ADOT Kids Activity: Get to know bridges!

April 22, 2020

EDITOR'S NOTE: During this unprecedented time, ADOT is creating transportation activities for kids. Please visit azdot.gov/ADOTKids or use the hashtag #ADOTKids on ADOT's Twitter, Facebook and Instagram accounts to see what we have going on.

By Garin Groff / ADOT Communications

Do you like building things? How about rock climbing? Or flying drones? If any of those things sound fun to you, then you might enjoy becoming somebody who designs and builds bridges.

Bridges are an important part of helping people get around your town and to other parts of Arizona. Think of all the times you cross bridges. They go over rivers, washes, canals, railroad tracks and even other roads – they can be just about anywhere!

It’s really cool to watch bridges being built. Just take a look at this video to the right and you can see a 2016 ADOT bridge project on Interstate 15 in the northwestern corner of Arizona.

What does it take to build a bridge? First, you need people who have studied a lot of math and science. When they learn certain types of math and science, they can become engineers – people who design and build things.

After engineers design a bridge, construction begins. Workers drill holes up to 100 feet into the ground for the foundation, then fill the holes with concrete and steel. On top of that, more concrete and steel are used to make piers. Then on top of the piers, huge cranes lift large metal or concrete sections called girders. Finally, concrete is poured on top of the girders for the roadway.

All that work usually takes 9-12 months.

After bridges are built, workers sometimes need to inspect bridges to make sure they are well-maintained. It’s not easy getting to all the places underneath a bridge, but some of the ways to get there seem fun! Some workers rappel off the sides of bridges like rock climbers. And sometimes, we fly drones to look under bridges.

Bridges are built strong enough to last 75 years but can last even longer with good maintenance. When it is time to replace and tear down a bridge, you might be surprised at one way to do it – with explosives! Check out this video of the 2016 Hell Canyon Bridge demolition north of Prescott to see how fast a bridge can be demolished.

I hope you know a lot more about bridges now. And I want to tell you about ADOT’s bridge design manager, David Benton. He is a civil engineer, a person who designs things like bridges, roads, dams or airports. He first thought about construction and engineering when he spent a lot of time playing in the mud as a kid.

“If you like to build things out of mud and like to shape things out of mud, that’s what it’s like to build with concrete,” he said. “I remember a teacher said if you like to build things and you’re good at math, civil engineering is a good profession.”

Mr. Benton has kindly volunteered to answer questions you send us about bridges when you complete this week's ADOT Kids activity:

DRAW A BRIDGE AND SEND IT TO US: We've provided a coloring sheet below with a highway that needs a bridge to be complete. When you draw your bridge, have an adult scan or take a picture of your drawing and email it to [email protected]. If you don't have a printer handy, feel free to create your own bridge drawing from scratch and share it with us. NOTE: We've included a slideshow below with all pictures that were sent to us.

To provide inspiration, we've included a slideshow below with pictures of bridges so you can see the creative ways engineers design how to support them. As you look through the photos, think about how you will support your own bridge.

We'll add every drawing we receive by 5 p.m. Wednesday, April 29, to a slideshow and put it right here on Friday, May 1, so you can see your masterpiece along with everyone else's. We've included spaces for you to include your first name (only your first name, please), your age and where you live. We can't post photos of you with your art, but we'd love to show just your art.

SEND US QUESTIONS: When an adult emails your picture to [email protected], please send us questions you have about bridges. We'll share the most popular questions with Mr. Benton, the ADOT engineer who knows A LOT about bridges. NOTE: We've included a video below with Mr. Benton's answers.

I can't wait to see what you do with these drawings and to see what questions you have about ADOT bridges!

Slideshow with examples of bridges: