HOW TO LIMIT THE SETTLEMENTS IN FILLS ABOVE PIPE LINE SYSTEMS. A PRELIMINARY SURVEY

FOEREBYGGANDE AV SAETTNINGAR I LEDNINGSGRAVAR. EN FOERSTUDIE

Four different projects were investigated. Test pits were made in previously filled trenches, settlements and repair costs were studied and time-settlement curves were worked out for a number of points. The settlement measurements show, as can be expected, that the greatest settlement occurs at the greatest trench depths. Just outside the trench the settlements are only 10-20 mm. The compression of the fill above the pipe line seems to be equal (5-15% relative compression) in the different layers of the fill. Thus there is very little friction between the fill and the natural soil. The determination of the density of the soil in the test pits shows that after some time the density of the fill is about equal to the density of the naturally deposited soil. The time-settlement curves show that an important part of the settlement develops in a short time (2-3 weeks) after the filling of the trenches. However, the settlements during thawing periods are also important. The costs of repair were between 90 and 165 sw CR per M of trench or between 16 and 25 sw CR per sqm of the street. As most of the settlements occur shortly after the filling, the cost of repair will be limited if the pipe line system is layed, say half a year before the street pavement. the interest costs are, in that case, half the above mentioned total cost of repair.

  • Availability:
  • Corporate Authors:

    Swedish Geotechnical Institute

    Fack
    S-581 01 Linkoping 1,   Sweden 
  • Authors:
    • Bergdahl, U
    • Fogelstroem, R
    • Larsson, K-G
    • Liljekvist, P
  • Publication Date: 1979

Language

  • Swedish

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00319616
  • Record Type: Publication
  • Source Agency: Swedish National Road and Transport Research Institute (VTI)
  • Files: ITRD, TRIS
  • Created Date: Jan 19 1981 12:00AM