폴리우레탄 접착제를 이용한 혼합 구조용집성판의 접착성능평가

Evaluation of Bonding Performance of CLT Using Mixed Species with Polyurethane Adhesive

To evaluate the bonding performance of the mixed cross laminated timber (CLT) us-ing the polyurethane adhesive, the face bonding test of layers between larch and yellow popular lamina was conducted. The mixed CLT was consisted of 5 ply which was the 3 major larch laminae and the 2 minor yellow popular laminae. The bonding test was measured according to the weight of adhesive and the clamping pressure. To verify the penetration of adhesive into cells, the microscopic properties of bonding layers was compared. The block shear strength and wood failure of mixed lamina was met the quality standard of EN (European standards). But The boiling water soaking delamination of the larch CLT was better than the mixed CLT which didn’t meet the EN standard. In larch lamina, the adhesive was mainly penetrated through the tracheid. On the other hand, in yellow poplar lamina adhesive was passed through-out to vessel and wood fibers. The glue line thicknesses of the MAa and MBa samples were about 102, 60.1 μm, for each.