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Article: Bridges.
- Article from:
- Science Weekly
- Article date:
- November 15, 2002
CopyrightCOPYRIGHT 2002 Science Weekly, Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Level C
Bridges
Bridges help us get across places. Some bridges go over water. Some go over land. The part of the bridge that you can walk or drive on is called the deck.
Bridges must be very strong and sturdy. A bridge not only has to support its own weight, but it must support the heavy traffic that crosses it. Most large bridges today are made of heavy materials, like concrete and steel. A bridge must also be able to stand up to all sorts of wind and weather.
Piers help hold a bridge deck up. To make a longer bridge deck, you need to build more piers. Engineers have to be careful that bridges going over water don't use too many ...