Flexural Strength Behaviour of Microbial Blended Concrete Beams: Fid-Bau Portal

Flexural Strength Behaviour of Microbial Blended Concrete Beams

Venkata Sai Nagendra, C. / Jayaramappa, N.

One of the biggest issues facing the building sector is concrete cracks. Usually, some sort of human involvement is used to fix any fissures, and especially in concrete structures, cracks require expensive and even unattainable human maintenance at regular intervals. The inclusion of bacteria may be a very beneficial solution to this issue, as it can reduce maintenance requirements and improve concrete’s longevity. Bacillus subtilis bacteria have the ability to produce calcium carbonate crystals through metabolic processes. When incorporated into concrete mixtures, these bacteria can promote the formation of calcium carbonate, which fills in fissures and pores within the concrete matrix, enhancing its strength and durability. This investigation experimentally deals with the flexural strength characteristics of blended concrete beams made of partial replacement of cement by GGBS and Metakaolin at an amount of 10% each (optimum percentage obtained by using different percentages of both admixtures) and compared with blended concrete beams incorporated with Bacillus subtilis bacterium. The capacity of load-carrying and deflection criteria of conventional beams were found and compared with those of blended concrete beams and beams incorporated with bacteria. In addition to this, the research also focused on the self-healing capacity of Microbial concrete beams which are kept under conventional (water) curing and saturated soil exposure after flexural strength test, was determined by evaluating the crack width healing using an ultrasonic pulse velocity test. The test results show that bacterially blended concrete beams attained higher load-carrying capacity as well as greater healing of cracks when compared to other beams.