STABILITY OF AN EMBANKMENT ON A PARTIALLY CONSOLIDATED FOUNDATION

A test fill was built on a section of embankment north of Boston with the objective of determining the appropriate strength parameters of Boston Blue Clay for stability analyses. Predictions of the fill elevation to cause failure, made before the field test begin, are based on Unconfined Compression, Unconsolidated Undrained triaxial, field vane and SHANSEP (Stress History and Normalized Soil Engineering Properties) undrained strengths. The Simplified Bishop and the Morgenstern-Price procedures of stability analyses are utilized for the predictions which are compared with the actual field test results. The test fill failed at an elevation of +56.5 ft after adding 18.7 ft of fill to the five year old embankment. The field instrumentation was not as successful in warning against impending failure as was expected. The only consistent but very conservative sign of instability was provided by the settlement plates. The uncorrected field vane and SHANSEP yielded the most accurate predictions of stability. The field vane prediction was 51.5 ft (9.0% underestimate) and the SHANSEP prediction was 60.7 ft (7.4% overestimate). The UC and UU strength were much too low, underestimating the failure elevation by 33%.

  • Supplemental Notes:
    • Prepared in cooperation with DOT and FHWA.
  • Corporate Authors:

    d Facilities Division

    77 Massachusetts Avenue
    Cambridge, MA  United States  02139

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590

    Massachusetts Department of Public Works

    Research and Materials Section, 99 Worcester Street
    Wellesley Hills, MA  United States  02181
  • Authors:
    • Silva-Tulla, F
    • Marr, W A
    • Lambe, T W
  • Publication Date: 1976-3

Media Info

  • Pagination: 126 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00141045
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWA-RD-76-S0501 Tech. Rpt.
  • Contract Numbers: R12-2
  • Files: NTIS, TRIS, USDOT
  • Created Date: Oct 6 1977 12:00AM