Driven by craftsmanship

De Vries is a group of companies driven by craftsmanship that puts maximum effort into sustainability and safety. The three entities - De Vries Werkendam, De Vries Titan and De Vries Tensa - support each other where necessary and make grateful use of each other's knowledge and expertise. This often translates into efficient and innovative solutions.

De Vries Werkendam almost always realizes all kinds of hydraulic and civil engineering constructions such as bridges, locks, quay walls, sheet piling constructions, fendering and mooring facilities as a general contractor. To this end, the specialist relies on its own modern fleet of ships and cranes, some of which are emission-free. Last year, a new work vessel "De Ruigt" was added to the fleet with hybrid hydrogen-electric propulsion. "The vessel is basically all electric and is powered by stage VI generators that are also suitable for running on hydrogen. On deck is an electric telescopic crane powered by the ship's battery. This allows us to operate completely emission-free," said Paul Posthoorn, business manager of De Vries Tensa.

Maximum synergy

Unlike De Vries Werkendam, the other two divisions almost always operate as subcontracting specialists. De Vries Titan specializes in anchoring, while De Vries Tensa focuses on prestressing techniques. "We work for all contractors in the Netherlands and sometimes pull together," Paul continues. "In those projects, we create maximum synergy between people, equipment and results." Hendrik van de Woestijne, business manager of De Vries Titan, can also confirm this. "For example, we can make efficient use of each other's know-how, personnel and machinery. From De Vries Titan we are currently very busy on several large infrastructure projects, such as the widening and deepening of the A9 motorway, where we are drilling anchor piles to prevent the underwater concrete from floating up, we are collaborating on Groningen's new railway station and will soon start the large-scale bank replacement between Leimuiden and Alphen aan den Rijn. Here, together with De Vries Werkendam, we are going to install more than 800 anchors in the backyard of local residents. An intensive project, especially in terms of coordination and planning with all stakeholders. We are very strong in this as a group."

Powerful life extension artworks

Speaking of synergy, De Vries Tensa is also currently active on the A9. "Here, among other things, we are applying transverse prestressing to a structure," Paul explains and continues: "We are facing a major replacement and renovation task of artworks in the Netherlands. From De Vries Tensa we are lined up in this for, in particular, life extension maintenance of cable-stayed bridges. Last year, for example, we performed such maintenance on the Molenbrug in Kampen, an almost 200-meter-long cable-stayed bridge over the river IJssel. In addition, life extension maintenance can also include providing external prestressing. The current traffic intensity across a structure often no longer matches the initial calculations. By means of external prestressing you can reinforce existing civil engineering structures. A powerful method for life extension without having to add too much material. The method is relatively unknown in the Netherlands, but is frequently and successfully used in Germany and Austria. We use Tensa International's own systems.

And so De Vries group of companies puts maximum effort into sustainability and safety. De Vries is certified for step 4 on the Safety Culture Ladder and recently De Vries Tensa was awarded with a Safety Award for the safest subcontractor on the project 'Aanleg Middelseefaert' in Leeuwarden. Something De Vries is very proud of.