October 6, 2025 | Published in Grond Weg Waterbouw, Issue 4, 2025

Knowledge and experience combined for the very first tram project with a ladder track system in Belgium

In September 2024, Taveirne, commissioned by De Lijn, began renewing the tram tracks in Bredene and Ostend. The project is remarkable because it marks the first time the innovative prefabricated ladder track system in a curved design has been applied in Belgium. For the production of this unique system, Taveirne partnered with De Bonte Group. Both experienced parties joined forces, pooled their expertise, and succeeded in delivering an impressive reference project. “From both a production and execution standpoint, this was a highly challenging project,” they say in unison.

Text by Niels Rouvrois • Images courtesy of De Bonte Group

Urban space is under pressure. The growing demand for mobility, the impact of climate change, and the need for livable public spaces make integrated solutions essential. It is precisely at the intersection of infrastructure and ecology that unexpected opportunities arise today. The areas along tram and railway lines prove to be particularly suitable for creating new connections — not only physically, but also in terms of sustainability, biodiversity, and climate adaptation. The green track, and more specifically the construction with prefabricated ladder elements, offers an innovative and robust solution.

INFRA-NATURE

Combining technical mobility infrastructure with natural elements has become a necessity. Green tracks are a tangible example of this, bringing life to the streets. Grass, sedum, or other low vegetation between tram rails not only contribute to a more pleasant streetscape but also fulfill a range of functions: noise reduction, water infiltration, air purification, and cooling. The result is infrastructure that softens the visual environment, delivers ecological benefits, and positively influences the urban microclimate.

“You increasingly hear the term infra-nature,” says Filip De Bonte, CEO of De Bonte Group. “Infrastructure cuts through cities and municipalities — concrete and greenery must find each other in that. Either you embrace that idea and start looking for solutions, or you resist it, but that’s not sustainable in the long run. Together with Taveirne, we’re proving through this project that we can be a reliable partner for De Lijn in that regard moving forward.”

The use of green tracks with prefabricated ladder elements combines ecological added value with technical robustness.

EFFICIENCY ON SITE

Up to 220 meters of ladder track modules can be installed each day, significantly shortening the project’s overall duration. After installation, the open spaces are filled with topsoil to ensure maximum water permeability. The entire section is then sown with grass, which not only enhances the green appearance and creates a more attractive streetscape but also helps prevent sand accumulation between the tracks.

The use of green tracks with prefabricated ladder elements combines ecological added value with technical robustness. The load-bearing substructure ensures stable track alignment without the need for traditional maintenance such as tamping. Forces are evenly distributed, resulting in a longer lifespan and lower maintenance costs.

Moreover, the green track structure fully complies with stormwater management regulations, greatly facilitating spatial integration. “The theory behind it is very sound,” says Lode Van Iseghem, Technical Director at Taveirne. “We strongly believe in the potential of this system, both technically and in terms of sustainability. The first results are very promising. And that it’s a high-quality product — thanks in no small part to De Bonte’s craftsmanship — is beyond doubt.”

PROJECT BREDENE

From constructing new railway lines to renewing and maintaining existing tracks and overhead lines, Taveirne ensures the development of a safe, stable, and reliable rail network.

Kristof Vonck, Project Manager at Taveirne, explains:

“The project in Bredene involved renewing the tracks and the overhead line. We also replaced one intersection at Zeelaan. The rest consisted of installing 2,200 meters of ladder track. The works were carried out in several phases, as the route had to remain operational during certain periods — especially during the holiday season.”

De Lijn had previously applied the ladder track system in a pilot project. “But that was a straightforward, linear section, whereas in Bredene we installed a curved track of more than two kilometers,” Vonck clarifies. “This project therefore presented quite a few logistical and technical challenges, such as extremely precise planning, detailed preliminary studies, and highly accurate placement and alignment of the tracks. The margin for error was exceptionally small — even smaller than in traditional ballasted track construction.”

VERY STRICT TOLERANCES

The required precision began long before work started on site. Filip De Bonte explains:

“Due to the complex 3D shape of the prefabricated concrete ladder element and the extremely strict placement tolerance of ±1 mm in all directions, Taveirne rightly imposed very high design requirements from the outset. The elements are not very forgiving during installation and alignment, which meant the manufacturer had to apply rigorous quality control and measurements accurate to 0.1 mm already in the factory. In particular, ensuring the flatness of the sixteen bearing surfaces within each rigid element required the utmost precision. All sixteen bearing points were 3D-measured and validated daily for each element to guarantee a perfectly matching assembly. Every element was assigned a unique dimension and position code, making mix-ups on site impossible.”

Before execution began, a test setup was developed in which traditional construction techniques were combined with advanced digital applications. A key instrument in this process was the use of a digital total station. Each site crew was equipped with one, enabling them to position the prefabricated elements completely autonomously, without the intervention of an external survey service. By combining experience with technology, craftsmanship was elevated to a higher level — not as an exception, but as standard practice for every team on site.

NO TRIAL RUN

The result? A smooth, methodical installation without any corrective demolition work. The combination of sharply defined technical requirements, a carefully designed production process, and a meticulously planned installation strategy led to flawless execution.

Kristof Vonck explains:

“For each ladder element, two fixed points were determined using a total station, which allowed us to position the ladders very precisely right from the start. We’re talking about 6-meter-long elements weighing 4 tons each. These were lifted and placed using a crane, after which the rails were installed. Marking those reference points on the prefabricated elements was absolutely crucial — when that’s done accurately, installation itself goes very smoothly.”

Lode Van Iseghem adds:

“When it comes to innovative systems and techniques, this is far from our first experience. We previously installed the first concrete turnouts and P-turnouts for Infrabel and implemented the first direct fastenings. We strongly believe in innovation as a necessary driver for progress.”

Filip De Bonte was impressed by Taveirne’s craftsmanship:

“I’ve known them for a long time and am familiar with their capabilities, but the team working on this project was truly outstanding. This project is without doubt a benchmark for the entire sector. What I particularly admire is that it’s not just about tried-and-tested techniques — there’s a lot of smart innovation as well. For instance, instead of using the newest equipment, they chose a machine that was perfectly suited to this task. The freedom we were given in the specifications, both in production and execution, was used to the fullest — and handled with great professionalism.”

PIONEERING WORK

For public transport operators and cities, the green track represents far more than just a technical solution — it is a way to make sustainability visible and tangible in the urban landscape. The system combines mobility, climate adaptation, biodiversity, and comfort into one integrated whole, perfectly aligning with contemporary policy objectives.

Contractor Taveirne and prefabrication specialist De Bonte Group responded with a well-thought-out concept developed through intensive collaboration. Custom molds for curves, superelevations, and even clothoid shapes make it possible to meet all design requirements along the route.

“Thanks to their extensive technical expertise, attention to detail, and close coordination with the client, true pioneering work was achieved — not only meeting the highest quality standards but also setting a reference for future projects. This collaboration is a testament to innovation, trust, and a shared ambition to push boundaries and deliver sustainable results,” concludes Benny De Bruyn, project manager at De Lijn, enthusiastically.