Characterization Of Road Topography And Effects Of Solid Particles On Wet Adhesion Properties Of Tread

When a car running on the rough road, the friction between the tire and theroad transfers a variety of interaction forces between the vehicle and the road. Oncethe road surface is covered by water film which generates dynamical lubrication onthe car running at a high speed, the wet adhesion properties of tire will decrease,and finally hydroplaning phenomenon will happen, which greatly reduce thestability and safety of the car. Therefore, the research about the skid resistance oftire/road is of great practical signification.The characterization of road surface topography and the effects of solidparticles on wet adhesion properties of tread were studied in this paper. In the studyof three-dimensional characterization of road surface topography, thecharacterization parameters of surface topography which include ISO25178parameters and connectivity parameters were used to characterize thethree-dimensional topography of road. By controlling the road surface roughnessequally a series of simulated road surfaces which include horizontal slot, doubleslot, chute, double chute and isotropic slot were constructed to analyze the effectsof groove type and sampling interval on the characterization parameters of roadsurface quantitatively. The performance of the sliding and wear of the road wasalso analyzed in depth. The results show that the sampling interval has little impacton the characterization parameters, and the performance of the non-slip, abrasionand connectivity of the road was improved by the help of road grooves. The skidresistance of the double slot and double chute is better, the pavement of double slothas the better performance of load and wear, the connectivity of the chute road isthe best between the grooves. These results will provide some theoretical referenceto the design of road grooves and the research of the tire/road skid resistance.In the study of the effects of solid particles on wet adhesion properties of tread,the effects of volume concentration of solid particles in rainwater were fullyconsidered, a hydroplaning model based on average flow equation was developed tosimulate viscous hydroplaning of tire/tread, and the affects of hydrodynamic actionand squeeze action were also taken into account. This model could be used toanalyze the effects of solid particles, external loads, initial height and sliding speed on wet adhesion performance of tire with numerical iterative solutions of FiniteDifference Method. Meanwhile, vertical deformation and pressure distribution ofthe tread unit also were analyzed in depth. The results show that wet adhesionproperties of tire were greatly affected by the factors of external loads, initialheight and sliding speed and so on, and the performance could be improved byreducing the volume concentration of the particles. These results will have greatcontribution to the progress of tire/road viscous hydroplaning theory.