Lertworawanich, Ponlathep (Department of Highways, Sri-Ayudhaya Road, Ratchatevi, Bangkok 1)

How Passenger Car Equivalents (PCEs) Change with Densities?

Scheduled for presentation during the Regular Session "Traffic Theory for ITS" (FrBT12), Friday, September 27, 2024, 13:50−14:10, Salon 20

2024 IEEE 27th International Conference on Intelligent Transportation Systems (ITSC), September 24- 27, 2024, Edmonton, Canada

This information is tentative and subject to change. Compiled on October 3, 2024

Abstract

Unlike passenger cars, heavy vehicles require more space and exhibit distinct driving characteristics due to their size and weight. These differences necessitate a reliable measure to assess their effect on traffic operations. Passenger Car Equivalents (PCEs) are used to quantify the impact of a heavy vehicle as equivalent to a certain number of passenger cars, thereby aiding traffic engineers in congestion management. A key finding of this study is that PCE values are not static; they change with traffic densities and are influenced by the shape of the fundamental diagram. In uncongested conditions, PCE values tend to increase with density, indicating that trucks have a greater impact on traffic operations. In congested conditions, if the diagram remains concave, PCE values start to decline with increasing density, implying that trucks have a lesser impact on traffic flow during congestion. Conversely, in congested conditions, if the fundamental diagram is convex, PCE values continue to rise with density, suggesting that trucks exacerbate congestion.