Dynamics of the rock slope instability "Spitze Stei"

The rock slope instability "Spitze Stei" constitutes a risk for the touristic infrastructure around lake Öschinensee and the village Kandersteg. Our project task will investigate the mechanisms which led to the slope destabilisation and analyse scenarios for slope failures. We want to apply a thermo-mechanical model, which is fed with the rock-mechanical properties, meteorological forcing and the detailed rock kinematics of the instability. Laboratory experiments will be carried out to define strength and friction parameters of the rock under different degrees of water saturation. The kinematical model is established based on geodetical measurements and geomorphologic observations. Key Questions are: Did the observed permafrost thaw trigger the destabilisation of the slope? Can we reproduce the seasonal deformation signal of the last years? How will the instability react to extreme precipitation events? How critical is the current situation? What are realistic failure scenarios?