• Yo-Jin Song Kangwon National Univ., Republic of Korea.
  • In-Hwan Lee
  • Da-Bin Song
  • Soon-Il Hong


Cross-laminated timber (CLT), Japanese larch, composite CLT floor, delamination test, bending strength, carbon fiber reinforced plastic (CFRP).


To develop a high-performance, lightweight cross-laminated timber (CLT) floor, this study tested the delamination performance between carbon fiber-reinforced plastic (CFRP) and CLT and the bending performance of a CFRP composite CLT that was differently reinforced according to the shape of CFRP. The test results showed that the soaking and boiling delamination between CLT and CFRP of the CFRP composite CLT produced by spreading a polyurethane (PUR) adhesive at 300g/m2 were both less than 5%, satisfying the Korean standard. Furthermore, the composite CLT (3ply) of which the entire outer surface of the tension laminae was reinforced with a CFRP plate (thickness: 1.2 mm) showed a mean MOE and a mean MOR higher by 27% and 48%, respectively, than those of the unreinforced CLT (3ply). Furthermore, even though the weight of this CFRP composite CLT was smaller than that of 5ply CLT by approximately 40%, its bending moment was measured higher by 14% than that of the 5ply CLT (thickness: 175 mm) fabricated by limited state design (LSD) as specified in PRG-320.


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Research Contributions