ENGINEERING PROPERTIES OF CLAY SHALES; REPORT 3, PRELIMINARY TRIAXIAL TEST PROGRAM ON TAYLOR SHALE FROM LANEPORT DAM

Three triaxial tests were conducted on clay shale specimens from Laneport Dam. The specimens were 3 in. long by 1.4 in. in diameter. The purpose of the test program was to evaluate the influence of temperature variation on pore pressure in clay shale, and stress-strain and pore pressure behavior due to incremental isotropic and axial and lateral stress changes. The results of this experimental program indicate that for the clay shale studied, the following conclusions can be drawn: (a) temperature rises cause substantial pore pressure increases in clay shale, which increase linearly with effective stress; (b) swelling under isotropic stress decrease in linear on a volume change; (c) the clay shale was found to have anisotropic elastic properties with a lateral stiffness almost twice the vertical stiffness; (d) under isotropic stress changes, values of pore pressure parameter B were found to range from 0.84 to 0.96, but were usually around 0.90; (e) in the one specimen taken to failure, the deviator stress at failure was 438 psi, which gives a shear strength of almost 16 tsf; (f) for axial loads up to 20 percent of the failure value, pore pressures and strains were found to be completely reversible, and this was substantially so even for an applied axial stress of 290 psi, equal to 66 percent of the failure value; (g) failure occured at an axial strain of 1.2 percent; and (h) inspection of the failed test specimen showed a distinct failure plane with an angle to the horizontal varying from 55 to 63 degrees. /Author/

  • Corporate Authors:

    U.S. Army Waterways Experiment Station

    3909 Halls Ferry Road
    Vicksburg, MS  USA  39180-6199
  • Authors:
    • Parry, RHG
  • Publication Date: 1976-9

Media Info

  • Features: Appendices; Figures; References;
  • Pagination: 82 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00145073
  • Record Type: Publication
  • Report/Paper Numbers: Tech. Rpt. S-71-6
  • Files: TRIS, ATRI
  • Created Date: Mar 30 1977 12:00AM