Modelling of a rapidly evolving rockslide: The Mt. de la Saxe case study

To model the temporal evolution of complex landslides, a 1D pseudo-dynamic visco-plastic approach, based on Perzyna's theory, has been conceived. In the original version of the model the viscous nucleus has been assumed to be bi-linear: irreversible deformations develop uniquely for positive yield function values whereas, in a more general case, even for negative values. In this work the model has been enriched by considering: i) an exponential viscous nucleus, ii) a strain-rate softening to reduce friction angle as sliding velocity increases and iii) block interaction forces to cope with complex 3D geometries for the sliding mass. The application of the proposed model to the La Saxe rockslide (Italy) clearly shows how a relatively simple model can be applied to a complex landslide by considering a spatial discretization of the sliding mass.