Exploration analysis for landslide risk management

Risk management for landslides involves, in addition to active and passive countermeasures, the collection of information through exploration. With such information, it is possible to reduce uncertainties, make more reliable decisions and therefore reduce risk. This paper addresses two types of exploration, namely (1) exploration (information collection) after the decision to obtain additional information is made, which is the standard type of exploration, and where one uses the new information to update risk, and (2) exploration (information collection) before the decision to obtain additional information is made, in which one conducts ‘virtual exploration’ to establish if exploration is worthwhile. The paper shows that both types of exploration can be assessed using either decision trees or Bayesian networks. Both approaches were applied to the Walton’s Wood Landslide in England using infinite slope analysis and produced consistent results. The interested user can, based on what is documented in the paper, select and apply either one or both of the approaches.