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Just learned that Roman concrete used volcanic ash and actually gets stronger over time
I was reading a paper from Berkeley about their work on Roman concrete and found out that the seawater reacting with the volcanic ash creates new minerals that reinforce the structure. They call it a hot lime mix. The stuff in the breakwaters at Portus Cosanus has been sitting there for over 2,000 years and is still setting. Has anyone seen a modern concrete mix that actually tries to copy that?
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wrenh651mo ago
The "still setting" part is what gets me. People talk about modern concrete like it's permanent but it's not. Roman concrete actually improves with cracks and exposure. We've got buildings falling apart after 50 years because our stuff relies on steel rebar that rusts and blows the concrete apart from the inside. You beat the rebar problem you beat modern concrete's biggest weakness. Nobody's cracked it yet because the volcanic pozzolan supply chains don't exist anymore and mixing it right is a lost art.
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james_singh71mo ago
Ever tried mixing in a little rice husk ash with the lime? I've seen people get surprisingly close to that Roman chemistry with it, and it's way easier to source than volcanic rock. The trick is getting the particle size right, too fine and it turns to mud instead of binding.
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jessicac2813d ago
Didn't the Romans also have a slavery problem though?
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