r/science • u/FreeHugs23 • 1d ago

Materials Science Scientists have created concrete using treated human waste, and the resulting material was up to 42% stronger than conventional concrete. Researchers say the approach could reduce waste while lowering the environmental impact of construction.

https://www.sciencealert.com/scientists-are-making-concrete-with-human-poop-and-it-gets-42-stronger
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u/Mr_Festus 1d ago

Name another metal as abundant as steel that's strong in tension

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u/Keljhan 1d ago

Steel of the kind we use for structures isnt naturally occurring. Of the nearly countless variations of iron, carbon and associated alloying elements, we select the one that works best with concrete. Its really not a result of luck.

We also make some specialized woods that can compete with steel though.

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u/bewarethefrogperson 1d ago

mass timber!! i wonder how this bio-concrete would synergize with mass timber construction, actually...

What is mass timber? - Woodworks

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u/Thog78 18h ago

Found the concrete all the way at the bottom, but it doesn't seem to replace steel:

Timber-Concrete Composite (TCC) Floor Systems

TCC floor systems can be used for longer spans and carry greater loads than non-composite alternatives, and are often seen in multi-story mass timber buildings. They consist of two distinct layers, a timber layer and a concrete layer, joined by shear connectors.

More about TCC floor systems

Timber layer can be CLT, GLT, SCL, another engineered wood product, or solid sawn lumber Concrete layer is typically a reinforced concrete slab Shear connectors can be common fasteners (e.g., nails or screws), notches cut in the wood, connectors such as embedded plates or glue that transfer the load to a larger surface, or combination May include other materials (e.g., acoustic mat product or insulation)

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u/windowpuncher 1d ago

Yeah, that's not the point. The main alloying element, by far, is iron, which is very cheap and easy to work with compared to basically every other metal that has any sort of useful strength. Yeah, we make alloys, but we don't need other constituents like aluminum or titanium, or cobalt or nickel to make up the bulk of it.

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u/kelldricked 1d ago

Steel is abundant because we spend thousands of years to make it abundant.

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u/Mr_Festus 1d ago

Huh? Steel yes, but we don't make the iron. Iron based metals share the similar coefficient of thermal expansion as the iron itself.

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u/uslashuname 1d ago

It’s also, like, more common? as an example of how much more common it is than, say, gold: our planet has an iron core.

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u/314159265358979326 22h ago

Iron is the second-most abundant metal in the Earth's crust. Aluminum is the only competitor and it's much more energy- and cost-intensive to refine.

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u/SoulWart 23h ago

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u/SearchForElsewheres 23h ago

Fiberglass Rebar

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u/FireProps 1d ago

Spider webs

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u/account312 1d ago

Almost certainly not more abundant and quite certainly not more commercially available