A study on wood beams strengthened by FRP composite materials

• Due to its great merits, Fiber Reinforced Plastics (FRP) composite was applied in retrofitting heritage buildings.
• GFRP rod and CFRP sheet were used to strengthen wood beams which are biologically damaged.
• From the four-point bending test, the average strength of the retrofitted beams increased compared to the Control specimens.
• Prestressing theory was applied to determine the resultant stresses on the wood beams under different loadings.
• A good correlation was found between the theoretical and experimental results.

Hollow-sectioned wood beams strengthened by Glass Fiber Reinforced Plastic (GFRP) rod and Carbon Fiber Reinforced Plastic (CFRP) composite sheets were proposed in the paper. Five groups of specimens with and without FRP reinforcement were tested. The four-point bending test was conducted to obtain the force–displacement relationships of the wood beams. The experimental results of the five groups of specimens were compared. A sectional analysis method was proposed to obtain the force–displacement relationships of these wood beams strengthened by GFRP rod and CFRP sheets. It is shown that the analytical results can reasonably predict the force–displacement relationships of these wood beams strengthened by GFRP rod and CFRP sheets.