RECORDING DEVICE ADAPTABLE TO THE TEST FOR THE CLASSIFICATION OF SOILS ACCORDING TO THEIR DEGREE OF FROST SUSCEPTIBILITY

DISPOSITIF D'ENREGISTREMENT ADAPTABLE A L'ESSAI DE CLASSEMENT DES SOLS SELON LEUR DEGRE DE GELIVITE

Soils are classified according to their degree of frost susceptibility by comparing the different gradients of the straight parts of the curves representing the swelling of A soil sample as a function of the square root of the frost index, the latter being the integral of the temperature of the cold side of the sample in relation to time. This device described enables the curves representing the swelling of 6 samples to be recorded during the freezing test. The calculation of the frost index and the square root is done numerically. To each soil sample tested is associated an accumulator, which adds up the temperatures, but the square root extractor is common to all accumulators. The result of each measurement is marked on a recorder xy which, at its input end x receives a voltage proportional to the square root of the frost index and at its input end y a voltage proportional to the swelling of the sample. The six curves are traced on the same chart. The beginning of a cycle of six consecutive measurements is triggered off by a clockwork impulse and the duration between the cycles can be regulated at will. The frost test results obtained on the device showed good agreement with the results obtained with the conventional method of manual counting. /TRRL/

  • Corporate Authors:

    Central and Regional Labs of Bridges & Highways,Fr

    58 Boulevard Lefebvre
    75732 Paris Cedex 15,   France 
  • Authors:
    • LAPORTE, J C
  • Publication Date: 1974-2

Language

  • French

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: 88 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00129650
  • Record Type: Publication
  • Source Agency: Central and Regional Labs of Bridges & Highways,Fr
  • Report/Paper Numbers: No. 32 R&D Rept.
  • Files: ITRD, TRIS
  • Created Date: Apr 7 1976 12:00AM