Stochastic modelling of road roughness

Klas Bogsjö

Abstract:: Road profiles are studied from a vehicle fatigue perspective. Roads ranging from smooth motorways to very rough gravel roads have been measured. It is observed that the measured roads consist of irregular sections, which makes the stationary Gaussian model unsuitable in this application (Paper A). In Paper B, it is verified that irregular sections cause the major part of the fatigue damage. An algorithm is presented which automatically identifies the irregularities. Based on this result, a new model is proposed, which includes randomly shaped and placed irregularities. Paper C describes a new method for road model evaluation. The method facilitates simple comparison of road model accuracy. Also, the method defines a target which makes it simple to reject or accept models.