The Vereina tunnel is 19.1 km long and is characterized by mixed traffic, with conventional passenger trains and transport of road vehicles on train carriages.
The Vereina tunnel connects since 1999 Klosters-Selfranga with Susch-Lavin, in Eastern Switzerland. The tunnel is used for person transport as well as for carrying road vehicles on train carriages and is operated by the Rhaetian Railways (Rhätische Bahn RhB).
The key characteristics of the tunnel are:
Single-track tunnel, 19.1 km long, with crossing sections at the portal and in the center
Narrow-gauge tunnel (1 m)
Operation with passenger trains and with special shuttle trains transporting road vehicles (cars, busses and lorries)
The existing tunnel infrastructure and operation sets unusual challenges for person safety in case of fire incidents
After over 15 years of operation, a general renovation of the safety concept was required, due to both normative changes and evolving safety requirements
This involved practically all safety-relevant sectors, ranging from the tunnel infrastructure (e.g. ventilation and emergency exits, in particular in the crossing areas), rolling stock and train management over to the intervention concepts in case of incident within the tunnel.
Ventilation design for the all tunnels
Ventilation sensors, power supply and ventilation-control system
Tender design, construction design and site supervision
Intrinsic limitations resulting from the existing infrastructure
Unusual challenges arising from mixed traffic, including normal passenger trains, conventional HGVs and lorries
All interventions to be carried out under traffic, with night closures
All new safety concepts should apply as much as possible for the whole line
Cost-effectiveness of all measures
Time scheduling of the investments, for achieving economic sustainability
Investigation of the potential consequences of vehicle fires on the shuttle trains
Analysis of existing safety concept and identification of potential for improvement
Investigation of possible additional mitigating measures, including new facilities for self-rescue
Development a new tunnel safety concept, taking into account infrastructure, operation and rescue
Investigation of consistent safety packages and development of a time schedule for matching the available financial resources
Detailed investigations on self-rescue facilities, ventilation and fire scenarios