Asphaling and machine paving under a slope

Reinforcing a dike often requires the use of specialist equipment and, above all, expertise. Soon after its foundation in 1986, Boot G.W.W.B.V. began to specialize in dyke reinforcement. Many an infrastructure contractor knows where to find the Brabant-based company to carry out specialist tasks, such as asphalting and mechanical paving under a slope. Boot G.W.W. was also active on the Afsluitdijk for several years and since last year has been involved in the dyke reinforcement Lauwersmeerdijk - Vierhuizergat on behalf of Combinatie Waddenkwartier. 

In 2019, Boot G.W.W. started work on the Friesian section of the Lauwersmeerdijk. Initially it was planned that the company would deal with the installation of the asphalt on the dike, but since there are also sett stones on this dike, the assignment was soon expanded. "With thirty years of experience in reinforcing dikes in Zeeland in particular, for the last five years we have been particularly active in the middle and north of our country," says Richard Verheyen, director of Boot G.W.W. "For example, we are also currently working for Heijmans, GMB and DEME on the dike reinforcement between Gorinchem and Waardenburg, and since 2023 here on the Lauwersmeerdijk. By the way, the work on the dike itself takes place outside the storm season, from April to October."

Precision work

Boot G.W.W. specializes, among other things, in the machine application of asphalt at an incline. "It really is precision work and comes very close. The more accurately the layer thickness is achieved, the better and the less material you actually 'waste,'" Richard rightly states. "In this case, over a stretch of about 8 kilometers, we are applying a 15-centimeter thin layer of asphalt 10 meters wide on the embankment slope." The asphalt is brought in by truck, tipped onto a driving slab, then Boot G.W.W. specialists apply and smooth it onto the embankment with a longreach excavator. "Using GPS equipment in our crane, we keep a close eye on the thickness. Incidentally, we also neatly level the lower course ourselves first, before covering the top layer with asphalt."

Machine paving

After Boot G.W.W. had well and truly started asphalting the Lauwersmeerdijk on the Frisian side in 2020, an additional request came from Heijmans to also take care of placing the Verkalit blocks. Founder Kees Boot has developed his own clamps to place different types of blocks (setting stones) on dikes. "We have been doing that successfully for many years throughout the Netherlands, Belgium and Germany," says Richard. "And now also on the Lauwersmeer dike. We do the installation with two longreach excavators with GPS machine control, using one machine to make the bed in the same way as for the asphalt, but consisting of a layer of Norwegian granite with geotextile underneath. With the other machine, equipped with a special attachment, we lay a series of Verkalit blocks neatly in place against the concrete retaining strip at the toe of the dike in one motion. And where the blocks stop, we apply the asphalt at a later stage. And so the work follows one another."

Machine paving and asphalting can only be done outside the storm season, but even during the storm season, Combinatie Waddenkwartier Boot G.W.W. manages to keep busy with all kinds of work. The old pavers will be reused as a rattle strip in the new, narrowed Defense Road on the inside of the dike. "We've developed our own clamp to do that by machine as well, and so we can just put that back in during the storm season." Richard expects Boot G.W.W. to be active on the project for one more season.