Prediction of aspects of soil-wheel systems.

A simple formula is given which predicts maximum stress-depth relationships under wheels from vertical wheel load and the tyre inflation pressure. Predictions were compared with stress measurements at a depth of 30 cm under a wide range of vehicles. Stress measurements at a depth of 15 cm showed that a very wide diagonal rubber tyre produced higher peak stresses than a very wide radial polyurethane tyre. If values of soil cohesion and angle of internal friction are available, the model SOCOMO can predict size and location of plastic regions in soil under tyres. If not, it is possible to measure useful relationships between soil water content at traffic event and traffic-induced change of any soil physical propert