Experimental Study on Water Damage Resistance of Permeable Asphalt Mixture Under Coupling Action of High Temperature and Rainwater

Permeable asphalt road surfaces have gained prominence in China's green road initiatives, finding widespread application. To investigate the extent of water-induced deterioration of permeable asphalt mixtures under high-temperature rainfall coupled conditions, this study employed Hamburg Wheel Tracking (HWT) tests. Six environmental conditions were established, encompassing dry, saturated, and submerged states at temperatures of 50°C and 60°C, denoted as Conditions 1 (50°C, dry), 2 (50°C, saturated), 3 (50°C, submerged), 4 (60°C, dry), 5 (60°C, saturated), and 6 (60°C, submerged). Various performance indicators, including rut depth, rut deformation rate, creep rate, and stripping inflection point, were measured to evaluate the water damage resistance of permeable asphalt mixtures under different environmental conditions. The results revealed a significant decrease in all assessed indicators under high-temperature rainfall coupled conditions, suggesting a substantial reduction in water damage resistance. Notably, under dry, saturated, and submerged conditions at 60°C, the maximum rut depths were 1.95, 2.54, and 2.60 times those observed at 50°C, respectively. The rut depths exhibited a ratio of 1:1.2:2.2:1.9:3.1:5.8 for the conditions of 50°C dry, 50°C saturated, 50°C submerged, 60°C dry, 60°C saturated, and 60°C submerged. The rut deformation rate ratios followed a pattern of 1:1.2:2.2:1.9:3.1:7.2, while the creep rate ratios were 2.4:2.2:1.2:1.3:1.1:1, and the stripping inflection point ratios were 2.5:2.25:1.25:1.75:1.25:1 for the same conditions. This study underscores the significant influence of high-temperature rainfall coupling on the water damage resistance of permeable asphalt mixtures. The research outcomes, validated through Hamburg Wheel Tracking tests, provide theoretical foundations and technical support for the development and application of green road systems.