THE STRUCTURE OF CLAY AND ITS IMPORTANCE IN FOUNDATION ENGINEERING

THE TERMS STRESS, DEFORMATION AND RUPTURE AS APPLIED TO SOILS ARE DISCUSSED. THE SAME PRINCIPLES WHICH GOVERN THE DESIGN OF SUPERSTRUCTURES APPLY TO THE GROUND ON WHICH SUCH A STRUCTURE IS BUILT. THE STRENGTHS AND STRESS-STRAIN RELATIONSHIP OF CONSTRUCTION MATERIALS, AS WELL AS STRESS DISTRIBUTION IN INDIVIDUAL MEMBERS OF A PARTICULAR STRUCTURE MUST BE KNOWN; IT IS ALSO NECESSARY TO KNOW THE SAME FACTORS FOR THE SOIL UNDERNEATH TO DETERMINE THE SAFETY AGAINST RUPTURE AND SETTLEMENT OF THE STRUCTURE DUE TO COMPRESSION AND DEFORMATION OF THE SOIL. TEST METHODS ARE REVIEWED FOR DETERMINING COMPRESSIBILITY OF CLAY AND ITS MEASUREMENT. THE DIFFERENCE IN COMPRESSIBILITY BETWEEN UNDISTURBED AND REMOLDED CLAYS VARY CONSIDERABLY. CLAY BOND AND ELASTICITY ARE DESCRIBED FROM UNCONFINED AND CONFINED COMPRESSION TESTS. REMOLDING EFFECT IS DISCUSSED OF PILE- DRIVING ON THE STRUCTURE OF CLAY. RESEARCH IS REVIEWED, BUT LEADS TO THE CONCLUSION THAT A DEFINITE BEARING VALUE OF CLAY DOES NOT EXIST. EXCAVATION IS SHOWN TO BE THE ONLY RELIABLE METHOD FOR REDUCING SETTLEMENTS. OBSERVATION OF SETTLEMENT AND BUILDING CONSTRUCTIONS INDICATES THAT THE WHOLE PROBLEM OF BUILDING FOUNDATIONS ON CLAY BOILS DOWN TO 2 SIMPLE PRINCIPLES: (1) DO NOT DISTURB THE NATURAL STRUCTURE OF THE CLAY, AND (2) DECIDE ON A CERTAIN RATE SETTLEMENT WHICH SHOULD NOT BE EXCEEDED AND DETERMINE THAT PRESSURE WHICH WILL CAUSE THIS RATE OF SETTLEMENT. THE DIFFERENCE BETWEEN THE BUILDING LOAD AND THE ABOVE PRESSURE IS THE WEIGHT OF THE SOIL WHICH MUST BE REMOVED BEFORE ERECTING THE BUILDING.

  • Supplemental Notes:
    • Vol 19, No 4, PP 168-209, 30 FIG, 1 PHOT, 25 REF
  • Authors:
    • Casagrande, A
  • Publication Date: 0

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Filing Info

  • Accession Number: 00231372
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 3 1970 12:00AM