engleski

Remote monitoring of a landslide using an integration of GPS, TPS and conventional geotechnical monitoring methods

Case studies of monitored complex landslides presented in scientific papers are numerous but, owning to variability of landslide types and behavior, goals of investigation, field conditions and the ongoing technological development of monitoring sensors, no standardized approach regarding the setting up of a monitoring system can be adopted as an universally solution. The monitoring results should provide a basis for develop and validate confidential numerical models and adequate hazard management. There are a lot of examples used in landslides practice those used different techniques and different devices (sensors) to monitor landslides activity. The use of multiple devices (sensors) at same points and for the same purpose (equipment fusion) should be very useful to guarantee redundancy of measurements that can prevent loss of data if one instrument fails. Selection of the same position for different type of monitoring devices (sensors) will also enable spatial correlation of measurement data on the landslide surface and trough the landslide profile. Using of geodetical and geotechnical equipment fusion in combination with hydrological monitoring equipment, which should be consisted of pore pressure gauges and pluviometer or/and weather station, enable reconstruction of the relationship between rainfalls, groundwater level and appropriate landslide behavior as a basis for early warning system establishment. In beginning of the an early warning system establishment, the most important step is to link device measurement and possible failure mechanism and consequences those should following the sliding occurrence (the landslide risk). Based on presumptions described before, an advanced comprehensive monitoring system was designed and applied on the Grohovo landslide. The crucial role in equipment (and sensor fusion) selection was based on scientific requirements ; the equipment fusion request was based on consideration of possible ranges of monitored values and sensors precision. Establishment of an early warning system and defining of alarm thresholds should be based on existing cognition of the Grohovo Landslide behavior so as from collected comprehensive monitoring data. The focus of the early warning system establishment at the Grohovo Landslide must be on effective device combination (equipment fusion) results with respect to device malfunction detecting and reduction of false alarms in the future. Reliability of an early warning system is dependent on the weakest link in the system. The weakest link in the Grohovo monitoring system is power supply and data transmitting from the field PC, where all field data are collecting, to the control room at the Faculty of Civil Engineering University of Rijeka. In this paper the main ideas and advances of the monitoring equipment fusion so as weaknesses of the monitoring system at the Grohovo Landslide will be presented. Based on 18 months period of measurement results the weaknesses of existing monitoring system were located and necessary improvements are analyzed. Without these improvements, the future early warning system will be vulnerable and reliability of the system will be too low to use it as a practical application.

monitoring system; monitoring equipment; measurement results; early warning system

nije evidentirano