ENRICHMENT IN DURABILITY OF CONCRETE BY INSERTION OF BACILLIOUS PESTURI BACTERIA

Microbial concrete presents a potentially enormous lengthening in service-life of the infrastructure, substantially reduces the maintenance costs and also considerably increases the safety of structures. This unique way of concrete design crossbreed between biology and engineering study of concrete is called microbial concrete, which involves the utilization of bacteria to increase the strength and durability of concrete. These microorganisms are used for calcium carbonate precipitation in concrete, it is highly desirable because the calcite precipitation induced as a result of microbial activities is pollution free and natural.The approach does not deplete any natural resources since the bacteria used can be easily reproduced by cultivation process. The use of a biological approach in concrete is also considered as a green technology as its production does not involve greenhouse gas emission. Therefore, bacterial induced Calcium Carbonate (Calcite) precipitation has been proposed as an alternative and environmentally friendly way for improvement of strength and durability of concrete. Different proportions of 105, 106, 107, 108 and 109 cells/ml concentration was added in concrete and durability was tested by NaCl water (5% by weight). Results indicates improvement in durability of concrete after inclusion of bacteria. And this can be a very significant change in the durability related properties of concrete.