Integrated fuzzy decision approach for reliability improvement of dam instrumentation and monitoring

Abstract Dams constitute a potential hazard to downstream life and property. Therefore, it is necessary to detect any signs of abnormal behaviour in structural safety. Monitoring of an embankment dam plays a key role to increase dam safety and to prove performances. Appropriate instrument selection is one of the most important steps of a monitoring plan. Inappropriate instruments may cause irreparable damages in critical situations. The lack of a method to analyse the instruments, and to select an appropriate one is one of the shortages of a monitoring plan. Nowadays, decision-making methods have been widely used to optimise the selection process. In addition, due to uncertainty in decisions, fuzzy methods are applied. The present study aims to establish an integrated decision model based on FAHP-FTOPSIS methods, by taking into account 9 influential criteria and 42 alternatives as geotechnical instruments. The model has been applied for a clay core embankment dam. Results showed that group decision-making can reliably be used to prioritise the instruments. For instance, the best instrument for monitoring stresses was hydraulic pressure cell while its closeness coefficient was .55. The possible choices were reliably selected and prioritised due to their adjacency to the ideal solution.