Where did this happen?
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Where did this happen?
Wrong kind of fish but cute! Humor after tragedy is always good in my book!
Looks like the loader landed OK!! The guys on the wall probable have to change their pants!
Ralph
I am sure lots of "engineers" have spent hours if not years thinking about how to deal with a crane in a storm.
I would think they should drop the lift and anchor them to a immovable weight on the ground put tension on the cables and stress to the frame
to hold the crane in place.
Ralph
A question was asked about what should be the approach with securing tower cranes against damage from an incoming storm.
There are not a lot of options available. The video showing the erection of the Liebherr crane lasts less than 3 minutes - this represents an actual elapsed time of (I guess) 5 days or more. The erection or lowering of the main boom can take a day. Therefore dropping the boom is seldom a viable option. Also, free space is needed to lay the boom on the ground - both for erection and dismantling, and that free space is very quickly taken up by other activities on a construction site. The most common precautions have been mentioned - allow the mast to weathercock freely. Pray. There are very few athiests around when Mother Nature shows what She is capable of.
All heavy lifting is subject to pre-determined maximum wind speeds - you just have to trust that weather predictions are correct and that the wind doesn't freshen significantly. On a construction project I was involved with, we monitored weather at various remote sites up to 500 km away.
As a general statement, I gained tremendous respect for the amount of detailed planning and meticulous preparation that went into high and heavy lifting. I worked on the project for 7 years and in that time we "killed" 8 cranes, ranging from small rubber-tyred mobiles to a 400-ton lattice-boom tracked crane, and in most of those the sequence of failures started with a deviation from the original detailed plan. With that record of equipment damage we were extremely lucky to only injure 3 people. In the case of the 400-tonner there was the potential for multiple fatalities if it hadn't happened immediately after a meal break before the workforce returned.
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I think some of the ground crew didn't make it. @ 0:26 crane boom hits a panel to the right, previously erected. They have already started moving away, but tilt-up is 40' wide and maybe 80' high, right across their egress path.
Easy enough to find out. Jon, what is the link details for this one please?
Tilt ups are among the fastest and most economical forms of building construction for large cubic volume sized buildings. entire building structure is often nothing more than the concrete slab walls held together by carious methods at the vertical joints, most often being little more than a tongue and grove Ither times the very forms used to pour the slabs in are welded together Add a top cap to set the bar joist on and lay over the roofing materials Building is ready for electrical and mechanical.
Often not even the opening for doors windows or venting is considered until the building is almost complete or at least the walls are all standing with the cap rail in place. Openings are cut by concrete saws which climb the walls
But getting the tilt ups all standing and secured is the single most dangerous aspect of this type of construction. It appears to me that a combination of possibly 2 or even 3 factors were at play here the first insufficient counter weight the second if you will note the panel turned almost 90° to the crane as the crane was trying to move forward this suggests to me that the 2nd factor may have been a sudden gust of wind. causing it to turn. then the operator in trying to regain control lowered the panel. Once it touched the ground the already over centered center of gravity did the rest.
When picking these panels the tracks of the crane start out quite close to the edge of the panel with the point or crown or the boom almost never further out than two thirds past the center of the panel as the panel is raised the boom is raised as well to bring the center oc gravity as close to the crane body as possible. the crane would have backed up as the panel gets nearer to vertical to keep the bottom edge from sliding on the floor or ground which ever the case may be,
Once a panel is clear of the ground the only way to lay it back on the ground is to boom up and winch down bringing the bottom edge as close as possible tio the tracks again. There is one other way if the crane is equipped with a compensating counter weight that extends away from the crane not many cranes of this type are so equipped SO BOOM everything goes bad at once
TM51 mat be correct as there were a lot of ground crew in the vicinity while the panel was falling and possibly did not escape the second panel falling.
NOT GOOD! We had a local one a day or so ago & the crane fell on a house but no one was injured except the operators ego. It was just lifting a spa over the house and wind or poor experience /wet ground caused the accident.