Seattle Crane Collapse
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Posted by David Schott (+13916) 6 months ago
Pretty stunning.

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Posted by MilesCity.com Webmaster (+9611) 6 months ago
Reply to David Schott (#378109)
Oh man, that's bad. : (
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Posted by Dave Roberts (+1236) 6 months ago
Looks like somebody pulled all the pins
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Posted by Amorette Allison (+9732) 6 months ago
Horrifying might be a better word!
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Posted by Dave Roberts (+1236) 28 days ago
Yup, pulled the pins early.

https://komonews.com/news...ned-107000

What I don't get is why the crane owner, who didn't assemble or dis-assemble the crane, got fined so much more than the guys who prematurely pulled the pins?

New Orleans and their nearly perfect Yard Dart landing https://twitter.com/payto...9715591170 got me thinking about this again

That is probably more than 100' and 25,000+ lbs of collateral damage flopping across the boulevard in NOLA

[Edited by Dave Roberts (10/20/2019 7:25:26 PM)]
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Posted by David Schott (+13916) 28 days ago
That crane job in New Orleans today didn't appear to go as planned. It looks like the counterweight of the one crane is now hanging precariously from the top of the tower and the boom is also barely hanging. From bad to worse.

From what I read about that Seattle crane it's standard operating procedure to remove the pins as you work your way up to the top when dismantling them. That is very much against the manufacturer's recommendation and yet it is apparently "done all the time".

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Posted by Dave Roberts (+1236) 28 days ago
Even as big as they are, high-rise tower cranes are still fulcrums and they should keep that in mind assembling or dismantling. If you pull all the pins on the way up, the first pin you pull moves the pivot point to the previous pin or anchor point

I know that in L.A. recently, the 3 small tower cranes we had attached to the structure, 9 stories up, needed 22,000#+ of counterweight to hold up 3,000# at 80' boom length and had a very specific order of installation and removal

In NOLA, they should've blasted the counterweights & booms loose before anything involving the towers (tower tops are the pivot points)
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Posted by David Schott (+13916) 28 days ago
Reply to Dave Roberts (#378655)
In the case of that Seattle crane that tipped over the jib and counter jib had already been removed. I assume they don't ever pull the pins in the tower sections until the jib is removed, but it seems that the workers felt that it was reasonably safe to start removing the tower pins once the jib was off.

The manufacturer's instructions say that the tower pins aren't to be removed from any section other than the one that is currently being removed and only after that section has been rigged to the mobile crane that is taking down the tower crane. That's kind of a "No duh," thing if you ask me.

20/20 hindsight, though.
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