Investigating progressive slope failure by numerical modelling

The increasing occurrence of slope failure events (e.g. natural slope and embankment) are crucially threatening the resilience and sustainable development of cities worldwide, as they may cause significant damages to populations, buildings, public services and the environment.

In the UK, 10% of slopes are classified as at moderate to significant landslide risk, with more than 7% of the main transport networks located in these areas. Most of these slopes/embankments are in excess of 150 years old and do not offer comparable levels of capability and resilience to modern engineered slopes. They may fail after prolonged periods of wet weather or more intensive short duration rainfall events. Internationally, slope failure represents a major hazard to human life, property and lifeline facilities, infrastructures, and natural environment in most mountainous and hilly regions.

To date, the public awareness of slope failure risk is high, but our fundamental understanding of its progressive failure mechanism and countermeasures are still limited. This is mainly due to the difficulties in analysing the multiscale responses and characterize the spatial inhomogeneity of material properties of slopes. The fundamental scientific issue of these challenges is the weakening mechanism of inhomogeneous slopes at different scales as it determines the slope responses under various geological and environmental conditions. In this research “Multiscale and probabilistic modelling of progressive slope failure” supported by EPSRC, we will develop advanced numerical tools in a multiscale and probabilistic modelling approach to investigate the physic-mechanical mechanisms ruling the progressive failure of slopes and the subsequent landslide dynamics.

The proposed research has the potential to radically improve the current methodologies used in assessing the slope stability and landslide impact on infrastructures. The research will be extremely useful for producing efficient and reliable prediction and mitigation measures of slope failure hazards under changing environmental conditions.

Based on this research, it is hoped that engineering designs and constructions of various slopes can be more economic and reliable.

Publications

• Zhao, T., Liu, Y. A novel random discrete element analysis of rock fragmentation. International Journal for Numerical and Analytical Methods in Geomechanics, 2020, 44: 1386-1395. (DOI: 10.1002/nag.3067)
• Zhao T. *, Crosta G. B.. On the dynamic fragmentation and lubrication of coseismic landslides. Journal of Geophysical Research: Solid Earth, 2018, 123, 11, 9914-9932.
• Zhao, T.*, Crosta, G. B., Utili, S. & Dattola, G. Dynamic fragmentation of jointed rock blocks during rockslide-avalanches: insights from discrete element analyses. Journal of Geophysical Research: Solid Earth, 2018,123, 4, 3250–3269 (doi: 10.1002/2017JB015210)
• Zhao, T.*, Crosta, G. B., Utili, S. & De Blasio, F. V. Investigation of rock fragmentation during rockfalls and rock avalanches via 3-D discrete element analyses. Journal of Geophysical Research: Earth Surface, 2017, 122(3), 678-695.