In the biological process of self-healing concrete bacteria produce crystals of calcium carbonate, which fills the cracks on the surface of the concrete. Usually this type of bacteria feed theirselves with calcium lactate and during metabolism process calcium carbonate is formed, which ends in the cracks. Inactive bacteria become active when they get in contact with water and oxygen. During metabolism bacteria consume oxygen, and as a result that contributes to a lower amount of oxygen in the concrete and better corrosion resistance of reinforced concrete. Because of this kind of biological conversion of chemical substances and consequently lack of oxygen in the concrete, durability and resistance of concrete structures is improved.
The purpose of graduation thesis was examination of accessible literature from the field of biological processes of self-healing concretes and comparison of those with natural processes of self-healing concretes. Knowledge and research conclusions of different authors, which describes processes and effects of self-healing concrete, are still different from many aspects. Authors still aren't unified, which type of bacteria is the most appropriate for usage in self-healing concrete, which organic nourishment or nutrient is most effective and what technology of making self-healing concrete is most adequate from different perspectives in civil engineering.
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