Versatile specialist in steel auxiliary structures packs solid punch at Selective Withdrawal

Since the summer of 2022, Marsé Montage has been working almost continuously on the Selective Withdrawal at the sea lock in IJmuiden. Among other things, all the outrigger frames, the anchoring constructions and the purlin work come from the quiver of the specialist in steel auxiliary constructions. Even the renovation of pile heads can be safely left to Marsé Montage, as is evident here at the lock complex.

Marsé Montage is a regular partner for many civil engineering companies in our country. So too for Van Hattum and Blankevoort, which is responsible as the main contractor for the construction of the Selective Withdrawal. "The work we perform on this project is extremely diverse," begins Job Hester, director-owner of Marsé Montage. "For example, we are closely involved in 'moving' 23 existing mooring posts from the north to the south side. We burned off the head of the old posts and made them like new again in our workshop. Damage and dents were repaired, new pieces were welded in where necessary, and finally the heads were re-coated. We then welded the reconditioned, fresh pile heads onto the newly installed mooring posts on the south side of the lock complex. A handsome piece of reuse."

Custom anchor and follower plates 

To build the Selective Withdrawal, many hundreds of tubular steel piles were installed. For this, Marsé Montage produced the anchor and follower plates in different sizes and angles, and in thicknesses ranging from 50 to 90 mm, to anchor the piles. "Using these plates, the anchors are tensioned off," Job explains. "In total, we produced 247 pieces of anchor plates and about 508 follower plates that are milled at the same angle at which the anchor goes into the ground. So each anchor also has its own follower plate, which in turn lies (in pairs) on the anchor plate and are secured with a tension nut. Despite the large quantities, it may look like mass production, but it is anything but. Each anchor and follower plate is different."

Sturdy steel frames

Marsé Montage is also handling all the purlin work at the Selective Withdrawal. "A number of sheet pile walls needed purlins. We not only produced these but also assembled them. Furthermore, we provide all kinds of hand and hand services on an ongoing basis. For example, we also burned off all sheet piling and tubular piles and are currently welding cuttings in the fish passage. This is where the concrete sloof will rest. We are also going to construct various reinforcement frames for the abutments on both sides to hold the piers in position. The frames consist of steel HEM beams 600, 400 and 350 mm in combination with sheet metal. It's quite a complex job because the frame allows little margin and it has to take place at 10 meters below NAP," acknowledges Job. "But again, in close cooperation with our client, we will undoubtedly bring this to a successful conclusion."

For Marsé Montage, the project is a great reference. "We have been working on it almost continuously since last summer and are our client's 'right hand' so to speak when it comes to the steel auxiliary structures. We like to think along and know better than anyone what is going on at the interface between land and water. We recently received an additional order for the production, installation and welding of two mooring posts at Zuidersluiseiland. The piles will be drilled and fitted with new pile heads that we will set and weld." Job expects to be active on the project at least until March 2024, unless they also score the last orders then a little longer. To be continued, no doubt!