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Body Building

Feel in your body the pressure, stretching, and bending that architects--and the structures they design--must contend with!


Column figure diagram
A column resists compression. Balance a pile of books on your head to feel compression.


Cantilever figure diagram

A cantilever balances weight on one side of a beam with weight on the other side. The beam must be strong enough to resist bending or it will break. To feel this being force, try to hold the same pile of books at arm's length!


Arch figure diagram

An arch uses compression to balance its own weight and the weight piled on top of it. Build an arch with two people leaning against each other's hands. How far apart can you and your partner stand before your arch begins to collapse? Where in your body do you feel the most pressure? What could you do to "buttress" your arch?

Vaulted roof

Vault figure diagram

Medieval architects solved the problem of creating a soaring roof over a large cathedral sanctuary by inventing the vaulted roof. The ribs of a vaulted roof are huge arches arranged side-by-side and buttressed at the base to keep them from spreading. How could you buttress your human vault?


An arcade is created when arches are lined back-to-back. Arches in an arcade buttress each other. Arcades are often used to create covered walkways.

Arcade figure diagram


Dome figure diagram

A dome works like many arches arranged in a circle. Start to make a dome by having two people make an arch, learning their hands agains a large rubber ball. Keep adding pairs until there is no more room. What would happen if someone took the ball away?


Catenary figure diagram

A catenary, often seen in suspension bridges, is almost the opposite of an arch. Only steel cables are strong enough to result this kind of tension. You can feel the tension of a catenary bridge and the compression the piers that hold it by having two people pick up a third by the wrists and ankles. Is there more tension with the "piers" stand closer together of further apart? Is there ever a happy medium?

Source: Exploring Architecture Curriculum, Susan Donley, Pittsburgh History & Landmarks Foundation, 1987.

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