ABSTRACT
The evolutionary failure processes leading to large-scale mass movements in massive crystalline rock slopes are the subjects of a multidisciplinary research project in the Swiss Alps. Focus is directed towards detecting and analysing rockslide processes that involve the progressive development of a failure surface as opposed to sliding along a pre-existing one. In order to monitor the underlying mechanisms of progressive failure, several new and conventional instrumentation systems were combined with an existing in situ monitoring program at an active rockslide site in the Valais (Switzerland). Design of the instrumentation network is based on site investigations and preliminary geomechanical models of the acting rockslide processes with respect to the rate of displacements, position and orientation of geological features that delineate the unstable rockmass. The network set-up considers additional findings from borehole logging and testing. Parameters that will be measured include microseismicity, fracture patterns and the temporal and spatial evolution of 3-D displacement fields and fluid pressures.
