Leaks in concrete, brick or sheet pile structures can be sealed by injection. Cracks, construction joints and gravel nests and the like can cause leakage. The cracks are generally drilled obliquely with a rotary hammer. The bore hole must then be cleared of dust. An injection nipple is then placed in the borehole. This can be a blow, screw or sticky clip. Subsequently, injection fluid is pressed in under low or high pressure and the crack is filled. Depending on the object to be injected, the injection fluid can be rigid, flexible or swelling. The reaction time of the injection resin can also be accelerated by means of catalysts. Since injection work can only be assessed on the outside of the construction, these activities require a great deal of experience and knowledge.
Constructive injection or gluing of parts is usually done with epoxy injection resin.
Unlike the sealing resins that are often based on polyurethane, the epoxy resins require a dry surface. Often in consultation with a constructor (who calculates the forces and values necessary for a thorough repair) an injection method and an injection resin are chosen. Depending on the crack width, a certain viscosity and strength can be selected.
After complete hardening, bonding has been achieved. The degree of filling and adhesion etc. can be determined afterwards by core drilling.