Efficient and sustainable – the new generation of road drainage covers
How changes in construction practices can make road building more economical and sustainable.

A high-performance surface drainage system is essential for the operational and traffic safety of roads. The sharp increase in traffic loads in recent years has already led to structural adjustments in sewer construction—for example, wall thicknesses of shaft components have been increased from 90 mm to 120 mm in accordance with DIN 4034. Additionally, rollable shaft covers have become standard practice, helping to reduce stress on the shafts.

However, road drainage has remained largely unchanged for over half a century. It still relies on roadside gutters with integrated drainage inlets based on DIN 4052. Constructing these paved gutters is both time-consuming and costly. The load from traffic is transferred directly from the cover to the drainage body. In response to increasing traffic loads, some projects have upgraded to Class D 400 covers instead of Class C 250. But reinforcing the cover alone is ineffective if the underlying structure remains unchanged - concrete components per DIN 4052 still have an unreinforced wall thickness of just 50 mm.

Unlike sewer systems, road drains are rarely inspected regularly. Damage is often only discovered when visible signs appear, such as surface settlement or broken frames. By then, repairs are complex and expensive. The current method of constructing paved gutters is both labor-intensive and costly. A critical weakness lies in the direct load transfer from the cover to the drainage body.

ACO Multitop Bituplan – Rollable Covers for Smarter Road Construction

ACO Multitop Bituplan covers offer a new, economical and sustainable solution. They are compatible with standard concrete components per DIN 4052 and ACO Combipoint drainage bases. Like the Multitop shaft covers, they can be rolled directly into the asphalt surface and seamlessly integrated into the road construction process. This allows the asphalt layer to be extended economically up to the curb without the need for a paved gutter. The cover does not interfere with asphalt paving and is simply rolled in, resulting in a flush finish. The risk of the cover protruding over time is virtually eliminated. Another key advantage: the cover is suspended within the pavement and decoupled from the drainage body. Traffic loads are distributed into the surrounding pavement structure, making the concrete base essentially a lost formwork. As a result, the drainage body is no longer exposed to significant traffic stress. Naturally, the new Bituplan covers retain all the proven benefits of the Multitop series: lightweight grates, traffic-safe screwless locking systems, rattle-free operation thanks to PEWEPREN dampers, and a wide range of grate designs for various applications.

Further information at www.aco.de/multitop-aufsaetze