Gold Hill Road Bridge over Auburn Ravine – Placer County, CA

Holdrege & Kull performed a geotechnical subsurface investigation and provided engineering design recommendations for this bridge replacement project. The firm also performed an Aerially Deposited Lead (ADL) and Naturally Occurring Asbestos (NOA) site investigation. The investigation for this federally funded HBP project was performed following the guidelines and reporting requirements of Caltrans’ Foundation Report Preparation for Bridges. Recommendations included provision of parameters for foundation types and embedment depths, allowable soil bearing capacity, foundation soil friction coefficients, retaining wall lateral earth pressure coefficients, and seismic design parameters. Project challenges included resistant boulders on the north abutment and resistant boulders in highly weathered granitic rock on the south abutment. The new bridge abutments will consist of spread footings founded on weathered granitic rock.