Progress toward understanding complex rock slope failure mechanisms

With increased application of remote sensing techniques and three-dimensional numerical models the complexity of large landslides and rock slopes has become evident. The morphology of the landslide ground surface can now be investigated in detail even in heavily vegetated slope and used to constrain damage and numerical models. In this paper we show the importance of characterising sliding, lateral and rear release surfaces and realistically importing these surfaces into 3D numerical models. The contribution of brittle fracture of intact rock bridges and step-path lateral and sliding surfaces to rock slope failure mechanisms is illustrated. . Past rock slope/landslide models have considered failure growth through retrogression into the slopes, in itself a challenging process to model. We show how it is necessary to consider the growth of landslides both into and along the slope to capture the true progressive three-dimensional slope failure mechanism. We illustrate the importance of considering the detachment surface of rockfalls and the propagation of extensile and shear dominated rockfall mechanisms. The need to consider landform evolution and changing slope kinematics is demonstrated and potential methods discussed. for optimizing the use of rock slope/landslide “bigdata” sets reducing uncertainty.