ZEB Bern Wylerfeld

Background:
In Bernese Wylerfeld, the eastern entrance to Bern railway station, the much-frequented railway lines Zurich/Biel-Bern and Thun-Bern join together. These three tracks from Zurich/Bienne and the two lanes from Thun lead into four lanes to Bern station. This is why the routes of these trains partly overlap. This limits capacity and hinders the expansion of long-distance and regional services. The construction site is located directly in front of the SBB headquarters in Wankdorf.

Project contents:
This project oversees a single-lane 300-metre-long underpass. Seen from Bern railway station, it crosses under three lanes between Wylerfeld and the Bern Wankdorf Süd stop and leads into the line to Thun. This deconcentration allows trains to cross at different levels at the same time without obstructing each other. In order to be able to construct the structure, extensive modifications to the tracks and the Bern Wankdorf South stop (Bern-Thun line) are necessary. These costs were estimated at CHF 270 million.

SBB has divided the project into different lots. The contract for the GC Bahntechnik lot was awarded to the syndicate Wylerfeld, consisting of Rhomberg Bahntechnik, Sersa Group Schweiz, Sersa Technik and Sersa Maschinenller Gleisbau, with a Project implementation: value of CHF 15.4 million. The construction lots were awarded to Strabag and to consortium Frutiger-Marti. SBB IH is constructing the track systems for the operating tracks, and is building the catenary system and SA interior system.

Scope of general contractor railway technology:
Our lot comprises of services in 20 construction phases until 2023. 15km of track, 57 points and 20km of cable, SA outdoor installations, switch heating systems have so far been demolished and 13km of track newly built. The project also strengthens the group's internal cooperation.

The safety of the work alongside the operating plants places high demands on the crew. As one of SBB's substations is located in the area of Wankdorf station, grounding is a topic that must be constantly taken into account during dismantling. A cut open track is not grounding for a track excavator. Due to the dismantling of the track system, feeder line masts were temporarily standing on the tracks without earthing.
Cooperation between SBB project management, SBB IH, and the participating contractors places high demands on construction managers and construction site staff. Often, the accessibility of the site itself causes more problems than the execution of the work.

Building during operations
The work is carried out during railway operations on an isolated construction site and at night intervals and weekend part closures.

Technical Data