Expert assembly of prefabricated elements

Ever since 2021, Contracting and Rental Company has been providing Slob Noordeloos commissioned by construction consortium De Groene Boog to assemble a wide variety of precast elements on and around the A16 Rotterdam motorway. From noise barriers and edge elements to abutments and the heat protection in the tunnel construction. And all completely self-supporting with qualified professionals and our own equipment. For the viaduct over the Hoofdweg (KW58), the Arkel-based company is again providing a number of crucial services.

Experience by simply doing it and being transparent to the customer is how we can now describe our way of working, says Jonathan Brouwer of Slob Noordeloos Contracting and Rental Company. "Involving our expertise at the front end can help clients make the right choices in the application of fastening systems, for example, or underlaying precast elements with various types of mortar. We are also at home in the field of logistics. We were able to apply many of our specialties to the A16 Rotterdam. And still are, by the way, because in the coming period we will also be involved in the construction of KW58."

Noise barriers from A to Z

Slob Noordeloos started assembling the noise barriers along the A16 Rotterdam motorway in late 2021. "To do this, we first made the concrete prop foundations with anchor patterns in various sizes on the tubular piles. The different anchor patterns were all cut from one mold," Jonathan explains. "After pouring the concrete prop, the steel uprights were placed on these and set in the X, Y and Z directions. These are then underlaid on the structures with a special Tikso mortar and the uprights on the tubular piles are cast on with a pouring mortar using our forced-mix pump. In this way, leaks on underlying road or rail networks are prevented. De Groene Boog then backfilled the posts to verge level so that we could proceed with the final assembly of the angle lines. And - depending on the location - an infill with sound-absorbing Durison elements, glass panels of various sizes, whether or not in combination with a concrete plinth." In total, Slob Noordeloos poured some 1,256 concrete props, assembled 2,851 A-frames and posts, installed 3,214 wood fiber concrete panels and 2,578 glass panels for the total of 9,122 linear meters of noise barriers on the A16 Rotterdam.

Diamond pattern in suction cup

After assembling the noise barriers, Slob Noordeloos started assembling all the edge elements on the structures and the embankment slabs under the structures in 2022. "The edge elements are suspended from two angle lines that we anchored into the deck," says Jonathan. "We used our own telescopic handlers and tools for this. De Groene Boog then poured the ramps against these themselves. To install the embankment slabs, we used our vacuum system that was specifically adapted for this project. We had the diamond pattern of the embankment slabs cut into the rubber profile of our suction cup so that we could immediately pick up and install the slabs at the correct angle. That is also where our strength lies: responding to changing requirements or needs each time, and applying the most efficient way of working. In total, we installed 650 edge elements and 950 talus slabs."     

Comprehensive range of attachments

And speaking of special tools, Slob Noordeloos also developed a special frame for mounting the 110 pieces of pre-walls. "The first series of pre-walls was mounted by us in 2021 under the artwork across the A13" Jonathan looks back. "The walls are set back several degrees. We drove them under the artwork with a special forklift frame and lowered them with ratchet hoists at the front of the frame, so that we could mount them directly at the correct angle. Allen bolts were then used to secure the pre-walls through the joints. An intensive job, since the pre-walls range in weight from 1.5 tons to as much as 8.5 tons. But as mentioned, we have a whole range of tilt and placement frames to maneuver and assemble panels and elements at all possible angles. Even under height-limiting situations. And if we don't have it yet, we'll make sure it gets there."

KW58

The construction of the A16 Rotterdam has now entered the final phase with the final piece being the construction of the new viaduct KW58 over the Hoofdweg. "We are also making an important contribution to this," says Jonathan. "In order to keep up the pace of construction, the artwork will be largely prefabricated. All those precast elements will be assembled by us, except for the girders. The work is divided into four assembly phases, during which we will install a total of 23 columns, 7 U-beams and 28 precast elements for the abutments in varying sizes and weights of up to 53 tons! In cooperation with crane rental company Sarens, we will ensure professional assembly. We will also apply the setting mortar and underlay the casting mortar in various compositions with our forced mix pump. A major advantage of this pump is that the mortar is automatically produced in the correct thickness and composition. In this way we guarantee constant quality. In phases, we will remain active at the A16 Rotterdam for the time being and it is possible that something else will come our way in between."

An important part of our work is making safe choices, Jonathan says. "Experienced people are a factor in this. Because ensuring safety on paper is necessary, but awareness of working safely in practice is a must. That is why we are constantly working to provide our materials with certifications and looking for working methods to minimize risks. We like to take the total package off the customer's hands, so that we can keep a grip on inventories, logistics and efficient execution of the job. And we do this not only for the A16 Rotterdam, but also for many other infrastructure projects, such as for BAAK for the A24 Blankenburg connection and for Veenix for the widening of the A9."