Identification of flexural performance of finger-jointed laminated timber beams reinforced with carbon fiber reinforced polymer
DOI:
https://doi.org/10.15587/1729-4061.2025.338430Keywords:
laminated timber, finger joint, carbon fiber reinforced polymer (CFRP), modulus of elasticity (MOE), modulus of rupture (MOR)Abstract
This paper presents the study of the mechanical performance of finger jointed laminated timber beams, unreinforced and reinforced with Carbon Fiber Reinforced Polymer, made from waste Merbau wood as an alternative to conventional structural materials. The present study focuses on the ultimate load capacity, modulus of elasticity, modulus of rupture, and load-deflection behavior of laminated beams with face butt and face finger joint orientations against solid beams. Tests were conducted by the four-point bending method according to ASTM D198-02. The results indicated that solid beams had the highest load bearing capacity compared to finger-jointed laminated beams. CFRP reinforcement increased the load capacity by 7.15% for face butt orientation and 38.58% for face finger orientation. CFRP reinforced face finger joints showed a significant increase in modulus of elasticity (MOE) and modulus of rupture (MOR) compared to face butt joints, indicating the effectiveness of CFRP reinforcement in certain orientations. Load-deflection analysis shows that CFRP-reinforced beams exhibit better ductility than unreinforced beams, with peak deflection increasing by 27.2% for face-butt and 26.0% for face-finger. Results confirm that CFRP reinforcement can enhance finger-jointed laminated beams; however, despite these improvements, the reinforced laminated beams still do not reach the strength level of solid beams, with the maximum load capacity and bending moment being approximately 31% of the solid beam values. This study offers insights into the development of robust, efficient, and sustainable wood-based building materials. Furthermore, the findings indicate that finger-jointed laminated wood, produced from waste cuttings from the wood processing industry, possesses the potential to be developed into structural building materials, thereby enhancing the value of wood waste
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