LABORATORY INVESTIGATIONS OF THE EFFECTS OF SAMPLING

THE EFFECTS ARE DISCUSSED OF DISTURBANCE ON THE STRENGTH AND SEVERAL ASPECTS OF THE DEFORMATION PROPERTIES OF SATURATED CLAY SOILS. PARTICULAR ATTENTION IS PAID TO THE EFFECTS OF THE INEVITABLE DIFFERENCES BETWEEN THE STRESS HISTORY OF SPECIMENS TESTED IN THE LABORATORY AND THE CORRESPONDING FIELD ELEMENT. SUCH STUDIES OF THE EFFECTS OF DISTURBANCE ARE GREATLY FACILITATED BY THE TECHNIQUE OF PRODUCING A SIMULATED FIELD-ELEMENT IN THE LABORATORY. A SUMMARY IS GIVEN OF INVESTIGATIONS BY OTHER WORKERS AND THE RESULTS OF A PRELIMINARY SERIES OF TESTS ON KAOLIN ARE REPORTED. THESE TESTS ON KAOLIN CONSISTED OF UNDRAINED STRENGTH TESTS, TRIAXIAL DEFORMATION TESTS AND ODOMETER TESTS ON FIELD ELEMENTS, PERFECT SPECIMENS, UNDISTURBED, PARTLY DISTURBED, AND FULLY REMOLDED SPECIMENS. THE MAIN IMPLICATIONS ARE: (1) THE EFFECT OF DISTURBANCE DUE TO THE STRESS CHANGES WHICH MUST ARISE EVEN IN PERFECT SAMPLING IS OF THE SAME ORDER AS THE ADDITIONAL EFFECT OF MECHANICAL DISTURBANCE IN REAL SAMPLING, (2) THE EFFECTS OF DISTURBANCE ON DEFORMATION PROPERTIES ARE GENERALLY GREATER THAN ON STRENGTH PROPERTIES. THE UNDRAINED MODULUS E IS PARTICULARLY SENSITIVE TO DISTURBANCE, (3) A PROMISING METHOD OF ESTIMATING THE TRUE FIELD PROPERTIES OF A SOIL APPEARS TO BE EXTRAPOLATION FROM THE RESULTS OF UNDISTURBED, PARTLY- DISTURBED AND FULLY-REMOLDED SPECIMENS ON THE BASIS OF THEIR DEGREES OF DISTURBANCE, AND (4) AS A GENERAL RULE, IT APPEARS THAT THE TRUE FIELD PROPERTIES WILL BE MOST CLOSELY APPROACHED BY SPECIMENS WHICH HAVE BEEN RECONSOLIDATED TO THE FIELD CONDITIONS PRIOR TO TESTING. /AUTHOR/

  • Supplemental Notes:
    • Vol Ce9, No 1, PP 86-94, 10 FIG, 3 TAB, 13 REF
  • Authors:
    • Davis, E H
    • POULOS, H G
  • Publication Date: 0

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  • Accession Number: 00229039
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 15 2004 2:38AM