Geotechnical Characteristics of the Sea Bed Related to Seismo-Acoustics

  • Denzil Taylor Smith
Part of the NATO Conference Series book series (NATOCS, volume 16)

Abstract

The pattern of seismo-acoustic phenomena in marine sediments is often paralleled by such sediments’ geotechnical behavior. Thus a compressional wave velocity variation with depth is closely akin to the void ratio change with pressure seen in the consolidation test, and can be utilised to calculate the unidirectional compressibility of the sediment. Further, by use of a Biot model, permeability can be determined from the velocity-porosity data which allow the rate of settlement of any engineering structure on the sea floor to be derived. The Biot calculation requires an assessment of both frame and shear modulus, achieved by the in situ measurement of the shear wave velocity. This quantity is a definitive geotechnical parameter; it particularly allows the degree of anisotropy of a soil fabric to be postulated of benefit to acoustics and geotechnics alike. The full interdependence of the two can be obtained by the strain rate and strain level correction curves produced by the resonant column apparatus.

Keywords

Clay Permeability Porosity Anisotropy Compressibility 

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Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • Denzil Taylor Smith
    • 1
  1. 1.School of Ocean SciencesUniversity College of North WalesBangorUK

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