Non-Linearity and Small Strain Behaviour In Lacustrine Clay

This book describes how the pre-failure stress-strain behavior of post-glacial lacustrine soils was investigated through an extensive triaxial testing program that was conducted on natural block samples of Kloten clay. A detailed study of the role of stress path history and anisotropy on the non-linear elasto-plastic stiffness behavior was performed. Distinct horizontal stratification of clay and silt layers, due to the annual fluctuation in the deposition mode in lakes, is typical for lacustrine deposits. This inherent anisotropy of the subsoil influences its mechanical behavior significantly. Consequently, natural block samples were taken using a newly developed tube with a design based on extensive literature studies and testing programs. Pre-failure stress-strain behavior was investigated in the triaxial apparatus with a novel measurement system, specifically designed to perform direct measurements of axial and radial displacements. Two miniature submersible linear variable differential transducers (LVDT’s) are fixed directly onto the soil specimen with a pair of mountings for the axial displacement measurement. This device is capable of recording displacements accurate to within 5 microns, corresponding to 0.01 % axial strain, over a range of 14 %. The radial displacement measurement is accomplished by a newly designed laser scanning device consisting of three lasers mounted inside the triaxial cell around the test specimen. This device is moved in the axial direction over the entire specimen height and provides the absolute and relative radial sample dimension during the test performance, determined without contact, with an accuracy of 10 microns, which corresponds to 0.04 % radial strains over a range of 20 %. A circular slice approach is proposed for the calculation of the specimen volume from the laser scan data.

  • Availability:
  • Corporate Authors:

    Swiss Federal Institute of Technology Zurich

    Zurich,   Switzerland 
  • Authors:
    • Messerklinger, S
  • Publication Date: 2006

Language

  • English

Media Info

  • Media Type: Print
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 477p

Subject/Index Terms

Filing Info

  • Accession Number: 01140635
  • Record Type: Publication
  • ISBN: 9783728130839
  • Report/Paper Numbers: IGT 225
  • Files: TRIS
  • Created Date: Sep 24 2009 4:51PM