Brunner, Philip

2018-7, Kukemilks, Karlis, Wagner, Jean-Frank, Saks, Tomas, Brunner, Philip

This study explores the potential of integrating state-ofthe- art physically based hydrogeological modeling into slope stability simulations to identify the hydrogeological triggers of landslides. Hydrogeological models considering detailed morphological, lithological, and climatic factors were elaborated. Groundwater modeling reveals locations with elevated pore water pressures in the subsurface and allows the quantification of temporal dynamics of the pore water pressures. Results of the hydrogeological modeling were subsequently applied as boundary conditions for the slope stability simulations. The numerical models illustrate that the hydrogeological impacts affecting hillslope stability are strongly controlled by local groundwater flow conditions and their conceptualization approach in the hydrogeological model. Groundwater flow itself is heavily influenced by the inherent geological conditions and the dynamics of climatic forcing. Therefore, both detailed investigation of the landslide’s hydrogeology and appropriate conceptualization and scaling of hydrogeological settings in a numerical model are essential to avoid an underestimation of the landslide risk. The study demonstrates the large potential in combining state-of-the-art computational hydrology with slope stability modeling in realworld cases.

2017-9, Kukemilks, Karlis, Wagner, Jean-Frank, Saks, Tomas, Brunner, Philip

This study uses two approaches to conceptualize preferential flow with the goal to investigate their influence on hillslope stability. Synthetic three-dimensional hydrogeological models using dual-permeability and discrete-fracture conceptualization were subsequently integrated into slope stability simulations. The slope stability simulations reveal significant differences in slope stability depending on the preferential flow conceptualization applied, despite similar small-scale hydrogeological responses of the system. This can be explained by a local-scale increase of pore-water pressures observed in the scenario with discrete fractures. The study illustrates the critical importance of correctly conceptualizing preferential flow for slope stability simulations. It further demonstrates that the combination of the latest generation of physically based hydrogeological models with slope stability simulations allows for improvement to current modeling approaches through more complex consideration of preferential flow paths.