Biologically Induced Self Healing Concrete: A Futuristic Solution for Crack Repair

Concrete is a mixture of cement, water, sand and other aggregates in adequate proportions. Its high tensile strength and ability to withstand a vast range of environmental changes makes it the first choice for construction material. One of the major problems associated with concrete is its permeability because penetration of gases and/or liquids from the surrounding environment into the concrete, followed by physical and/or chemical reactions within its internal structure/s leads to irreversible damages. Although cement has autonomous capacity to heal, however cracks <0.2mm width can only self-heal. Biomineralization is one of the best ecofriendly techniques to tackle the problem of cracks in concrete structures. Biologically induced self-healing is beneficial in addressing all the drawbacks of concrete matrix. The most promising technology for producing crack resistant/highly self healing concrete in near future seems to be “BacillaFilla”: genetically modified version of Bacillus subtilis, is a “custom –designed” bacteria to embed deep into the cracks in concrete where they produce a mix of calcium carbonate and a special bacteria glue that hardens to the same strength as of the surrounding concrete