Earthquake Shake

• Materials to build a bridge – these could be Lego bricks, straws, paddle pop sticks or anything else you can think of!
• Blu-tac (optional)
• 2 pieces of cardboard
• 4 balls (ping pong, tennis or golf balls will work!)

1. Use your materials to build a bridge, being as creative as you like! How could you design your bridge to make it as strong as possible? Use materials like blu-tac to help your bridge stay together if you need. 
2. Put a piece of cardboard on a flat surface. 
3. Set 2 balls on each end of the cardboard and put the other piece of cardboard on top. You’ve made your shake table!
4. Place your bridge on top of the shake table.
5. Move and shake the top piece of cardboard to create an earthquake! Can your bridge withstand the earthquake? 

Put your bridge to the test on a shake table! 

Earthquakes are usually caused by tectonic plates, which are the large pieces of the Earth’s crust. As the tectonic plates move, they can build up lots of pressure, which is released suddenly. This sudden release sends shockwaves through the crust, which is felt on the surface as an earthquake! By balancing the cardboard on top of the balls, you can move your bridge from side to side, mimicking one of the types of earthquake waves. 

To make a structure that can stay safe during an earthquake, engineers need to use different techniques. A large base gives the structure more stability, using shapes like triangles to create a cross-brace spreads out pressure, and flexible materials that absorb shock. Can you see any of these techniques in your design? 
 

Here are a few famous earthquake-proof buildings from around the world:

1. Taipei 101 — Taipei, Taiwan
2. The Transamerica Pyramid — San Francisco, California
3. Philippine Arena — Santa Maria, Philippines
4. The Yokohama Landmark Tower — Yokohama, Japan
5. Burj Khalifa Bin Zayed — Dubai, United Arab Emirates