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Crane collapse in Austin, TX

I can't understand why the shedding of the load caused the crane to fall over
like it was overloaded.

Unless there are (2) different problems going on here.

When the shackle broke (or the insert pulled out, or what ever broke) the
load fell to the ground.
 
I can't understand why the shedding of the load caused the crane to fall over
like it was overloaded.


Unless there are (2) different problems going on here.

When the shackle broke (or the insert pulled out, or what ever broke) the
load fell to the ground.
K=1/2mv^2. It doesn't take a lot of velocity to generate a whole lot of force and when that rigging failed that panel was nearly in free fall for a few feet.

To me it looked like the crane itself was fine and that an outrigger itself failed or it's footing subsided.
 
K=1/2mv^2. It doesn't take a lot of velocity to generate a whole lot of force and when that rigging failed that panel was nearly in free fall for a few feet.

To me it looked like the crane itself was fine and that an outrigger itself failed or it's footing subsided.

I see, what your saying is the load dropped, then the rest of the rigging
"Caught it".

I agree that would cause the over load.

Note how the crane is "following" the load as it hinges up, and the crane
continues in the same "swing" direction after the overload.

Could be the operator was really getting on the swing, either to "catch it"
or was still in "normal mode" and was in a hurry.
 
Hello Cole2534
Guy in yellow that was actually standing on the base of the slab when she let go got the scare of his life.:eek: Lucky to be alive. Probably had to wipe himself after that.;)
 
Looks to me, that when the cable or fitting failed, it momentarily unloaded the spreader, then hit it with all the load again. That was probably enough of a bounce to simply tip the crane over.
 
Looks to me, that when the cable or fitting failed, it momentarily unloaded the spreader, then hit it with all the load again. That was probably enough of a bounce to simply tip the crane over.

Agreed. It was a tilt-wall panel they were erecting, so I imagine that spreader has sheaves on it to allow the panel to rotate up.
 
Southeast Austin is black gumbo clay ground, my old shop was not too far from there. More than a few times we would be in the middle of moving something with the crane and the outrigger pads would just start sinking under the pressure. I was the operator one day when the crane damn near ended up on its side, nothing scarier than watching all your rigging sliding of the deck as you walk onto the glass of the cab:eek:
 
Looks to me that rather than lifting clear to rotate the slab around its horizontal axis, the operator was trying to speed thngs up by using the swing to upright the slab, at the same time. This would put a side load on the boom that would be hard to calculate. Possible that this did something to the outriggers or cribbing that predisposed the whole crane to tip.

It does not look to me that the jerk when remaining slings caught the slab should have been enough to tip the whole crane, unless the whole pick was 'way too close to capacity. Dalmatiangirl may be on the right track

I wonder how lifting inserts are designed or qualified. I would suppose that they would have to be welded into the reinforcing. I would not trust a simple Lewis for multidirectional load in a thin slab.
 
Hello Cole2534
Guy in yellow that was actually standing on the base of the slab when she let go got the scare of his life.:eek: Lucky to be alive. Probably had to wipe himself after that.;)


Must not have much experience cutting farwood. Not learned to step aside from a falling tree as opposed to trying to outrun it.


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Think Snow Eh!
Ox
 
The article is of kind annoying, saying that using a crawler is inherently unsafe over a tower crane.

Never mind the fact that those tilt up panels aren't exactly light, and a tower crane would have to set them all from spot, meaning HUGE load radii.

+1 for rigging failing and the impact loading on the crane causing the crawler to tip over.
 
We have many new tilt-wall buildings here due to the UPS air hub and two busy Ford plants. Every one of them has been set with Manitowoc 3000 class cranes. I doubt a single tower crane could reach more than a few panels... This style building is built for lots of area on a single floor. Tower cranes are more useful for smaller footprints and many stories where the max loads are much smaller.

 
A tower crane wouldn't work well at all standing up panels.

Rigging attachments pulling out of panels used to be fairly common, not so much in recent years. The rigging failure was more than likely due to the people that poured the panel and set the lifting attachment points.

I've seen one and heard of many more instances of rigging attachments pulling out of panels. All the ones I've heard of, the panel just falls and breaks into pieces. I can't see what actually causes the crane to turn over. I have seen instances where the crane will turn over backwards (or at least flip the boom over backwards) when the load is released from the boom rapidly. It's due to the boom "whipping" back when the load is released suddenly.

If the operator did boom down, instead of hoisting down, that was a pretty stupid thing to do. There is also way too many people around the load, and the one guy was actually standing on the end. I bet the parties involved really didn't plan for this video to get out.
 
Must not have much experience cutting farwood. Not learned to step aside from a falling tree as opposed to trying to outrun it.


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Think Snow Eh!
Ox

+1, and clearing the surrounding area of brush beforehand with said chainsaw.....:crazy:
 
The crane has way too much boom for panels.It looks like a 100ton crawler to me,and I think either a trackframe has broken,unlikely,or the ground has collapsed under it.A crawler normally pivots over the track ,and that one doesnt do that,the side just collapses......still he has way too much boom for panels.........panel rigging is set by a concrete laborer at the factory,generally a young guy who cant read,write ,or stay off ice.....So would you trust the lifting points?...Seen theb break out of kerbstones,let alone a 20 ton panel.
 
I think either a trackframe has broken,unlikely,or the ground has collapsed under it.A crawler normally pivots over the track ,and that one doesnt do that,the side just collapses......

That is how black clay acts, surface can be hard as stone, 2' down its mush. The day I almost flipped crane the ground was dry, drove 20T crane into position, loaded semi pulled in alongside. Last (heaviest) piece was a pipe bender that was pushing 20 tons, initial lift was fine, then as truck pulled away the ground under outriggers started giving way, we had to use backhoe to retrieve outrigger pads, they were 3' in the ground.
 
When youre moving a crawler,if the tracks arent sinking in,you assume the ground will be good for work......but I still think if he had a sensible boom length he would have recovered easily....the worst fright I ever had was a crane barge turning over,I was lucky not to drown.Years ago I saw a operator ride an old dragline down a slope into the river..he was still holding the levers when they pulled the crane out of the river with a D9...open cab,he just had to let go.
 
The crane has way too much boom for panels.It looks like a 100ton crawler to me,and I think either a trackframe has broken,unlikely,or the ground has collapsed under it.A crawler normally pivots over the track ,and that one doesnt do that,the side just collapses......still he has way too much boom for panels.........panel rigging is set by a concrete laborer at the factory,generally a young guy who cant read,write ,or stay off ice.....So would you trust the lifting points?...Seen theb break out of kerbstones,let alone a 20 ton panel.

Hello John.k
Truck crane.

Scroll down the page to watch the other 2 videos.
 








 
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