In concrete construction one of the major worries is cracking in concrete. The single most cause for cracks in concrete is erosion of reinforcement. Rebar is the weakest link to any concrete system. All too often designers and builders forget that concrete is porous throughout its life cycle.
When originally poured, concrete is alkaline thus offering a natural protection in the reinforcement. Over time through oxidation and chlorine deposits, concrete will become acidic. This creates a galvanic reaction in the rebar. Consequentially, the rebar rusts and expands thus causing the cracking.
Common methods to mitigate this process are using epoxy, zinc coated or galvanized rebar, and/or coating the surface with a membrane or sealer. These are all short-term solutions.
By far the best way to address this problem is to electrify the rebar. This will prevent galvanization from occurring in the first place. All things remaining static, the life cycle of will increase concrete almost indefinitely.
Here is a short video of repairing cracks in concrete.
Video Courtesy : www.concretemender.com
