Field and Laboratory Testing Program for the Seismic Evaluation of Timemaha Dam, California

This paper is a case study of a site investigation for the Tinemaha Dam (Dam) to determine material properties required for nonlinear dynamic analysis of the Dam, Due to concerns by the California Department of Water Resources (DWR) and Los Angeles Department of Water & Power (LADWP) regarding the geotechnical stability of the Dam a comprehensive field and laboratory investigation was conducted. As a part of the investigation of the Dam, static and seismic Cone Penetration Tests (CPT), Standard Penetration Tests (SPT), seismic down hole velocity and seismic refraction survey lines were conducted by the LADWP and Dames & Moore consultants (D&M). The liquefaction potential of the Dam was evaluated using empirical methods based on CPT and SPT data. Liquefaction analyses using both methods produced factors of safety against liquefaction. Parameters such as fines content and maximum shear modulus were plotted and correlations were drawn for the site. 12 pp., 7 figures.