Experimental and Numerical Study on Strengthening Timber Beams Using Carbon and Glass Fibers

This research investigates the flexural behavior of laminated spruce timber beams strengthened with carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP) composites. A total of 28 specimens, fabricated in accordance with TS EN 408+A1 standards, comprising twelve CFRP reinforced, twelve GFRP reinforced, and four unreinforced control beams, were subjected to four-point bending tests. Three distinct reinforcement configurations rods, plates, and fabrics were systematically applied and comparatively evaluated. The results consistently demonstrated that CFRP reinforcements significantly outperformed GFRP counterparts in enhancing stiffness and flexural strength. Among the reinforcement types, double carbon rods and wide CFRP plates exhibited the most pronounced improvements, while spiral-wrapped CFRP fabrics showed superior performance relative to flat fabric applications. Additionally, the study highlights the critical influence of reinforcement configuration on the mechanical response of timber beams and underscores the impact of inherent wood defects on experimental outcomes. Complementary numerical simulations conducted using ANSYS software corroborated the experimental findings, thereby validating the effectiveness of the proposed reinforcement strategies for timber rehabilitation.