Damage processes and performance indicators for tunnel structures

Infrastructures such as bridges and tunnels should be designed to cater for a defined function. This typically mirrors the distance of travel or the level of traffic flow. Infrastructure networks in most countries will therefore reflect the development of a hierarchy of infrastructure, with motorways at the highest level and local access roads at the lowest. In practice, a hierarchy will naturally emerge as the more heavily used infrastructures are constructed with stricter standards. But it is important that the hierarchy is established to clear guidelines by linking design to function, throughout the network. This is particularly necessary where different functional levels or different geographical areas are managed by different infrastructure operators. In this contribution, the focus associated with the classification for infrastructures is on tunnels. The classification is based on vulnerability and consequence class concepts and comprises objects built after the 60's.