Laghdir Aziz, Jullien Delphine, Gril Joseph, Thibaut Bernard.
1999. Modelling growth-stresses related radial cracks in logs.
In : Third Workshop on Connection between Silviculture and Wood Quality through Modelling Approaches and Simulation Software, La Londe-Les-Maures, France, September 5-12, 1999. Nepveu G. (ed.); IUFRO; INRA
Résumé : The most visible consequence of growth stresses in trees is the log-end splitting appearing after felling the tree or crosscutting the trunk into logs. In hardwoods especially, this is a major drawback regarding to the subsequent cutting operations or the use of the log as a round wood. The modelling proposed is based on an energetic analysis of the crack propagation process. Assuming a given initial state of residual stress in the stem and a given shape of the crack surface, the amount of elastic energy released by the cracking process can be evaluated. At every stage of the propagation, the released energy has to be greater than the cohesion energy of the newly cracked surface. Since the cohesion energy per unit area, or toughness, is a quantity characteristic of the material, this criterion allows to predict the cracking risk of a species, or a variety. In this paper a finite element modelling yielding the calculation of released energy will be presented. Validation will be proposed using data obtained on Eucalyptus. A typical asymmetric distribution of growth stresses will be assumed and various patterns of radial cracking will be compared.
Classification Agris : K50 - Technologie des produits forestiers
Auteurs et affiliations
- Laghdir Aziz, USTL [Université des sciences et techniques du Languedoc] (FRA)
- Jullien Delphine, USTL [Université des sciences et techniques du Languedoc] (FRA)
- Gril Joseph, USTL [Université des sciences et techniques du Languedoc] (FRA)
- Thibaut Bernard, CIRAD-FORET-BOIS (FRA)
Autres liens de la publication
Source : Cirad - Agritrop (https://agritrop.cirad.fr/538352/)
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