The traffic bottleneck analysis on urban expressway under information condition

The development of information technology provide foundation to collect a large number of data for urban traffic management. These traffic data can be used to monitor traffic state surrounding the bottleneck and to analysis the evolution of the temporal and spatial rules of congestion. Based on the historical detector data, the new indexes have been proposed in this paper to evaluate the severity of the congestion. Using these indexes, the bottleneck on parts of eastern side of Shanghai north-south elevated road is analyzed. A bottleneck is firstly identified through the temporal and spatial changing graph of indexes, and then the activation time, deactivation time and the duration of bottleneck have been analyzed using transformed cumulative curves to serve for bottleneck analysis, which provides a theoretical basis for further analyzing the severity of the bottleneck. Research results can be further applied in publication of traffic state on urban expressway, in order to offer the services for traffic management and people´s travel.