In collaboration with the Fondazione Montagna Sicura, Michel Jaboyedoff, Antoine Guerin and Li Fei went to Entrèves (Aosta Valley, Italy) on 23 October 2018 to investigate the 1997 Brenva rockslide scar (3’870 m, Mont-Blanc massif), which reactivated in September 2016. A helicopter flight of about 25 minutes allowed acquiring hundreds of pictures (digital and thermal) of the rock mass in exceptional conditions, as the high mountain was dry in late autumn 2018. A high-resolution Structure-from-Motion model was then generated using these pictures, allowing us to analyze in detail the structural features and rockfall activity of the Sperone della Brenva.
Part of the Risk Analysis Group participated to the International Symposium on Rock Slope Stability 2018 in Chambéry, France, on 13 to 15 November 2018. It was a great opportunity to exchange about many topics related to natural hazards and rockfalls. The group presented two contributions as first authors whose titles are below:
- About the “rockfall” failure hazard assessment. Michel Jaboyedoff et al.
- Coupling 3D rockfall propagation to the spatio-temporal frequency for a realistic rockfall hazard mapping. Cécile D’Almeida et al.
The symposium concluded with very interesting field visits where we did learn about the history of the Mont Granier and its previous rock collapses and about the different instabilities that affects the gorges of Arly and how the local institutions manage them.