The effect of a new intercity expressway based on travel time reliability using electronic toll collection data

This study describes a method of evaluating the level of service of road networks, based on the average travel time and travel time reliability using electronic toll collection (ETC) data. The authors focused on the variance in travel time under normal circumstances, thus, traffic accidents were removed from the database, and any effect of individual vehicle preference was excluded. They evaluated the travel time distribution based on the average travel time from ETC data for each 15-min interval. The level of service in an actual intercity highway network was analysed using the proposed method. This analysis showed that the level of service fluctuated according to the road section analysed, the month and the time of day. These findings were confirmed by the shape of the cumulative distribution and indices of average travel time and travel time reliability. Using the evaluation method described here, the analysis also confirmed the change in travel time distribution between major interchanges after the opening of a new intercity highway route. As a great change in the traffic conditions occurred, the authors analysed the relationship between traffic demand and the level of service using detector data.