Shear reinforcement of wood using FRP materials

A study of the mechanical behavior of wood members either reinforced or strengthened with fiber-reinforced plastic (FRP) materials in the form of sheets (laminates or fabrics) externally bonded to the shear-critical zones is presented in this paper. The analysis is described first for the (short-term) behavior of shear-reinforced wood members, followed by parametric studies to assess the effect of the type and amount of FRP reinforcement on the response of wood-FRP members. It is shown that the effectiveness of FRP reinforcement can be quite high, and that it is maximized when the fibers are placed in the longitudinal direction and the height of externally bonded sheets is just a little higher than a limiting value, beyond which FRP failure precedes wood failure. In the experimental part of the study, 21 wood beams designed to fail in shear are reinforced with carbon-FRP fabrics at various configurations and area fractions and tested to failure. The agreement between experiments and analysis, in terms of shear capacity, was found to be quite satisfactory.