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Biologists Create Self-Healing Concrete
Mr.Intel writes: A team of microbiologists from the Delft University of Technology claims to have invented "bioconcrete" — concrete that heals cracks and breaks using bacteria. The goal was to find a type of bacteria that could live inside concrete and also produce small amount of limestone that could re-seal cracks. This is a difficult prospect because concrete is quite dry and strongly alkaline. The bacteria needed to be able to stay alive for years in those conditions before being activated by water. The bacteria also need a food source — simply adding sugar to concrete will make it weak. The scientists used calcium lactate instead, adding biodegradable capsules of it to the concrete mix. "When cracks eventually begin to form in the concrete, water enters and open the capsules. The bacteria then germinate, multiply and feed on the lactate, and in doing so they combine the calcium with carbonate ions to form calcite, or limestone, which closes up the cracks."
I'm all for it, as long as nothing could possibly go wrong!
>The goal was to find a type of bacteria that could live inside concrete
If you can call that "living." Think of the bacteria!
Bacterial concrete is ideal for constructing underground retainers for hazardous waste, as no humans would have to go near it to repair any occurring cracks. For residential buildings, however, it does seem the traditional repairing of cracks will remain the most economically attractive solution for now.
Currently, our research focuses on creating the right conditions for the bacteria to produce as much calcite as possible and on optimizing the distribution of food for the bacteria.
"First they came for the slanderers and i said nothing."
wonder if coral has ever been considered.
I here the contractor now. I thought you told me you dug up the road yesterday? Yes I did, honest. I don't know, someone mush have put it back there.
We already have a plethora of contractors, engineers and manufacturers intent on bypassing the critical stoichiometry required to produce defect free, indestructible concrete. Of course, this is all caused by cost. Which means, due to greed and stupidity, people will accept inferior products if it is cheaper. Even dirt. Most people will tell you that ALL concrete will eventually develop cracks. They are incompetant morons.
Not sure if anyone is working on 3d printing concrete, I just assume someone is because it is a natural application. If you can't produce crack free concrete, there is something wrong with you.
One of the challenges faced by building subterranean homes is the threat of water damage over time as the home settles. Typical solutions include lining the outside of the shell, french drains, and/or reinforced plasticized concrete. Even when thinking more inside the box with traditional building, there are significant benefits to things like healing cracked slabs or preventing basement water damage.
It seems to me that this type of technology could be used on pre-existing concrete as well. Assuming it is strong enough, and it seems to be, it could be injected into foundation cracks. The crack would be fixed from the inside out. The savings in time and money would be enormous and it would be vastly superior to current methods of foundation repair.
heal thyself!
Is this a theoretical development or does it have concrete uses?
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
It will have to repair fast enough to beat the dirt and weeds from staking a claim to those cracks.
As a trade representative from Janus VI, my Horta constituents are very interested!
Why not just make self healing limestone instead?
Vivat Antifragility !
Anyone watch "game of thrones"? this is exactly how things like grey scale start...next thing we know...people will be turning to concrete, and dragons will be flying around.
How does it keep from activating when the concrete is initially wet from mixing?
Vegans aren't unwilling to do anything that could feasibly kill animals, they're unwilling to eat animal products. Gut bacteria are not animals and probably don't suffer (or even think for that matter). I'm not a vegan myself, but I'd imagine they're trying to minimize their contribution to suffering and don't pretend to eliminate it entirely.
You strike me as someone who says "atheists don't believe in anything" and "vaccine supporters think the government owns you".
Isn't limestone relatively easy washed out by water? (Which is major cave building mechanism)
What keeps the surface of the concrete from "growing"?
Cementinator
Table-ized A.I.
Some of you may have reservations about the use of live concrete. Don't worry, just give it some time. It will grow on you.
If the concrete fills it's own cracks automagically, two questions spring to mind: 1) Will the crack-filling material have the same load bearing properties or (as I suspect) it will be much weaker at those spots, and 2) will the filled cracks disguise the facts that the object may be under a load that was not anticipated by the designer (tensile or bending loads vs. compressive loads)?
Reinforced concrete is often used in bending and tensile load applications in architecture, and if the reinforcing is not stiff enough cracks often will appear on the surface. They are unsightly, but if the reinforcing is taking the load (as it should) these are not structural deficiencies. But for complex architectural domes and shells, the presence and size of these cracks is something that needs to be monitored.
If the concrete is used in a container and it cracks, we may actually want to see the crack as that is a warning that something is being loaded in an unanticipated way. Hiding it with a self-filling mechanism may not be desirable.
Left MS Windows for Linux Mint and never looked back!
Vote for Bernie in 2016!
You can now stop calling futuristic concrete 'enzyme bonded concrete'.
Thank you,
Reader
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In a previous life I worked designing concrete mixes for a decade or so. I see problems when the bacteria start producing lime unexpectedly. Cracks? We got 'em.
To ensure perfect aim, shoot first and call whatever you hit the target
it sounds like an upgrade avaliable in starcraft...
This self-healing concrete only heals its crack, but when small of concrete breaks apart from the parent it wont be able to make itself to original shape
Seriously, nobody remembers BSG Galactica Cylon based bio crack fixer?
I doubt this place is for geeks anymore.
It depends upon formulation but calcium migrates in concrete and can fill thin cracks due to chemical action. No bacteria required. Some formulations do this more than others. Look for old concrete back when energy use was less of a concern and you can see the self healing cracks. it doesn't work where the concrete is in motion and I suspect this bio process will not either. Journalism is less than perfect so I suspect the researchers are trying to provide the self healing properties of concrete to the fly ash and other amendment based concrete formulations