Post-earthquake resilience optimization of a rural “road-bridge” transportation network system

Abstract

Rural traffic systems have a sparse number of roads and bridges. Under the action of an earthquake, the damage to bridges in the “road-bridge” transportation network (r-bTN) system will not only cause the loss of road capacity but also hinder post-earthquake rescues and recovery. To reduce the impact of the r-bTN system on post-disaster recovery activities, this paper proposes an optimization model of an r-bTN system with bridges as the key links under the concept of resilience recovery. In this model, the average time delay was proposed to evaluate performance of the rural r-bTN system after an earthquake. The total recovery time and cumulative benefit rate were proposed to measure the r-bTN system resilience in the recovery process. In addition, the constraints of bridge functionality change with time, and the number of engineering teams are considered. To illustrate the proposed optimization model, a multi-objective non-dominated sorting genetic algorithm is used to solve the restoration schedule optimization problem for a rural r-bTN with 45 nodes, 74 roads, and 15 bridges subjected to seismic events. This model provides decision support for the restoration of the rural r-bTN system shortly after an earthquake.