Repairing wood beams under bending using carbon–epoxy composites

Abstract Repair of wood damaged beams under bending using carbon–epoxy composites has been studied in this work. The influence of patch thickness and adhesive filleting was analyzed experimentally and numerically. The main goal was to assess the effect of these parameters on the ultimate load and failure type. Numerical analyses considering a mixed-mode cohesive damage model were performed in order to better understand the physical phenomena which explain the observed behavior. The main conclusion is that repairing leads to a remarkable gain on the bearing capacity of the damaged beam. Additionally, it was observed that a slight increase on the ultimate load can be obtained by diminishing the patch thickness. However, adhesive filleting did not induce a clear increase on the load bearing capacity, which was explained by the failure mode observed in this case.

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