SYMPOSIA PAPER Published: 01 January 1988
STP10337S

Comparison of In-Situ Vane, Cone Penetrometer, and Laboratory Test Results for Gulf of Mexico Deepwater Clays

Source

Site investigations were recently performed offshore at three prospective plat-form sites in water depths between 400 and 500 m in the Gulf of Mexico. Soil conditions at the sites generally range from very soft clays near the seafloor to very stiff clays at 120- to 150-m penetration. Analyses of stress history indicate the soils at these locations are generally normally consolidated. Laboratory tests were performed on recovered specimens to deter-mine the undrained shear strength. Standard laboratory miniature vane shear tests and unconsolidated-undrained triaxial tests were performed in addition to consolidated-undrained tests using stress history and normalized soil engineering properties (SHANSEP) procedures. Tests performed in the field included in-situ vane and cone penetrometer. Cone factors Nk were computed using in-situ vane shear strengths as the reference strength.

This paper compares the results of consolidated-undrained (SHANSEP) laboratory and in-situ tests to determine a relationship that may be used to correlate these results. The effects of soil strength and plasticity are examined and used to correlate shear strength with the liquidity index. A comparison is also made between peak and residual in-situ vane strengths.

This paper further describes how a combination of these in-situ and laboratory tests can be used to characterize a deepwater site for foundation design. Recommendations for future site investigations are also discussed.

Author Information

Johnson, GW
Browning-Ferris Industries, Houston, TX
Hamilton, TK
McClelland Engineers, Inc., Houston, TX
Ebelhar, RJ
S&ME, Inc., Fairfield, OH
Mueller, JL
Conoco, Inc., Houston, TX
Pelletier, JH
Shell Oil Company, Houston, TX
Price: $25.00
Contact Sales
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Developed by Committee: D18
Pages: 293–305
DOI: 10.1520/STP10337S
ISBN-EB: 978-0-8031-5030-0
ISBN-13: 978-0-8031-1188-2