Which of the following concrete has ability to heal its crack?
- AHigh Performance Concrete
- BBacterial ConcreteCorrect
- CShotcrete
- DSelf-Compacting Concrete
Solution
Concept
Crack healing ability of bacterial concrete
Formula
NONE
Step-by-step solution
1. Bacterial concrete incorporates self-healing bacteria along with nutrients into the concrete matrix. 2. When cracks form and water enters, the bacteria become active and precipitate calcium carbonate to seal the cracks. 3. Therefore, bacterial concrete has the ability to self-heal cracks. Answer: B
Explanation
Bacterial concrete contains dormant bacteria and nutrients embedded within its matrix. When cracks form and water enters, the bacteria awaken and metabolize the nutrients to precipitate calcium carbonate, which fills and seals the cracks. This self-healing process restores the structural integrity and durability of the concrete.
Why the other options are wrong
A) High Performance Concrete is designed for high strength and durability, not self-healing. C) Shotcrete is concrete or mortar pneumatically projected at high velocity onto a surface. D) Self-Compacting Concrete is highly flowable concrete that settles without mechanical compaction.
Shortcut
Bacteria heal cracks: Bacterial concrete repairs itself.
Common mistake
Confusing bacterial concrete with self-compacting or high-performance concrete.
Correct answer: B) Bacterial Concrete