In the web article “I-5 and the Physics of Bridge Collapses”, Hartsfield (2013) claims that the concept behind a functional bridge design is what leads to its failure as well. Truss bridges “are composed of steel beams in the shape of triangles”. According to the article, triangles are used for truss bridges as its shape cannot distort without a beam or joint failure. It is observed by Hartsfield that corner and beam failures are the underlying causes for most truss bridges.
Suspension bridges are built by hanging huge cables from “tower to tower” with smaller ones hanging straight down and fix on the road deck at the side. However, the failure of suspension bridges is mainly due to its design as well because it is not designed to withstand huge external force. Hartsfield states that “when an external force causes the bridge to vibrate at its resonant frequency, it causes the vibration to grow stronger and stronger.” This means that the design of the suspension bridge is also the reason for its failure due to its incapability of withstanding huge external force.
Cantilever bridges have a small base with little to no intermediate supports. Hartsfield claimed that cantilever bridge design is governed by “just how much torque the lever arm can take”, and that its failures are generally due to construction oversight or overestimating the torque it can take.
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