Discontinuum modelling of slope instability as a support tool for risk management

The definition of threshold values within an early warning system for monitoring of an instability phenomenon in nearly real time represents a key step. Several approaches exist in literature, among which numerical modelling for the simulation of instability scenarios is the least common. The present paper illustrates how discontinuum numerical modelling can be used as a support tool for risk management with reference to a slope instability case study. The aim is to investigate the displacement rate that can anticipate the instability phenomena. To highlight the reliability of the models, back-analysis of a past instability event is carried out and a time-scaling coefficient is defined, and eventually validated, to match numerical results and monitored data. Based on such results, that reproduce the slope displacement trends from triggering to collapse, thresholds and related timespans to be adopted within the existing monitoring system are suggested.