Garden Bar Road Bridge 1 Replacement – Nevada County, CA

Holdrege & Kull provided design services for this bridge replacement project over Little Wolf Creek. The existing bridge consisted of a railcar frame with wood decking, founded on concrete spread footings. H&K performed an initial geotechnical subsurface investigation in accordance with the guidelines and reporting requirements of Caltrans’ Foundation Report Preparation for Bridges. Approximately 10 feet of rock core was sampled from each of the proposed abutment locations. Based on the results, H&K prepared design recommendations for earthwork and structural improvements that included design 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 on this federally funded HBP project included resistant boulders and bedrock at both abutments. The new bridge abutments will consist of spread footings founded on competent, weathered rock.