Analysis And Measurement Of Aerodynamic Field In Vehicle-road System Based On Water Damage Of Road

Compared with the development of the automobile industry, highway network is also expanded rapidly. Road provide service conditions for automobile, and also influence the comfort, safety and operating costs. But now the asphalt pavement has serious early damage, extremely water damage, which reduce the service life of road and ride-ability of car. So a few studies are carried out. However almost all studies are limited, such as the road engineering aim at road structure and material, while the vehicle engineering aim at vehicle performance. And two disciplines aren’t combined closely. The paper considers that the combined action of vehicle-road system, and theoretical analysis, field test, laboratory experiment are used to research the water damage, which support the dispose of the problem.Accurate evaluation of the water damage is the basement of settlement. The essence of genesis and development for water damage is researched through the theoretical analysis and laboratory test. Based on the traditional evaluation method, new test equipment and evaluation method are proposed, which can simulate combine action of vehicle, water, air and road. And also the new method is more suitable for actual.The vehicle-road system is complex, which contains vehicle, water, road and air. The aerodynamic caused by the motion of vehicle and hydrodynamic pressure produced by the water film on the pavement in the extrusion of vehicle, aggravate water damage of asphalt pavement. The theory of aerodynamic and hydrodynamic pressure is studied, and also measuring equipment is developed to measure the force. At last, the change rule of the force under different speed is summarized, which has a good support to analyze the reason of water damage.Ground pressure is the base of different factors in vehicle-road system. When the vehicle is in high speed, the distribution of ground pressure is close to rectangle, and the value of the force is also different. A measuring equipment is invented to research ground force. Firstly, the fundamental and workflow are explained, then the ground force in different motorcycle type and different speed are surveyed. Finally, typical wave shape of dynamic loading for diaxon and triaxial are established, which provide more reliable parameters for performance testing of asphalt mixture.Water is the direct influence factor of water damage. In the vehicle-road system, aerodynamic and hydrodynamic pressure both has an important effect on the permeability of asphalt mixture. Through analyzing the general permeability of asphalt pavement, the space hierarchy model is proposed. And then the model is verified by means of comparison of the permeability under ordinary pressure, positive pressure, negative pressure and alternative pressure. At last, experiment shows that the hydrodynamic pressure would increase the permeability of mixture, which makes the water damage occurs more easily.A test platform is created, which could simulate the influence of hydrodynamic pressure, aerodynamic and vehicle load on the pavement structure. The water stability of semi-rigid base and LSPM flexible base is tested. The process and prevention measure of water damage are checked in the experiment. And also the reliability of the platform is proved by the accelerated pavement test.