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Name: zuni
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993


Question:
During the San Francisco Earthquake the Oakland Bay Bridge fell. Why did not the Golden Gate Bridge fall?



Replies:
The Golden Gate bridge and the Oakland Bay Bridge differ in construction, in that the Golden Gate bridge is a suspension bridge, and the Oakland Bay Bridge is a series of individually supported spans. The earthquake in SF actually changed the locations of the footings of the Bay Bridge enough to change the length of the spans. As the distance increased between each span, the center sections fell down. On the other hand, the Golden Gate, being a suspension bridge, has no real solid relationship between the bridge span and the footings in the channel. The footings can move a considerable distance, and the worst that would happen is that the suspension cables would change tension. In that way, a suspension bridge is far superior to a conventional span. On the down side, however, suspension bridges have an annoying tendency to break into harmonic resonances with the right vibrational input. One bridge, a long time ago, broke into oscillation and actually fell after a dog trotted across it at a constant rate. Do not worry though, all suspension bridges now are built using enough different materials to prevent things like that from happening.

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in another small container called, you guessed it, the absorber. From there this concentrated solution flows back to the generator to complete the cycle. This is the type of refrigerator that is seen most often in campers and RV's.