Bio-induction and bioremediation of cementitious composites using microbial mineral precipitation - A review

- Paper reviews the process of microbially induced calcite precipitation (MICP) in cementitious composites.
- Parameters affecting the process of MICP are elucidated.
- Methods employed by researchers for improving strength, durability, and crack remediation are reviewed.
- Tests employed for the assessment of the success of MICP are thoroughly investigated.
- Scope of research for closing the gaps between research and practice for different applications are identified.

Cementitious composites are widely used in the construction industry around the globe. Nevertheless, these are prone to cracking because of their low tensile strength. The reinforcement provided to carry tensile stresses gets exposed to the outside environment due to cracking thereby reducing the service life of structures. The control of crack widths in concrete is thus necessary to ensure durability. Research studies have shown that bacteria exist that are able to precipitate calcite, and may thus heal cracks thereby improving the durability of concrete. This technique is highly desirable because the microbially induced calcite precipitation (MICP) is pollution-free and natural. This novel technique may also be used in protecting historical stone monuments without affecting their appearance. This article reviews the process of bioremediation of cementitious composites employed for improving their properties. Different parameters affecting the process of MICP such as the bacterial genotypes, biotic, and abiotic factors are elucidated. Methods employed by various researchers for improving strength, durability, and crack remediation are reviewed. The tests employed for the assessment of the success of MICP are thoroughly investigated. This paper presents an exhaustive review by covering most of the studies available in published literature till date. The scope of research for closing the gaps between research and practice for different fields of applications have been identified. In the end, a summary of the research status of bio-induction and bioremediation of cementitious composites is given which highlights its great potential and need for further research.