Engineering firm contributes to safer and better traffic flow with rail underpass 

Underpass in operation since May 2023 

To achieve greater safety and less disruption at and around level crossings, WSP has designed a large number of railroad underpasses in recent years as part of ProRail's Tunnel Alliance Program. One of these is the tunnel on the Laan van Osseveld in Apeldoorn, a structure finished with Corten steel and green slopes that was completed in May 2023 to replace a level crossing. A challenging and special project, not least because the project site is literally on the doorstep of one of the ten WSP offices in the Netherlands....

As a global provider of engineering and consultancy services in the fields of Transport & Infrastructure, Property & Building, Earth & Environment and Power & Energy, WSP, which has been operating in the Netherlands since 2019, is at home in many markets. Among other things, the ProRail-approved company specializes in the design of civil and structural works on and around the railroad. When it comes to the realization of substations and relay houses, but also when the renovation of stations, platform caps and NS bicycle sheds are on the program. 

Total approach

WSP has been involved in so-called tunnel alliance projects for various clients for a lustrum of time. The aim is to contribute to a solution for important traffic congestion points and unsafe level crossings. According to Jeroen van Dijk, who works within the company as design and team leader Infra Nieuwegein, this has everything to do with the extensive experience and expertise the consultancy and engineering firm has at its disposal. "WSP not only provides advice, but also has an eye for the practical details in execution engineering. For example, we also have knowledge of all the special implementation techniques involved in realizing a railroad underpass. In addition, our experts are always sitting around the table, so the lines of communication are short and we can switch quickly. This makes our office a much sought-after party for the elaboration of civil constructions. From tender design to site engineering."

"Many underpasses often have an architectural aspect. In the design worked out together with the architect for the recently inaugurated underpass in Apeldoorn, for example, we chose a finish with Corten steel and expanded metal, two viewing points, stairways and green slopes. That combination has produced a visually stunning result."

Hussar

A characteristic of the construction of a railroad underpass is that the railroad crossing part of it must be realized in a short period of time. For the underpass on the Laan van Osseveld, for example, an almost 7,000-ton 'railroad leg' was pushed into the track during a 120-hour out-of-service period with the aid of sliding tracks and jacks. A true feat and a fine example of how design and execution can come together in practice, Jeroen believes. "In close consultation with the contractor, the design of the concrete structure was tailored to the auxiliary structures required for sliding in the railroad leg. In addition, the project has a nice extra dimension. After all, the railroad underpass is right in front of our Apeldoorn branch office. That fact ensured that together with the contractor, who operated from our premises during the project, we were nice and close to both the customer and the work." 

From level crossing to railroad tunnel in 15 months

The new underpass on Laan van Osseveld, a major traffic artery and also part of the Apeldoorn ring road, will lead to increased traffic safety and improved traffic flow. "For car traffic, two times two lanes have been constructed in the tunnel with unobstructed bicycle and pedestrian paths on both sides. The previously level crossing bicycle and pedestrian traffic has also been made level by means of a bridge installed over the tunnel," Jeroen says of the project, which was completed within a time frame of about 15 months. 

Construction company Hegeman Bouw & Infra, which carried out the project on behalf of ProRail, pre-built the concrete structure under the track in its entirety on the work site on the north side of the track. Subsequently, the structure was pushed into place in one go. Simultaneously with the preconstruction, the concrete structure of the southern access ramp was installed on the other side of the track, thus reducing the required construction time. This approach ensured that inconvenience to (train) traffic and the surrounding area was limited.