A supply and demand system approach to bridge management

Transportation networks, and the bridges within these networks, exist to serve users. An optimal bridge management strategy can be defined as one that provides the minimum risk of disruption of service to the users of the transportation network for the allocated resources. This paper outlines the supply and demand system approach to the development of bridge management strategies. The approach, by using probabilistic methods, can take into consideration the multiple hazards that affect the ability of transportation networks to provide an adequate level of service. The optimal management strategies for a simple example, in which there is a risk of service disruption due to a traffic hazard scenario and a flood hazard scenario, are determined. The difference between the determinations of the optimal management strategies for the two hazard scenarios is highlighted. The use of the supply and demand system approach to determine optimal management strategies can decrease the risk of service disruptions and is applicable for hazard scenarios that affect bridges either individually or simultaneously.