ADWAITH P V 
FASALU RAHMAN MANIMA 
ASWATHY KUNNUMMAL 
POOJA G 

Concrete remains the most widely used construction material across the world
due to its high compressive strength and versatility. However, it suffers from a
major drawback—its brittle nature and tendency to crack under stress, shrinkage,
and environmental effects. These cracks allow the ingress of water and chemicals,
leading to reduced durability and costly maintenance. In recent years, bacterial
concrete, also known as bio-concrete, has emerged as a sustainable alternative.
This material makes use of specific bacteria such as Bacillus subtilis, which can
survive in alkaline environments and precipitate calcium carbonate when
activated by moisture, thereby filling cracks and restoring structural integrity. The
present study focuses on a comparative investigation between conventional
concrete and bacterial concrete incorporating Bacillus subtilis. The primary

objectives include evaluating compressive, and flexural strength, assessing crack-
healing capability. Mix design, specimen preparation, and laboratory tests were

conducted to study the performance of both types of concrete under identical
conditions. The results from the experimental program demonstrate that bacterial
concrete exhibits superior mechanical and durability performance compared to
normal concrete. Enhanced compressive and flexural strength, reduced water
penetration, and visible self-healing of cracks were observed. These findings
establish bacterial concrete as a promising sustainable material with the potential
to reduce maintenance costs, extend service life, and address environmental
challenges in civil engineering construction.

Keywords: Bacterial Concrete, Self-Healing Concrete, Bacillus subtilis,
Sustainable Construction, Crack Healing, Compressive Strength, Flexural
Strength, Durability, Eco- Friendly Concrete