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Use of fully softened shear strength in slope stability analysis

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Abstract

Fully softened shear strength is an important empirical engineering concept for slope stability analyses of cuts in stiff clays and compacted embankments constructed of high-plasticity clays. This concept has been used to explain many first-time failures for which the back calculated shear strength is below the peak strength measured in the laboratory. A comprehensive review of case histories and laboratory studies related to fully softened shear strength was used to assess the application of this concept. The case history data were also used to provide guidelines on the soil types for which fully softened shear strength is appropriate, how and when this shear strength should be used in slope stability analysis, and how the fully softened failure envelope should be characterized. This paper contains specific guidelines on when and how the fully softened shear strength concept should be used in slope stability analyses.

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Author information

Authors and Affiliations

  1. CH2M, 2411 Dulles Corner Park Suite 500, Herndon, VA, 20171, USA

    Bernardo A. Castellanos

  2. Virginia Tech, 22 Patton Hall, Blacksburg, VA, 24061, USA

    Thomas L. Brandon

  3. Tennessee Tech, 1020 Stadium Drive, Box 5015, Cookeville, TN, 38505, USA

    Daniel R. VandenBerge

Authors
  1. Bernardo A. Castellanos
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  2. Thomas L. Brandon
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  3. Daniel R. VandenBerge
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Corresponding author

Correspondence to Bernardo A. Castellanos.

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Castellanos, B.A., Brandon, T.L. & VandenBerge, D.R. Use of fully softened shear strength in slope stability analysis. Landslides 13, 697–709 (2016). https://doi.org/10.1007/s10346-015-0597-y

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  • DOI: https://doi.org/10.1007/s10346-015-0597-y

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