A bridge too far?

We pride ourselves on the variety of vessels and projects we work on here at Amsterdam Yacht Service – from yachts to tourist boats to commercial vessels and workboats, they all come to take advantage of our in-water berthing, haul-out and hardstanding, refit sheds and inhouse expertise.

So when we got a call to assist with work on a bridge, it was just another standard AYS day – or so we thought. This bridge, it turned out, was not the bridge of a yacht, and not a vessel at all – it was a bridge, as in an actual bridge (or a part of one at least)!

The client, Dura Vermeer, is a leading Dutch construction and civil engineering company, and they wanted our help with a section of bridge for a major construction project they were undertaking in Amsterdam, building and placing parts of a new rail bridge section. The operation involves putting the new bridge sections on a pontoon which is then sunk almost completely underwater, floated underneath existing bridges to where it’s needed, then refloated for the bridge section to be craned off and dropped into place.

“What we actually did to assist Dura Vermeer sounds almost comically simple to say,” smiles Robert Binnekade, AYS’s managing director. “Basically, we took the bridge section off one pontoon and put it on another pontoon! But there’s more to it than that, because if you look at the steel construction of the bridge sections, they’re large and they are heavy – and they are also not always perfectly balanced in terms of weight distribution.”

It is here that a unique technical feature of AYS’s travel lift comes into its own – it’s capable of undertaking asymmetric hoists, negating the need to spend time trying to work out the centre of gravity of an object to be lifted. “Normal travel lifts have coupled lift points, meaning that the two sets are balanced and need to be balanced, which is fine for most applications and for most yards and marinas,” Binnekade explains. “But having the asymmetric lift capability means we can undertake more complex or imbalanced hoists with ease.”

The project also demonstrates Amsterdam Yacht Service’s rigorous approach to getting approvals for key operations. “Getting approval for the hoist plan was one of the biggest challenges, because even though it was perhaps the most straightforward lift plan we have ever made – lift the piece up, float in a new pontoon, lower the piece down – it involved six different companies and experts to look at it,” Binnekade explains. “We got it fully certified and signed off by an external inspection company. This is an operation intrinsic to a multi-billion contract with multiple contractors involved, and you don’t mess around when it comes to that sort of project! What’s more,” he concludes, “it gives me a great deal of satisfaction to know that AYS contributed in some small way to a bit of infrastructure in Amsterdam.”