Pile Capacity in a Bouldery Stratum

A bridge was to be constructed across the Lohit River in India. The subsoil consisted of cobbles (80 to 300 mm size) and boulders (>300 mm size) with interspaces loosely packed with gravel (4.75 to 80 mm) and sand (0.075 to 4.75 mm). A soil boring could not be carried out due to the difficulty in making a 150 mm borehole and also as it would not yield any reasonable data. A shaft bore of 1700 mm diameter was made. A test shaft was provided with a steel liner for the full length of the shaft. Four reaction shafts (tension) were cast with liners only for the upper part of the shaft. During the first load test, there was excessive settlement. At the same time, the reaction shafts experienced very little movement. It was inferred that the steel liner prevented friction from developing in this medium. The liner was required to prevent collapse of the soil during boring, but not necessarily to the full depth. A second load test was conducted with a reduced length of liner, and there was a significant increase in the capacity of the shaft. The load test also showed plastic behavior of the medium. However the plastic was minimal in the vicinity of the design loads.


  • English

Media Info

  • Media Type: Web
  • Features: References;
  • Pagination: pp 453-463
  • Monograph Title: From Soil Behavior Fundamentals to Innovations in Geotechnical Engineering

Subject/Index Terms

Filing Info

  • Accession Number: 01522742
  • Record Type: Publication
  • ISBN: 9780784413265
  • Files: TRIS, ASCE
  • Created Date: Apr 22 2014 4:07PM