A variety of methods have been used during the last 20 years to reinforce soils. One of these methods is soil nailing. Most often, soil nails are installed by inserting steel rods in drilled holes then grouting in-palce. Sometimes the nails are inserted using percussion methods. These methods generally require excavation of a working bench in order for the construction equipment to work below the slope being nailed. These methods are not applicable to repair of small slips or road fills and embankments where access is limited. In July and August of 1992, the USDA Forest Service sponsored a launched soil nailing demonstration project in the western United States. The five week demonstration involved installation of launced soil five week demonstration involved installation of launced soil nails at eight sites in four States and three Forest Service regions. The demonstration included soil nailing of road shoulders, a retaining wall, a cut bank, and a sand bank. Financial and technical assistance was provided by the Federal Highway Administration Coordinated Technology Implementation Program, the States of Washington and Colorado, and the seven National Forests that participated in the demonstrations. The project successfully demonstrated the feasibility of using launched soil nails for the stabilization of failing road slopes. (A)
Samenvatting