Pavement performance evaluation of low penetration asphalt binder in southern cities

Asphalt pavement is the mostly used pavement type for city streets. Its conditions and performance are critical to ensure the adequate capacity and efficiency of city traffic. Since the Chinese asphalt binder specification is penetration-based grading system, which does not provide a clear correlation with environment condition, the selection of the binder for a paving project is primarily according to local construction experience. As the rapid expansion of the traffic volume in cities, previous experience could not meet the changing demand. Severe pavement distresses could be observed on streets at the time, which is much earlier than the designed pavement life, especially near city logistics transport centers. This paper presents a study on evaluation of low penetration asphalt binder from the perspective of pavement performance at high and low temperature. Four types of binder were collected. All of them were tested according to Chinese binder specification. Further, dynamic shear rheometer (DSR) and bending beam rheometer (BBR) were used to characterize the performance of binder at high and low temperature range respectively. Rutting resistance of HMA manufactured with four types of binder were evaluated using wheels load tester at both 60℃ and 70℃. The thermal crack resistance of HMA were also evaluated and the thermal stress restrained specimen test (TSRST) were used to capture the cracking temperature. The results show that, the low penetration asphalt binder possesses the better high temperature performance, meanwhile their low temperature performance satisfies the pavement requirements in southern cities of China.