Case studies of rock slope instabilities associated to combined failure mechanisms
Professor Leandro R. Alejano
Our Society, increasingly dependent on technology, continues, however, to settle on the ground and critically depend on it. Recent studies show that in the period 2004-2016, 55,000 fatalities occurred worldwide, along with expenses of billions of euros, associated with slope stability problems not caused by earthquakes, most of them on mining and civil engineering slopes. Rock slope engineering was developed in the 1960s when 4 basic instability mechanisms were identified (planar, wedge, toppling and circular failure) and analytical techniques were proposed to compute stability. Even if a number of relevant advances were developed in the last decades, when a mining or civil rock slope is designed even today, the failure mechanisms typically analysed continue to be the four classic ones, and problems continues to occur. Our experience and recent studies suggest that some of these problems may not be associated with simple mechanisms, but they are produced by the combination of typically two of these mechanisms, or more. In this talk, a table with potential combinations of failure mechanism will be introduced and then 4 specific case studies will be reviewed with specific analysis including toppling-circular, wedge-toppling, wedge-circular and circular-toppling-planar combinations.
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Professor Leandro R. Alejano Professor of Rock Mechanics, University of Vigo, Spain
Prof. Leandro R. Alejano is a Professor of Rock Mechanics at the University of Vigo, Spain, where he has been an academic staff member since 1995 and became a full professor in 2020. His research focuses on rock engineering and its applications in mining and construction, including rock post-failure behaviour, dilatancy, tunnelling, subsidence, and underground excavations. His recent work examines rock slope engineering, particularly the stability of large granitic boulders, rockfall hazard management in quarries and mountain areas, and complex rock slope failures. A regular consultant for mining companies in Spain, he has published around 100 journal papers and over 100 conference papers. He currently serves as President of the Spanish Group of the ISRM, was VP Europe of the ISRM (2019–2023), and was Associate Editor of IJRM&MS (2013–2018).
For those unable to attend in person, the presentation will also be available via Zoom.
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