Performance Characterization of CR/PU Asphalt for Potential Application in Assembled Fast-Repairing Engineering

Abstract

Conventional repairing methods for asphalt pavement have some inconveniences, such as insufficient strength, and are typically time-consuming. To address these issues, this study proposes a new technological method to design and prepare a high-performance assembled asphalt concrete block for fast repair of the potholes. A series of composite modified asphalt binders with 10% crumb rubber (CR) and different dosages (0%, 1%, 3%, 5%) of polyurethane (PU) are examined to determine the optimized binder. Subsequently, the corresponding asphalt mixtures are prepared for further comparison and assessment of engineering properties, such as moisture-induced damage, high-temperature deformation, and low-temperature cracking characteristics. The test results show that PU can significantly improve the high-temperature performance and hardness of (crumb rubber modified asphalt) CRMA binder; 3% PU contributes allowing the resistance of CRMA mixture to moisture-induced damage at higher levels, particularly under water whole immersion; as 3% PU is added, the high-temperature rutting deformation resistance of the CRMA mixture increases significantly, and the low-temperature anti-cracking properties are also improved slightly. Therefore, the innovatively designed high-quality assembled fast-repairing asphalt concrete block is recommended as an appropriate option for highway maintenance.