Probability of Failure
In RS2 you can carry out a probabilistic slope stability analysis (i.e. SSR slope stability analysis + probabilistic analysis).
When you run a probabilistic slope stability analysis, the following results will be displayed at the top center of the view:
- Mean Critical SRF (strength reduction factor)
- Standard Deviation Critical SRF
- Probability of Failure (PF)
Mean Critical SRF
The average critical strength reduction factor from all component files of the probabilistic analysis.
Standard Deviation Critical SRF
The standard deviation of the critical strength reduction factors from all component files of the probabilistic analysis.
Probability of Failure
The probability of failure is calculated from the Mean Critical SRF and the Standard Deviation of the Critical SRF assuming a normal distribution of critical strength reduction factors.
By default, the failure criterion is a strength reduction factor = 1 (i.e. the probability of failure is the probability that the critical strength reduction factor will be less than 1).
If you would like to use a value other than 1 for the failure criterion:
- Select Probability of Failure from the Statistics menu.
- Choose the second option in the dialog and enter a desired value in the edit box. Select OK.
- The Probability of Failure displayed at the top of the screen will now be the probability that the critical strength reduction factor is less than or equal to the value you have entered in the dialog.
See Tutorial 32 - Probabilistic Slope Stability Analysis for a discussion of these results.