All projects

Below-grade roadway A4

From A to B, from north to south, from left to right… the Netherlands has a busy road network. Amsterdam contractors on their way to a job in Best, Frisians on a shopping jaunt to Roermond, and Sparta supporters en route to an away game in the Gelredome Stadium… and they all have to return home again. A great many of these people travel by car over one of the country’s national trunk roads. Fortunately our infrastructure is generally up to the task, but to keep the roads good they must be maintained. The Department of Public Works (Rijkswaterstaat) is responsible for the national trunk roads in our country, and they recently turned their attention to the A4. Kamplacon was given the opportunity to make a unique contribution to this project.

Limes aqueduct

In total, seven kilometres of new motorway will be constructed between Delft and Schiedam. In the section between the Burgerveen and Leiden junctions the road will be widened to three lanes in each direction. The roadway will be below grade over a length of 1,400 metres. The below-grade roadway includes an aqueduct, and Kamplacon fitted this so-called tunnel with 15,000 m2 of sandwich panels and 8,300 m2 of ceiling cladding. On such a busy and important route there are many important aspects. Naturally, safety and functionality come first. But that is not to say the new below-grade roadway cannot also be visually appealing. With the lovely lines of the concrete and tasteful colours of the inner finishing, the redesigned A4 offers a pleasant driving experience.

High fire-resistance rating

So now everything is tip top by Leiden again. Traffic flow has been improved by the extra lane, which also promotes road safety. The below-grade roadway has improved the quality of life for local residents. The cladding is also sound absorbent. What is even more important, however, is that the cladding amply meets the established safety regulations. The panels have a high fire-resistance rating, for example, which can provide precious extra time during emergencies in a tunnel. On top of that, a total of seven different RAL colours were used. Functional? Check. Safe? Check. Attractive? Check out the photos and the video, or take a drive through the tunnel yourself! After all, it has been finished for some time now.