Evaluating the impact of real-time traffic control measures on the resilience of urban road networks

This paper proposes a methodology to evaluate the performance of a road network during non-recurring congestion for real-time traffic control applications. A novel performance indicator based on the concept of the macroscopic fundamental diagram (MFD) is developed to assess the travel production of the network. The proposed indicator is obtained by calculating the weighted space-mean flow of an urban network, which is a proxy for the travel production of the corresponding network. The resilience of the road network is defined as its ability to retain the same level of travel production after occurrence of a disruption. This paper shows how real-time traffic control measures can enhance the resilience of the network. More specifically, the impact of re-routing as a real-time traffic management measure is investigated in a network where a link is closed due to an unpredictable incident. The main advantage of this approach in comparison to the existing travel time based approaches is that it neither requires a detailed model of the network nor a calibration of a dynamic traffic assignment model for different demand scenarios, as the MFD is a property of the network and is not sensitive to small changes in demand.