Failure Analysis: The 1940 collapse of the Tacoma Narrows Bridge

Introduction An important element of engineer's work is to be able to meet specific needs by building or creating devices or structures to meet specific objectives. The important thing is to deal with people's lives and therefore require the highest level of security, so the device can run without failing its purpose. However, everything, such as maintenance failures and structural failures, should eventually fail in some way. This is why failure analysis is important for engineers' work.

The collapse of the Tacoma Strait Bridge on the morning of November 7, 1940 was the most representative example of modern spectacular bridge failure. As the world's third largest suspension bridge, following George Washington and the Golden Gate Bridge, it was open to the public on July 1, 1940, connecting Tacoma and the whole Kisap peninsula of Puget Sound. Only four months later, under the correct wind conditions, the bridge was moved at its resonance frequency, causing it to vibrate and infinitely distort. After an undulating wave of more than an hour, the central part collapsed and the bridge was destroyed. It proved the power of resonance and since then it has been used as a classical example of national physics and engineering course. Unfortunately, this story is a perfect myth

Tacoma Narrows Bridge is the historical name of a two-seater suspension bridge across the Tacoma Narrows Strait originally built in 1940. It collapsed after 4 months due to aerodynamic elastic vibration. Since then, this topic became very popular, and some case studies discussed suspension bridge failures. In Washington State, construction of the Tacoma Strait Bridge was completed on July 1, 1940 and it was opened. This is the first bridge to support a series of slab beams as a floor, the first such bridge. (Cable hanging) It was also the third largest suspension bridge then, there were a center span of 2,800 feet and two spans of 1,100 feet.