Landslide Stabilization Design
This project is a design-build landslide stabilization project in Sheridan, Wyoming. EA is teamed with Hayward Baker and Trihydro Corporation. The project involves slope stabilization for three separate sites within Sheridan. EA performed initial site characterization including geologic mapping, exploratory drilling and sampling, laboratory testing, and slope inclinometer and vibrating wire piezometer installation and monitoring. EA completed slope stability analyses, seepage modeling, hydraulic analyses, and structural calculations to aid in the stabilization design. EA designed the slope stabilization for the three sites and prepared construction drawings, specifications, and design reports for each site. The slope stabilization design includes a soil nail wall, a soldier pile wall with grouted anchors, horizontal drains, a maintenance path including a MSE wall, French drain, gabion basket wall, and toe stabilization design. EA will perform construction oversight services for construction of the slope stabilization for the sites.
The Town of Sheridan has graciously shared the feed from the time lapse camera that they have had in place for this exciting project.
Relic Landslide Retaining Wall Design
Engineering Analytics, Inc. (EA) was retained by Maryland Creek Ranch to provide the design for a site that required the investigation of a relic landslide complex. A number of geologists and engineers reviewed mapped relic landslide features and site reconnaissance. Over 50 geotechnical borings were drilled and 10 test pits were excavated at the site to investigate the landslide features and collect soil samples.
Inclinometers and piezometers were installed more than 10 years prior to development of the site to monitor slope movement and groundwater fluctuation. Inclinometer and piezometer data were used to guide additional geotechnical investigations and the design of stabilization measures. Site constraints and considerations for design were relic landslides, slump features, steep slopes, and shallow groundwater. The design of stabilization features for the infrastructure included the installation of 4,500 feet of horizontal drains, 13,000 feet of underdrains, and 45,000 square feet of soil nail, ground anchor, and Hilfiker wall systems. The piezometers and inclinometers will continue to be monitored after construction.
Retaining Wall Remediation
Engineering Analytics performed a geotechnical investigation and developed remediation plans for several failed retaining walls at a multi-million-dollar estate in Aspen, Colorado. A forensic geotechnical investigation was performed to determine the cause of failure of the walls. EA provided final design recommendations for three walls which were subsequently repaired or replaced. The project was awarded the Best Residential Project for 2012 by the block manufacturer.
Roadway and Landslide Stabilization
Engineering Analytics staff investigated distress to the roadways of a large private housing development in Colorado Springs, Colorado. The development contained 23 active landslides, as well as roadway distress due to settlement of inadequately compacted fill material. EA staff performed a geological, geotechnical, and hydrogeological investigation to analyze the roadway settlement and the landslides. We prepared plans and specifications for repair of nine areas. Additionally, one of the landslides was instrumented to provide real-time monitoring of movement and to allow warning of future landslide movement. EA staff provided geotechnical QA/QC during construction of these projects.
St. Vrain Mill Stabilization
Mora, New Mexico
EA was retained to perform a field investigation, design, and construction oversight for the stabilization of the historic St. Vrain Mill foundation for the St. Vrain Mill Preservation and Historical Foundation in Mora, New Mexico. The mill is a 3-story masonry block structure with walls at a 23-foot height and 30-inch thickness constructed in 1864. Cracks in the east and west foundation walls developed with wall separation of up to 8 inches from collapsing soils. The project included a site visit, evaluation of subsurface and groundwater conditions, and foundation repair recommendations. Based on the structural assessment of the building and the geotechnical assessment of the soils, the building required foundation and wall stabilization. Six options were considered for long-term stabilization and an approach of permeation and compaction grouting was selected. A geotechnical report was compiled and submitted in 2015. In early 2018, EA provided construction oversight of the mill foundation stabilization that included permeation grouting to a depth of 4 feet below the exiting foundation, and compaction grouting to a depth of 24 feet below the existing foundation.