The basic concepts and elementary mechanical principles of the limit equilibrium procedure for stability analysis are reviewed, and a limit equilibrium method is presented (with examples) for computing the internal stresses and the average factor of safety of slopes, using shear surfaces of any shape. The general applicability of the proposed method for solving slope stability, earth pressure, and bearing capacity problems is illustrated. Only plane strain or axisymmetrical stress conditions are considered. The axisymmetric case is used only for interpretation of the results of triaxial tests. Classical knowledge about equilibrium stresses in soil elements are reviewed, and principles and formulas describing 2-dimensional failure conditions for ideal soils are summarized. The principles of stress-vector curves are discussed, and their application to the interpretation of shear tests on soil samples is illustrated. The shape and location of classical failure surfaces and the corresponding state of stress is derived, and the differences between ideal plastic and ideal brittle failure is demonstrated. The paper also illustrates the application of limit equilibrium principles in obtaining information about the stress conditions at limit equilibrium and the shape of the shear surface corresponding to minimum safety factor. The generalized procedure of slices is described which can be used to: solve stability problems for irregular topography, and layered soils of different shear strengths, using shear surfaces of any arbitrary shape; explore a statically reasonable state of stress both along the shear surface itself and within the body of soil located above that surface; and unify the treatment of such categories of soil stability problems as earth pressure, bearing capacity, and slope stability.

  • Corporate Authors:

    John Wiley & Sons, Incorporated

    111 River Street
    Hoboken, NJ  USA  07030-6000
  • Authors:
    • Janbu, N
  • Publication Date: 1973

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Filing Info

  • Accession Number: 00096414
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jul 15 1975 12:00AM