A friend in Australia sent me this,I will recreate the email the best that I can. ----- Original Message ----- Subject: Fw: 250t Liebherr Accident There’s a valuable lesson in here men in regard to the importance of always ensuring appropriate engineering input into satisfactory load dispersion when establishing mobile cranes. As per the attached photo’s, this was a nasty incident on a project out at Castle Hill last Friday. As we’re all aware, “thorough investigation into load dispersion and back-propping requirements is vital when establishing a mobile crane unit on a suspended slab to eliminate any potential for failure of the supporting deck.” Incident: Friday Morning 26/09/08 – Castle Hill/Sydney Australia - 9 Day Old 250t Leibherr Crane (never used before) - $4mill price tag - Failure of back propping beneath the 200mm thick concrete deck - Crane support outrigger punches through slab causing crane to lose balance and collapse across the site and onto adjoining property - Crane balanced in the air for approx 1 hour before entire rig & boom collapse completely across site and rigs falls through to the basement level. Amazing that no-one was seriously injured or killed. -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.169 / Virus Database: 270.7.6/1713 - Release Date: 10/7/2008 6:40 PM
Last two pics What a shame,huh?Ron G
Opps Glad Noone Was Hurt
Who thought it would be a good idea to put that crane on a concrete deck like that? Never in a million years would I put a crane of that size on a fresh deck like that. Maybe a small rough terrain, but not a large truck crane. Someone was not thinking that day.
on the bright side, good time to grease the undercarriage
Could not agree with you more landrvrnut22, there is something called a process before setup. A company rep, and with a 4 mill crane being used a (competent rep) would first go step by step with the customer over the entire pre-lift sequence.That is a complete shame and will only hurt the industry with these accidents piling up. Whomever it was that allowed that crane to set up at that site has got to be looking for work today!
Well they say a picture says a thousand words and this is the facts. 1.This was the 5 th trip to site to do this job . 2.26 of the panels had been stood up in the previous 5 trips. 3.There was only 6 to go. 4.The whole job was palnned by an engineer who had marked on the slab an x to show the placement of the crane. 5.The builder was responsible for propping the slab .As they were in the 5 previous visits. 6.This lift plans and safe work method statements had been approved by the engineers(probably thre same ones who marked x)and the builder. 7.The crane crew were doing as they had done on 5 previous trips except they had a new crane. Gillespies is a fine family buisiness with a fleet of cranes and a reputation that is envied by the crane world.The owner is tall poppy in the industry and other like to chop the tall poppy but they are a biy jealous of the reputation thy enjoy and probably the rates they get forthe crane hire.
I have a couple of questions The bracing underneath deck was not done at all ? - or not done properly? Was this a bigger crane ? longer reach ?
it appears the bracing may not have been up to scratch.This was a bigger crane with the other trips to site done with a 225 tonner and this is a 250 tonner ebut the wortk method was changed to suit and the x on the concrete to show the crane crew where to set up was adjusted accordingly.
Man that is a shame indeed, I think if it had been my job I would have checked behind the folks that were in charge of the braceing. I'll bet you couldn't find a gage that would measure the amount of PUCKER (pucker factor) in this case. Scratch the statement of checking behind the workers, I went back & saw the braces now to figure what went wrong.
They pulled it out last Sat with a 400 tonner and a 225 tonner.Both up on the slab. On a site next door to that there is another 200 tonner up on a supended floor lifting panels as this one was.
If I were Investigating this I would be looking at and asking these questions; A - Did the marking on top line up with the bracing underneath ? B - I do not see any type of load bearing plate on top of the bracing in your picture C-Should the crane have had extra pads under the stabilizers ? (have seen stab. poke through hot top on city streets when lg. pads were not used to lessen the PSI) D -were they reaching out further putting a heavier load on the crane ( Ft X WT ) Do you know if they will try Repair crane? Try to salvage usable parts ? Or will it be a total loss ?
Check out the second pic down on the left. I see the X and the stabilizer sure isn't on it...
