I-15 Reconstruction

Salt Lake City, Utah

Terracon provided geotechnical engineering and consulting services on the southern half of the $1.6 billion I-15 reconstruction, the nation’s largest design/build transportation project. Services included geotechnical design, embankment construction, reinforced earth retaining walls and deep foundation design for bridge structures. Instead of completion in a standard eight-year time frame, the project was completed successfully in half the time. Terracon developed and implemented a project management system that provided a geotechnical report for each structure. The attention to detail mandated by this system resulted in Terracon delivering 100 percent of the reports on schedule. Geotechnical engineering studies were performed on the pile foundations and approach embankments for 135 bridges for primary and secondary settlement and slope stability. All designs were required to meet very tight primary settlement restrictions prior to construction. The required installation of approximately 27 million feet of wick drain in the varied soils allowed for more rapid consolidation to meet the accelerated schedule.