The importance of travel time reliability in traffic management, control, and network design has received a lot of attention in the\npast decade. In this paper, a network travel time distribution model based on the Johnson curve system is proposed. The model is\napplied to field travel time data collected by Automated Number Plate Recognition (ANPR) cameras. We further investigate the\nnetwork-level travel time reliability by connecting the network reliability measures such as the weighted standard deviation of travel\ntime rate and the weighted skewness of travel time rate distributions with network traffic characteristics (e.g., the network density).\nThe weighting is done with respect to the number of signalized intersections on a trip. A clear linear relation between the weighted\naverage travel time rate and the weighted standard deviation of travel time rate can be observed for different time periods with\ntime-varying demand. Furthermore, both the weighted average travel time rate and the weighted standard deviation of travel time\nrate increase monotonically with network density.The empirical findings of the relation between network travel time reliability and\nnetwork traffic characteristics can be possibly applied to assess trafficmanagement and controlmeasures to improve network travel\ntime reliability.
Loading....