Mechanical and Civil Engineering Seminar

Large catastrophic underwater landslides represent a major geohazard due to their devastating consequences and tsunami generation potential. Evidence of historic submarine landslide events shows, that these landslides can reach gigantic dimensions of many tens of kilometres in length at very low slope inclinations. It is highly unlikely that slip surfaces of such great length could appear simultaneously along their entire length. Therefore it is not surprising that conventional slope stability analysis methods fail to explain not only such large dimensions of these landslides, but also a broad variety of resulting geomorphological features.

In contrast, the proposed shear band propagation (SBP) approach treats slope failure as an evolution of growing slip surfaces and provides a rational quantitative explanation of the mechanisms associated with such enormous catastrophic landslide failures. Recent developments in the SBP approach within the BP Caspian Sea project provide simple mechanical criteria for different landslide stages. They have been validated numerically and experimentally and calibrated against the extensive geophysical and and geotechnical data from the Caspian paleo-landslides. This novel SBP approach has been implemented in collaboration with Fugro GeoConsulting into a GIS based probabilistic slope stability analysis framework, allowing for the risk assessment of the landslide impact on off-shore infrastructure.