The fuzziness and sensitivity of failure probabilities

  • Michael Oberguggenberger
  • Wolfgang Fellin


In this article, we scrutinize basic issues concerning the interpretation of probability in the probabilistic safety concept. Using simple geotechnical design problems we demonstrate that the failure probability depends in an extremely sensitive way on the choice of the input distribution function. We conclude that the failure probability has no meaning as a frequency of failure. It may supply, however, a useful means for decision making under uncertainty. We suggest a number of alternatives, as interval probability, random and fuzzy sets, which serve the same purpose in a more robust way.


Failure Probability Triangular Fuzzy Number Direct Shear Test Limit State Function Interval Probability 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Michael Oberguggenberger
    • 1
  • Wolfgang Fellin
    • 2
  1. 1.Institut für Technische Mathematik, Geometrie und BauinformatikUniversität InnsbruckAustria
  2. 2.Institut für Geotechnik und TunnelbauAustria

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