Joint optimization of workforce scheduling and routing for restoring a disrupted critical infrastructure

Highlights: • Propose a joint optimization approach for scheduling restoration tasks and routing restoration teams to fulfill them. • Study the restoration of critical infrastructures with geographically distributed components. • Multiple teams and their coordination are studied. • Two different types of ant colony optimization algorithms are developed. -- Abstract: Once a critical infrastructure is disrupted, it needs to be restored as soon as possible in order to minimize the influence of the disruptions on the economic development and social well-being of a society. Components of critical infrastructures are usually geographically distributed and the time required to travel between disrupted components cannot be ignored when making restoration plans. As a result, the problem of optimally routing restoration workforce needs to be taken into account when scheduling the tasks of restoring disrupted components. To deal with this problem, this research proposes a joint optimization approach to simultaneously determine the time of restoring each disrupted component, the assignment of restoration tasks to the available teams of restoration technicians, and the routes of each team. To deal with the complexity of the proposed problem, ant colony optimization algorithm is employed with necessary adaptations to solve it.