Abstract: Abstract:Aimed at the fact that instantaneous dynamic water pressure caused by tires is the main reason for water-damage of pavement materials and skid of vehicle that may be endanger the safety of the vehicle in rainy condition. In order to explore the risk speed of water-skidding and the water-damage process of the pavement material subjected to the dynamic water erosion. In this paper, the Audi A4L and Shaanxi Auto Catron F3000 as the main research object, and the AH-E type instantaneous dynamic water pressure sensor was used to measure the instantaneous dynamic water pressure data of the two vehicles under the condition of different driving speeds on the cement concrete road surface, and based on the COMSOL Multiphysics software platform, the fluid structure interaction analysis model of the tire-water film-road surface interaction was established. This model was used to analyze the regularity of the influencing factors of instantaneous dynamic water pressure on the road surface, and calculate the risk velocity of water-skiing. The results show that the instantaneous dynamic water pressure on the road surface increases with the increase of the thickness of water film, the velocity of driving and vehicle axle load. There are dynamic water positive pressure zone and negative dynamic water pressure zone at the same time in the tire-water film-road surface interaction region, and under the effect of positive dynamic water pressure and negative dynamic water pressure, the dynamic water to form a strong scour circulation function in the pavement material. At the same time, with the increase of the thickness of the water film layer of the road surface, the speed at which the vehicle can take the risk of water-skiing is decreasing. At the same speed, the sedan is more prone to water-skidding risks than trucks.

Key words: road engineering, dynamic water pressure, fluid-structure interaction, finite element, AH-E type sensor