Field and laboratory strength analysis of a forest road in NW Oregon and its association with the formation of ruts /
Abstract (Summary)A one-mile section of a newly constructed forest road in Northwest Oregon was analyzed for various aspects of subgrade and surface strength and their association with the formation of ruts during the first hauling season. Field and laboratory tests were completed on the road and the road materials to determine general characteristics and potential for improved performance. Field testing included the Sand Cone test on the subgrade layer and the collection of Clegg impact values for the subgrade and surface layers. Laboratory tests included sieve analysis and Atterberg limits as well as California bearing ratio 15-point tests to determine the general soil characteristics and the potential strength of the material. The incidence of ruts was measured after the first hauling season and was used as the environmental performance variable. The results of this case study show that compaction of the subgrade was the most important aspect in providing strength to the road. Other soil properties were not found to influence the strength of the soil when compared to the compaction tests. Study results suggest that the potential strength of the soil was not achieved in the field, likely due to high water contents during construction. Conclusions on the association of the material properties and the formation of ruts cannot be drawn at this time.
School:Oregon State University
School Location:USA - Oregon
Source Type:Master's Thesis
Date of Publication: