Citation

Sharp KD, Anderson LR, Bowles DS, Canfield RV. Transp. Res. Rec. 1981; 809: 70-78.

Copyright

(Copyright © 1981, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

Traditionally, an evaluation of the safety of slopes has been based on computing a safety factor against failure. In computing the safety factor, the geometry of the slope, the soil parameters, and the pore pressures are treated as deterministic quantities even though they are known to be random variables. Vanmarcke has developed a three-dimensional probabilistic slope-stability model that treats shear strength as a random variable. The model uses the probability of a slope failure as an assessment of slope reliability. A probabilistic slope-stability model that is an extension of Vanmarcke's model is presented. The model can accommodate zoned embankments of soil in which the strength is described by the Mohr-Coulomb strength envelope. Autocorrelation functions are used to describe the spatial variation of the mean and standard deviation of the strength parameters, c and tan phi. Several examples are presented to illustrate the influence of the choice of the statistical soil parameters on the probability of failure. The results show that the critical failure surface based on the minimum safety factor is not necessarily the failure surface that will yield the maximum probability of failure.