COMMENTS ON THE COMPRESSIBILITY OF PEAT IN NORMANDY

REFLEXIONS SUR LA COMPRESSIBILITE DES TOURBES EN NORMANDIE

VALLEYS AND ESTUARIES IN NORMANDY ARE OFTEN FILLED WITH PEAT WHICH WAS FORMED 7000 YEARS AGO. THE AREA COVERED WITH PEAT IS 170 SQ M, ONE OF THE LARGEST AREAS IN FRANCE. IT IS OFTEN NECESSARY TO BUILD ON THIS HIGHLY COMPRESSIBLE MATERIAL. DETAILS ARE GIVEN OF THE PHYSICAL AND MECHANICAL PROPERTIES OF THE PEAT FOUND IN NORMANDY. IT IS SHOWN THAT IN SPITE OF THE SCATTERING OF VALUES, CORRELATION EXISTS BETWEEN COMPRESSIBILITY AND SOME PHYSICAL CHARACTERISTICS SUCH AS THE MOISTURE CONTENT. THE AUTHOR EXAMINES THE PROBLEM OF OVERCONSOLIDATION OF PEAT WHICH MUST BE TAKEN INTO ACCOUNT IN THE CALCULATION OF SHORT-TERM SETTLEMENT. SEVERAL EXPLANATIONS ARE GIVEN BUT NONE APPEARS TO BE SATISFACTORY. IN PARTICULAR, BRACKISH WATER WHICH FILLED SOME PEAT BOGS A LONG TIME AGO, SEEMS TO BE A SIGNIFICANT FACTOR. THESE OBSERVATIONS LED TO THE DEVELOPMENT OF A METHOD OF STUDYING COMPRESSIBILITY BASED ON THE CALIBRATION OF A SITE BY MEANS OF OEDOMETER TESTS CARRIED OUT IN THE LABORATORY ON UNDISTURBED SAMPLES. THE RESULTS OF THE TESTS ARE APPLIED TO THE WHOLE OF THE AREA STUDIED AND NUMEROUS MOISTURE CONTENT MEASUREMENTS HAVE TO BE TAKEN.

Language

  • French

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Filing Info

  • Accession Number: 01296786
  • Record Type: Publication
  • Source Agency: Institut Francais des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)
  • Files: ITRD
  • Created Date: Nov 21 2010 6:05AM