Effect of Water Surface Tension on Tangential Soil Adhesion（Extracts）

Soil adhesion，especially the tangential adhesion between soil and tire or track，has a significant role on improving the performance of off-road vehicle.On the other hand，soil sticking to tire or track reduces the performance of tire or track of off-road vehicles.In order to solve this problem effectively，the mechanism of soil adhesion should be understood.The purpose of this study was to find out the effect of water surface tension on the tangential soil adhesion force generated between soil particle and the contact surface of material.Glass beads in different diameter were used as models to simulate soil particles and three kinds of materials were provided.The tangential force generated between the glass bead and the plate was measured at various diameters of water film rings formed around the glass beads.Experimental results showed that no matter what kinds of material plates were used tangential adhesion was directly proportional to the diameters of the water film rings even if the diameter of glass beads were different.No matter what kinds of material plates were used，proportional coefficient k which reflects the relationship between tangential adhesion force and water film diameter in the tangential adhesion formula increased linearly with the increase of glass bead diameter.And coefficients of approximate lines were exactly the same if materials with the same hydrophilic were used.Therefore tangential adhesion was closely related to water film rings formed around glass beads.