Observation of triggering factors and development of landslides by borehole tiltmeters on the high bank of the river danube in dunaszekcső, hungary: A case study

Abstract

In Hungary the high loess banks along the west side of the River Danube are prone to landslides that cause a lot of damage. Several landslides have occurred in Dunaszekcső. In August 2007 the commencement of a slow sliding process was visually observed here and two borehole tiltmeters were installed in the dangerous area. One instrument was placed on the stable part and the other on the unstable part of the high loess wall. A large landslide occurred here on 12 February 2008, so the whole sliding process was recorded by the tiltmeters. The instrument on the sliding part of the high bank was reinstalled one year after the slump because of the large movements. The tiltmeter on the stable part was working continuously and so the processes by which the high bank tried to keep its balance were recorded. However, the high bank did not come to an equilibrium state and in 2010 a new crack appeared about 8–10 m from the 2008 slide headwall. The recorded tilt is similar to the tilt process before the first slump. Besides tilt measurements, the water level of the River Danube, the ground water table, and the ground and air temperature were also monitored. The potential evapotranspiration of the area was also determined to study the effect of the vegetation. This paper presents the tilt processes and the relationships between tilt and hydrological and meteorological parameters.