GeoStabilization International® collaborated with USFS Geotechnical Engineers on a plan to stabilize an infinite slope failure that regularly deposited rockfall debris on Hyalite Canyon Road at the base of a 300-foot, 1H:1V slope. Catastrophic failure of the upper mantle of colluvium could conceivable deposit thousands of cubic yards of material into Hyalite Creek which provides 40% of the drinking water for the city of Bozeman.
The plan was twofold; a soil nail buttress was constructed at the top of the scarp to arrest further movement of the colluvium overburden, and a GCS® rock catchment wall was constructed at the bottom to collect loose debris. Project totals included (303) 40-foot soil nails, (75) micropiles, 3,000 SF of shotcrete, and 3,840 SF of GCS® wall. GSI® crews successfully completed this challenging project during several inclement weather events typical for the climate of Montana.
A prime contractor constructed a MSE bridge abutment with a design height of 20 feet before realizing that the grades leading up to the bridges would require abutments in excess of 30 feet.