REDUCED SOIL STRENGTH AND STIFFNESS AT THE TOP OF TUBE SAMPLES

AN INVESTIGATION IS DESCRIBED DESIGNED TO ASSESS WHICH PART OF A TUBE SAMPLE GIVES THE MORE RELIABLE ESTIMATE OF THE ORIGINAL SOIL PROPERTIES IN THE GROUND. A DECOMPOSED GRANITE AND A DECOMPOSED MUDSTONE WERE SAMPLED WITH A 3 IN, AUGER CORE SOIL SAMPLER. IN ONE SET OF TESTS AT EACH SITE, EACH SAMPLE WAS LONG ENOUGH TO PERMIT AN UPPER AND LOWER TEST SPECIMEN TO BE CUT, WHILE IN THE OTHER SET THE ADVANCE OF THE SAMPLER WAS SHORTER, PERMITTING ONLY ONE TEST SPECIMEN PER TUBE SAMPLE. SUBSEQUENTLY AN IMMEDIATE UNDRAINED TRIAXIAL COMPRESSION TEST WAS MADE ON THE SPECIMENS IN THE LABORATORY. SECANT MODULUS VALUES FOR THE SINGLE SPECIMENS WERE FOUND TO MATCH CLOSELY THOSE FOR THE LOWER SPECIMENS, EVEN THOUGH THE SAMPLING FORCES REQUIRED TO OBTAIN THE LATTER WERE MUCH HIGHER. THE INFLUENCE OF THESE FORCES, AND OF SOIL DISTURBANCE ARISING FROM THE SAMPLING PROCEDURES, ON VARIATIONS IN IN TUBE SAMPLE PROPERTIES IS DISCUSSED. IT IS CONCLUDED THAT THE LOWER PART OF A SAMPLE SHOULD GIVE A MORE RELIABLE INDICATION OF ACTUAL SOIL GROUND CONDITIONS THAN THE UPPER PART. /AUTHOR/

  • Corporate Authors:

    Proc Aust-n.Z. Conf Geomech /Australia

    ,    
  • Authors:
    • Lang, J G
  • Publication Date: 0

Media Info

  • Features: Figures; References; Tables;
  • Serial:
    • Volume: 1

Subject/Index Terms

Filing Info

  • Accession Number: 00230449
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: pp 232-7 Conf Paper
  • Files: TRIS
  • Created Date: Nov 14 1973 12:00AM