Corroded reinforcement is the chief cause of concrete deterioration, which prompts subsequent repairs. For repairs to be sound, contractors must ensure adequate adhesion of new patch repair materials by proper preparation of exposed reinforcing steel.
ICRI’s 310.1R-2008 “Guide for Surface Preparation for Repair of Resulting from Reinforcing Steel Corrosion” states that exposed reinforcing steel should be free of any materials such as concrete, dirt, and corrosion products that could interfere with repair material adhesion, although a tightly bonded light rust on the rebar surface is usually not detrimental to the bond of patch materials. When it comes to tackling reinforcement surface prep and ongoing protection, CorrVerter® MCI® Rust Primer provides clear performance and application advantages to mitigate rebar corrosion.
Resolving Existing Corrosion
Competitor rebar coatings containing corrosion inhibitor typically require a rust-free application surface to work properly. Abrasive or water blasting and intensive labor are usually needed to ensure corroded surfaces are completely clean. This is not necessary for CorrVerter MCI, which is recommended for application to rusty or poorly prepared steel surfaces where further corrosion protection is required and good surface preparation is difficult to achieve. CorrVerter MCI is a unique formulation of chelating agents combined with a high-solids waterborne latex with extremely low water vapor permeability. This fast drying, single-component primer converts surface rust into a hydrophobic passive layer and offers excellent protection against re-rusting of metal surfaces. Reinforcement coated with CorrVerter MCI Rust Primer has similar bond strength to concrete compared with uncoated rebar.
Preventing Future Corrosion
While competitor bonding agents list rebar corrosion protection as one of their benefits but actual performance is vague or reduced compared to CorrVerter MCI. CorrVerter MCI Rust Primer data report 500 hours of corrosion resistance in salt spray testing (ASTM B-117) at only 3-5 mils (75-125 µm) DFT (applied at 8.7-14.5 mils [217.5-362.5 µm] WFT).
CorrVerter MCI Primer offers engineers, owners, contractors, DOTs and government agencies a convenient, low-labor option when performing repairs on heavily corroded rebar and other metal surfaces. It converts rust quickly and provides ongoing protection without compromising bond strength. Contractors can rely on it as an integral part of a high-performance repair system that extends the service life of concrete structures.