Tacoma Narrows Bridge

The Tacoma Narrows Bridge was a suspension bridge that spanned the Tacoma Narrows strait of Puget Sound in the state of Washington, USA. It was opened on July 1, 1940, and collapsed on November 7, 1940, due to violent wind-induced vibrations.

The bridge was designed by Leon Moisseiff, a prominent suspension bridge engineer, and it had a total length of 5,989 feet and a main span of 2,800 feet. The roadway was suspended from two 426-feet-high towers by steel cables, and it had a width of 39 feet.

On November 7, 1940, strong winds of up to 42 mph hit the bridge, and the deck began to sway and twist violently. The oscillations increased in amplitude until they became so violent that they caused the roadway to collapse, plunging into the water below. Fortunately, no one was killed in the collapse, but one dog was famously caught on film running across the bridge during the event.

The collapse of the Tacoma Narrows Bridge was a major engineering disaster and resulted in significant changes in bridge design and construction. The incident prompted further research into the aerodynamics of long-span bridges and led to the development of more sophisticated modeling techniques to predict their behavior in high winds.