I5/SR14 High Occupancy Vehicle LanesLos Angeles, California
California Department of Transportation
As part of a Statewide geotechnical contract with Caltrans, Geocon performed a comprehensive geotechnical investigation using soil boring and rock coring at the Interstate 5/State Route 14 interchange in Sylmar, the northernmost corner of Los Angeles. The proposed improvements consist of constructing a new direct connect bridge and numerous retaining walls to provide several HOV lanes that will allow motorists driving in the HOV lanes to make a freeway-to-freeway transfer without leaving the carpool lanes. The site was known to be contaminated with crude oil and hydrogen sulfide. In addition to contamination issues, the field investigation involved difficult access conditions, restricted work hours, frequent rainy days, and high traffic volume. Geocon was able to mobilize multiple drill rigs with skilled drillers and experienced geologists familiar with Caltrans' drilling criteria. Geocon also provided pressuremeter testing following the drilling operations to provide Caltrans with deformation moduli of soil and rock for use in the final design of foundations. Geocon successfully completed the investigation, meeting the project milestone set by Caltrans.