Volume 40, Issue 7 (December 2012)
Investigation into High-Temperature Stability of Asphalt Pavement
To identify potential causes of the unstability problems of asphalt pavement at high temperature, effects of reinforced fiber, asphalt content, and temperature on the stability were analyzed using the wheel tracking test, the triaxial repeated load test (TRT), and partial triaxial test (PTT). The results indicated that Sup19 shows a better rutting resistance and lower permanent deformation than that of AC20, and the polyester fiber has significantly improved the rutting resistance of asphalt mixtures. The asphalt content affects greatly the mixture deformation. PTT method is more sensitive to asphalt content change. High-temperature facilitates to reduce the viscosity of asphalt binder and internal friction between the aggregate particles, resulting in permanent deformation. And most permanent deformation occurs at the first loading cycles because of densification followed by a slight increase in permanent deformation owing to plastic flow. It is concluded that the asphalt content and mixture compaction should be controlled strictly during construction, and fiber can improve the resistance to rutting in pavement, and PTT method can better understand dynamic properties of asphalt mixtures.