An injection hose is a perforated hose that is cast into or along a construction joint in concrete in advance, so that the joint can later be made watertight with an injection material. It is a preventive system to avoid or repair leakage through the seam between two concrete pours.
How does it work?
In large concrete structures not everything is poured at once. At the transition between an older and a newer pour a construction joint is created, a weak spot through which water can penetrate. The injection hose is placed exactly on this seam and cast in. The ends remain accessible. If the joint later leaks — or as a precaution — an injection material (for example a resin or a cement-based gel) is pressed through the hose under pressure. That material emerges through the perforations and fills the seam, sealing it.
Application
- Basements and tanking structures — sealing construction joints in underground, water-retaining concrete structures
- Foundations and retaining walls — joints that lie below the groundwater level
- Tunnels and car parks — where leakage is not acceptable
- Swimming pools and water tanks — sealing seams on the water-retaining side
Points to note
- The hose must be fixed accurately onto the joint before pouring and must not be damaged
- The injection points must remain accessible and identifiable
- Some systems can be injected once, others are reusable; choose according to the application
Related terms
- Concrete injection
- Expansion joint
- Water barrier
- Basement
- Concrete
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