  The wellbeing of modern societies is dependent upon the functioning of their
infrastructure networks. This paper introduces the 3C concept, an integrative
multi-system and multi-stakeholder optimization approach for managing
infrastructure interventions (e.g., maintenance, renovation, etc.). The
proposed approach takes advantage of the benefits achieved by grouping (i.e.,
optimizing) intervention activities. Intervention optimization leads to
substantial savings on both direct intervention costs (operator) and indirect
unavailability costs (society) by reducing the number of system interruptions.
The proposed optimization approach is formalized into a structured mathematical
model that can account for the interactions between multiple infrastructure
networks and the impact on multiple stakeholders (e.g., society and
infrastructure operators), and it can accommodate different types of
intervention, such as maintenance, removal, and upgrading. The different types
of interdependencies, within and across infrastructures, are modeled using a
proposed interaction matrix (IM). The IM allows integrating the interventions
of different infrastructure networks whose interventions are normally planned
independently. Moreover, the introduced 3C concept accounts for central
interventions, which are those that must occur at a pre-established time
moment, where neither delay nor advance is permitted. To demonstrate the
applicability of the proposed approach, an illustrative example of a
multi-system and multi-actor intervention planning is introduced. Results show
a substantial reduction in the operator and societal costs. In addition, the
optimal intervention program obtained in the analysis shows no predictable
patterns, which indicates it is a useful managerial decision support tool.
