Mechanistic Design of Low Volume Road Structures

This paper presents a new design approach for assessing the risk of excessive permanent deformation development in soft subgrade soil underlying a low volume road of thin structural layers exposed to heavy wheel loads i.e. Mode 2 rutting using the terminology defined in the EU-funded ROADEX project. The approach is essentially based on back­ calculating the results of 3D Finite Element modelling produced with the PLAXIS software package in a way that allows obtaining the same result in terms of ultimate load carrying capacity of the subgrade soil by a simple hand-calculation procedure as would be obtained by sophisticated 3D FE modelling of the loading arrangement / road structure / subgrade soil combination in question.