From Bureau of Economic Geology, The
University of Texas at Austin (www.beg.utexas.edu).
For more information, please contact the author.
Bureau Seminar, November 1, 2013
Link to streaming video: available 11.01.2013 at 8:55am
Assistant Professor of Civil and Environmental Engineering
The talk focuses on the relation between the unstable deformation of soil covers subjected to infiltration and the mobilization of flowslides in unsaturated shallow slopes. The purpose is to use concepts of material stability to elucidate the mechanics of such slope failures and explore their relation with the fluctuation of the pore pressure regime. The presentation discusses a unified framework based on: (i) a mechanistic theory to capture material instabilities in unsaturated soil covers, (i) a soil model able to reproduce liquefaction and wetting-induced collapses and (iii) a simplified methodology for quantifying triggering perturbations in shallow slopes. The presentation illustrates the role of specific properties of the deposits, such as strength, plastic compressibility and fluid-retention characteristics. It is shown that the coupling between these properties controls the values of slope angle and thickness at which the covers become susceptible to a runaway failure. The analyses suggest that, within such a range of inclinations, flow failures can be triggered by a chain process consisting of volumetric collapse, sudden saturation of the pores and, eventually, catastrophic liquefaction.
Giuseppe Buscarnera is Assistant Professor of Geotechnical Engineering at Northwestern University – Department of Civil and Environmental Engineering, which he joined in September 2011. He received his B.Sc. (2004), M.Sc. (2006) and Ph.D (2010) all in Civil Engineering from the Politecnico di Milano, Italy. During his doctoral and post-doctoral studies he has collaborated with several academic institutions, such as the Universitat Politecnica de Catalunya, the Massachussetts Institute of Technology and The University of Sydney. His research focuses on geomechanical modeling, an in particular on the theory of material stability, the multiphysics of porous media and the application of geomechanics to landslide hazard zonation and energy geomechanics.