Researchers at the US Army Engineer Research and Development Center (ERDC) have developed a patent pending cement vitreous enamel coating for steel that is used to reinforce concrete (i.e. rebar, steel fibers, and metal plating). This porcelain coating more than triples the bond strength between concrete and steel, and prevents damaging steel corrosion.
The corrosion of embedded structural steel is the major cause for failure of reinforced concrete. As steel corrodes, the rust coating grows in thickness and puts the concrete in tension, cracking it around the steel and destroying any bonding of the steel to the concrete. The corrosion problem in reinforced concrete has defied attempts at solutions that are both technically sound and economically viable. Epoxy-coated rebar has been shown to lose its protective coating to debonding so rapidly that any benefit of protection is gone even before natural carbonating reactions and chloride diffusion have put the steel at risk for corrosion. Based on this performance, several state transportation departments have recommended that state agencies not use epoxy-coated reinforcement in concrete. Zinc-plated rebar delays the onset of corrosion, but does not stop it. Exotic materials such as stainless steel and fiber reinforced polymer reinforcement are presently too expensive, or carry a risk of sudden failure that prevents them from being widely adopted.
- Changes the fundamental chemistry at the concrete-to-steel interface by destroying the weak interface layer that normally forms at the steel surface
- Provides durable protection from corrosion even in aggressive chemical environments
- Issued US Patent 8,859,105 is available for license and commercialization
- Potential for cooperative research and development with ERDC inventors