Bacterial concrete-a sustainable solution for concrete maintenance

Abstract

Cracks formed in concrete are inescapable and are one of the major reasons for the weaknesses of concrete. Majorly water along with other components penetrate through these cracks resulting in corrosion thereby reducing the strength of concrete directly hampering its life. The objective of present research work is to promote sustainable development and to identify sustainable materials for treating cracks formed in concrete. Various researches have shown positive results by adding calcite precipitating bacteria in concrete, also known as bacterial concrete or self-healing concrete. This research is dedicated to check the suitability of mixing these self-healing calcite depositing bacteria with concrete in order to increase the compressive strength of concrete, reduce its permeability and seepage of water by bio-mineralization process. Substantial increase in strength is observed in concrete specimens when casted with bacterial solution. The study has devised methods or ways to test the effect of use of bacteria in concrete. Tests on concrete slab with various combinations of bacterial solution as well as varied percentage of bacterial solution have been conducted. Use of bacterial solution for surface application on slab to test the sealing capacity is done. Results have been compared with conventional concrete. Biological modifications of construction materials are the need of the hour for strength improvement and long term sustainability. The present study proposes a promising sustainable repair method for concrete.