www.nat-hazards-earth-syst-sci.net/2/157/2002/ © Author(s) 2002. This work is licensed under a Creative Commons License. Possible deviations from Griffith’s criterion in shallow slabs, and consequences on slab avalanche release 1LTPCM – UMR, CNRS 5614/INPG-UJF, B.P. 75, F-38402 St. Martin d’Hères, France 2Sols, Solides, Structures, ENSHMG, B.P. 75, F-38402 St. Martin d’Hères, France 3ENSEEG, B.P. 75, F-38402 St. Martin d’Hères, France Abstract. Possible reasons for deviations from Griffith’s criterion in slab avalanche triggerings are examined. In the case of a major basal crack, we show (i) that the usual form of Griffith’s criterion is valid if elastic energy is stored in a shallow and hard slab only, and (ii) that rapid healing of broken ice bonds may lead to shear toughnesses larger than expected from tensile toughness experiments. In the case of avalanches resulting from failure of multi-cracked weak layers, where a simple Griffith’s criterion cannot be applied, frequency/size plots obtained from discrete elements and cellular automata simulations are shown to obey scale invariant power law distributions. These findings are confirmed by both frequency/acoustic emission duration and frequency/size plots obtained from field data, suggesting that avalanche triggerings may be described using the formalism of critical phenomena. Full Article (PDF, 473 KB) Citation: Louchet, F., Faillettaz, J., Daudon, D., Bédouin, N., Collet, E., Lhuissier, J., and Portal, A.-M.: Possible deviations from Griffith’s criterion in shallow slabs, and consequences on slab avalanche release, Nat. Hazards Earth Syst. Sci., 2, 157-161, 2002. Bibtex EndNote Reference Manager |
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