How a 14th-century bridge in Prague was built

I feel like the Clock competes with it.

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Do you know if they they are relying on cement that cures under water?

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Yeah, nah

Https://wiki.c2.com/?MedievalArchitecture

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Even those that collapsed had beautiful precision stonework, though. It’s just that the overall effect wasn’t achieved.

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Whether you mean “they” of the 14th century or “they” of now, I honestly don’t know. I should think the only difference is when you re-flood the coffer dams though. Before or after the mortar on the masonry (or concrete in modern case) is cured.

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That’s actually a difficult question to answer. The middle ages did not know artificially hydraulic lime mortars of the type the Romans used and that set underwater. Those are lime mortars with added clay minerals. Medieval mortars generally set in the air, which means they would need to be kept dry* for days or weeks. However, it is possible the middle ages used naturally hydraulic mortars for hydraulic engineering applications like this, i.e. mortar from limes with natural impurities that mimic the intentional additives. Either way, however, lime mortar actually needs centuries to properly cure all the way through but that process happens on a chemical level and is, AFAIK, independent of outside moisture. So this is just a question of whether they had to keep the cofferdam up for a few weeks longer and thus ultimately moot.

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* Actually it had to be kept ■■■■■ but protected from the weather nonetheless

Edit: fucks sake, this was a legitimate use of the word ■■■■■! “Damp”, let’s go with “damp”.

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As medievalist potboilers go, it’s more Pillars of the Earth, which actually has the similar construction of a stone bridge as one of the driving plot elements.

In that book the heroic mason person is like “why don’t we simply build the piers inside coffers” and everyone’s all “wow so easy” but I remember thinking that (as this video suggests) building the coffers would probably be quite a bit more of a feat than the piers themselves.

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From the commentary: “The rough bock is moved into the mason’s lodge…”

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I guess all that filler was large-aggregate concrete? Would like to have seen the mixing and pouring of that process. Really enjoyed this find, thanks Rob!

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caitlin-doughty-■■■■■

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Rubble bound with lime poured over it, most likely.

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I was really only thinking of the opening credits, where CG structures are created out of nothing. I guess that didn’t come across in my original comment.

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I forgot they made it into a TV show (on purpose, after the last coupla seasons)

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I’m sure the ferryman’s guild was none too pleased about this.

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By the way, the term for the framing that is build under a bridge to support it during construction (but later removed) is called a “falsework.”

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