[Zurück]

A. Preh:
"Rock Slopes: Detachment and Runout";
Technische Universität Wien / Fakultät für Bauingenieurwesen, 2017.

For hazard assessment of rock slopes, the failure or detachment mechanism and the possible runout has to be estimated. Detachment and runout are connected processes. An ideal model should therefore simulate both the failure mechanism and the runout. There are only very few "ideal" models for very special cases. For most cases we have to differentiate between a model for the failure mechanism and a model for the runout.
This habilitation report looks into investigations regarding analysis and modelling of the detachment and the resulting runout of rock slopes and valley flanks.
Any geotechnical analysis of landslides in rock should start with identification of the underlying failure mechanism. This should be effected by means of a catalogue of possible rock slope initial failure mechanisms (landslide types) comparing phenomena in the field and phenomena belonging to particular mechanisms.
The correct choice of a suitable calculation approach, and also installation of a proper monitoring system and finally, in addition, an assessment of hazard and risk are based on these primary
considerations.
Part I of this thesis discusses a suitable catalogue of initial failure mechanisms based on clearly defined mechanical models, as well as discontinuum mechanics models capable of modelling both the initial
failure mechanism as well as the change of mechanism at large displacements (post‐failure displacements). In addition, it demonstrates the interdependencies between failure mechanism,
monitoring and calculation approach in the example of two case studies.
Part II deals with the runout of rock slopes (rock fall, rock slide & rock avalanche) as a consequence of detachment. Rock fall process is discussed within the context of a research project, with the aim of
determining areas in which the danger of rock fall exists. 589 full‐scale drop tests were carried out in
ten different quarries (nine of which are in Austria and one in British Columbia, Canada), recording key parameters of rock fall trajectories. The stochastic nature of the process is discussed and a new dynamic model for analysis of rock fall and determination of hazard areas is presented.
Two numerical codes, the Distinct Element Model (PFC) and the continuum mechanics code (DAN), for analysis of rock mass falls (rock slides and rock avalanches) are presented. The two calculation
approaches are compared with back‐analysis of rock avalanches Punta Thurwieser (Italy) and Frank Slide (Canada). Their capability for the prediction of rock avalanche runout is discussed.

Rock slopes, failure mechanisms, runout, rock fall, rock avalanche, rock mechanics