Numerical modelling of a slowly creeping landslide in crystalline rock - a case study

Glacial erosion brings many alpine valleys to limit equilibrium because of the steepened valley flanks. Instable slopes hold potential dangers, even though slowly creeping landslides as treated below can be observed and do seldom show surprising behavior as long as they do not accelerate. Nevertheless a sudden loss of stability can lead to uncontrollable movements with much higher velocities. Aim of the project presented here is to gain a better understanding of mass movements and the influences of different boundary conditions on slope displacement. A well monitored example for a slowly creeping landslide is the mass movement Hochmais -Atemkopf, situated in the Kaunertal, Tyrol, Austria. Based on a geological model a calculation model including four sliding masses has been developed. In addition, external effects were also taken into account to get a idea of their possible influences on stability and deformation. This paper presents a limit equilibrium analysis and the preliminary results of a numerical finite element study.