8.3 A Note on Inter-Dependencies
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Fig. 8.8 Possible cross-section inter-dependencies. Spigotting line burst (burst tailings shown in
blue) can evolve into a dam break after Erosion, Sloughing and Stability (E.S.S) start developing
Fig. 8.9 Possible cross-section inter-dependencies. Local failures, -a- or -c-, can evolve into the
global -bAll of the above can be modelled using well known techniques such as Event
Tree Analyses (ETAs) and Failure Tree Analyses (FTAs) after determining each
elemental probability, for example, using the tables in Appendix A, or using loss
records, or integrating any available source to derive first estimates of the elemental
probabilities. Later on, there will be references and examples of this type of analyses.
8.3.2 Internal Dam Inter-Dependencies
Figure 8.9 shows a series of raises built upstream. We oftentimes see engineers
evaluate the global failure (slip surface b), and local failures (slip surfaces a and c). We
very seldom, if ever, see a stability analysis performed considering a domino failure,