Application of Modular Underground Monitoring System (MUMS) to landslides monitoring: evaluation and new insights

The paper describes the application of the Modular Underground Monitoring Sys-tem (further referred as MUMS) (Segalini et al., 2013) in two active landslides lo-cated in the Northern Italian Apennines. In particular, the aim of the paper is to demonstrate the efficiency and accuracy of the system and to examine the ad-vantages of an automated semi-continuous monitoring for the comprehension of the mechanical behavior of landslides, the definition of their triggering factors and the correct evaluation of their short term velocity. The mechanical behavior of slow moving landslides is generally evaluated on the basis of traditional surveys which are carried out at long time interval and therefore are lacking of detailed information about the links between triggering causes and mechanical effects. The main ad-vantage of an automated monitoring system resides in the observation frequency and in the simultaneous recording of several physical entities such as deformation, precipitation, pore pressure and so on. This large amount of data can be used for the numerical evaluation of the landslide behavior and for the definition of the most significant triggering cause(s). The obtained knowledge is of fundamental im-portance when there is a need of establishing an hazard threshold for the particular landslide and, when this assumption is made, the automated monitoring system can immediately become a real time control and alarm triggering device. For this pur-pose, it is important that the lifespan of the instrumentation is as long as possible, in relation with the expected displacements, in order to maintain the real time monitoring effective and economical as well as to build a reliable database for statistical analysis.