But 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. Epoxy injection is commonly used to restore the pre-cracking condition of the member without increasing its strength.
The epoxy tensile bond to the concrete substrate is stronger than the tensile strength of concrete. Future cracking may occur with the same load as that of the original seamless member, but at different locations. Reinforcement is achieved by installing additional reinforcements along the fault plane in combination with resin injection. Often, internal or external reinforcement is installed in combination with epoxy injection for strengthening and restoration.
Crack injection can be successfully performed in cracks as narrow as 0.013 mm wide with general epoxy injection resins. Cracks with less width can be injected with epoxy or other polymer systems having a low viscosity of 200 cps. Epoxy resins have relatively high tensile and compressive strengths relative to concrete. They are generally considered “rigid” materials and are widely used for structural repairs by injecting cracks and voids into load-bearing reinforced concrete structures or elements.
Its low viscosity allows excellent penetration into cracks and strong adhesion to concrete, which helps to ensure permanent and long-lasting load transfer. Epoxy resin based materials are suitable for many different structural injection requirements and applications in dry to slightly humid conditions. The ARDEX injection range for concrete crack repair %26 uses a high-strength, fast-setting two-part system to repair concrete damage from fine cracks to structural repairs. These products are ideal for repairing holes, chips and cracks in concrete, in both internal and external situations where heavy vehicle traffic is anticipated.
Once cured, the repaired concrete cracks will be two to three times stronger than the original concrete, ensuring a durable and long-lasting crack repair solution. Crack injection of structural concrete with super low viscosity epoxy. Epoxy pressure injection can be used to bond cracks that have an opening greater than or equal to 0.05 mm. Epoxy resins and other resins lose strength when exposed to fire or sustained elevated temperatures and flame retardant protection is required for such structural repairs.
Epoxy resins are excellent for recovering structural strength in torn concrete structures and other substrates such as wood. Epoxy resins that are labeled as water insensitive during curing can develop milky white bond lines if injected into wet or damp cracks. For the repair of cracks in concrete floors, there are certain epoxy and polyurea materials, suitable for such tile repairs. Epoxy resins are formulated with specific fillers to allow the penetration of small cracks and a low exotherm for larger cracks.