MECHANICAL PROPERTIES OF CLAY UNDER REPETITIOUS LOADS

THE FACTORS WHICH GOVERN THE SHEARING CHARACTERISTICS OF CLAY ARE THE APPLIED STRESS CONDITION, VOID RATIO, STRESS HISTORY, TEMPERATURE, ETC. OF THESE, STRESS HISTORY HAS NOT YET BEEN CLARIFIED IN A CONSISTENT MANNER. TRIAXIAL REPETITIOUS COMPRESSION TESTS WERE PERFORMED ON SATURATED REMOULDED CLAY SPECIMENS IN AN UNDRAINED CONDITION, AND THE CHANGES IN CERTAIN MECHANICAL PROPERTIES OF CLAY DUE TO REPETITIOUS LOADING WERE INVESTIGATED. THE INFLUENCE OF STRESS HISTORY ON THE UNDRAINED SHEAR STRENGTH WAS DISCUSSED. THE PRINCIPAL CONCLUSIONS OBTAINED FROM THESE TESTS ARE: (1) A TANGENTIAL ELASTIC MODULUS AT EACH STRESS LEVEL ABOVE A CERTAIN LEVEL MAY GREATLY INCREASE UP TO THE 2ND OR 3RD CYCLE, AND THEN GRADUALLY DECREASE. IT IS A CONTRARY TENDENCY IN THE CASE OF SAND. (2) FOR SANDS, IT HAS BEEN PROVED THAT THE RESIDUAL STRAIN AT THE NTH CYCLE IS PROPORTIONAL TO REPETITIOUS CYCLE NUMBER. BUT, FOR CLAYS, THIS PROPORTIONALITY MAY NOT NECESSARILY BE VALID. (3) IT MAY BE SUPPOSED THAT IF CLAY SPECIMENS WHOSE WATER CONTENTS ARE EQUAL BUT WHOSE CONSOLIDATION HISTORIES ARE DIFFERENT ARE REMOULDED BY APPLYING REPETITIOUS LOADS, THE RESIDUAL EFFECTIVE STRESSES IN THE SPECIMENS AFTER REMOULDING ARE ALMOST EQUAL. (4) THE FAILURE ENVELOPE LINE IN TERMS OF EFFECTIVE STRESS IS COMMON FOR ALL THE TESTS WHICH INCLUDE THE USUAL COMPRESSION TESTS AND SHEAR STRENGTH AND STRAIN WHICH APPEAR IN THE SPECIMEN AT FAILURE BECOME NEARLY CONSTANT DUE TO REPETITIOUS LOADING IRRESPECTIVE OF ITS HISTORY, WHETHER IT IS NORMALLY CONSOLIDATED OR OVERCONSOLIDATED. /RRL/A/

  • Supplemental Notes:
    • No 12b, pp 139-146
  • Corporate Authors:

    Kyoto University

    Disaster Prevention Research, Gokasho
    Uji City, Kyoto,   Japan 
  • Authors:
    • Murayama, S
    • Kurihara, N
  • Publication Date: 1969-3

Subject/Index Terms

Filing Info

  • Accession Number: 00234921
  • Record Type: Publication
  • Source Agency: Road Research Laboratory /UK
  • Files: TRIS
  • Created Date: Oct 13 1970 12:00AM