Multi-reinforcement of timber beams with composite materials: Experiments and fracture modeling

The interest of the multi-reinforcement of wood with composite materials is investigated both experimentally and by means of simulations. 3-meter-long concrete-wood beams with and without reinforcement are designed, fabricated and tested. Only a multi-reinforcement provides interesting results concerning the ultimate behavior. Several comments and results are provided. The authors propose an analytical tool to explain these experimental aspects, based on a model of multi-layered materials involving one stress field per layer (layerwise). The static model takes cracks and delaminations into account. Criteria of crack initiations in wood thickness and along the interfaces are proposed and experimentally identified. Finally the model allows the simulation of the fracture of a concrete/reinforced wood beam in bending and/or tension. The simulations appear very close to the experimental results and highlight the potential of the concept.