Experimental study on the low-temperature performance and evaluation methods of crack sealants for asphalt pavements in seasonal frozen regions

Road repair materials employed in the seasonal frozen regions of Northeastern China always often demonstrate poor long-term performance under extreme climate conditions. This is primarily attributed to the detrimental effects of short-term aging and frequent freeze-thaw cycles on the adhesive properties of sealants. Existing standards fail to adequately account for these complex environmental factors, leading to unsatisfactory repair outcomes. This study evaluated the changes in adhesive performance of eight commonly used sealants under conditions simulating short-term high-temperature aging, low-temperature water immersion, and repeated freeze-thaw cycles. The mechanical properties of the materials under different conditions were assessed using low-temperature tensile tests and an improved energy dissipation method. The results indicated that short-term high-temperature aging caused a significant reduction in the adhesive strength of the sealants, while freeze-thaw cycles further exacerbated performance degradation. Conversely, low-temperature water immersion improved adhesive strength by 48.1%. Compared to conventional assessment methods, the improved energy dissipation method provided a more precise evaluation of changes in adhesive performance under complex environmental conditions. This study offers valuable theoretical insights for the selection and optimization of repair materials in cold regions and addresses limitations in current standards.