Construction during operations – efficient scheduling and spatial planning for smooth project execution.
The Lötschberg Summit Tunnel in Switzerland is the centerpiece of the Lötschberg mountain line from Spiez to Brig. On behalf of BLS AG, RSRG carried out the conversion of a 1.5 kilometre double-track section with four turnouts from ballasted track to slab track.
The Lötschberg Summit Tunnel is a 14.6 kilometre railway tunnel which opened in 1913. It connects the Bernese Oberland with the canton of Valais and plays a central role in BLS’s car transport service. At peak times, up to 180 car trains pass through the tunnel each day.
Due to the importance of the tunnel for railway traffic, the tracks in the construction section were renewed under partial closure or single-track operation. Track 100 was converted between early April and late June 2024, and track 200 between early July and the end of September of the same year. Total closures took place four to five nights per week depending on the holiday season, each from 01:00 to 05:00.
The challenge in the 1,500-metre-long section with four turnouts lay primarily in the short construction windows of only three months per track. Work was therefore carried out in two shifts with three teams on a 10-day cycle.
The existing tracks were dismantled at night using road-rail excavators, and the ballast was removed during the day using MFS excavators and traction units, allowing the section to be cleared within one week.
Due to the confined space, precise work with MFS crawler units was required. Because of these spatial constraints, the new turnouts (LVT-EW VI-900-1:19) were also installed using tunnel-based logistics and assembled directly on-site using road-rail excavators.
Despite all the challenges, the tracks were successfully reopened to traffic on schedule and to the full satisfaction of the client. The necessary clearance gauge checks were carried out efficiently using state-of-the-art technologies by RSRG’s Digital Rail Services.
Facts
Project Lötschberg Summit Tunnel
- Location: Bernese Oberland – Valais, Switzerland
- Client: BLS AG
- Scope: Conversion of 1.5 km of double track with four turnouts from ballasted track to slab track
- Construction phase: April bis Juni 2024
