Ligerz Tunnel: Civil engineering capacities in a multipack
The most important structures of the railroad section for Lot 2 - the west and east portals and the 2.1 km long tunnel - place the highest demands on the entire range of specialized civil engineering skills. Tunnel construction, civil engineering, special foundation engineering, marine works and railroad technology are all intensively involved in a complex construction process that is coordinated hand-in-hand with ongoing rail and road operations and in the tightest of spaces - until the planned completion at the end of 2029.
Material transport by sea, biodegradable explosives
The project has many other special features in store: all the excavated material will be transported by sea in specially constructed pontoons. An innovative, biodegradable emulsion explosive will be used for blasting the entire tunnel, which produces no harmful nitrogen oxides and massively less CO2. The construction work is taking place in a region that is listed and protected as "nationally significant". In addition, a groundwater protection zone, a fish farm and numerous archaeological sites along Lake Biel require the utmost precision and care.
The project combines the disciplines of tunnel construction, civil engineering, special foundation engineering, marine works and railroad technology
An innovative, biodegradable emulsion explosive is used for the blasting work
Picture: ©SBB
The Ligerz Tunnel project
The aim of the project is to eliminate the last railroad bottleneck on the Jura river line between Lausanne and Biel. A new double-track tunnel is being built due to the narrow space between the lake and the slope, where the N5 national road and the cantonal road also run.
The project includes the construction of the 2.1 km long twin-track tunnel in Ligerz. The project will be carried out over around 1,850 m using the mining method and around 250 m using cut-and-cover - including concrete lining and railroad technology. In addition, four escape tunnels, a 114 m long viaduct for the N5 highway exit and various additional structures will be built. The excavated and excavated material will be transported by ship and the existing railroad line will be dismantled and redesigned.
