Abstract:In rainy weather, the probability of traffic accidents in the ultra-high transition section of expressway is obviously higher than that in other road sections. In order to explore the causes and put forward the corresponding countermeasures, by studying the traffic accident data of an expressway in a rainy area along the coast of South China, the time, form and spatial distribution of the accidents are sorted out and analyzed. It is found that the pavements in the ultra-high gradient section are easily formed of the thicker water film, which is complexly distributed. Therefore, the sideslip of vehicle caused by the reduction of the anti-skid ability of pavement is one of the important reasons for the accidents. The characteristics of the plane distribution and thickness distribution of the water film are simulated and analyzed from the factors of longitudinal slope and ultra-high gradient. And the improvement measures are proposed to provide a technical reference for improving the driving safety of the ultra-high transition section in rainy days.
