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Báo cáo khoa học: "A new experimental device for rapid measurement of the trunk equivalent modulus of elasticity on standing trees"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: A new experimental device for rapid measurement of the trunk equivalent modulus of elasticity on standing trees. | 351 Ann. For. Sci. 57 2000 351-359 INRA EDP Sciences Original article A new experimental device for rapid measurement of the trunk equivalent modulus of elasticity on standing trees Jean Launaya Philippe Rozenbergb Luc Paquesb and Jean-Marc Dewitteb a ESEM 8 rue Leonard de Vinci 45067 Orleans Cedex 2 France b INRA Orléans 45160 Ardon France Received 15 July 1999 accepted 4 January 2000 Abstract - A new device has been developed in order to determine experimentally the modulus of elasticity of standing trees. Following preliminary trials on aluminum and steel beams its performances have been compared to the one of another equipment built according to the model proposed by Koizumi 1987 . Large-scale trials were then carried out on Douglas-fir and larch plantations of 72 and 292 trees respectively. Results showed that the new device described here allowed rapid assessments of the mechanical characteristics presented by populations of rather young trees i.e. less than 20 years old . Thus the data obtained with the device can efficiently be included in selection schemes along with other criteria. genetics modulus of elasticity standing tree douglas-fir larch Résumé - Un nouvel appareil pour la mesure rapide d élasticité equivalent des arbres sur pied. Un nouveau dispositif destine à la mesure du module d elasticite des arbres sur pied a été mis au point. Après l avoir teste sur des poutres en acier et en aluminium il a été compare à un autre appareillage construit sur le modèle de celui propose par Koizumi. Des essais à grande échelle sur des plantations de douglas 72 arbres et de mélèzes 292 arbres ont montré que ce dispositif permet de mesurer rapidement les caractéris-tiques mécaniques d une population d arbres assez jeunes moins de 20 ans et d effectuer efficacement une selection en prenant en compte ce critère parmi d autres. génétique module d élasticité arbre sur pied douglas mélèze 1. INTRODUCTION The use of wood as construction material requires a good .