What is the role of bacteria in bio-concrete?
- ATo reduce setting time
- BTo improve compressive strength
- CTo produce calcium carbonate for self-healing cracksCorrect
- DTo increase workability
Solution
Concept
Self-healing concrete
Step-by-step solution
1. Bacteria (e.g. Bacillus) in the mix produce calcite when water enters a crack. 2. This seals the cracks.
Explanation
Bacterial metabolism produces calcium carbonate, healing cracks.
Why the other options are wrong
The bacteria do not change setting, strength or workability.
Shortcut
Bacteria → CaCO₃ → crack healing.
Correct answer: C) To produce calcium carbonate for self-healing cracks