Culvert and underpass for pedestrians and bicycles under the train tracks in Spånga

Location: Spånga, Stockholm (Sweden)
Client: Trafikverket
Budget: 360 324 000 kr (≈36,5Mill €)
Construction Period: Sep20-Jun 2023

Characteristics
The project includes two clearly differentiated actions. On the one hand, the design and build of a pedestrian and cycle path that will connect the areas of Bromsten and Spånga that are currently separated by a railway infrastructure. For this purpose, the existing level crossing at Fristadsvägen will be replaced by an underpass that will go under the tracks. In addition, in the areas surrounding the underpass, landscaped areas will be designed to give the environment a more social character. On the other hand, the project includes the design and build of a 260m long culvert that also crosses under the train tracks. The size of this culvert is designed to absorb the large increase in water flow expected in the area.

This project has faced two major challenges: on the one hand, the difficulty of working in the environment of a railway infrastructure with more than 250 trains per day. This entails, a technical challenge, detailed planning and additional safety risks. On the other hand, the complexity of the geotechnical environment due to the sensitive clay soils and the fact that it is in a semi-urban environment, which means that the entire execution of the works has to be carried out with sheet piling and pumping of water from the groundwater table.

Finally, it should be noted that for the construction of the tunnels, Rover Infraestructuras designed a launch process for both the pedestrian and bicycle underpass (21m long and 998Tn) and the culvert (23.5m long and 534Tn). Both construction processes were carried out during one single track closure with a duration of 24 days.