SPACIAL DISTRIBUTION OF RISK AND RELIABILITY IN SLOPES

Vageesha S. Mathada

Abstract: In conventional risk analysis, maximum probability of failure, pf, obtained from reliability analysis is used to compute risk. There will be a single value of reliability index (or pf) and hence a single value of risk (product of pf and cost of damage) for the entire slope. The assumption of cost of damage to be a constant leads to a single value of risk. Even the single value of reliability index does not provide any insight to the safety of the entire slope. More the volume of the slip mass more would be the cost of damage. Since the reliability index shows a flat minimum similar to factor of safety within the slope, chances of failure occurring near the vicinity of the minimum reliability surface cannot be completely ruled out. This implies that risk and reliability are no longer single values. In this paper an attempt is made to plot the safety and risk maps for a given slope. From the results it is clear that the maximum risk surfaces are different for different cost functions. The developed maps become practically useful to decide the extent of remedial measures.

Keywords: Risk, Reliability, Safety Map, Spatial Distribution, Slope stability

DOI: https://doi.org/10.15623/ijret.2014.0315118