Bridges, Buildings and Aircraft

Our purpose is to explore structures from the practical point of view. Bridges shorten journeys. Buildings allow more people to live in a given area. Aircraft are light but strong, and they are probably the most advanced form of structural engineering today.

Monday: The Brooklyn Bridge

We all drew our impressions of The Brooklyn Bridge and tried to label the parts and what they do. We had 16 students and 16 very different pictures. Then Richard showed us how the bridge worked starting from the idea that everything was for the purpose of holding up a roadway between the two shores. We learned that holding things up with “skyhooks” was not only difficult, it was impossible. We learned how the basic bridge structure could serve the same purpose, however.

Then we toured the Brooklyn Bridge and witnessed the sizes, vibrations and actual parts we had studied in class. The best part came when we redrew our pictures of the bridge without looking at our first pictures. Most of our pictures showed that we had learned a lot about how a suspension bridge worked. Some examples will follow soon just below.

Tuesday: Building our own bridges ( and testing them until they broke! )

We learned just enough about the strong points of a heavy paper called card stock to be able to begin to use its strengths to build bridges about 28 cm long. We then placed them on a special test stand and added weights to a platform that was supported by our bridge. When we saw that it was starting to break, we noted how it was failing and went back to improve our designs.

Wednesday: Liberty Science Center – The Skyscraper Exhibit

We spent an hour and a half in the new skyscraper exhibit here where we could get our hands on many examples of how a tall building is constructed, how it can withstand an earthquake and how it feels to walk along narrow I-beams high above the street. We played with an elevator model and learned how pulleys and cables can make raising a heavy elevator car an easy job. Some of us got to operate a backhoe and move dirt around, while others picked up construction blocks with a crane. Just about everyone rode the motion simulator. No one got sick.