Foundations. Depending on the soil composition in the area, most city skyscrapers have massive steel or concrete rods driven deep into the ground, usually into the solid bedrock beneath the soft soil, that keep the building upright.
The foundation and support structure of tall skyscrapers will be deep and thick enough to support the building without tipping over. In many places that involves drilling directly into bedrock deeper underground than any ordinary house foundation would go.
If you look at where the tallest buildings are in Manhattan they are in clusters. That’s because the rock is hard enough in those places to go taller without sinking. E.g. https://imgur.com/xkk6Nao
Actually, they do sink into the ground. It’s just a slow process. The Millennium Tower has sunk over a foot now. New York skyscrapers are sinking about 2mm yearly now.
Most foundations are secure and stable, but sinking still happens.
I used to do geotech drilling. We were the first people on site before anything gets done and we would drill down and take samples every 2.5 feet to test the soil for how it compacts and whatever else the techs were looking for. We would also be drilling to see how far down bedrock is. If the soil was too soft they wouldn’t build. Or they would sink pilings down to the bedrock
There’s a good 60 Minutes segment about The Millennial Tower. Rich people can’t sell and are suing but have lost millions. Boo hoo. But seriously, it does happen. https://youtu.be/qKtlZc-u9TU?si=xXhlHCRjtfbcJ9TC
They do sometimes, but we have geologists who make sure that the ground you are building on is safe to be built on. You’ll find that a lot of buildings with skyscrapers like nyc have very hard rock beneath them. Even with that though, those cities still ARE sinking.
“in all 28 cities they looked at (using satellite-based radar measurements) at least 20 percent of the urban area is sinking while in 25 of those 28 cities it’s at least 65 percent of the urban area that’s going steadily downwards.”
“buildings, roads and bridges are at threat of damage as the ground beneath them gives way slowly.”
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Foundations. Depending on the soil composition in the area, most city skyscrapers have massive steel or concrete rods driven deep into the ground, usually into the solid bedrock beneath the soft soil, that keep the building upright.
They’re not built on soft soil.
The foundation and support structure of tall skyscrapers will be deep and thick enough to support the building without tipping over. In many places that involves drilling directly into bedrock deeper underground than any ordinary house foundation would go.
Foudations – as they used to say ‘you’ve got to dig down to build up’
If you look at where the tallest buildings are in Manhattan they are in clusters. That’s because the rock is hard enough in those places to go taller without sinking. E.g. https://imgur.com/xkk6Nao
Actually, they do sink into the ground. It’s just a slow process. The Millennium Tower has sunk over a foot now. New York skyscrapers are sinking about 2mm yearly now.
Most foundations are secure and stable, but sinking still happens.
I used to do geotech drilling. We were the first people on site before anything gets done and we would drill down and take samples every 2.5 feet to test the soil for how it compacts and whatever else the techs were looking for. We would also be drilling to see how far down bedrock is. If the soil was too soft they wouldn’t build. Or they would sink pilings down to the bedrock
Others have covered how it’s supposed to be done right.
Here’s an example of what happens when you do it wrong, by taking a cheaper shortcut with your foundations.
https://buildingelements.com/nycs-billion-dollar-mistake-the-leaning-tower-of-new-york/
There’s a good 60 Minutes segment about The Millennial Tower. Rich people can’t sell and are suing but have lost millions. Boo hoo. But seriously, it does happen. https://youtu.be/qKtlZc-u9TU?si=xXhlHCRjtfbcJ9TC
They do sometimes, but we have geologists who make sure that the ground you are building on is safe to be built on. You’ll find that a lot of buildings with skyscrapers like nyc have very hard rock beneath them. Even with that though, those cities still ARE sinking.
“in all 28 cities they looked at (using satellite-based radar measurements) at least 20 percent of the urban area is sinking while in 25 of those 28 cities it’s at least 65 percent of the urban area that’s going steadily downwards.”
“buildings, roads and bridges are at threat of damage as the ground beneath them gives way slowly.”
https://www.ladbible.com/news/us-news/new-york-28-us-cities-sinking-529193-20250511
https://youtu.be/VpJ4AjsYp4A?si=0gLXeTtqKCAjZq-S
Burj Khalifa apparently uses friction with sands using piles.
https://practical.engineering/blog/2022/1/4/why-buildings-need-foundations
This guy has YouTube videos for all of it, too.
I’m actually kinda curious where you happen to learn that skyscrapers were built on soft soil.