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Water film thickness is of great significance to the skid-resistant performance of an asphalt runway. Obtaining the precise information of water film thickness can help to assess the skid resistance with higher accuracy. This article proposes a wide-area dynamic sensing method of water film thickness on asphalt runway. The model, considering precipitation time-variability, runway geometry, and runway surface characteristics, is established to extract spatial temporal information of water film thickness dynamics on runway during intense rainfall. The model optimization is further conducted to deal with the problems of slope change, singularity issue, and time-spatial evolution of water film, which extends the single-point water film sensing to the large-area sensing. In order to evaluate the developed method, the calculations of water film thickness from the model are compared with the results obtained from a laboratory rainfall simulation experiment. The results show that the method has high accuracy in sensing the water film thickness and can realize a dynamic and whole-area acquisition of runway wet surface condition information. This method can provide data support for intelligent decision making of landing safety under rainfall conditions.

The interface bonding between Portland cement concrete (PCC) pavement and hot-mix asphalt (HMA) overlay plays an important role in the performance of the composite pavement. This research conducted a series of comprehensive laboratory studies to investigate the influence factors of the interface bonding strength using a self-designed direct shear test apparatus that can simultaneously apply normal stress and shear stress on a specimen. Four kinds of commonly used tack coat materials were systematically tested and compared under various combinations of normal stress and temperature. Then, coupling effects of the normal stress and temperature on the interface bonding between PCC and HMA were analyzed. The test results show that temperature has a significant impact on the adhesion of the tack coat. Emulsified asphalt was considered the optimal tack coat material because of its simple construction method. In addition, it was found that a damaged interface could still provide considerable bonding strength. Normal stress generated by traffic loads was beneficial to the interface bonding strength, especially at lower temperatures. The temperature had a significant effect on interface bonding and played a leading role in the failure mode of interface bonding.