ASSESSMENT AND CONTROL OF STABILITY FOR ROAD EMBANKMENTS CONSTRUCTED ON SOFT SUBSOILS

This report considers the problems of assessing the stability of embankments constructed on soft alluvial deposits of recent origin. Current methods for assessing stability are reviewed and the limitations and range of application of both the total and effective stress approaches to the problem are discussed. A major problem in assessing the stability is the determination of reliable values for the shearing strength of soft subsoils. The total stress method of analysis is sufficient for routine design purposes where an adequate factor of safety can be achieved economically, although there is evidence that this method may seriously over-estimate the stability. The effective stress method of anlaysis is more flexible but requires information on the porewater pressures in the subsoil and as these vary with time and applied loading they are difficult to predict reliably in variable deposits. However, the effective stress method linked with field measurements of porewater pressure has particular advantages where the stability of the completed works requires some gain in strength in the subsoil resulting from consolidation during the construction period. Stability charts based on a simplified method of interpreting the results of field measurements of porewater pressure have been successfully used at a number of sites for controlling the construction.

  • Corporate Authors:

    Transport and Road Research Laboratory

    Old Wokingham Road
    Crowthorne RG11 6AU, Berkshire,   England 
  • Authors:
    • SYMONS, I F
  • Publication Date: 1976

Media Info

  • Features: Figures; References;
  • Pagination: 35 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00139184
  • Record Type: Publication
  • Report/Paper Numbers: TRRL LR 711
  • Files: TRIS, ATRI
  • Created Date: Sep 16 1976 12:00AM