NAVAL OCEAN RESEARCH AND DEVELOPMENT ACTIVITY STENNIS SPACE CENTER MS
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.
Published in American Society for Testing and Materials Special Technical Testing Publication 863, p83-100, 1986.