New road surface for circuit Zolder

It had been 15 years since the famous circuit had received a new layer of asphalt, so it was high time to restore the circuit to its glory. Main contractor APK and cooperating parties called on Topcon for a 3D measurement of the circuit, 3D free technology, GPS-guided rollers and intensive service. Joint result is a perfect new road surface.

Comfortable and safe driving

David Vanderbeek, responsible for the infrastructure of Circuit Zolder: "The asphalt on a circuit has to be renewed every ten to fifteen years on average. The road surface was still in very good condition by 'normal' standards, but speeds of 230 km/h are reached on this track. In those conditions, every crack and unevenness in the road has a huge impact. By renovating the track, we wanted to increase not only safety, but also the comfort of the drivers."

From road surface scanning to milling: everything in 3D

APK led the project and engaged several partners. First up was Top-Off to mill out the existing asphalt layer. Top-Off and Topcon are no strangers; their partnership has been successful for more than ten years. The decision to 3D mill this project was therefore quickly made. Before the team actually started, the existing situation was measured with an IP-S3, a mobile mapper from Topcon.

"Topcon not only provided the 3D measurement of the track, but was intensively involved in the entire project. They listened to our wishes and made adjustments where necessary. Until the final phase, we could count on them." APK - main contractor of the project 

With Topcon's SmoothRide system, important spots such as the chicanes were precisely measured in no time. This made it clear where the bad spots in the road surface were that needed to be improved for optimal results. In this way, the track could be milled out faster and to millimeter accuracy.

"More than ten years ago, we chose Topcon as our exclusive partner. The successful cooperation at Circuit Zolder proves once again that we are a strong team." Top-Off - executor of the milling works at Circuit Zolder

Asphalting with optimal processing temperature and compaction

After milling out, APK placed the new curbstones and drainage ditches, after which it was time for the new asphalt layer. This was placed by Grizaco. The composition of the asphalt remains - as with all reputable racing circuits - a closely guarded secret. The placement was monitored in real time using Pavelink. With this software module, transport planning could be controlled so that the asphalt had the optimal processing temperature during the process.
The rollers behind the asphalt spreaders were equipped with a Topcon-GPS system which assured Zolder of optimal compaction of the asphalt: a real added value since several asphalt spreaders worked simultaneously. The rollers could thus work overlapping; the beamman was shown a color map on which the number of transitions on the track appeared live on all screens.

Lineation with a robot

Finally, Ultimated provided the tracing for the lines on the track; not an unimportant part during high-speed races. A robot was used to plot the points and lines. In places where GNSS was insufficient, the robot was controlled with a Topcon Total Station to trace the lines. In the future, this method will prove its worth more often in road construction: it allows not only faster, but also more accurate, more versatile and safer work.

A successful test drive

Andy Jaenen, a familiar face in the racing scene and an experienced driver, was among the first to test the track after the works. His reaction: "The road surface has been levelled out nicely and the corners are better, which gives you more grip. This ensures even better times and less wear on the tires. Especially during races like the '24 Hours of Zolder', the new asphalt will make a big difference." Due to the corona measures, big events will have to wait a while, but until then the circuit is open for individual practice runs. This way, drivers can already get acquainted with Zolder's brand new road surface.