Ground beneath crane gives way - GIF

Ground beneath crane gives way.

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Previously:

https://www.homemadetools.net/forum/...983#post202866
https://www.homemadetools.net/forum/...425#post200581
https://www.homemadetools.net/forum/...903#post198685
https://www.homemadetools.net/forum/...962#post198794
https://www.homemadetools.net/forum/...480#post196963
https://www.homemadetools.net/forum/...879#post194480

That suddenly got real expensive, and it wasn't from lack of trying to properly pad the support legs

What did the Geo surveyor have to say?

Quote:

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Originally Posted by NortonDommi

What did the Geo surveyor have to say?

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If one had been called for his site analysis. He would have referred them to a civil engineering contractor who would have excavated the proposed crane pad site, then driven piles into the ground on the downside of the slope to create a stabilizing barrier, back filled with rip rap and crushed stone mixed with select fill, compacted this to 125%, then the crane could have been brought in. Expensive but often worth the cost when the strata under the surface is unknown especially on a slope or near a body of water.
You can tell there was some concern about the pad area by the way the blue hard hat was keeping an eye on it. It looked like they had decided to abort the lift and was bringing the beam section in as close as possible to set it down

At about 3seconds in, they were talking about something "breakin away". Seems they should have stopped and reset at that point.

Although it may not have been a factor in this situation, the load swinging changes the dynamics of the weight on the crane.

Blue hard hat at 0:16 was looking under the wheels of the crane at the large cracks that had formed. Should have aborted then if they could.

Quote:

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Originally Posted by Hoosiersmoker

Blue hard hat at 0:16 was looking under the wheels of the crane at the large cracks that had formed. Should have aborted then if they could.

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It looks like they were already being well beyond the abort the lift stage by that time. From there on out it was hope and prayers they could get the load on the ground before something happened. Didn't quite make it though.

I reckon it was taking a gamble in the hope of saving a few bucks. That is a tidal river and looking at that soil not good. Mats or not Mangroves, mud and shell banks do not good footing make. Hard to believe anyone with experience would have attempted that lift.