Epoxy injection is a cost-effective method for repairing immobile cracks in walls, slabs, columns, and concrete pillars. It can restore concrete to its pre-cracked strength. Before any injection, it is essential to identify the cause of the crack. Pressure epoxy injection can be used to bond cracks that have an opening of 0.05 mm or more.
This method is not suitable if the crack is active, there are numerous cracks, or water leakage cannot be controlled. If the cause of the cracking has not been addressed, it will reoccur near the original crack. Great care must be taken when injecting cracks that are not visible on all surfaces. Epoxy injections are designed and used to restore the strength and integrity of structural elements in cracked concrete.
However, these cracks must be relatively dry for the epoxy to achieve adhesion. After all, epoxy injections will not shift or react with water. Therefore, they are ineffective in waterproofing a leaky crack. Resin injection is based on repairing cracked or delaminated concrete and for sealing cracks in concrete to prevent water leakage.
Two basic types of resins and injection techniques are used to repair concrete; epoxy resins and polyurethane resins. Epoxy resins cure to form solids with a high strength and a relatively high modulus of elasticity. Connect the mouthpiece to the second tea port and begin the injection until the surgical tube expands and fills. The epoxy injection method is an easy way to repair cracks in a structure and works great for horizontal, vertical, and overhead applications. The type of injection resin you will need varies depending on the depth of the structural cracks, as well as whether or not it is a crack on the blind side. The epoxy injection process begins with the application of a coating paste, which serves to seal the surface of the crack and help bond the injection ports to the concrete.
There are some methods that inspectors can use to verify that the epoxy injection process has been effective and is sufficient to repair structural damage. Verification that the epoxy is completely insensitive to water should be done by injecting test epoxy into pre-moistened cracks, then evaluating the core sample of cured epoxy injected into the crack. Consequently, epoxy injection means applying an adhesive material (epoxy resin) to a concrete body under pressure to repair its crack. Epoxy resins labeled as water insensitive during curing can develop milky white bond lines if injected into wet or damp cracks. Once capping paste is used, ports are drilled or installed, and any loose materials and dust are removed from cracks, epoxy injection can begin. This observation window can be used as viewpoints during injection process to examine flow of epoxy resin through crack.
All injection products have disadvantage of being somewhat unpredictable, because both hole drilling and material injection are done blindly. At same time, leave gap of 25-50 mm at distance interval of approximately 200-250 mm for epoxy injection installation system according to general rule of same. Epoxy and other resins lose strength when exposed to fire or sustained elevated temperatures and flame retardant protection is required for such structural repairs. Typically, epoxy injection system contains kit that has two chemicals and uses those two chemicals by mixing them thoroughly according to company specifications.