Published: 7 December 2015
Research & reports
Road controlling authorities,
Road traffic engineers & consultants,
The application of geosynthetics (ie geogrids) for the stabilisation of basecourses prepared with a River Run rounded gravel aggregate was investigated. Reductions in the rate of rut formation by over 50% were observed when geogrids were included either at the basecourse/sub-base interface or at half-height of the basecourse. The rate of rut formation was reduced further if a square type geogrid was used in place of a triaxial type geogrid. It was found that the basecourse rutted rapidly if the surface was not confined, due to the lack of particle interlock and surface confining stress. If the surface was confined with a thin (ie < 40mm) asphalt layer to bind together the particles in the surface, then the aggregate provided significant support and reduced rutting by over 90%, even without the addition of geosynthetic stabilisation.