Method for reinforcing a civil engineering structure
The invention relates to a method for reinforcing a civil engineering structure, comprising the following steps: —coating a surface of the structure with a first layer of resin in a fluid state, having a particle size distribution, termed first particle size distribution, —applying a layer of a dry woven fabric with a weight per unit area greater than or equal to 600 g/m2, termed high-grammage woven fabric, to the coated surface while the resin is still in the fluid state, by exerting on the woven fabric a pressure sufficient to impregnate it with resin, —coating the woven fabric with a second layer of resin, termed closure layer, in a fluid state, having a particle size distribution, termed second particle size distribution, which is less than or equal to the first particle size distribution.
1. A method for reinforcing a civil engineering structure, the method comprising:
coating a surface of the structure with a first layer of resin in a fluid state, the first layer of resin having a first particle size,
with the resin still in the fluid state, applying a layer of dry fabric, having an areal weight greater than or equal to 600 g/m 2 , to the coated surface, while applying to the dry fabric sufficient pressure to impregnate the dry fabric with resin,
coating the fabric with a second layer of resin in the fluid state, the second layer of resin having a second particle size less than the first particle size.
2. The method as claimed in claim 1 , wherein the first layer of resin in the fluid state comprises resin in the form of a gel.
3. The method as claimed in claim 1 , wherein resin of at least one of the first and second layers of resin contains a thickener.
4. The method as claimed in claim 1 , wherein the fabric comprises fibers having interstices, the first particle size and the second particle size being strictly smaller than the interstices.
5. The method as claimed in claim 1 , wherein the first particle size is less than or equal to 1 μm.
6. The method as claimed in claim 5 , wherein the first particle size is less than or equal to 0.1 μm.
7. The method as claimed in claim 1 , wherein at least one of the first and second layers of resin contains granular elements comprising nanoparticles.
8. The method as claimed in claim 1 , wherein resin of at least one of the first and second layers of resin has a Brookfield viscosity at 23° C. giving a shear rate of 15 to 25 Pa·s for a rotational speed of 1 s −1 and of 3 to 5 Pa·s for a rotational speed of 10 s −1 .
9. The method as claimed in claim 1 , wherein inert granular elements or fillers are added to at least one of the first and second layers of resin in a proportion between 2% and 12% by weight.
10. The method as claimed in claim 9 , wherein said proportion is between 5% and 10% by weight.
11. The method as claimed in claim 1 , wherein at least one of the first and second layers of resin contains granular elements comprising silica.