Erosion susceptibility of granular pavement materials

Abstract

Turbulent flows, such as wind and runoff water, affect the integrity of base granular materials in paved roads shoulders and unpaved roads. This paper presents the results of a laboratory investigation on the effect of base granular gradations on their erosion resistance under turbulent flows. The tests were performed with the turbulent flow test designed to be used with conventional geotechnical laboratories equipment. Several gradations curves, within and outside the Quebec Ministry of Transportation grading envelope, were tested in order to examine the influence of the variation of base granular materials gradation characteristics on the erosion susceptibility. For unbound materials, it was found that properties related to material voids and the permeability of the material (uniformity coefficient, fine fraction porosity and estimated permeability) and property related to the fine particles content are strongly related to the erosion rates (ER) measured with the turbulent flow test. It was demonstrated that the performance of base granular materials under turbulent flows can be controlled using these specific parameters.