At first glance, it may appear to be just another part of the facility. In reality, however, it is one of the most technically demanding elements of the AUREL Proving Ground development project in Břehyně near Doksy. We are talking about the underpass with its bridge structure, which formed part of the second phase of construction in 2024. Its primary purpose is to provide access to the inner area of the facility and all testing zones without the need to interrupt activity on the oval track. In this article, you will learn what makes such a bridge so important, how the construction process was carried out and how the structure influences the day-to-day operation of the proving ground.
An Ordinary Bridge Is Not Enough for a Proving Ground
From the very beginning, it was clear that this would not be “just a bridge”. The structure had to meet several key requirements:
- Provide access for all types of vehicles, from passenger cars and heavy goods vehicles to emergency response and fire service vehicles. These must also be able to enter the facility safely in the event of an emergency.
- Minimise any impact on the elevation profile of the oval track itself. The testing circuit had to remain as compact as possible, without unnecessary interruptions that could affect its functionality or the quality of testing.
- Maintain the same road structure as the rest of the oval track. The aim was to keep the upper asphalt layers as continuous as possible, ensuring that no transition would be noticeable when crossing the bridge and that vehicle behaviour during testing would not be affected.
The bridge was already included in the plans during the construction of the oval track, which is why the structure itself formed part of the original contract. From the outset, we worked closely with our project partners, SaM Česká Lípa and COLAS, to identify the optimal solution. The goal was to develop a design capable of meeting the requirements of the banked four-lane oval track, supporting the passage of heavy vehicles and remaining economically viable at the same time.
The Final Structural Design
The result of this collaboration is a roadway embedded into the rock beneath the oval track, ensuring that it does not interfere with the testing circuit itself. The bridge consists of a reinforced concrete structure that supports the oval track while simultaneously providing access to the inner part of the facility.
The retaining walls were constructed using a dry modular building method, eliminating the need for conventional on-site concrete casting. For this purpose, we used a dry construction system supplied by Geomat, combining precast concrete elements with geotextile reinforcement layers compacted throughout the road structure. This approach accelerated the construction process while maintaining the required level of structural stability.
Above the bridge structure, we retained the same combination of crushed aggregate, gravel and three asphalt layers used across the rest of the oval track. To create one continuous surface without transitions or uneven sections, the final asphalt layer was laid simultaneously by three asphalt pavers. As a result, drivers today are unable to detect any difference when crossing the bridge.
Safety and Long-Term Durability
As the proving ground is used by passenger cars, heavy goods vehicles and other heavy machinery, the structure also had to meet demanding safety requirements. The safety barriers installed on both the oval track and the bridge therefore comply with H2 containment standards. This means they are capable of withstanding the impact of a passenger car travelling at 100 km/h or a coach travelling at 70 km/h.
Long-term durability was another key consideration. To ensure the bridge can withstand at least 50 years of intensive operation, its foundation slab alone contains approximately 15 tonnes of reinforcing steel. The entire structure consists of nearly 30 tonnes of steel and 270 cubic metres of concrete.
What the Bridge Means for Proving Ground Operations
The main benefit clients appreciate is the smoother operation that the bridge makes possible. The inner area of the facility can now be accessed at any time without the need to interrupt testing activities on the oval track. This makes individual test programmes easier to schedule and eliminates unnecessary delays when moving vehicles and equipment around the site.
At AUREL, we understand that a high-quality proving ground is defined not only by the track itself, but also by the infrastructure that supports it. This is what enables us to provide testing services at the level demanded by today’s automotive industry. Whether you require development testing, prototype validation or a facility for demanding technical trials, get in touch with us – we will be happy to help you find the right solution.
