What Decides a Skyscraper Foundation Depth?

Anyone who looks at a skyscraper can automatically enjoy the architectural genius that clearly went into the skyscraper. However, did you know that the foundation is just as important, if not more important, than the rest of the skyscraper? After all, if you don’t have a secure foundation, you could end up with the possibility of very serious concerns. Here are the elements that might impact the depth of skyscraper foundations.

The Skyscraper Design

Of course, the skyscraper design itself is a big part of understanding how deep the foundation for the skyscraper has to be. For example, the Burj Khalifa is extremely tall – it reaches over a mile in the air – and yet its foundation, at 164 feet in depth, is over 100 feet shallower than the foundation for Shanghai Tower, which is nearly 700 feet shorter.

The difference may lie in the fact that the Burj Khalifa has an extremely wide base – it essentially has one extremely tall building surrounded by a number of shorter buildings. That wide base allows the Burj Khalifa to get away with a much shorter foundation because the Burj Khalifa doesn’t have to rely on that foundation completely.

Soil Composition Under the Skyscraper

The soil under the skyscraper may have an impact on the depth of the foundation as well. For example, if a company wants to build a skyscraper on relatively sandy soil, they’re going to have a much more difficult time than if they want to build a skyscraper on extremely hard-packed soil. In less sturdy soil situations, the foundation will likely need to be deeper.

Depth to Bedrock

Bedrock is where most designers want to anchor their foundations. That’s because the bedrock isn’t going to move or shift the way soil might. Depending on how deep bedrock is, a foundation may have to be more or less deep – bedrock being closer to the surface means that the foundation will probably not have to be as deep as if the bedrock is pretty far down.

General Environmental Risk

Environmental risk can come in a variety of ways, ranging from the possibility of earthquakes to high winds and issues with water in the soil. When dealing with environmental risk, it’s important to remember that there’s not really any way to mitigate the environmental risk, so designers instead have to make sure a building can remain standing through it.

For example, the One World Trade Center, which is in NYC and is 1,776 feet tall, has a foundation depth of 150 feet. However, Taipei 101, which is in Taiwan and is 1,667 feet tall, has a foundation depth of 262 feet. Because China is more prone to earthquakes, the designers of Taipei 101 may have felt like it needed a deeper foundation.

Conclusion

Understanding how a skyscraper foundation works can be a great way to recenter your love of skyscraper architecture. Sure, skyscrapers are architectural wonders no matter where they’re built or how deep their foundation is, but the foundation is certainly a crucial part of the skyscraper.