I worked with a operator on a 250t crane my first two years in this business and I've seen some hairy situations but I wouldn't be caught dead on a parking deck especially without something to distribute the weight or major support structure under it ointhead
Still need outrigger mats URGENT! I missed these the first time around and just got shown the link All I had was the pictures and spotted straight away that I would have expected mats to spread the load as much as possible. Having read through the posts, I wonder having changed the crane and changed the marks due to different footprint, did the propping get changed. The immediate assumption must be no! Does familiarity breed contempt :beatsme we've been here done it 5 times already, da, de, da, Oooops! Thats maybe unfair,.................. but somebody sure stuffed up! BIG TIME ! I cant prove the first picture was taken upon delivery and it doesnt make any difference really, but the photo file records it as taken 26/8/08 exactly one month earlier but with a different camera, which might have its date record wrong. Confused myself now, OZ and UK dates *ss backward to USA or vis versa depending on which lump of rock your standing on. Accident happened in Sept by pic file record.
If you look at my original post the date of the accident was 26/9/08.That would be September 26 '08 I would assume.I got email from a friend in Australia with those pics telling me about it.I made my post here on 10/8/08 the day after I got the email as I remember which is October 8 2008 in this country. There is a thread in Classic Machinery with the same pics from a citizen of Australia with several replies.Ron G
:lmao :lmao :dizzy No problem Ron, its as clear as day now, cant figure out how I got confused seemed to me you posted almost a month before it happened :drinkup Dont worry mate I'm only jangling your chain
i heard or read that it was on a thin layer of concrete thta wasnt supportep propley
I am no expert when it comes to cranes but I reckon the problem was the way the truck was positioned. Judging by the position of the crane all the load would have been on one outrigger and thus all the weight would have been placed on a small section of concrete. Perhaps some of the people that actually know a bit could chime in.
If I realized that there was already a thread on this horrific accident, I would have not wasted my time and re-posted it. Like I said in the thread that I started with this accident, a buddy of mine has e-mailed me the photos and story on it and I took it that it was recent. Sorry!
Won't comment on cause but affect is that the crane is totalled. Once the frame is shocked I know of no engineer that would sign off on safe operation of the rebuilt unit. Insurance adjuster will have a devil of a time figuring depreciation.
Stupid question from a wannabe crane operator (I wanna be a crane operator, but so far have been stuck operating everything else but cranes... ). After the first outrigger punched through, could the boom have been lowered to stabilize the crane? I have gotten many machines in unstable positions over the years (I have usually been working for lower-class companies where it was up to me to figure out how to work a machine safely. Then I discovered proper training and OSHA rules, and the bosses started not liking me as much!), and my normal response is to use the movement available to me to put the machine into a safe condition. I have seen many pictures of tipped cranes where booming down would seem to allow the base to resume a gravitationally harmonious repose. I know in some situations as the base came close to level, it would have enough leverage to outweigh the boom/load causing an unpleasant dynamic return to level-ish through lifting the boom or utilizing the mid-boom knuckle-joint. Other times, such as this, it would seem that booming down would have helped level the base and reduced the chance it would have broken the rest of the way through. Am I thinking right, or is it a good thing I don't work very close to cranes very often? "It is better to keep your mouth shut and appear stupid than to open it and remove all doubt" (Mark Twain) is something I don't agree with! "Better to open your mouth and appear stupid that to keep it closed and remain secretly stupid" (Ben Blackburn) :duh And for your viewing pleasure, a XcraneX Boom truck tipover from a recent-ish news video. They said it was due to unstable ground...
There are so many variables it cannot be presumed. Many cranes cannot be fully boomed out and lowered without counterweights fitted. Sometimes it might be better to lower the rope as lowering the boom will increase your radius, booming up may even be an option as well as retracting the boom
The easist way to cope with a situation like that is not to get yourself in a spot where you may end up being a passenger.. Its a tough break but by the photo I cant tell if it has a front jack..and the boom is clearly across the front quadrant..(though it is possable that the boom went through or sheared the spur gear/swing motor).. Ive run a few BT's where the rear jacks will float at 90% over the front simply because the truck chassis has so much flex..