Full-size bending mechanical properties of Dahurian larch dimension lumber
Two groups of full-size Dahurian larch(Larix gmelinii) dimension lumber,which were visually graded,with different dimensions of 40 mm×90 mm×4 000 mm and 40 mm×140 mm×4 000 mm,had been edge-wise bending tested to get the modulus of elasticity(MOE) and modulus of rupture(MOR) according to Chi-nese Standard GB 50329-2002.The results showed that: 1) the MOE average values of 40×90 and 40×140 dimen-sion lumberⅠc,Ⅱc and Ⅲc were 15.0,13.0,13.2 and 15.7,14.0,15.6 GPa;the MOR characteristic values of 40×90 dimension lumberⅠc,Ⅱc and Ⅲc were 37.5,26.72 and 24.85 MPa;the MOR characteristic values of 40×140 dimension lumber Ⅰc and Ⅲc were 27.95 and 24.2 MPa;2)Ⅰc grade presented higher mechanical proper-ties as compared with other grades;3) The results showed a good relationship between MOR and MOE.The study of full-size larch dimension lumber bending mechanical properties provided a basis for the grading technology of domestic structural materials;it also provided parameters for structural material design applications.