A BEARING CAPACITY CORRECTION FOR STRAIN-SOFTENING SATURATED CLAYS

The idealised simple model used in the analysis incorporates the crucial feature under study of a form of soil strain-softening, giving solutions for modified collapse loads. Near collapse, shear strain beneath the footing mobilises pre-peak and post-peak shear stresses. Limiting equilibrium will be disturbed with a further increment in load. A simple design chart is presented for the use of the correction factor correlated with brittleness index and strain-softening index. Finite element analysis was carried out to obtain stresses and strains for discrete cumulative vertical displacement of the footing. Solutions were obtained for the load-displacement relationship for the footing ranging between the rigid plastic idealisations and residual undrained shear strengths. The correction factor, depending upon the bearing capacity obtained from the model, is used to modify the conventional equations for strip footings on saturated clays. The method requires a knowledge of true field post-peak stress-strain behaviour to be assessed from laboratory testing. A factor of safety on undrained shear strength partly compensates for the disparity between operational strength and the bulk strength measured in a test on a representative sample. (TRRL)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00174653
• Corporate Authors:

  Foundation Publications Limited

  7 Ongar Road
  Brentwood CM15 9AU, Essex,   England 
• Authors:
  • Kalteziotis, N A
  • Menzies, B K
  • Tarzi, A I
• Publication Date: 1984-7

Media Info

• Features: Figures; References;
• Pagination: p. 30-31
• Serial:
  • GROUND ENGINEERING
  • Volume: 17
  • Issue Number: 5
  • Publisher: EMAP CONSTRUCT LIMITED
  • ISSN: 0017-4653

Subject/Index Terms

• TRT Terms: Bearing capacity; Brittleness; Charts; Clay; Deformation; Deformation curve; Design; Design charts; Failure; Footings; Foundations; Laboratories; Loads; Mat foundations; Mathematical models; Mechanical strain; Mineral dislocations; Motion; Percent saturation; Safety factors; Saturated soils; Shear strength; Softening point; Strength of materials; Stresses; Undrained shear strength; Values in measurement
• Uncontrolled Terms: Correction (Mathematics); Strain softening
• Old TRIS Terms: Strains
• Subject Areas: Design; Geotechnology; Highways; Safety and Human Factors;

Filing Info

• Accession Number: 00393287
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, TRIS
• Created Date: Jun 30 1985 12:00AM