6 ms·

The construction of the buildings, you know, jigsaw pieces of rock, made perfect sense when I flashed on it the other day. I've lived in the Andes. The worst

The construction of the buildings, you know, jigsaw pieces of rock, made perfect sense when I flashed on it the other day. I've lived in the Andes. The worst earthquakes. A building made of tesselated bricks would not survive, whereas a building made of jigsaw rocks held together by gravity will allow the earthquake to lift its rocks, but they will fall into place in the exact same way they were when the earthquake's over.

kibwen 5y ago
Words don't quite do their stonework justice. Plenty of old-world architecture is made of whatever weirdly-shaped rocks they had lying around, but they use mortar to hold them together. The Incan mortar-less stone puzzle look is extremely cool: https://commons.wikimedia.org/wiki/File:Mur_Inca_D%C3%A9cembre_2007.jpg https://commons.wikimedia.org/wiki/File:Mur_Inca_D%C3%A9cemb... "Usually the walls of Incan buildings were slightly inclined inside and the corners were rounded. This, in combination with masonry thoroughness, led Incan buildings to have a peerless seismic resistance thanks to high static and dynamic steadiness, absence of resonant frequencies and stress concentration points. During an earthquake with a small or moderate magnitude, masonry was stable, and during a strong earthquake stone blocks were “ dancing ” near their normal positions and lay down exactly in right order after an earthquake."
- knolax 5y ago
  Don't stone walls in Europe use the same technique?
  - robinsoh 5y ago
    Not to my knowledge. Almost all European stone walls all use mortar. Drystan is more like piling rocks together. They aren't shaped. The Inca (or possibly their predecessor civilization) techniques at Sacsayhuaman and Machu Picchu are far more advanced. It is still unclear exactly how they achieved those structures. We're talking about 140 tonne rocks being put together to form those structures and assembled without mortar in such a way that one can't slip a piece of paper in between rocks. When the Conquistadors encountered the structures, they had no idea how they were being made or put together. They pulled them apart and used the pulled apart chunks with mortar to build cathedrals that mostly fell apart every time there was a tectonic movement. It breaks my heart that we don't know how to build such structures to this day. We use cement concrete which is a massive source of CO2 production. If we could have somehow preserved the knowledge of how those structures were built instead of burning their books-khippus, and killing their stone masons and scientists, we could have had a very different modern world today.
    - kiba 5y ago
      They have a whole field called experimental archaeology that's exactly about these sort of things.
      - robinsoh 5y ago
        I'm unsure what you're trying to communicate.
  - deleted 5y ago
    [deleted]
kumarvvr 5y ago
Are there any modern construction equivalents to such construction? Or have we surpassed and come up with better models?
- Zenst 5y ago
  Tuned dampning would be one of the main ways in modern times and nice read about such things :- https://blog.jumpstartinsurance.com/more-ways-to-keep-buildings-safe-in-earthquakes/ https://blog.jumpstartinsurance.com/more-ways-to-keep-buildi...
- dumbfoundded 5y ago
  Wood works pretty well. If you live in California, you don't see a lot of houses built out of brick.
  - Zenst 5y ago
    True, though costs may also be a factor. Was interested in what the oldest buildings in California would be and https://en.wikipedia.org/wiki/List_of_the_oldest_buildings_in_California https://en.wikipedia.org/wiki/List_of_the_oldest_buildings_i... Darn, you have to love arches in buildings - do seem to stand the test of times well. Also wondering if that is a lime render being used and if that is useful in dispersing resonance in the structure - I'm thinking yes.
    - dumbfoundded 5y ago
      A lime render may help: https://www.zdnet.com/article/seismic-fabric-could-protect-old-buildings-from-earthquake-harm/ https://www.zdnet.com/article/seismic-fabric-could-protect-o...
    - goto11 5y ago
      I was really confused the oldest building in California was a monastery from 1181. Apparently it was built in Spain in the middle ages, but in 1931 was purchased by an American billionaire and shipped to California!
Zenst 5y ago
Resonance would be a key factor as well, various sized rocks all at irregular angles would help greatly to prevent any overall resonance shaking and amplifying across the structure. Now in contrast to standard sized bricks and regimental formations - like a row of pitchforks just awaiting the right note in many ways. Then buildings of old had less engineering and material science to lean onto. That combined with a shift of building things to last forever towards a lifetime and even that lifetime gets shorter. We see things built with just enough materials to do the job and know more with a life of 100 years at best in so many cases (often half that with some housing). Sadly it gets down to the numbers and odds as well - if there is say 1 in 100 years chance of a quake that would be over 6 on the scale and 1 in 500 of a 7 and the cost to build is 1m for upto level 5 survivability and 5 million for level 6 and 50m for level 7. You see how the insurance can push it towards going for the cheaper option on the bases that if you went for a level 5 - you could rebuild it 5 times in that 100 years. So money does play a huge part as always. I do wonder, what would it cost today to build Machu Picchu as it is - a huge amount and can bet the modern approach would involve concrete and reinforced steel. Just can't beat natural stone still in many ways.
- mark336 5y ago
  I am Peruvian. I wonder if the Incas built there buildings with irregular rocks only to prevent resonance or because it was too difficult to carve rocks of the same size...
  - WalterBright 5y ago
    > or because it was too difficult to carve rocks of the same size The by far most likely explanation. Especially if your only tools were other rocks.
    - robinsoh 5y ago
      > Especially if your only tools were other rocks. This is not a entirely valid assumption. It has not been proven that these civilizations only had stone tools. Attempting to portray them as primitive people with only stone tools is highly reductive given the level of sophistication of the structures they managed to create. They may have had sophisticated chemical processes to shape and form rock structures. A simple proof is just by looking at these structures and seeing that even today in 2021, we are unable to form equivalent structures ourselves using modern cranes and rock shaping tools. It is terrible that the knowledge was destroyed by burning their books-khippus and extinguishing their stone masons, technicians and scientists.

