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Article: Bridges. (brief history of materials used to make bridges and their designs; types of stress on bridges)
- Article from:
- Science Weekly
- Article date:
- December 20, 1995
CopyrightCOPYRIGHT 1995 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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A wide river, a deep valley, or even a busy street can be difficult to get across. Bridges can help us travel more quickly and directly to the other side.
Building Materials
For hundreds of years, bridges have been built using materials like rope, wood, stone, and iron. The ancient Romans discovered concrete and became master bridge builders. Many of their bridges are still standing today. Steel is now used for most large bridges. Even concrete bridges use steel rods to reinforce and strengthen the concrete.
Bridge Designs
Bridges must be strong and sturdy. A bridge not only has to support its own weight, but it must support the heavy traffic ...