Final answer:
When shear force occurs unchecked on a bridge, it can lead to structural failure. Bridges are designed to withstand different types of forces, including shear forces, but if the shear forces exceed the bridge's capacity, it can lead to the collapse of the bridge. The Tacoma Narrows Bridge collapse in 1940 is an example of a bridge failing due to unchecked shear forces.
Step-by-step explanation:
When shear force occurs unchecked on a bridge, it can lead to structural failure. Shear force is a type of force that acts parallel to the surface of the material, causing it to slide or deform. Bridges are designed to withstand different types of forces, including shear forces, but if the shear forces exceed the bridge's capacity, it can lead to the collapse of the bridge.
For example, the Tacoma Narrows Bridge in Washington state collapsed in 1940 due to unchecked shear forces. Heavy crosswinds caused the bridge to oscillate at its resonant frequency, and as the support cables broke loose and slipped over the towers, the amplitude of the oscillations increased until the bridge failed.
It is crucial to consider shear forces and design bridges that can withstand them to ensure their structural integrity and prevent catastrophic failures.