6 ms·

Note that the construction took 45 years.

by yread 6y ago

Animats 6y ago
Those little intermediate piers were probably the slowest part of the on site work. And the most vulnerable part of the bridge, because that's what gets eroded. It's still the biggest cause of bridge failure.
- TeMPOraL 6y ago
  Makes me wonder if they've been done in parallel or serially. Also, I'd love to know how the bridge was designed. How did they figure out the shapes of the supporting structure, or location of the piers? Etc. We have this knowledge systematized today, but we use mathematics in a form that was developed much later than those bridges.
  - BerislavLopac 6y ago
    They had it systematized as well; the mason guilds were very thorough in protecting and maintaining knowledge throughout centuries.
  - spenczar5 6y ago
    According to JE Gordon in “ Structures: Or Why Things Don't Fall Down,” the answer is surprisingly simple: everything was massively, tremendously overbuilt. Also, often builders would start with scale models, and then exaggerate proportions - that doesn’t require sophisticated math. Just do the modeling “analog”!
    - azepoi 6y ago
      To see how overbuilt they are, you have to compare to late masonry stone arch bridges that are more 'airy'. Like so https://en.wikipedia.org/wiki/Paul_S%C3%A9journ%C3%A9#Gallery https://en.wikipedia.org/wiki/Paul_S%C3%A9journ%C3%A9#Galler... https://fr.wikipedia.org/wiki/Viaduc_de_la_Roizonne https://fr.wikipedia.org/wiki/Viaduc_de_la_Roizonne https://fr.wikipedia.org/wiki/Pont_des_Pierres#/media/Fichier:Pont_des_pierres_-_Montanges-3.jpg https://fr.wikipedia.org/wiki/Pont_des_Pierres#/media/Fichie...
  - Animats 6y ago
    Makes me wonder if they've been done in parallel or serially. Depends on the site, probably. Driving the first piles had to have been a tough job. Still, Caesar's legions did it to cross the Rhine in 55 BC. So pile-driving in water was being done a long time ago.
- Shivetya 6y ago
  This is what I was curious about, how long did the coffer dams take to erect and pump out and were they done separately or two or more at once? Still it seems that video makes it look far simpler that it truly was. Just the carting of the stone from quarry to the job site had to be an immense undertaking
galgalesh 6y ago
Isn't this longer than the average life expectancy of that time? I wonder what kind of incentives they had for such long-term projects.
- nosianu 6y ago
  The average was skewed by child and women (during/after birth) mortality. In lecture [0] the professor mentions as an aside: > And what is interesting, if you take out the childhood mortality, the Victorian person between 1850 and 1880 lived slightly longer, if he was a male, than you do today That's well after the middle ages, but still also well before modern medicine and technology, such as good sanitation and water systems. [0] https://www.gresham.ac.uk/lectures-and-events/return-of-the-microbes-how-infections-are-once-more-taking-over https://www.gresham.ac.uk/lectures-and-events/return-of-the-... (has the full text to search for the context of the quote)
  - jacquesm 6y ago
    Dental work is also a big driver in longevity, as is washing hands by doctors.
    - bhickey 6y ago
      Can you expand on this? Were abscesses killing people or something else?
      - jacquesm 6y ago
        https://www.mayoclinic.org/healthy-lifestyle/adult-health/in-depth/dental/art-20047475 https://www.mayoclinic.org/healthy-lifestyle/adult-health/in...
      - emiliobumachar 6y ago
        You know the very extreme of dental issues, nerve infections? Well, they're the very extreme because when it gets to the point of aching intensely all the time, anyone gets treated in a matter of days. If there's no treatment, it keeps moving in.
aequitas 6y ago
It's to bad the animation doesn't convey this information very well. Also all the manual labor and additional tools like boats involved. At the beginning the poles just fall out of thin air until they use some sort of pile driver to ram them in.
intrasight 6y ago
It was fast because they didn't have to go through an environmental review process ;)

Note that the construction took 45 years.

by yread 6y ago

Note that the construction took 45 years.

