This section needs additional citations for verification. The collapse boosted research into bridge aerodynamics- aeroelastics, which has influenced the designs of all later long-span bridges. In many physics textbooks, the event is presented as an example of elementary forced mechanical resonance, but it was more complicated in reality the bridge collapsed because moderate winds produced aeroelastic flutter that was self-exciting and unbounded: For any constant sustained wind speed above about 35 mph (56 km/h), the amplitude of the ( torsional) flutter oscillation would continuously increase, with a negative damping factor, i.e., a reinforcing effect, opposite to damping. The bridge's collapse had a lasting effect on science and engineering. The portion of the bridge that fell into the water now serves as an artificial reef. Efforts to replace the bridge were delayed by the United States' entry into World War II, but in 1950, a new Tacoma Narrows Bridge opened in the same location, using the original bridge's tower pedestals and cable anchorages. The portions of the bridge still standing after the collapse, including the towers and cables, were dismantled & sold as scrap metal. The bridge's main span finally collapsed in 40-mile-per-hour (64 km/h) winds on the morning of November 7, 1940, as the deck oscillated in an alternating twisting motion that gradually increased in amplitude until the deck tore apart. The motion continued after the bridge opened to the public, despite several damping measures. From the time the deck was built, it began to move vertically in windy conditions, so construction workers nicknamed the bridge Galloping Gertie. Throughout its short existence, it was the world's third-longest suspension bridge by main span, behind the Golden Gate Bridge and the George Washington Bridge.Ĭonstruction began in September 1938. The bridge's collapse has been described as "spectacular" and in subsequent decades "has attracted the attention of engineers, physicists, and mathematicians". It opened to traffic on July 1, 1940, and dramatically collapsed into Puget Sound on November 7 of the same year. state of Washington that spanned the Tacoma Narrows strait of Puget Sound between Tacoma and the Kitsap Peninsula. The 1940 Tacoma Narrows Bridge, the first bridge at this location, was a suspension bridge in the U.S. The revenue from these citations will go towards traffic safety programs and improvements for pedestrians, bikers, and those who are disabled, according to SDOT officials.The original Tacoma Narrows Bridge on its opening day on July 1, 1940Ĥ7☁6′N 122☃3′W / 47.267°N 122.550°W / 47.267 -122.550 Since the start of the program in the spring of 2022, more than 54,000 citations have been issued. The city said the majority of citations issued from this program actually come from drivers illegally using the bus lanes. “They work similar to that, but this is just to educate people and remind them to please don’t block the intersection or use transit lanes so we can have traffic moving more smoothly.” “People do get confused if these are red light cameras or school zone cameras,” Ali said. RELATED | Downtown Seattle traffic cameras will start ticketing in March The new cameras part of this pilot program will solely be focused on enforcement with drivers in bus lanes and blocking intersections. Drivers will get a warning on their first violation, and after that it’s a $75 dollar ticket. SDOT officials said there will be a 30-day grace period to get drivers used to the new traffic enforcement. They’ll also be going in at Boren Avenue, Howell Street, and on the West Seattle bridge in September. The new cameras will be going up near the corner of Denny Way, Yale Avenue, and Stewart Street where many drivers are usually snarled up trying to get onto I-5. “It’s just to help get the roads moving and to get people safely where they need to go.” “The goal is not to write tickets, it’s really to enhance the safety on our roadways,” Mariam Ali with SDOT said. Seattle Department of Transportation (SDOT) said the goal isn’t to write tickets, but to educate drivers and prevent people from doing things like blocking the intersection, especially during busy rush hour times when a lot of drivers are trying to get in and out. RELATED | Seattle set to activate first camera in effort to catch motorists who 'block the box' The city already has eight cameras up mostly in the downtown area, but will be installing three more in South Lake Union and on the West Seattle bridge. SEATTLE - More traffic cameras are going up in Seattle in an effort to keep traffic moving and cut down on drivers blocking intersections and illegally driving in bus lanes.
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