In the web article “I-5 and the Physics of Bridge Collapses”, Hartsfield (2013) claimed that the concept behind a functional bridge design is what leads to its failure as well. The article examined the various types of bridges and found that different types of bridges have weaknesses specific to themselves.
One such example stated by the article are truss bridges, which use geometric shapes as a basis for its strength and stability. As such, the article remarked that deformations on the shape will cause the bridge to fail.
Suspension bridges fail due to its inability to withstand huge external forces. The article observed that “when an external force causes the bridge to vibrate at its resonant frequency, it causes the vibration to grow stronger and stronger”.
Another example of such a phenomenon are cantilever bridges. The article alleged that cantilever bridges are designed to be able to withstand the torque that the lever arm takes, yet failures are found to be due to construction oversight and overestimation of the torque it can take. The article concluded that understanding a bridge’s weaknesses is indispensable to uncovering the reason behind an unforeseen failure. While the article did a great job at informing the public about the various inherent weaknesses in bridge design, it could have mentioned the other factors which can have an impact on said weaknesses.
Despite the flaws in bridge design, it is unlikely that the flaw itself is the only reason leading to the collapse of the bridge. Bridges are designed with the assumption that there will be a certain degree of servicing, to which negligence in doing so tends to lead to a bridge failure prematurely. This is supported by Grabianowski (n.d) who implied that rigorous inspections and maintenance could avert bridge collapses. In my opinion, while it is important to know the reasons behind the collapse of a bridge, attention should also be brought to the factors which can contribute to a collapse, to which a major role is played by rigorous inspections and maintenance. While it may not be a contributing factor to the collapse of the I-5 bridge, raising the awareness on the importance of inspections and maintenance can help towards preventing a similar tragedy from happening again.This si expecially important as Horgan (2019) observed that there was an increasing trend in bridge collapses due to inadequate maintenance.
Apart from factors that can magnify the flaws, there are also factors that can help to mitigate or control the weaknesses. When a flaw is identified, measures could then be taken to help mitigate or control factors which can contribute to magnifying the flaw. For instance, I feel that road barriers could be erected near the crucial supports to reduce the impact of collisions on the crucial supports. Implemented guidelines based on research can also be the deciding factor for when a bridge collapses. For example, it is found that the shape and size of a column can affect its blast resistance (The University of Texas at Austin Civil, Architectural and Environmental Engineering, n.d), and having it implemented in guidelines would ensure that bridges would be more resistant to blast from terrorist attacks.
Although this article did well to inform the public on how inherent design flaw in bridges can cause its collapse, failure to mention factors which can impact the bridge could lead to an unfortunate misunderstanding by the public. They should include other factors apart from inherent design flaws so that readers can get an objective view on the reasons behind bridge collapses.
Grabianowski, E. (n.d). 10 Reasons why bridges collapse. Howstuffworks.com. Retrieved from https://science.howstuffworks.com/engineering/structural/10-reasons-why-bridges-collapse.htm
Hartsfield, T. (2013, May 28). I-5 and the physics of bridge collapse. RealClear Science.com. Retrieved from https://www.realclearscience.com/articles/2013/05/29/i-5_and_the_physics_of_bridge_collapses_106544.html
Horgan, R. (2019). Fatal Taiwan bridge collapse is latest example of maintenance failings. New Civil Engineer.com. Retrieved from https://www.newcivilengineer.com/latest/fatal-taiwan-bridge-collapse-is-latest-example-of-maintenance-failings-07-10-2019/
The University of Texas at Austin Civil, Architectural and Environmental Engineering (n.d). An engineer's perspective: protecting bridges from terrorist attacks. Retrieved from http://www.caee.utexas.edu/news/features/345-bridges
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