Today in Dutch newspapers, Jan Pesie, the CEO and owner of the construction company who was responsible for the failed operation where two land cranes positioned on barges were supposed to install a bridge, acknowledge their mistakes and failure. In this project, a 187mt heavy bridge section was lifted by two hydraulic cranes, each positioned on a separate barge.
During the operation, one of the cranes tipped over and dragged the whole combination down, falling on several houses. Jan Pesie was quoted:” We don’t have the in-house expertise to perform and check the stability calculations and do the checking on the pontoons, we have failed”. Later on he was saying: ”This should be done better in any future projects and be outsourced to specialists.
Although, I don’t think that any specialized company could have been able to point out either where this went wrong on forehand”. Now I do think, as project manager of a specialized transport engineering company, that it is our job to actually do so. Companies are paying a lot of money for calculations they can’t do in-house and expect to be advised about the risk’s that they will take. Sometimes they even hire specialists as surveyor to check these calculations and the operation on site, just for making sure situations like this won’t happen.
Of course, we know that in most situations this doesn’t happen. Calculations are probably ok and a surveyor seems to be only there for the nice pictures. But don’t you expect that your car is running smooth after it went to the garage? Should you agree that if your wheel ran off your car because someone forgot to check the bolds, that they would say: “no other speciliast would have seen this coming”? SOURCE: Maritime Transport Engineering
If you would, what’s still the value of a specialist?
Comment of the Heavy Lift Specialist:
I completely agree on the above comment made by : Maritime Transport Engineering
During the past two weeks I have made an incident Analysis on basis of the YouTube Video and the pictures and data, I have collected from the Internet. Based on conservative measurements, I can only conclude that the GM value of the aft Barge with on top the Liebherr LTM1400-7.1 crane was somewhere between the 1.5 and 2.0 m, which is considered relatively low for such a complex operation.
The Contractors and the Municipality of Alphen aan den Rijn have highly under estimated the Stability of the barges and the very little margins under which this operation could have been carried out safely. Apparently they went over these very narrow margins, with the result we all know. It is a miracle that no one got hurt or killed in this incident. Hopefully the Industry realizes that lifting a heavy load with hydraulic cranes positioned on floating barges requires more then just a say: “We can do it, no problem”! From the Marine side, I received support from Dutch Offshore Innovators B.V. and Seacamel B.V.
As my Analysis is only based on conservative estimates, I would very much welcome an official report based on the actual data during the incident, so that we all learn from the mistakes made here!
Presently The municipality of Alphen aan den Rijn, has invited 5 parties: Smit Tak (part of BosKalis), Mammoet, Hebo, ALE Heavy Lift and Sarens to submit a salvage plan.
Als het mee zit, is het brugdek nog voor de jaarwisseling in de Koningin Julianabrug in Alphen aan den Rijn gehesen. Dat zegt Jan Pesie, directeur van BSB Staalbouw, in een interview met Studio Alphen.