This activity was inspired by the WGBH production of “Structures”, produced and narrated by Bebe Nixon. In this video designed to introduce teachers to inquiry-based teaching methods, students build towers and bridges out of drinking straws and see what is the maximum amount of weight each tower or bridge can hold. I adapted this lesson as a complement to the plate tectonics unit.
Shake TableTo create your own very simple earthquake table that is more like a trampoline than a standard, motor controlled earthquake table:
- Cut a piece of board or plywood into a 12” square. If you wish, create a raised edge for your platform by nailing lengths of 1/2” square dowel on top of each of the sides.
- Mount wood screws on the under side of the plywood at each corner and at the center of each side. Don’t screw the screws in all the way, make sure at least 1/4” sticks up so you can loop a rubber band around it.
- Construct a frame out of 2” x 4”s that fits around the wood square with around 1/2” clearance between the outer edge of the square and the inside edge of the frame. Make sure the 2” x 4”s are oriented so that the frame is 4” high.
- Mount wood screws on the top edge of the frame at each corner and at the center of each side. Again, don’t screw in the screws all the way.
- Loop a rubber band around each pair of screws so that the plywood square is suspended like a trampoline within the frame.
Other earthquake table designs powered by an electric drill are described by John Lahr.
A great, very accessible resource on structural engineering principles with projects that can be adapted for the classroom is the book The Art of Construction: Projects and Principles for Beginning Engineers and Architects by Mario Salvadori, Chicago Review Press (1981).