EastYorkTTCFan
Senior Member
It seems very unlikely to me that the compressive force of a train is enough to eliminate all the water from wet leaves and turn them to dust!
It's the wet leaves themselves that causes the slip. (I'd think that the coarseness of the sand would be the factor - I'd think that coarse sand should reducing slippiness).
Engineers work out why fallen leaves on train tracks are so slippery
A team of engineers at the University of Sheffield has found an explanation for the extreme slipperiness of train tracks when leaves have fallen on them. In their paper published in Proceedings of the Royal Society A, the group describes testing the interaction of leaves with iron in their lab...
phys.org