History Of The Tacoma Narrows Bridge

The Tacoma Narrows Bridge, was also known as the Galloping Gertie, was one of the most famous cause study of structure failure in the world. The idea for constructuring of the bridge came up in the date back to 1889 with a Northern Pacific Railway proposal for a trestle. Then after a few yerars of concreted and construction with the cost of over 6,400,000 dallors, the bridge was been build and became the third longest and the most flexible suspension bridge in the world of its time of 1900s with a toatl length of 1810m. It was designed as a twin suspension bridge which located between Tacoma and the Kitsap Peninsula in United States. The Tacoma Narrows Bridge opened for traffic on July 1, 1940. After being in service for 129 days, unfortunately, the failure occurred at the late morning of Novermber 7, 1940 under a high wind condition. Then a new bridge was build as replacement which opened on 1950 and still remained today as the westbound lanes of the present-day twin bridge complex. Compare with other types of bridges, suspension bridge can span the longest distance without using lots of material. However, if the issue of stiffness was not fully cosidered, vibration would be occurred on the bridge deck under high wind. A few week after the Tacoma Narrow Bridge was operated, the bridge start oscillation and its oscillation kept increasing day by day. Therefore engineers tried to build more cable between the bridge, but it is still unsuccessful. After four months the Tacoma Narrows Bridge was build, the bridgre which normally vibrated in a vertiacal motion, began to oscillate with the opposite side out of phase (torsional model), under the wind of 68 km/h. Due to the extremely violent oscillation, the failure bagan at the mid-... ... middle of paper ... ...e, wind tunnel testing should be performed to verify the design of the new bridge prior to its construction. As an example of resonance, the destruction of the Tacoma Narrows Bridge remains a firm favourite with educators engineers at all levels. What recent studies show is that the motion of the bridge cannot be simply explained like a resonance experiment in a school laboratory. The interactions of forces, especially in a dynamic situation, become a great deal more complex. It was this that was not foreseen by the designers of the bridge in their use of new methods for lighter, flexible bridge design. However, the fact that it has been some 50 years until a more convincing theory as to the destruction of the bridge has been developed goes some way to exonerating the original designers and gives plenty of information for thought for bridge designers in the future.