kibwen 5y ago

Words don't quite do their stonework justice. Plenty of old-world architecture is made of whatever weirdly-shaped rocks they had lying around, but they use mortar to hold them together. The Incan mortar-less stone puzzle look is extremely cool: https://commons.wikimedia.org/wiki/File:Mur_Inca_D%C3%A9cembre_2007.jpg https://commons.wikimedia.org/wiki/File:Mur_Inca_D%C3%A9cemb... "Usually the walls of Incan buildings were slightly inclined inside and the corners were rounded. This, in combination with masonry thoroughness, led Incan buildings to have a peerless seismic resistance thanks to high static and dynamic steadiness, absence of resonant frequencies and stress concentration points. During an earthquake with a small or moderate magnitude, masonry was stable, and during a strong earthquake stone blocks were “ dancing ” near their normal positions and lay down exactly in right order after an earthquake."

knolax 5y ago
Don't stone walls in Europe use the same technique?
- robinsoh 5y ago
  Not to my knowledge. Almost all European stone walls all use mortar. Drystan is more like piling rocks together. They aren't shaped. The Inca (or possibly their predecessor civilization) techniques at Sacsayhuaman and Machu Picchu are far more advanced. It is still unclear exactly how they achieved those structures. We're talking about 140 tonne rocks being put together to form those structures and assembled without mortar in such a way that one can't slip a piece of paper in between rocks. When the Conquistadors encountered the structures, they had no idea how they were being made or put together. They pulled them apart and used the pulled apart chunks with mortar to build cathedrals that mostly fell apart every time there was a tectonic movement. It breaks my heart that we don't know how to build such structures to this day. We use cement concrete which is a massive source of CO2 production. If we could have somehow preserved the knowledge of how those structures were built instead of burning their books-khippus, and killing their stone masons and scientists, we could have had a very different modern world today.
  - kiba 5y ago
    They have a whole field called experimental archaeology that's exactly about these sort of things.
    - robinsoh 5y ago
      I'm unsure what you're trying to communicate.
- deleted 5y ago
  [deleted]

kumarvvr 5y ago

Are there any modern construction equivalents to such construction? Or have we surpassed and come up with better models?

Zenst 5y ago
Tuned dampning would be one of the main ways in modern times and nice read about such things :- https://blog.jumpstartinsurance.com/more-ways-to-keep-buildings-safe-in-earthquakes/ https://blog.jumpstartinsurance.com/more-ways-to-keep-buildi...
dumbfoundded 5y ago
Wood works pretty well. If you live in California, you don't see a lot of houses built out of brick.
- Zenst 5y ago
  True, though costs may also be a factor. Was interested in what the oldest buildings in California would be and https://en.wikipedia.org/wiki/List_of_the_oldest_buildings_in_California https://en.wikipedia.org/wiki/List_of_the_oldest_buildings_i... Darn, you have to love arches in buildings - do seem to stand the test of times well. Also wondering if that is a lime render being used and if that is useful in dispersing resonance in the structure - I'm thinking yes.
  - dumbfoundded 5y ago
    A lime render may help: https://www.zdnet.com/article/seismic-fabric-could-protect-old-buildings-from-earthquake-harm/ https://www.zdnet.com/article/seismic-fabric-could-protect-o...
  - goto11 5y ago
    I was really confused the oldest building in California was a monastery from 1181. Apparently it was built in Spain in the middle ages, but in 1931 was purchased by an American billionaire and shipped to California!

Zenst 5y ago

Resonance would be a key factor as well, various sized rocks all at irregular angles would help greatly to prevent any overall resonance shaking and amplifying across the structure. Now in contrast to standard sized bricks and regimental formations - like a row of pitchforks just awaiting the right note in many ways. Then buildings of old had less engineering and material science to lean onto. That combined with a shift of building things to last forever towards a lifetime and even that lifetime gets shorter. We see things built with just enough materials to do the job and know more with a life of 100 years at best in so many cases (often half that with some housing). Sadly it gets down to the numbers and odds as well - if there is say 1 in 100 years chance of a quake that would be over 6 on the scale and 1 in 500 of a 7 and the cost to build is 1m for upto level 5 survivability and 5 million for level 6 and 50m for level 7. You see how the insurance can push it towards going for the cheaper option on the bases that if you went for a level 5 - you could rebuild it 5 times in that 100 years. So money does play a huge part as always. I do wonder, what would it cost today to build Machu Picchu as it is - a huge amount and can bet the modern approach would involve concrete and reinforced steel. Just can't beat natural stone still in many ways.

mark336 5y ago
I am Peruvian. I wonder if the Incas built there buildings with irregular rocks only to prevent resonance or because it was too difficult to carve rocks of the same size...
- WalterBright 5y ago
  > or because it was too difficult to carve rocks of the same size The by far most likely explanation. Especially if your only tools were other rocks.
  - robinsoh 5y ago
    > Especially if your only tools were other rocks. This is not a entirely valid assumption. It has not been proven that these civilizations only had stone tools. Attempting to portray them as primitive people with only stone tools is highly reductive given the level of sophistication of the structures they managed to create. They may have had sophisticated chemical processes to shape and form rock structures. A simple proof is just by looking at these structures and seeing that even today in 2021, we are unable to form equivalent structures ourselves using modern cranes and rock shaping tools. It is terrible that the knowledge was destroyed by burning their books-khippus and extinguishing their stone masons, technicians and scientists.