Carbon reinforcements

Wooden structures are always used, whether during restorations or in building. Wood is a material with a long building tradition. Historical city centers feature lots of examples of its use from any period, but wood is also a modern material thanks to the performance/weight ratio which makes it possible to build quickly and gives the construction industry a more industrialized nature.

More specifically, the use of synthetic fibers (carbon and glass), also known as fiber-reinforced polymers (frp), to reinforce wooden beams during restorations has become noteworthy. Structural adjustment operations which use carbon fibers have two main purposes:

- reduce the magnitude of the camber on inflected floors;
- recover/improve tensile strength of truss chains.

Their use has several advantages compared to the old restoration techniques which instead require the use of thin sheets and/or steel rods:

• the structure is reinforced with no weight added (opposed to what happens with steel reinforcements);
• carbon straps are light, do not hamper and are easier to take on a scaffolding;
• a more effective reinforcement is achieved with reduced labor;
• carbon reinforcement is not subject to corrosion nor it attracts damp

The adhesive which is normally part of the frp matrix is essential to ensure the effectiveness of the reinforcement operation. Epoxy resins are particularly suitable for gluing and impregnation of carbon fibers:

• hardening with shrinkage lower than 0.1 %;
• little sensitive to damp;
• structural adhesion to wood; excellent fiber impregnation.