Probabilistic Modeling of Tailings Embankment Designs. Volume I. Model Development and Verification.
Anderson-LR; Bowles-DS; Canfield-RV; Sharp-KD
NTIS: PB 83-122598 :233 pages
Traditionally, 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 were treated as deterministic quantities although they were known to be random variables. A pseudo-three-dimensional probabilistic slope stability model has been developed that treats shear strength as a random variable. The model uses the probability of a slope failure as an assessment of slope reliability. The model can accommodate zoned embankments of soil in which the strength is described by the mohr-coulomb strength envelope. Auto-correlation functions are used to describe the spatial correlation of the strength parameters, c and tan 0/. Model error can also be included in the analysis. Examples are presented to illustrate the influence of the choice of the soil strength variability parameters on the probability of failure. The results show that the critical failure surface based on the minimum safety factor are not necessarily the failure surface that will yield the maximum probability of failure. The analysis of the tailings dam shows that variance reduction can be large and that the model error is the dominant source of uncertainty for the embankment analyzed.
CP; Final Contract Report;
NTIS Accession No.
NTIS: PB 83-122598
Utah State University