Experimental investigation on bacterial concrete strength with Bacillus subtilis and crushed stone dust aggregate based on ultrasonic pulse velocity

The healing proportion of strengthening cracks in buildings such as Reinforced cement concrete (RCC) Houses, RCC Pipes, Canal Lining, Pavement etc. has been increased in the ongoing bacterial concrete. In order to fix the cracks in the concrete, it needs ordinary maintenance and exceptional treatment that can be terribly expensive. This is another method adopted by the use of microbiologically actuated calcite (CaCO3) precipitation in the arrangement of concrete. In this paper, an experimental study carried out using Bacillus subtilis bacteria and calcium lactate to heal the cracks in the concrete at different percentages such as 5%, 10% and 15% of cement weight for concrete grade M40. This paper presents the experimental results of the Ultrasonic Pulse Velocity (UPV) test carried out on Bacterial Concrete. From the Ultra sonic pulse velocity, dynamic modulus of elasticity and quality of concrete was determined at different ages. Relationships have been proposed between the strength of Bacterial concrete and UPV. Scanning Electronic Microscopy analysis carried out on convention and bacterial concrete. Finally the maximum strength attain at 10% bacterial replacement in concrete and Scanning electronic microscopy shows the calcium carbonate formation in concrete which is healing the cracks.