Skyscraper Foundations

We liked our bridges book so much, we got the companion volume on skyscrapers. It had some great information on the different types of foundations and footings used for skyscrapers on different types of soil. We did this demonstration of how concrete piles in the foundation manage the tower's weight by distributing it among themselves. It works the same way as lying or stepping on a bed of nails! You can see we put toothpicks all throughout this clay "soil," above. A building built right on the clay would slowly sink into the ground. But with these piles making up the foundation. . .

the building is very well-supported!

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We varied this a bit to demonstrate how the weight of a skyscraper is distributed more on the outer edges---allowing "tube" tower construction which makes for very strong towers, such as the Willis tower in Chicago. You can see how if we remove the inner piles, as above . . . 

The outer ones alone are able to support the structure! When we did the opposite thing (removing piles from the outside, leaving only a mass of piles in the center), the piles collapsed under the same load.

Elevator Model, and the Safety Elevator

Steel was an important advancement that made taller and taller skyscrapers possible, but equally important was the invention of the safety elevator by Elisha Otis. Tall buildings are not useful unless there are elevators to get people and equipment to the uppermost floors, and no one was willing to ride in elevators until a safety brake was invented! We made a model of an elevator (no safety brake, though!) which was pretty fun.

Arc de Triomphe is going up in this elevator

We absolutely loved this video, in which a guy makes his own model elevator and demonstrates how the safety brake works. I wish I knew how to just build things like this in my garage!

After learning about elevators, we have been noticing how many elevators still are made by the Otis Elevator company. Practically all of them! You can look for the "Otis" logo next time you ride an elevator.

Skyscrapers

After bridges, we spent an entire week on skyscrapers, as this was another area I knew the children had great interest. And who can blame them? Tall towers are just amazing!

Seb has always loved the Burj Khalifa, and has been drawing it ever since he was a small(er) guy! The picture on our left is another version of the Burj Khalifa, this one in a whirling sandstorm.

He still builds it regularly with blocks, too.

It's such a beautiful building! It would be amazing to see it in person.

Anyway, here are some resources we found for our skyscraper week.

This looks fun, but we didn't have the materials for it. 

We considered doing this to-scale city skyline too, but ran out of time. I think we may do it another time, as images like this and this are something the boys really enjoy poring over.

We watched this documentary about Dubai---dramatic in kind of a funny way, but interesting :)

This is fun---it shows the window-washing robot that washes the windows of the Sears (now Willis) Tower.

I loved this article, about the progress on the new World Trade Center (called One World Trade Center) in New York City. You can see a time-lapse video of its construction, too.

This is a documentary about the construction of One World Trade Center. Inspiring.