Injection of epoxy compounds in bridges or in bricks, stone or concrete can be made for two purposes:
- consolidate mortar beds between ashlars, blocking cavities and cracks;
- create a continuous, waterproof cover which prevents external water from percolating inside.
Injections can be made both extrados and intrados: the latter is more frequent because operating from the extrados requires blocking traffic (vehicular and railway) and removing the material between the roadway and the actual vault.
Waterproofing is another very important operation to maintain the static features of a vault or an arch: the water that from the extrados penetrates between the ashlars, whether in stone or brickwork, produces a crumbling effect which can be severe when it freezes over in winter and its volume increases.
Injection from the extrados
It’s the less frequent case. In case of injections, holes at a depth of ¾ the vault thickness are made. We then use a piston pump with separate tanks for resin and hardener (see picture) and a static mixer at the front.
Injection from the intrados
It’s the most frequent case. This type of operation is frequently required when it is not possible to operate from the extrados of the bridge (e.g. railway bridges and more in general bridges which cannot be closed to traffic). Injection is carried out with INJECTOMIX equipment or alternatively with a pump capable of injecting a considerable amount of cementing product, RESISYSTEM 310 e/o 312. Holes are made through all the thickness of the vault, especially if the purpose is also to waterproof. This way we can create a continuous cover between the filling material and the vault which prevents water from entering.
Products to reinforce bridges:
Consumption:
Seeing as we cannot see inside the crack, we cannot assess possible cavities or other cracks which spread from the crack. Therefore consumption cannot be estimated. Please refer to the specific gravity which for REPIKIT 310 and RESISYSTEM 310 is of 1.05 kg/dm3, whereas for REPIKIT 312 and RESISYSTEM 312 it is of 1.2 kg/dm3.