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Crane collapse in seattle

Knepptune

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Nov 22, 2012
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757
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Indiana
Just saw this a minute ago. A little bit of a reality check on the dangers of tower cranes. Looks like the crane was being being dissembled when the mast broke. I’m sure more will come out but four people dieing is a tragedy.

It’s really easy to get to get to comfortable and complacent when you do that kinda thing regularly. It’s just a reminder that at those heights, you typically don’t get to make two mistakes. Your first one can easily be your only one.


https://www.google.com/amp/s/www.ki...ntId=281-a09a8074-0e42-43bd-bce3-85c52781b844
 

hvy 1ton

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Lawrence, KS
North-facing picture of the collapsed tower crane I found
1556418931191-png.739679


Satellite image of the building site with the partially built tower crane from a few months ago.
upload_2019-4-27_22-31-12.png
 

Natman

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Dec 19, 2016
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ID
It's been scary windy here in SE Idaho the last 3 days, very high winds aloft, I was flying in them while it was still calmer on the ground. Seems like as the day goes on the wind level lowers, something to do with the barometric pressure changes as the day goes on. But I know at least in my area, it is somewhat common to have no wind at ground level, but got up a couple thousand feet, and you have wind, and when that happens and I land and it's calm again down low, I plan on it getting windy before noon. Obviously, wind had something to do with this accident, the gustiness of this cold pressure system moving thru probably had something to do with it.
 

John C.

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Right now only the news media has said anything about wind and some reports state wind was likely not a factor. One report mentioned the crane was being taken down. It will be awhile before the public gets to know much. Last one was months of speculation until some safety agency declared it to be a manufacturer's defect. In my mind, someone seriously screwed up.
 

Ronsii

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Western Washington
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s/e Heavy equipment operator
So it was in the removal phase.... I heard a guy on the radio this morning saying how he had seen the site and everything was on the ground indicating failure before any removal.... so I'm guessing it fell right on the parts of the crane that were already removed...
 

Knocker of rock

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Jun 10, 2012
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US Western Cordilleran seismic zone
So it was in the removal phase.... I heard a guy on the radio this morning saying how he had seen the site and everything was on the ground indicating failure before any removal.... so I'm guessing it fell right on the parts of the crane that were already removed...

What you heard had to have been wrong. The photos don't show either the front or rear booms, the drums or the CW landing points. So what failed was a bare tower and house.
 

Ronsii

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Yeah, I know.... this is just what a guy that was working near the site said he had seen... but he either misguessed or doesn't have a clue... although he talks like he does ;)

Yes, seems weird that just the tower with no booms could have failed... even with winds off the chart! so who knows what happened... I'm sure more videos of it will surface sooner or later and offer clues as to what happened.
 

Knocker of rock

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Jun 10, 2012
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US Western Cordilleran seismic zone
The load out, tower base and mobile crane all were on he north or east. The crane fell towards the south. My guess is that as they were handling the last boom piece the wind got it and it struck the tower hard enough to collapse a vertical chord.
 

John C.

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A video clip shows at least one man standing in the cab apparently handling lines from the picking crane. For some reason the picking crane pulled the lines away and swung violently to the west. There is another clip that was on the NBC affiliate last night that shows the tower falling. It is tipping from the base of the tower and all fell as a unit.

Just my thoughts at this point but I would have thought that each section of the tower would have be disconnect and lifted individually. In this case that piece of video shows what I would have thought would be removing the cab section and working down. Why it would have tipped at the base is the question.
 

hvy 1ton

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Lawrence, KS
The load out, tower base and mobile crane all were on he north or east. The crane fell towards the south. My guess is that as they were handling the last boom piece the wind got it and it struck the tower hard enough to collapse a vertical chord.

The mobile crane was on the north side of the building and the tower was setup inside the building footprint.
 

old-iron-habit

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It is not unusual to take them down with a assist rig taking multiple sections at a time. I would not be surprised if the crew had most of the bolts out before they got it rigged and it started to go before they got it hooked. Just speculation on my part but that has been the common theme recently on erecting and dismantling collapses. One went down a couple of years ago when jacking and they had unbolted the jacking section and started dropped it without re-bolting the head section to the tower first. 7 dead on that one.These are normally done on a weekend when the job is empty. It seems that the crews that do it for a living sometimes miss a step or final inspection before the next step, or get in a hurry and push things because they got by with it before. A tragedy and the dead workers and the innocent killed on the street have families left suffering and wanting in any event.
 
Last edited:

Tugger2

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Mar 22, 2018
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1,366
Location
British Columbia
Found this picture. Look at the areas where the sections join together. Everything has come apart cleanly, nothing torn out or bent.
Someone took the pins out too soon.

View attachment 195991
Its hard to imagine even considering removal of pins prior to rigging it ,but i have no familiarity with tower cranes and their dismantling procedures. Sorry to see lives lost.
 

Knepptune

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Messages
757
Location
Indiana
Those pictures of mast sections with no pins seem like a giveaway to me.

It’s not uncommon to go down and knock 4 pins out of each section. Each section typically has 8 pins. 2 on each mast cord. Not unusual to go down and knock 1 out of each cord once the jib and counterjib are off. Could have been a miscommunication. Send new guy down the tower to knock half the pins outta each section. “Hey knock those pins out on your way down” new guy heads down the tower not knowing they meant only knock half the pins out. I can’t imagine a seasoned guy being comfortable up on top of the tower with out it being pinned.

But I wasn’t there. I could be way wrong on what happened.

Definitely hit a little close to home for me. I’ll be nervous next time I’m up on one.
 

old-iron-habit

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Its hard to imagine even considering removal of pins prior to rigging it ,but i have no familiarity with tower cranes and their dismantling procedures. Sorry to see lives lost.

Unfortunately it has happened more often that it should. There are no second chances in that game. Our operators were required to check the tower pins on the way up and down each day as they climbed. Never ever heard an argument from them about it either.
 

Knocker of rock

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Its hard to imagine even considering removal of pins prior to rigging it ,but i have no familiarity with tower cranes and their dismantling procedures. Sorry to see lives lost.

I've been out of heavy construction for quite a while, but back about 25 to 40 years ago I could see almost every overly agro superintendent I knew getting all excited and ordering such work. But things change and I would have hoped that the ironworkers were specifically trained by Morrow to disassemble their cranes. If not, that is what I see in the immediate future, that the crews will have to go to training classes and be certified for each manufacturer and broad class of crane.
 
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