- #36
radou
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cyrusabdollahi said:Excuse me, I am going to go hide in my closet now with my duct tape.
Short off-topic comment: at some point, you'll have to get out of the closet, though. :tongue:
cyrusabdollahi said:Excuse me, I am going to go hide in my closet now with my duct tape.
Yeah, and of course, parts of the roads never detatched, so those sections only fell at one end. So perhaps the outer third on each side was slowed by that. But the center of the span would have fallen at near freefall acceleration. Also, though, supporting a falling object from one side makes half of it fall slower than g, but the other half faster than g because the center of gravity is trying to accelerate at g. That's why smokestacks that are demolished by toppling them break while they are falling - the different accelerations cause them to bend.Mallignamius said:Isn't there any resistance from the connecting roads? I was just wondering if it would take slightly longer to begin a drop because of the steel beams (or stiffening girders?) running horizontally underneath, connected to the ends of the bridge and the anchorage blocks or abutments. If so, perhaps that would explain the "earthquake" descriptions, that the bridge has to pull away from the ends?
cyrusabdollahi said:I like how the newspeople are asking, "well, they were jackhammering near the bridge, do you think that might have been a cause?"
cyrusabdollahi said:A jackhammer is not really going to put a stead sinusoidal vibration on the bridge at exactly the resonant frequency of the structure.
cyrusabdollahi said:Interesting, you think jackhammers would have an effect on such a large structure? Personally, I find it rather hard to believe. I would expect the vibrations of the cars and tractors trailer going up and down the bridge to wash out the noise from a jack hammer.