Expansion of Bern RBS Station: challenging urban tunnelling in the Swiss capital

The “Expansion of Bern RBS Station” project involves the construction of a new underground station and its access line. The new RBS station consists of two station caverns, 200 m and 210 m long respectively as well as 26 m wide and 17 m high, which are located 12 m below the existing tracks of Bern Central Station. The 1.5 km‐long access line has varying cross‐sections and is being constructed using both underground and cut and cover methods. All structures are close to the surface and are being constructed under challenging inner‐city conditions. They are located mainly in soft rock and partly in water‐bearing soil. The exceptionally challenging construction is being carried out with a thin overburden, partly beneath high foundation loads, and within the existing structure, in parallel with other expansion projects and whilst the existing railway facilities at Bern Central Station and the RBS infrastructure remain in operation.