperature service conditions, and breaking through the limitations of low efficiency, high cost and coarse aggregate interference in traditional anti-rutting additive evaluation systems, this paper proposes a mortar-scale rapid and accurate equivalent evaluation method for high-elastic anti-rutting additives. Three high-elastic anti-rutting modifiers (NAR, UAR, AAR) were used to prepare modified asphalt, asphalt mortar and asphalt mixture specimens under equivalent asphalt-aggregate ratio and consistent gradation. The high-temperature recovery, low-temperature relaxation and fatigue resistance of mortar were characterized by multi-stress creep recovery, low-temperature relaxation and linear amplitude sweep tests based on dynamic shear rheometer, and the multi-scale correlation and cost-benefit analysis were verified with asphalt and mixture tests. The results show that the key rheological parameters of asphalt mortar are highly linearly correlated with the road performance of mixture, with all Pearson correlation coefficients exceeding 0.90, which is significantly better than the asphalt-scale evaluation. The non-recoverable creep compliance, relaxation modulus and fatigue life of mortar can accurately characterize the rutting resistance, low-temperature crack resistance and fatigue durability of mixture. Compared with the conventional mixture-scale evaluation, this method shortens the test period by 64% and reduces the material consumption by 99.7%, and effectively eliminates the interference of coarse aggregate. This research provides an efficient, economical and reliable technical solution for the rapid screening and performance optimization of high-elastic anti-rutting additives in pavement engineering maintenance and new construction.