The encyclopedia · Engineering & Operations · Technical decision · 2010s–2024
Basilisk puts dormant bacteria in concrete that seal cracks from the inside
Bacterial spores in concrete wake when water seeps in and deposit limestone to close cracks, cutting costly repairs.
Basilisk · Heijmans · TU Delft
the move
Concrete is cheap until it cracks, then the repair bill climbs because you have to find the damage, reopen it and patch it before it lets more water in.
TU Delft researchers, later spun into Basilisk, added bacterial spores to the mix; water entering a crack reactivates the bacteria, which lay down limestone and seal the gap.
Contractor Heijmans used the self-healing concrete on real projects, including an underground pump-room wall and a ProRail railway structure, where cracks that opened as expected were closed by the bacteria rather than by hand.
why it works
- It fixes cracks before they become structural, when the repair is a fraction of the cost.
- The bacteria are dormant and cheap until water triggers them, so no active monitoring is needed.
- It extends service life, which lowers whole-life cost even if the upfront mix costs more.
- It works in the most common location — hidden microcracks — that nobody can reach to patch.
what transfers
Build the fix into the material so damage fixes itself while it is still cheap.
what came after
Basilisk's self-healing concrete moved from labs to live Dutch infrastructure (Heijmans for ProRail), and the approach is now cited as one of the more mature self-healing concrete technologies on the market.
references
- Application of bacteria as self-healing agent for the development of sustainable concrete
- Three concrete technologies to watch
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