Those little intermediate piers were probably the slowest part of the on site work. And the most vulnerable part of the bridge, because that's what gets eroded. It's still the biggest cause of bridge failure.

TeMPOraL 6y ago
Makes me wonder if they've been done in parallel or serially. Also, I'd love to know how the bridge was designed. How did they figure out the shapes of the supporting structure, or location of the piers? Etc. We have this knowledge systematized today, but we use mathematics in a form that was developed much later than those bridges.
- BerislavLopac 6y ago
  They had it systematized as well; the mason guilds were very thorough in protecting and maintaining knowledge throughout centuries.
- spenczar5 6y ago
  According to JE Gordon in “ Structures: Or Why Things Don't Fall Down,” the answer is surprisingly simple: everything was massively, tremendously overbuilt. Also, often builders would start with scale models, and then exaggerate proportions - that doesn’t require sophisticated math. Just do the modeling “analog”!
  - azepoi 6y ago
    To see how overbuilt they are, you have to compare to late masonry stone arch bridges that are more 'airy'. Like so https://en.wikipedia.org/wiki/Paul_S%C3%A9journ%C3%A9#Gallery https://en.wikipedia.org/wiki/Paul_S%C3%A9journ%C3%A9#Galler... https://fr.wikipedia.org/wiki/Viaduc_de_la_Roizonne https://fr.wikipedia.org/wiki/Viaduc_de_la_Roizonne https://fr.wikipedia.org/wiki/Pont_des_Pierres#/media/Fichier:Pont_des_pierres_-_Montanges-3.jpg https://fr.wikipedia.org/wiki/Pont_des_Pierres#/media/Fichie...
- Animats 6y ago
  Makes me wonder if they've been done in parallel or serially. Depends on the site, probably. Driving the first piles had to have been a tough job. Still, Caesar's legions did it to cross the Rhine in 55 BC. So pile-driving in water was being done a long time ago.
Shivetya 6y ago
This is what I was curious about, how long did the coffer dams take to erect and pump out and were they done separately or two or more at once? Still it seems that video makes it look far simpler that it truly was. Just the carting of the stone from quarry to the job site had to be an immense undertaking

galgalesh 6y ago

Isn't this longer than the average life expectancy of that time? I wonder what kind of incentives they had for such long-term projects.

nosianu 6y ago
The average was skewed by child and women (during/after birth) mortality. In lecture [0] the professor mentions as an aside: > And what is interesting, if you take out the childhood mortality, the Victorian person between 1850 and 1880 lived slightly longer, if he was a male, than you do today That's well after the middle ages, but still also well before modern medicine and technology, such as good sanitation and water systems. [0] https://www.gresham.ac.uk/lectures-and-events/return-of-the-microbes-how-infections-are-once-more-taking-over https://www.gresham.ac.uk/lectures-and-events/return-of-the-... (has the full text to search for the context of the quote)
- jacquesm 6y ago
  Dental work is also a big driver in longevity, as is washing hands by doctors.
  - bhickey 6y ago
    Can you expand on this? Were abscesses killing people or something else?
    - jacquesm 6y ago
      https://www.mayoclinic.org/healthy-lifestyle/adult-health/in-depth/dental/art-20047475 https://www.mayoclinic.org/healthy-lifestyle/adult-health/in...
    - emiliobumachar 6y ago
      You know the very extreme of dental issues, nerve infections? Well, they're the very extreme because when it gets to the point of aching intensely all the time, anyone gets treated in a matter of days. If there's no treatment, it keeps moving in.

aequitas 6y ago

It's to bad the animation doesn't convey this information very well. Also all the manual labor and additional tools like boats involved. At the beginning the poles just fall out of thin air until they use some sort of pile driver to ram them in.

intrasight 6y ago

It was fast because they didn't have to go through an environmental review process ;)