A midstream transmission group asked GeoStabilization International®, a soil nail wall contractor and pipeline geohazard mitigation experts, to look at an urgent slide on an extensive cross-country natural gas transmission line embedded in a steep mountainside. The slope appeared to have been disturbed by landowner excavation activities, causing the large landslide and loss of soil retention. The earth movement caused nearly four feet of horizontal deformation along the line spanning more than 175 linear feet, putting the 24-inch high-pressure line in danger of imminent rupture.
A GeoStabilization representative completed a field survey to acquire site measurements and photographs. This data was used to produce field sketches. These were then developed into an estimate and eventually turned into a global stability model to verify the field observations and initial conceptual design approach. GeoStabilization’s engineers accomplished their site visit, all modeling, and design within three days at no cost.
Our design used soil nailing to construct a soil nail wall for slope stabilization. The initial design called for multiple rows of up to 40-foot-long SuperNails® with a reinforced shotcrete panel above and below the active pipeline. When GeoStabilization’s crews began drilling for the soil anchors, they had to utilize special equipment and procedures to ensure their safety due to the severity of the slope’s grade. Once the soil nailing was complete, a steel-reinforcing element was connected to the soil nails. The shotcrete was then sprayed to the slope’s surface and encapsulated the reinforcing element.
During construction, GeoStabilization’s crews encountered bedrock at shallower than expected depths in some locations, allowing our engineers to re-model and revise the design to include shorter soil nails. The refined design with the shorter SuperNails® saved the client nearly 30% of the original price.
Observing the surrounding environment is crucial when protecting critical oil and gas infrastructure. As described above, our field crews recognize site condition changes which are then transmitted to our engineers, allowing real-time design changes to ensure a satisfactory solution is installed.
Our teams have provided residential slope stabilization, slope monitoring, slope protection, and landslide prevention services for over twenty years. Contact GeoStabilization International® at 855-579-0536 to learn how to utilize our geohazard mitigation services for your geotechnical application.
If you are interested in a no-obligation site visit to determine if our services fit your geohazard mitigation needs, call us at 855-579-0536 or fill out our contact form.
