Salt release and performance of self-ice-melting epoxy asphalt pavement under accelerated loading simulation conditions

To evaluate the salt release and road performance of self-ice-melting asphalt pavements under the environment-load coupling, this study aims to determine the ice melting, road performance, and the internal void structure of self-ice-melting asphalt pavements under accelerated loading simulation conditions. First, an indoor accelerated loading simulation (rainfall, loading, rain-load coupling) test system (ALSTS) was established, and 1.2 million cyclic loading tests were carried out on ordinary and self-ice-melting epoxy asphalt pavements. Then, the conductivity measurement test, freezing force test, and ice melting test were determined under different salt release conditions. Furthermore, the laser rutting instrument, pendulum friction meter, and Universal Testing Software (UTS) were used to determine the evolutionary patterns of rutting depth, skidding resistance, and dynamic modulus. Finally, the change law of the internal pore structure was determined by CT tomography and image processing technology. The results show that the coupling accelerated the release of salt from the self-ice-melting asphalt pavement, which exacerbated the decay rate of its road performance. Compared with the individual impact of rainfall, the coupling increased the salt release by 47.9∼71.2 % and shortened the de-icing life by 7.3∼13.3 %. Adding epoxy asphalt mitigated this adverse effect, which slowed down road performance decay, increased the fatigue life by 50.5∼104.8 %, and extended the de-icing life by 14.1∼33.9 %. Adding epoxy asphalt effectively inhibited the growth of internal voids and the creation of connected voids in the specimen, improving the fatigue resistance of self-ice-melting asphalt pavement by the CT image analysis.