Bending properties of dimension lumber produced from Siberian larch (Larix sibirica) in Mongolia

Abstract

Abstract The modulus of elasticity (MOE) and modulus of rupture (MOR) were evaluated for 190 pieces of dimension lumber (2 by 4 lumber, 38 by 89 mm in cross-section) produced from Larix sibirica trees grown in Mongolia. The 5% tolerance limits of the MOE and MOR were 5.70 GPa and 15.1 MPa, respectively. The value of the 5% tolerance limit of the MOR exceeded the characteristic value of 2 by 4 lumber in visual grading class No. 3 of the Japanese Agricultural Standard for the D. fir-L, Hem-Tam, JS-III and S-P-F softwood species groups. A significant positive correlation was found between the MOE and MOR, although air-dry density was weakly correlated with bending properties in L. sibirica.

Keywords

• Larix sibirica
• Modulus of elasticity
• Modulus of rupture
• 5% tolerance limit
• Visual grading
• Juvenile wood