Many different types of engineers work in designing bridges to suit all of our different needs. From mechanical to civil and even materials engineers, many professionals work in creating better and safer bridges. Read the following articles to learn more about bridges and engineering.
- Forces in Bridges
- Types of Bridges
- Famous Bridges of the World
- Bridge Disasters
- Types of Engineering
Bridge Disasters
Engineers must be concerned about safety at all times. Lives are at stake when bridges collapse so engineers must design bridges to withstand all kinds of weather conditions, ground types and loads. While the goal is to have no design fail, engineers examine and learn from past mistakes to avoid such failures in the future.
- Hyatt Regency Walkway Collapse, Kansas City, Missouri (failed in 1981)
- Point Pleasant/Silver Bridge, Ohio River (failed 1967)
- Tacoma Narrows Bridge, Tacoma, Washington (failed in 1940)
- Falls View Bridge, Niagara Falls (failed 1938)
- Quebec Bridge, St. Lawrence River (failed 1907,1916)
- Tay Bridge, Scotland (failed in 1879)
Tacoma Narrows Bridge Disaster
The Tacoma Narrows Bridge was a suspension bridge built on 1940 in Tacoma, Washington. The designing engineer was Clark Elderidge, but Leon S. Moisseiff made several structural changes to make the bridge lighter. The longest suspension bridge of the time, Tacoma Narrows had a length of over 5939 feet and connected the Tacoma and Gig Harbor.1
Four months after it was built, the bridge collapsed on November 7, 1940. While under construction, 4 mph winds caused the bridge to have minor oscillations. Unfortunately, on November 7, winds of 40 mph hit the bridge causing it to create waves from 5 to 28 feet high causing the bridge to eventually collapse.2 Below you can see several pictures of the bridge as it was oscillating:
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Tacoma Bridge Oscillating3 |
Tacoma Bridge Collapsing4 |
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Total Collapse of the Bridge5 |
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Today, engineers still debate over the specific cause of the Tacoma Narrows Bridge collapse. After the collapse, an investigation was led by the Federal Work Agency, who found that the actual load was 1.5 times less than it was required. Other possible contributing factors for the collapse were the lightness and flexibility of the bridge.6
For more information about this disaster, visit: http://www.enm.bris.ac.uk/research/nonlinear/tacoma/tacoma.html