Structural retrofitting of rescue tunnels in single shell shotcrete construction – requirements and experiences

As a result of the devastating fire events in the transalpine tunnels at the turn of the millennium, the EU Tunnel Directive (2004/54/EC) was developed. The Directive provides that the distances between the emergency exits shall not be more than 300 m. The national implementation of the Directive in Germany was the Guidelines for the Equipment and Operation of Road Tunnels (RABT) 2006. The stipulations in the RABT created the re-equipment needs of the - at that time - round about 200 existing federal road tunnels. To ensure the lower emergency exit distances several cross passages, rescue shafts and – since about 50% of the existing tunnels are operated bi-directionally – rescue tunnels had to be build. Please click Additional Files below to see the full abstract