At-Home Science Experiments: Bridge Building
By: Rocky the Rock Ripper
At our last science fair, the team behind Port Lands Flood Protection created activities and experiments to help people learn more about the science, technology and engineering that go into making a new river, parks, roads and bridges.
See if you can replicate this experiment from our last science fair at home. Then, come meet our team on Saturday, September 10, 2022 at The Bentway, and try all the new activities! Learn more here.
Lego is a great tool to experiment with different bridge building techniques.
The EllisDon team provided different types of bridges to experiment with. As part of the Port Lands Flood Protection Project, we will be building several bridges – some for cars, some for transit and some for pedestrians and cyclists. Some of the new bridges will go over the existing Keating Channel, while others will help people cross the new river valley.
What are some of the different types of bridges?
Download the images of different bridges here (PDF).
Beam Bridge
Beam bridges are the simplest type of bridge. It is basically a long beam that is supported at each end. Longer beam bridges sometimes have some supports in the middle, too. If the supports are far apart, the bridge is not as strong.
Truss Bridge
A truss bridge is supported by triangular sections called trusses. These trusses give additional support to longer bridge since triangles are not easily distorted by stress.
Arch Bridge
Arches support a bridge by distributing its load horizontally. They have been used for thousands of years to create long, strong bridges.
Suspension Bridge
Suspension bridges use tension to support the bridge. The load on the bridge is transferred to the suspension cables and distributed across the entire bridge.
Cable-Stayed Bridge
These bridges have one or more towers along its length. Cables run diagonally from the towers to the bridge deck to provide support.
Now, let’s try the experiment at home
This budding engineer is making an arch bridge out of Lego.
What you’ll need:
- Lego, k’nex, or other interlocking building blocks
- A drawing of a river (optional)
- Heavy things to test the bridge’s strength
- Reference pictures of the different types of bridges (PDF)
How to do the experiment:
- Optional: Draw a river on a piece of paper. Make sure to include a riverbank on either side of the river. The wider you make your river, the more challenging it will be to build a strong bridge.
- Look at the different types of bridges in the PDF file
- Use the Lego, k’nex or other building blocks to make each type of bridge.
- Test the bridge’s strength – see if it will hold up a heavy book, canned food, or other objects. Which bridge is the strongest?