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Yeah, the whole affair was about Barcelona getting a cut of the money from Sagrada Familia. > Barcelona officials said the city will be paid 4.6 million euros ($5.2 million) in fees under an agreement negotiated with a foundation devoted to completing and preserving La Sagrada Familia.
City: That's a nice, world-famous church you're building there. It would be a shame if something ... happened to it. Classic city government thug move.
The company I work for has actually been doing the engineering design work to finish the building. Pretty amazing how much was accomplished back in the day without computer aid. https://www.arup.com/projects/sagrada-familia
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Why are upside down strings an accurate model for compressed stone?
I'm not sure why , but in nature, any compressed stone arch's profile must fit within the profile of a hanging chain. This includes load bearing -- you can model the arch shape by adding weights to the chain. This is only really relevant to cases where the loads are higher than the weight of the arch/chain (manmade arches typically are just symmetrical as the loads are far less than the arch's). I'm sure someone here…
In a hanging chain, the sum of the forces pulling down (due to gravity/load) and away from the end (due to tension) on a given link must point in a direction exactly opposite the angle of the next chain link toward the end. Else that chain link would rotate until the above is true.
In a stone arch, the sum of the forces pushing down (due to gravity/load) and toward the base (due to compression) on a given stone must point in a direction exactly equal to the next stone toward the base. Else that stone would rotate and the arch would break.
The engineering work for Sagrada Familia was insanely clever. Gaudi build a scale model including accurate weights for the building materials, upside-down, out of strings and weights. That way he could design non-vertical pillars that branch like trees and where all the stresses were carried by compression through the stonework. It is really a marvel of pre-computer technical design! [1] https://memetician.livejourna…
Why are upside down strings an accurate model for compressed stone?
There are plenty of ways this can go wrong. The little weights Gaudí used might not correctly model the weight of the stone. The whole thing might be unstable under inevitable sideways forces from wind and such, although one could blow on the string model to make sure it doesn’t start swinging to approximate this. And the string model probably doesn’t say much about the distribution of compression loads in the stone, especially if the overall structure is not statically determinate.
The engineering work for Sagrada Familia was insanely clever. Gaudi build a scale model including accurate weights for the building materials, upside-down, out of strings and weights. That way he could design non-vertical pillars that branch like trees and where all the stresses were carried by compression through the stonework. It is really a marvel of pre-computer technical design! [1] https://memetician.livejourna…
Why are upside down strings an accurate model for compressed stone?
The engineering work for Sagrada Familia was insanely clever. Gaudi build a scale model including accurate weights for the building materials, upside-down, out of strings and weights. That way he could design non-vertical pillars that branch like trees and where all the stresses were carried by compression through the stonework. It is really a marvel of pre-computer technical design! [1] https://memetician.livejourna…
Earlier quoted context omitted.
I'm not sure why , but in nature, any compressed stone arch's profile must fit within the profile of a hanging chain. This includes load bearing -- you can model the arch shape by adding weights to the chain. This is only really relevant to cases where the loads are higher than the weight of the arch/chain (manmade arches typically are just symmetrical as the loads are far less than the arch's). I'm sure someone here…
That's an interesting factoid I've never thought about before. Here's my guess why it's true. In a hanging chain, the sum of the forces pulling down (due to gravity/load) and away from the end (due to tension) on a given link must point in a direction exactly opposite the angle of the next chain link toward the end. Else that chain link would rotate until the above is true. In a stone arch, the sum of the forces push…
Yeah, the whole affair was about Barcelona getting a cut of the money from Sagrada Familia. > Barcelona officials said the city will be paid 4.6 million euros ($5.2 million) in fees under an agreement negotiated with a foundation devoted to completing and preserving La Sagrada Familia.
However, the Sagrada Familia is already a massive benefit for the city due to the visitors it attracts. Its administrators could've just raised the middle finger and Barcelona would definitely not have tore it down nor stopped its construction.
Why did they enter the agreement then? The Sagrada Familia's original plans include a number of gardens that span outside of its current land. With this agreement in place, now the city can officially start making plans to eventually evict residents in the affected land space, freeing it up for the monument's gardens.
Earlier quoted context omitted.
Why are upside down strings an accurate model for compressed stone?
To an excellent approximation, a structure made entirely of string and weights has tension on the strings but no shear stress on the string. (This is because string is floppy — if you pull gently on a string, you’ll pull the other end toward you but not sideways.). If the whole structure dangles without moving, that means that all the forces (tension and gravity) balance everywhere. If you flip the sign of all forces…
Imagine a single weight dangling from two strings of roughly equal lengths attached near other on the ceiling. The weight will swing if you blow on it. If you turn the strings into (lightweight) compression elements and turn the whole thing upside down, it will be a bipod. The weight will indeed be balanced, but any slight perturbation will knock it over or will at least require shear forces to avoid this fate.
Now try this with three strings. The weight will resist swinging if you blow on it, and the cathedralized version is a stable tripod.
Now try four strings. If the string model is imperfect, one string might be slack. If you cathedralize it, you get a quadropod, and, if the construction is at all imperfect, the loads on the four legs might be wildly different and, if it’s too far off, the structure might wobble. This structure is statically indeterminate.
There is, strictly speaking, nothing strictly wrong with static indeterminacy, but it makes the analysis considerably more complicated.
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In order to really capture the beauty of the interior, you have to pick the right angle and then force your camera to accentuate color. The interior is magical in a way that can be hard for a point-and-shoot to capture without fiddling. Of course, the internet being what it is, a google image search for "sagrada familia interior" brings up a few great examples like https://cdn.barcelonalowdown.com/barcelona-lowdown/u…
Absolutely. Add to that the fact that the inside looks different at different times of the day due to which windows accentuate the inside.