Assessment of level of service measures for two-lane intercity highways under heterogeneous traffic conditions

摘要

Many researchers have studied the performance of two-lane intercity highways with the help of different measures. In the current study, the performance of such highways under heterogeneous traffic conditions was examined by using several speed and followers related measures. The data were collected from five study sites located in different regions of India. A new methodology was proposed where followers were identified by using a speed difference (between two consecutive vehicles) range of -4 to +10 km/h and gap threshold value (lower than a particular gap value) of 10 s. By using acceptance curve method, different critical gap values were suggested for each site to identify the followers. Out of all the performance measures, the number of followers as a proportion of capacity (NFPC) and follower density were found to be the best and second best parameters. Finally, different level of service ranges were proposed based on NFPC using cluster analysis.