THE DESIGN PARAMETERS OF VERTICAL DRAINS IN THE LIGHT OF THE FIELD TEST RESULTS FROM HELSINKI, FINLAND

The design parameters de (equivalent drain diameter) and cvh (consolidation coefficient) relating to vertical drains are subject to uncertainty, particularly when the drains are prefabricated and band-shaped. In order to elucidate these points, a large-scale field test comprising 10 test areas, 9 of which were vertically drained by displacement type sand drains (150 and 400 mm dia), prefabricated band- shaped drains (geodrain), and 500 mm dia. lime stabilised soil columns was performed near Helsinki. The main results of tests were (1) reasonable values of the consolidation coefficients cvv and cvh were obtained by laboratory and in situ determinations, (2) all the drain types performed as expected, and there was no significant loss in drain effectiveness because of the relatively long (2 1/2 years) test period or the installation process used for geodrains and sand drains. (3) the equivalent diameter of the 4 X 100 mm prefabricated geodrains was found to be 5-7 cm. (4) for these soil conditions, displacement type sand drains can be designed using the size of the working tube as the equivalent drain diameter. (TRRL)

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  • Corporate Authors:

    Svenska Vag-Och Vattenbyggaren Riksforband

    Regeringsgaten 98
    S-11139 Stockholm,   Sweden 
  • Authors:
    • Leminen, K
    • RATHMAYER, H
  • Publication Date: 1979

Media Info

  • Features: Figures;
  • Pagination: p. 35-38
  • Serial:
    • Vag-Och Vattenbyggaren
    • Volume: 25
    • Issue Number: 7/8
    • Publisher: Svenska Vag-Och Vattenbyggaren Riksforband
    • ISSN: 0042-2177

Subject/Index Terms

Filing Info

  • Accession Number: 00311847
  • Record Type: Publication
  • Source Agency: Swedish National Road and Transport Research Institute (VTI)
  • Files: ITRD, TRIS
  • Created Date: May 21 1981 12:00AM