DBM Completes Foundation Shoring for New UC Santa Cruz Engineering Building
Job Location: UC Santa Cruz Engineering Building, Santa Cruz, CA
Project Owner: University of California, Santa Cruz
Project Description: DBM Contactors Inc. recently completed a $562,000 design-build shoring project for the University of California, Santa Cruz’s new engineering building.
DBM was contracted by the university to design and install approximately 17,000 square feet of temporary soil nail shoring. The three-month project was completed in early January 2003, and construction of the new engineering building is scheduled to conclude in the spring of 2004.
The temporary excavation support system consisted of 648 soil nails, averaging 19 feet in length with a four-inch shotcrete facing mildly reinforced. Even though the building foundation did not exceed 20 feet below grade, soil nail walls ranging from 10 to 20 feet were required to accommodate the placement of a four-foot thick chemically treated and compacted soil mat.
The design of the soil nail walls accommodated the site’s stiff, sandy clay soils. However, site excavation also revealed a cavity system including zones of very loose or very soft soils, loose marble rubble and very weathered marble bedrock with open voids or cavities loosely filled with residual soil. Adjustments to the “standard” soil nail installation approach were incorporated to minimize the possibility of soil sloughing.
Other team members who worked on this project were: DPR Construction – General Contractor, Ground Support, PLLC – DBM Design Engineer, Pacific Crest Engineering, Inc. – Project Geotechnical Engineer.
