Expendable Doppler Penetrometer: A Performance Evaluation
Final rept. Jan 1973-Oct 1976
CIVIL ENGINEERING LAB (NAVY) PORT HUENEME CA
Pagination or Media Count:
An expendable penetrometer using the Doppler principle has been developed expediently test seafloor soils to a depth of 9m 30 ft at water depths to 6,000m 20,000 ft. The velocity of the penetrometer is measured as it penetrates seafloor soils. From the velocity record, soil penetrability and an estimate of the undrained shear strength profile can be calculated. The penetrometer has a mass of 173 kg 12 slugs, is 2.9m 9.5 ft long, is 90mm 3. 5 in. in diameter, and is easily deployed from a ship. This report presents data from 11 tests at four locations off the southern California coast. Undrained shear strength profiles determined from penetrometer data are compared to other types of in-situ data and core data. It is concluded that the expendable Doppler penetrometer is reliable and simple to use and that reasonable estimates or - 30 of actual values of undrained shear strength profiles can be obtained even though the analyzed phenomenon is complex. This tool will be of particular value in surveying potential embedment anchor or foundation locations and can, for some cases, provide information sufficient for design purposes.
- Physical and Dynamic Oceanography
- Test Facilities, Equipment and Methods