Analysis And Research On Tire Road Contact And Anti Slip Characteristics Based On Real Road Surface Texture And Dry Wet State

With the continuous increase in car ownership,the problem of driving safety is becoming increasingly prominent.Under rainy conditions,water film will be formed on the road surface,which makes the vehicle tires skid and is very likely to cause traffic accidents.Therefore,it is particularly important to investigate the tire/road coupling and the performance of vehicle braking from the perspective of tire-road contact.This paper mainly uses ABAQUS and other software to analyze the influence of road surface on vehicle and tire braking performance based on factors such as adhesion coefficient and braking distance on dry/waterlogged road surface.Based on the geometric and material properties of tires,this paper completes the three-dimensional modeling of tires,uses a three-dimensional scanner to obtain the road surface texture information,and then reconstructs the road surface model.The tire is contacted with the road surface model in ABAQUS software,and the tire/road surface finite element model is established by setting the contact conditions.The contact stresses between the real tire and the road surface are obtained by using pressure-sensitive adhesive sheet test and compared with the simulation results to verify the reliability of the model,and the finite element tire/road surface model under dynamic condition is verified by replica paper test.Based on the "implicit then explicit" method,the tire operating conditions under dry/water pavement conditions were analyzed.Using the implicit analysis method(ABAQUS/STANDARD),the effects of tire load and tire inflation pressure on the maximum contact stress and maximum shear stress of tire-pavement contact on different pavement surfaces were analyzed,and it was found that the greater the roughness of the pavement,the greater the maximum contact stress and maximum shear stress.The effects of tire speed,inflation pressure and pavement type on the pavement adhesion coefficient were analyzed,and the results showed that the higher the tire speed and inflation pressure,the lower the pavement adhesion coefficient,while the greater the roughness of the pavement,the greater the pavement adhesion coefficient.Using the CEL method in the explicit analysis method(ABAQUS/EXPLICIT),a tire-water film-pavement(flow/solid coupling)model is established,in which Eulerian units are used to describe the water movement,and the validity of the tire water-sliding model is verified by the NASA watersliding empirical formula.Based on the established water-sliding model,the relationships between water film thickness,tire inflation pressure,pavement type and waterlogged pavement adhesion coefficient are obtained.The CARSIM software is used to parametrically model the vehicle as a whole and determine the parameters of the seven internal subsystems of the vehicle and the road surface.The SIMULINK module is simulated jointly with CARSIM software,and the program is written in the SIMULINK module to put the vehicle in ABS state(slip rate of20%)when braking.The combined vehicle-road model was used to analyze the effects of water film thickness,vehicle speed,and pavement type on braking distance,and the relationship between safety sight distance and vehicle speed,pavement type,and water film thickness was analyzed based on driver reaction time.The calculated results are compared with the data in the specification,and the skid resistance of the three dry/water pavement types are comprehensively analyzed,and the results show that PAC pavement has the best skid resistance,followed by SMA pavement and AC pavement in order.In this paper,finite element tire/pavement,tire-water film-pavement,and vehicleroad combination models are established based on real pavement textures.The reliability of the contact model is verified through tests to analyze the skid resistance of tires on different pavement types.Based on the analysis results of the finite element tire/pavement and tire-water film-pavement models,a vehicle-road coupled model is established to compare the two conditions of normal dryness and the most unfavorable water accumulation to provide reference for pavement design in rainy areas.