Bio-Concrete: A Step Towards Revolutionising The Construction Business?
Concrete is a widely produced and used material for the construction of buildings and infrastructure. It is prepared by mixing aggregates consisting of large chunks of rock, sand or gravel along with Portland cement. However, low tensile strength and formation of cracks are the most common and biggest disadvantages of concrete structures. The cracks could lead to water leakage through walls and ceilings, ultimately reaching upto and corroding the steel reinforcements, causing the structure to collapse. Fixing concrete is expensive too.
With the emergence of state-of-the-art concrete technology, the quality and type of concretes employed, have undergone a transformation. In a breakthrough achievement, scientists have developed a bio-concrete which is produced using normal concrete, mixed with special limestone-producing bacteria. The new concrete is believed to heal itself when cracks develop.
MakaaniQ brings you more details on this technological advancement that could be a turning point in the field of construction.
Benefits of bio-concrete
Sustainability: Production of concrete contributes to nearly five per cent of CO2 emissions causing global warming. Bio-concrete promotes sustainability by aiding in the filtration of rainwater, by maintaining the pH levels within the ideal range and softening the rainwater. Bio- concrete is a sustainable solution that could prolong the lifespan of existing structures.
Strength: As compared to conventional concrete, the bio-concrete is durable, possesses lower permeability and offers better resistance to corrosion.
Low cost: Since the bio-concrete structure possesses self-healing abilities, the material will ensure reduction in the long-term maintenance costs of the building.
Possible usages in the Indian scenario: It is ideal for repairing underground structures in dams, basements or structures meant for irrigation, as moisture is the only requirement for its functioning. Most Indian cities like New Delhi, Lucknow, Patna, etc., are prone to drastic temperature changes, which could severely deteriorate concrete surfaces. Bio-concrete can, thus, serve as an alternative construction material.
The process of making bio-concrete
Bacillus bacteria is added during the production of concrete, along with the mixture of cement, sand and water. The bacteria feeds on pellets of calcium lactate, which are water soluble. When the structure develops a crack, and comes in contact with moisture, the pellets open up and allow the bacteria to feed, germinate and multiply, thus, forming limestone that fills up the cracks. If the concrete remains intact and sealed, not allowing water to seep in, the bacteria would remain inactive.
Presently, the technology is at a nascent stage and is useful to mend cracks with dimensions of 0.8mm width. There is still a long way to go for bio-concrete to completely replace existing materials and be used as an alternative green construction resource.