Studies on Strength Charecterstics of Bacillus Subtilus Induced Self Healing Bacterial Concrete.

Abstract

In spite of many precautions cracks in concrete are inevitable, cracks may be due to many reasons. Microbiologically induced calcite precipitation (MICP) has been shown to prolong concrete service life due to calcium carbonate precipitation. The calcium carbonate heals the concrete by solidifying on the cracked concrete surface mimicking the process by which bone fractures in human body are healed by osteoblast cells that mineralize to reform the bone. Two methods are currently being studied: injection of calcium carbonate precipitating bacteria and by applying bacteria and nutrients as a surface treatment. In the present study attempt is made to fill the cracks with the help of bacteria which has a self-healing property. The potential bacteria ‘bacillus subtilus’ is isolated and cultured. The optimum parameter will be considered and the bacterial liquid of 105 per ml of water of concentration is being coated on cracked surface of concrete and the variation in the strength characteristics was studied. Calcite formation of isolated bacteria which can produce calcite precipitates on suitable media supplemented with a calcium source. It is observed that there is an increase of 12.83% in compressive strength of bacterial concrete when compared with controlled concrete