In-Situ Undrained Shear Strengths and Permeabilities Derived from Piezometer Measurements
Abstract
Existing theories and models describing stress changes and consolidation-time effects around a pile were used to derive in-situ permeabilities and undrained shear strengths from piezometer probe measurements in smectite- and illite-rich soils. Permeabilities derived from piezometer measurements are in reasonable agreement with laboratory measurements, and calculated undrained shear strengths agree well with strength measurements using standard field and laboratory techniques. Multisensor piezometer probes (2), 10. 2 cm in diameter, were deployed in shallow-water fine grained smectite-rich soils of the Mississippi delta. Pore-water pressures were measured at subbottom depths of 6.5, 12.6, and 15.6 m. Insertion pressures, time-dependent pore pressure decay, and ambient excess pore pressures were determined. Single sensor piezometers (2), 0.8 cm in diameter, were developed for deep-ocean investigations. Before high pressure testing (55 MPa), probes were inserted in reconstituted illitic marine soil to depths of 16.9 and 26.4 cm below the soil- water interface. Insertion pressures and their decay characteristics were monitored.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1986
- Accession Number
- ADA191486
Entities
People
- Huon Li
- Joel Lipkin
- Melvin I. Esrig
- Philip J. Valent
- Richard H. Bennett
Organizations
- United States Naval Research Laboratory