2025 Volume 87 Issue 1 Pages 3-22
Vehicle starting experiment on compacted-snow road surfaces were conducted for mid-sized trucks to determine how stranding occurrence differed by tire type and how effective tire chains were at preventing stranding, using the minimum stranding pit depth (dsp). Experimental results were shown separately according to the type of the compacted-snow: fine-grained compacted snow (small rounded particles) and coarse-grained granular snow (clustered rounded grains or rounded polycrystals). Furthermore, by examining the multiple interacting forces for the marginal state between when the driving wheel slides down versus when it does not slide down the snow slope, the difference in stranding occurrence by tire type and the effectiveness of chain installation were explored in depth from a physical perspective. On the fine-grained compacted snow, the dsp for studless and all-season tires were found to be similar, and the dsp were found to be lower for normal tires than for tires of other types. Regarding chain installation, single- and double-ladder chains were found to be highly effective against stranding; hexagonal chains and fabric chains were also observed to be effective. Vehicles without tire chains were less likely to become stranded on the coarse-grained granular snow than on the fine-grained compacted snow; however, tire chain installation was less effective on the coarse-grained granular snow than on the fine-grained compacted snow. This study enabled the estimation of the frictional force or the scratch resistance force between the tire or chain and the snow slope, suggesting that it may be possible to estimate dsp under other conditions.
