This paper proposes a simplified methodology to adjust the load/resistance safety factors for use in the design

criteria of concrete tunnel linings when the service life requirements depart for coded standards in Ultimate

Limit State (ULS. This is achieved on the basis of the reliability level prescribed to the structure at the very beginning

of its lifetime (during design), while some assumptions are verified through probabilistic simulations.

Furthermore, this is discussed in consistency with the reliability concepts indicated in Eurocode 0 “Basis of

Design”.