Three Road-Crushing Demonstration Projects

Abstract

At the Sixth International Conference on Low-Volume Roads Yves Provencher, Forest Engineering Research Institute of Canada, presented a paper on the F.A.H.R. rock crusher mounted to a front-end loader. At the same time the Coronado National Forest in Arizona was renting a F.A.H.R. rock crusher for an in-place road-crushing project. In 1997 San Dimas Technology and Development Center, in partnership with the Coronado National Forest, sponsored two demonstration projects to further test the crusher at unique locations to gain additional information from actual field trials. These projects were located on the Rio Grande National Forest in Colorado and the Plumas National Forest in California. The three projects are described here, with results and conclusions gained from the demonstration projects. The concentration is on the characteristics of the processed material. Samples taken from windrows during the crushing operation were tested to determine hardness and gradations before and after crushing. Cost varied from $8 to $26 per m3 including roadbed preparation, crushing, and blading. Rocks and boulders to 405-mm maximum size were crushed. The processed material has a maximum size of 50 to 75 mm. The product produced by the crusher offers a viable alternative for aggregate on a road surface, particularly as a road surface cushion material, where the quality and expense of standard crushed aggregate, such as base course material, are not needed on low-volume roads.