North Mountain Geohazards SOQ

Relevant Project Experience | SOQ

Highway 40, Colorado

I-25 La Bajada Hill Settlement and Slope Stability WSP was the geotechnical de signer for the I-25 embankment mitigation project between Albuquerque and Santa Fe. The embankment was widened in the early 1980s with high shale content fill, which has subse quently deteriorated and re sulted in excessive pavement settlement and marginal slope stability. Mitigation efforts in cluded comparative cost analysis of mechanically stabilized earth buttressing, soil nail/ground anchor stabilization, and ground improvement. The ground improvement option was selected since it addressed both settlement and slope sta bility. The ground improvement design consisted of soil mix columns supporting a geog rid load transfer platform that bridges the underlying columns and supports a reconstructed pavement structural section. A performance-based design was presented with flexibility for the column diameter and spacing. The contractor selected 10-foot diameter columns, and over 960 soil mix columns were installed, comprising over 300,000 CY of soil cement. The project was successfully completed in 2024.

State Road 39, Ogden Canyon Phase 1 and 2 Transportation Use Study, Utah Phase 1 of the Ogden Canyon Transportation Use Study includ ed a literature search and a brief field trip to provide a high-lev el evaluation of the type and severity of geological hazards that could affect future trans portation improvements within the canyon, as well as east of the canyon along both sides of Pineview Reservoir. Phase 2 of the study provided a more detailed feasibility level invento ry and prioritization of rockfall hazards.

WSP worked directly with CDOT to identify high priority areas for scaling efforts. The project was a two-mile stretch through Byers Canyon along Highway 40. Over a two-week period, the WSP geohazards team directed two scaling crews on which rocks to knock off the rock face based on fractures, surrounding geologic structures, and rock orientation in the slope. Both scale bars and airbags were used to address a variety of different sized rocks. WSP staff also utilized their rope access training to assess the slope from all angles. This work helped reduce the amount of rock that was falling into the road, causing travel hazards throughout the canyon.

Client: Minnesota Department of Transportation (NMDOT)

Client: Colorado Department of Transportation (CDOT)

Client: Utah Department of Transportation (UDOT)

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