Concrete Repair: Remove the Cause Before Rebuilding the Surface
Spalling and exposed reinforcement are symptoms. Carbonation, chlorides, water ingress, poor cover or cracking may be driving deterioration.
New rust stains form at the edge of a previous repair.
Use the site evidence to agree a project-specific method with the responsible engineer, concrete producer, manufacturer or specialist applicator.
New rust stains form at the edge of a previous repair.
Investigate adjacent steel, chloride or carbonation extent, cover and moisture sources.
A small isolated patch may leave active corrosion beside it.
Extend condition assessment and design protection for the affected member or zone.
Treat reinforcement and repair boundaries under engineer-approved method; restore cover.
Monitor adjacent areas and record corrosion or moisture changes.
Do not repeat the same localized patch without reviewing the wider cause.
References inform the topic; they do not endorse a specific product for this project.