ABSTRACT
The assessment of the life-cycle performance of deteriorating structures can be formulated as a reliability problem where a loss of performance greater than prescribed threshold values is considered as a failure. Therefore, when a failure is reached, the system passes from the current state to another state characterized by a lower level of performance. On the other hand, structural performance can also be improved by maintenance and/or rehabilitation interventions. In this case the system may move from the current state to another state characterized by a higher level of performance. However, in both cases the failure process may be defined as a transition process through different service states due to environmental attacks and/or maintenance actions. Clearly, since the problem is affected by several sources of uncertainty, the assessment of the life-cycle performance must be based on a suitable damage modeling and on a probabilistic analysis able to model the main features of the time-variant deterioration process (Biondini et al. 2004, 2006a, Biondini and Frangopol 2008).
