Effects of knot area ratio on the bending properties of cross-laminated timber made from Korean pine

Abstract The effect of knot clusters on the bending properties Korean pine ( Pinus koraiensis ) cross-laminated timber (CLT) was analyzed to increase utilization low-quality lumber. laminae used manufacture CLT were classified into five groups, four major layer and one minor group, by mechanical grade area ratio (KAR) lamina. Out-of-plane tests conducted made from each group. modulus elasticity (MOE) manufactured closely correlated with MOE individual axis In case rupture (MOR) CLT, KAR in more significantly affected than MOE. main finding is that lower fifth percentile MOR value specimens large knots (KAR > 0.5) higher acceptable reference E3 (ANSI/APA PRG 320) a similar lamina grade. Therefore, use lumber can be expanded under condition limitation greater KAR.