| Abstract: |
| \textbf{\textcolor{blue}{Just}} four months after the opening of the first Tacoma Narrows Bridge, in 1940, it suffered collapse in a wind of about 42 miles per hour. The 2,800-foot main span, which had already exhibited a marked flexibility, went into a series of torsional oscillations whose amplitude steadily increased until the convolutions tore several suspenders loose, and the span broke up. An investigation disclosed that the section formed by the roadway and stiffening plate girders did not absorb the \textbf{\textcolor{blue}{turbulence of wind gusts}}. At the same time, the narrow two-lane roadway gave the span a high degree of flexibility. This combination made the bridge highly vulnerable to \textbf{\textcolor{blue}{aerodynamic forces}}, insufficiently understood at the time. The failure, which took no lives because the bridge was closed to traffic in time, spurred aerodynamic research and led to important advances. The plate girder was abandoned in suspension bridge design.
In this talk we will remodel the bridge and analyze in terms of Partial Differential Equation. |
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