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.
"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."
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.
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.
The by far most likely explanation. 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.
It hasn't been proven that space aliens didn't create the masonry walls, either. (Yes, I've seen TV shows arguing that case.)
But archaeologists have shown that rocks can be shaped accurately in the manner of those walls by just banging them together. There is also the evidence of partially shaped rocks left behind.
There is no evidence of any other method.
I've been to Chichén-Itzá and have looked at the structures from an engineer's point of view, as I am a mechanical engineer. They are solidly built, massive, and well built. The scale is impressive. Very impressive. But the sophistication does not extend past the corbelled vault. They did not use an arch or a dome.
https://www.maya-archaeology.org/pre-Columbian_Mayan_temples...
The Mayan script has been shown to be phonetic, so they certainly had a solid writing system. But, sadly, we know very little about what they wrote about, since the Spanish burned their books.
I never called them primitive.
There's no need to be disrespectful and attempt to portray my position as if it is something ridiculous and requires belief in space aliens. As I said, I think what was built was very sophisticated, and I don't find the claim that it was built just by "banging rocks together" to be satisfactory especially since no one has been able to reproduce an equivalent structure using this method.
> I never called them primitive.
How would you interpret and contextualize your remark "your only tools were other rocks"? To me, it seems like you're trying to insinuate and put in the mind of the reader exactly that you believe that they were primitive and lacked sophisticated tools.
> archaeologists have shown that rocks can be shaped accurately in the manner of those walls by just banging them together.
I have not seen such a conclusive proof. I'd like to see this proven by building an equivalent structure to Sacsayhuaman, at least perhaps even a corner. That alone would be impressive.
I also saw a show once that said that in one of the Mexican sites they found an underground canal and a pool with mercury. Don't know if they somehow used that to cut their rocis.
Presumably you go find the closest matching rock you already have and then work from that.
Or have we surpassed and come up with better models?
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.