Abstract:
Extreme rainfall associated with Hurricane Helene triggered numerous shallow slope failures across the southeastern United States. One such failure occurred along a roadway embankment in Greer, South Carolina, where approximately 6 m (20 ft) of slope height experienced shallow sloughing following prolonged rainfall. Although the failure had not yet impacted the roadway, continued erosion posed a long-term risk to roadway stability, nearby utilities, and access to adjacent properties. A geotechnical investigation consisting of soil borings, sampling, and laboratory testing was performed to characterize subsurface conditions and evaluate the failure conditions. Several stabilization alternatives were considered, including mechanically stabilized earth walls, soil nail walls, and reinforced slope systems incorporating turf reinforcement mats (TRMs). Due to site constraints, including the roadway at the crest, utilities within the embankment, and a stream corridor at the toe, structural wall systems were considered more invasive and difficult to construct. A TRM system combined with driven anchors was ultimately selected to provide near-surface reinforcement and erosion resistance. This paper presents the investigation findings, evaluation of stabilization alternatives, and design considerations associated with the selected repair approach.