Definition
Bonded repair is a concrete repair method where the new repair material is designed to adhere directly to the existing concrete substrate, allowing both materials to act together as a single structural or protective system.
Explanation
This approach is commonly used in patch repairs, reinstatement works, overlays, and structural strengthening where load transfer and continuity between old and new concrete are essential. The success of a bonded repair depends heavily on proper surface preparation, including breakout to sound concrete, roughening, cleaning, and removal of contamination.
Repair mortars, polymer-modified systems, epoxy-bonded materials, and spray-applied concrete may all be used as bonded repair systems depending on the application. Bond strength must be sufficient to resist shrinkage stresses, loading, and environmental exposure without debonding.
Bonded repair is often preferred where maintaining original dimensions is important or where localised structural reinstatement is required without full recasting.
Why It Matters
Poor bond is a common cause of premature repair failure. A properly designed bonded repair ensures durability, structural performance, and long-term protection against moisture ingress and reinforcement corrosion.