20 8月 美国英语语言学论文代写-桥梁破坏的原因
It was concluded by the FWA that due to the extreme lightness, narrowness and flexibility of Tacoma Narrow, the randomly forcible wind ended up causing torsional oscillations as a result of which the bridge got destroyed. The theory of FWA, however, cannot be considered as the sole explanation. A number of individuals hold the belief that specifically this explanation tends to be overlooking the significant doubt as to how wind could result in the production of periodic based impulse (Hendley, 1998).
The proposal of explanation was characterized with the movement of bridge across the periodically shedded air vortices. This resulted in the creation of a wake referred to as a street of von Karman. This specific wake resulted in the reinforcement of structure based oscillation that eventually caused the destruction of the bridge. The key issue of this theory is the calculation of frequency regarding the cause of vortex at the wind velocity of 42 mph (Kardon, 2005). The key resonance among the bridge along with these vortices resulted in the cause of excessive motion that destructed the bridge. While these explanations tend to be differing in terms of opinions, this surely resulted in causing the torsional oscillations across the bridge.
There is an agreement of extreme lightness, slenderness and flexibility across the bridge allowing the growth of oscillation until their destruction (Nissenbaum, 1994). The collapse of this bridge provided evidence to the world and the engineer about the significance of torsional resistance, vertical rigidity, and dampening in each and every suspension bridge. Once there is realization of the threat to twist, there are a number of ways due to which the bridge collapsed.
The appearance was so significant to the designer of the bridge, Leon Moisseiff, that it was designed in the lack of using stiffened trusses that left the bridge with 1/3rd stiffened in comparison with the George Washington and Golden Gate Bridges (Puri and Delatte, 1998). In context with the overall advancements of technology, there has to be critical consideration of the factors to balance public welfare in accordance with the progress made. If there had been a designing of the bridge as per other designs to ensure stability, the bridge would never have been destructed. However, the bridge did provide scope for a number of inventions in the field of engineering, but by endangering a number of lives and costing a number of dollars (Haberland et al., 2012). It is the core responsibility of the engineers for eliminating situations that may cause harm to the public. This requires immensely considered ethics. Several different ethical dilemmas are further faced by the engineers. The oscillations of wind destroyed the bridge only in a period of three months. There has been an establishment of innovations for suspension bridges in the current era to counter the impacts imposed by wind, succumbing to normalize the overall deviance (Billington, 2006). There has to be a gradual acceptance of failures and errors of sequential minority. This provided a significant scope for the accumulation and culmination of a certain catastrophic event.