Ethical Issues from the Tacoma Narrows Bridge Collapse.
A suspension bridge (more precisely, suspended-deck suspension bridge) is a type of bridge in which the deck (the load-bearing portion) is hung below suspension cables on vertical suspenders. The first modern examples of this type of bridge were built in the early 1800s. Simple suspension bridges, which lack vertical suspenders, have a long history in many mountainous parts of the world.
For students at all levels the most striking visual images are those of this from MANGEMENT 001 at Bahria University, Lahore.
A suspension bridge is a type of bridge in which the deck (the load-bearing portion) is hung below suspension cables on vertical suspenders. The first modern examples of this type of bridge were built in the early 19th century. Simple suspension bridges, which lack vertical suspenders, have a long history in many mountainous parts of the world. This type of bridge has cables suspended between.
Vortex shedding downwind of the deck exacerbated the oscillations. The torsional oscillations were usually adequately damped by the stiffness of the bridge deck, but with the unfortunate combination of high wind speed and a snapped support cable (occurring on 7 November 1940), the damping declined to near zero. At this point, the torsional oscillations grew ever larger, until the bridge collapsed.
The original Tacoma Narrows Bridge design by Clark Eldridge was pretty conventional for a suspension bridge, but it was later modified by Leon Moisseiff to be slimmer and more elegant. The most notable change was that the 25 foot lattice of stiffening trusses underneath the bridge on the original drawings, were replaced with 8 foot solid steel plate girders. The new solid girder along the side.
Due to the fact that Farquharson was present that day studying the bridge, its col- lapse is well documented, photographed and recorded on film.4 The Federal Works Agency (FWA) inves- tigated the collapse of the Tacoma Narrows Bridge and found the following: 0 The bridge was well designed and well built. While it could safely resist all static forces, the wind caused the extreme undulations.
Van Karman is most famous, perhaps, for his role in adjudicating what to do after the collapse of the Tacoma Narrows bridge - arguably a Black Swan event. One day not long after this long suspension bridge was erected, it began twisting and oscillating in a 50 MPH wind. Some minutes later it collapsed. Von Karman was called in to evaluate what happened. He told the town council that the vortex.