Research on the high temperature performance of asphalt pavement based on field cores with different rutting development levels

Rutting is one of the main distresses of highway asphalt pavement in China. Evaluating the high temperature performance of asphalt pavement during its service period is a major problem for road management departments. The purpose of this paper is to investigate the effect of rutting development levels on the high temperature performance of each layer in asphalt pavement and provide guidance for rutting distress evaluation of highway asphalt pavement. The field cores were obtained from the sections with different rutting development levels (different Equivalent Single Axle Loads and rutting depths) under the same service life. Based on the thickness measurement of field cores, the rutting contribution rate (RCR) of each layer was calculated. Dynamic creep test was performed on the surface layer SMA-13 and binder layer SUP-20 mixtures. Finally, dynamic modulus test was conducted to analyze the influence of rutting development levels on the viscoelastic properties of the binder layer asphalt mixture. The results show that the surface layer is largely responsible for the rutting in the initial rutting stage (rutting depth is less than 10 mm), the RCR of the binder layer increases gradually and exceeds that of the surface layer as the rutting develops. For the selected pavement structure, when the rutting depth of whole pavement is more than 15 mm, the binder layer SUP-20 behaves more like viscoplastic body in high-temperature/low-frequency range. The RCR value of binder layer is more than 40% and its resistance to deformation at high temperature starts to degrade rapidly. The high temperature performance of the surface layer remains relatively stable under different rutting depths.