The Kostanjek landslide - Monitoring system development and sensor network

Abstract

Kostanjek landslide is the largest landslide in the Republic of Croatia. It is located in the western part of the City of Zagreb, in residential area at the base of the south western slope of Mt. Medvednica. Investigation of this landslide is one of the objectives of the Japanese-Croatian five-year (2009-2014) scientific joint-research project ‘Risk Identification and Land-Use Planning for Disaster Mitigation of Landslides and Floods in Croatia’. The aim of investigation is to check and improve existing landslide model and to establish landslide monitoring system aimed at landslide risk mitigation. A comprehensive, real time monitoring system was designed during the period of 2010 and 2011, installation of equipment started in October 2011, while the completion of works will be finished during the 2013. Monitoring system consist of geodetic, geotechnical, seismological and hydrological equipment. Geodetic equipment includes 15 GNSS stations, geotechnical equipment includes 9 extensometers at five different locations and one 100 m borehole with inclinometer casing. Pore pressure gauges will be installed in borehole during 2013, at the central part of landslide, at three different levels. Seismological monitoring consists of 7 accelerometers installed at five different locations. Hydrological equipment consist of two weirs with water level sensors for measuring discharge, rain gauge and two water level sensors installed in two domestic wells. Aim of this paper is to present design of planned monitoring system, what has been done so far and to present initial monitoring data from installed equipment.