Connecting renewable energy projects to existing power networks can present significant challenges if routes cross through existing infrastructure.

For a renewable energy infrastructure project in Ludwigslust, Germany, a new underground crossing spanning 72 metres was required to connect a photovoltaic installation to a municipal power grid.

With the planned route passing beneath a high-speed railway line and through a protected vegetation area, a solution was needed that could deliver a reliable and long-term connection while minimising disruption to the surrounding infrastructure and environment.

The project was designed by consulting engineer EGA Plan GmbH and delivered by specialist contractor Witte Spezialtiefbau. Steinzeug-Keramo supplied 72 metres of DN 500 KERA.Drive vitrified clay jacking pipes for a microtunnelling approach using a slurry system beneath the railway. The KERA.Drive system acts as a durable protective pipe for the utility connection, designed to minimise future maintenance requirements.

Overcoming complex challenges

The project presented significant challenges. Firstly, the crossing was beneath an active high-speed railway line, which ran through a cutting approximately four metres below the surrounding ground level. Construction therefore needed to be carefully controlled to minimise ground movement and protect the stability of the railway infrastructure.

Adding to the challenges was the route passing through protected vegetation areas, meaning environmental restrictions limited the level of surface disruption that could be permitted. This also meant that future access for inspection, maintenance or repair would be difficult. The selected pipe system therefore needed to provide high levels of durability while minimising future maintenance requirements.

The trenchless solution

A microtunnelling approach using a slurry system was selected to overcome the project’s complex installation requirements and enable safe and precise installation. The crossing was constructed using DN 500 KERA.Drive vitrified clay jacking pipes, installed at a depth of approximately 9 metres, providing the required cover beneath the railway structure and enabling a precise, low-settlement crossing.

Steinzeug-Keramo’s KERA.Drive vitrified clay pipes were selected due to their high compressive strength, dimensional accuracy, consistent geometry and ability to withstand demanding installation conditions. The smooth vitrified surface helps to reduce friction, minimise jacking forces and support a controlled microtunnelling operation.

The system is designed for safe and controlled jacking, ensuring precise alignment and leak-tight connections throughout the installation network. Its smooth, glazed internal surface provides favourable conditions for cable installation within the protective pipe. With a service life exceeding 150 years, KERA.Drive offers a low-maintenance solution for utility infrastructure projects, while its natural vitrified clay construction makes it a durable and sustainable choice.

Results

The trenchless approach, paired with Steinzeug-Keramo’s vitrified clay jacking pipes, successfully delivered a crossing beneath high-speed railway infrastructure, avoiding the need for extensive surface excavation within a sensitive environment.

The installation was completed with a high degree of precision, despite the additional challenges presented by the project.

Trenchless installation also enabled the crossing to be constructed while keeping surface disruption to a minimum. This was particularly important given the active railway and protected vegetation areas along the route. Overall, the successful installation of Steinzeug-Keramo’s KERA.Drive provides a corrosion-resistant, durable and low-maintenance protective pipe system for the utility connection.

A reliable trenchless solution for utility crossings

The Ludwigslust project demonstrates how critical utility infrastructure can be delivered despite challenging geometric, environmental and operational constraints. The combination of a deep railway cutting, stringent cover requirements and limited future accessibility demanded a precise and dependable trenchless solution.

Lorenzo Vidus Rosin, Sales Engineer at Steinzeug-Keramo, says: “Where future access is limited, long-term reliability becomes critical. Our KERA.Drive pipes provided the durability, installation performance and operational reliability required for this utility infrastructure project, which is expected to remain in service for generations.”

In summary, for renewable energy projects requiring underground crossings beneath roads, railways or environmentally sensitive areas, trenchless installation with KERA.Drive vitrified clay pipes offers a reliable, low-disruption and long-term solution.

For more information about Steinzeug-Keramo, visit: www.steinzeug-keramo.com

Or contact: uk.steinzeug-keramo@wienerberger.com