Abstract
Crack formation is a very common phenomenon in concrete structures which allows the water and chemicals through the cracks and decreases the durability and strength. For repairing the cracks developed in the concrete, it requires maintenance and special type of treatment. So, to overcome this problem an autonomous self healing mechanism is introduced into the concrete which helps to repair the cracks with the help of Bacillus bacteria by producing calcium carbonate crystals which seals the micro cracks and pores in the concrete. For the isolation of bacteria nearly eighty soil samples were collected from soils of extreme environments and cultured in three different media. A total of two thousand seventy colonies were observed and fifty five Bacillus colonies were isolated and identified by Gram staining and different biochemical tests.
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