The Deep Patch Slope Repair Method for Roads on Steep Hillsides

摘要

The deep patch method is a technique to repair roads on steep hillsides that have experienced excessive settlement, creep and instability in the fill soil used to create the roadway bench. The method involves excavating a limited depth of the roadway bench in the area of the distress and backfilling with well compacted granular fill with layers of geosynthetic reinforcement. The method has been in use for over 20 years in the Western United States, however little information exists on well documented design techniques. This paper describes the results of a study involving the analysis of the deep patch method by use of a finite difference numerical model. The model is used to illustrate the importance of the thickness of the reinforced mass, the number of reinforcement layers and the spacing of these layers. A large number of models were analyzed to generate design recommendations for the best reinforcement configuration and for minimal geosynthetic tensile strength required.