Author: Maddie Van Beek
At one point in your life, you have crossed a bridge. Think about the different bridges you have crossed. Were they arched? Flat? Did they have cables running through them? Were there pillars on both ends or beneath the bridge? While there are many visual and structural varieties, all bridges span a distance to get you from point a to point b. There are five main categories of bridges.
Today, you are going to be an architect! An architect is someone who designs buildings and structures so they are steadily built. Before you start building, you need to know a little more about the different types of bridges.
Bridge Types
1. Beam: The beam bridge is the simplest type of bridge. This bridge is stiff, straight, and generally short with two piers or abutments on either end. The beam bridge spans, at most, 250 feet.
At one point in your life, you have crossed a bridge. Think about the different bridges you have crossed. Were they arched? Flat? Did they have cables running through them? Were there pillars on both ends or beneath the bridge? While there are many visual and structural varieties, all bridges span a distance to get you from point a to point b. There are five main categories of bridges.
Today, you are going to be an architect! An architect is someone who designs buildings and structures so they are steadily built. Before you start building, you need to know a little more about the different types of bridges.
Bridge Types
1. Beam: The beam bridge is the simplest type of bridge. This bridge is stiff, straight, and generally short with two piers or abutments on either end. The beam bridge spans, at most, 250 feet.
Image 1: Beam bridge in Iowa City
2. Arch Bridge: Just as the name suggests, this bridge is arched. Similar to the beam bridge, this bridge has two piers or abutments. The curved design allows stress to be distributed along the arch to either end. This design can span up to about 800 feet.
Image 2: Megane Bridge in Nagasaki, Japan
3. Cantilever: The cantilever bridge is more complex than either the beam or arch bridge. From piers, horizontal structures called cantilevers extend and are joined by a third span, or beam bridge, in the middle. Cantilever bridges can span over 1,500 feet.
Image 3: An early human demonstration of a cantilever bridge
4. Cable Stayed: This bridge, like the suspension bridge, is supported with steel cables. The cables run from the road to a tower, forming an A. The cables are taught and run parallel to one another. The cable stayed design is popular for mid-length bridges, not far over 3,000 feet.
Image 4: The world's longest cable-stayed bridge, located in Vladivostok, Russia.
5. Suspension Bridge: This kind of bridge spans longer than any other type! A suspension bridge is usually between 2,000 and 7,000 feet long. As suggested by the name, the roadway of this bridge is suspended by cables attached to two towers. The supporting cables run horizontally from the tops of the towers to the anchorages, or concrete blocks at either end of the bridge. The suspenders, parallel to one another, run vertically from the supporting cables to the roadway.
Image 5: Manhattan Bridge in New York
Use the following bridge diagrams as a reference:
YOU WILL NEED:
• Paper/Pencil
• 42 Gum Drops
• 7 Red
• 10 Green
• 8 Yellow
• 9 Orange
• 6 Purple
• 2 White
• One bag of toothpicks
Here's what to do!
1. Partner up with one to three others.
2. Assign a runner to get supplies, a time-keeper, and a group leader.
3. Design your bridge. Before you start building, you need to plan. You should be able to answer these kinds of questions:
a.What kind of bridge will you design?
b. Will you rely on one type of bridge, or will you combine two types for a more elaborate design?
c. What criteria are you basing your decisions on? Attractiveness? Strength?
d. How far will your bridge span? How high do you want your bridge to be?
4. Use your gumdrops and toothpicks to build a bridge based off of one of the five bridge types. Use your drawing to guide you.
a. Once you are finished building, you will be judged based on strength and appearance.
6. For the last ten minutes, try building your bridge in silence. All team members must continue to participate.
7. Stack pennies on your bridge to see how many it will hold! Have a contest to see who has the strongest bridge.
Follow-up Questions:
Image Credits:
Image 1: Jones, D.W. (2006). Steam across Iowa river. Retrieved from https://upload.wikimedia.org/wikipedia/commons/thumb/1/10/SteamAcrossIowaRiver.JPG/240px-SteamAcrossIowaRiver.JPG
Image 2: Bulwersator. (2004). Double arch stone bridge, Japan. Retrieved from https://en.wikipedia.org/wiki/Arch_bridge#/media/File:NagasakiMeganebashi.jpg
Image 3: Unknown photographer. (1890). Postcard of Benjamin Baker's human cantilever bridge model. Retrieved from https://en.wikipedia.org/wiki/Cantilever_bridge#/media/File:Cantilever_bridge_human_model.jpg
Image 4: Bayakov. (2013). "Russian bridge" in Vladivostok. Retrieved from https://upload.wikimedia.org/wikipedia/commons/thumb/e/eb/%22Russian_bridge%22_in_Vladivostok.jpg/1280px-%22Russian_bridge%22_in_Vladivostok.jpg
Image 5: Underhill, I. (1909). Manhattan bridge construction 1909. Retrieved from https://upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Manhattan_Bridge_Construction_1909.jpg/800px-Manhattan_Bridge_Construction_1909.jpg
References:
List of bridge types. (2016). Wikipedia. Retrieved from https://en.wikipedia.org/wiki/List_of_bridge_types
• Paper/Pencil
• 42 Gum Drops
• 7 Red
• 10 Green
• 8 Yellow
• 9 Orange
• 6 Purple
• 2 White
• One bag of toothpicks
Here's what to do!
1. Partner up with one to three others.
2. Assign a runner to get supplies, a time-keeper, and a group leader.
3. Design your bridge. Before you start building, you need to plan. You should be able to answer these kinds of questions:
a.What kind of bridge will you design?
b. Will you rely on one type of bridge, or will you combine two types for a more elaborate design?
c. What criteria are you basing your decisions on? Attractiveness? Strength?
d. How far will your bridge span? How high do you want your bridge to be?
4. Use your gumdrops and toothpicks to build a bridge based off of one of the five bridge types. Use your drawing to guide you.
a. Once you are finished building, you will be judged based on strength and appearance.
6. For the last ten minutes, try building your bridge in silence. All team members must continue to participate.
7. Stack pennies on your bridge to see how many it will hold! Have a contest to see who has the strongest bridge.
Follow-up Questions:
- How well did you work together as a group?
- How much harder was it when you couldn’t talk?
- Do you feel like everyone was included in your group?
Image Credits:
Image 1: Jones, D.W. (2006). Steam across Iowa river. Retrieved from https://upload.wikimedia.org/wikipedia/commons/thumb/1/10/SteamAcrossIowaRiver.JPG/240px-SteamAcrossIowaRiver.JPG
Image 2: Bulwersator. (2004). Double arch stone bridge, Japan. Retrieved from https://en.wikipedia.org/wiki/Arch_bridge#/media/File:NagasakiMeganebashi.jpg
Image 3: Unknown photographer. (1890). Postcard of Benjamin Baker's human cantilever bridge model. Retrieved from https://en.wikipedia.org/wiki/Cantilever_bridge#/media/File:Cantilever_bridge_human_model.jpg
Image 4: Bayakov. (2013). "Russian bridge" in Vladivostok. Retrieved from https://upload.wikimedia.org/wikipedia/commons/thumb/e/eb/%22Russian_bridge%22_in_Vladivostok.jpg/1280px-%22Russian_bridge%22_in_Vladivostok.jpg
Image 5: Underhill, I. (1909). Manhattan bridge construction 1909. Retrieved from https://upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Manhattan_Bridge_Construction_1909.jpg/800px-Manhattan_Bridge_Construction_1909.jpg
References:
List of bridge types. (2016). Wikipedia. Retrieved from https://en.wikipedia.org/wiki/List_of_bridge_types
