Delay-based Passenger Car Equivalent at Signalized Intersections in Iran
Due to their different sizes and operational characteristics, vehicles other than passenger cars have a different influence on traffic operations especially at intersections. The passenger car equivalent (PCE) is the parameter that shows how many passenger cars must be substituted for a specific heavy vehicle to represent its influence on traffic operation. PCE is commonly estimated using headway-based methods that consider the excess headway utilized by heavy vehicles. In this research, the PCE was estimated based on the delay parameter at three signalized intersections in Tehran, Iran. The data collected were traffic volume, travel time for each movement, signalization, and geometric design information. These data were analysed and three different models, one for each intersection, were constructed and calibrated using TRAF-NETSIM simulation software for unsaturated traffic conditions. PCE was estimated under different scenarios and the number of approach movements at each intersection. The results showed that for approaches with only one movement, PCE varies from 1.1 to 1.65. Similarly, for approaches with two and three movements, the PCE varies from 1.07 to 1.99 and from 0.76 to 3.6, respectively. In addition, a general model was developed for predicting PCE for intersections with all of the movements considered. The results obtained from this model showed that the average PCE of 1.5 is similar to the value recommended by the HCM (Highway Capacity Manual) 1985. However, the predicted PCE value of 1.9 for saturated threshold is closer to the PCE value of 2 which was recommended by the HCM 2000 and HCM 2010.
Knipling R, Waller P, Peck R, Pfefer R, Neuman T, Slack K, et al. NCHRP Report 500: Guidance for Implementation of the AASHTO Strategic Highway Safety Plan, Volume 13: A Guide for Reducing Collisions Involving Heavy Trucks. Transportation Research Board, Washington, DC; 2004.
Brodie L, Lyndal B, Elias IJ. Heavy vehicle driver fatalities: Learning's from fatal road crash investigations in Victoria. Accident Analysis & Prevention. 2009;41(3):557-64.
Al-Kaisy AF, Hall FL, Reisman ES. Developing Passenger Car Equivalents for Heavy Vehicles on Freeways During Queue Discharge Flow. Transportation Research Part A: Policy and Practice. 2002;36(8):725-42.
Kockelman KM, Shabih RA. Effect of Vehicle Type on The Capacity of Signalized Intersections: The Case of Light-Duty Trucks. Journal of Transportation Engineering. 1999;126(6):506-12.
Benekohal RF, Zhao W. Delay-based passenger car equivalents for trucks at signalized intersections. Transportation Research Part A: Policy and Practice. 2000;34(6):437-57.
Adnan M. Passenger Car Equivalent Factors in Heterogeneous Traffic Environment-are We Using the Right Numbers? Procedia Engineering. 2014;77:106-13.
McShane WR, Roess RP, Prassas ES. Traffic Engineering. New Jersey: Prentice Hall; 1998.
Branston D, van Zuylen H. The estimation of saturation flow, effective green time and passenger car equivalents at traffic signals by multiple linear regression. Transportation Research. 1978;12(1):47-53.
Sumner R, Hill D, Shapiro S. Segment passenger car equivalent values for cost allocation on urban arterial roads. Transportation Research Part A: General. 1984;18(5):399-406.
Ingle A. Development of Passenger Car Equivalents for Basic Freeway Segments. Blacksburg, Viginia: Virginia Polytechnic Institute and State University; 2004.
Anwaar A, Van Boxel D, Volovski M, Anastasopoulos PC, Labi S, Sinha KC. Using Lagging Headways to Estimate Passenger Car Equivalents on Basic Freeway Sections. Journal of Transportation of the Institute of Transportation Engineers. 2011;2(1):5-17.
Saha P, Hossain QS, Mahmud HMI, Islam MZ. Passenger Car Equivalent (PCE) of Through Vehicles at Signalized Intersections in Dhaka Metropolitan City, Bangladesh. IATSS Research. 2009;33(2):99-104.
Obiri-Yeboah AA, Tuffour YA, Salifu M. Passenger Car Equivalents for Vehicles at Signalized Intersections within the Kumasi Metropolis in Ghana. IOSR Journal of Engineering. 2014;4(4):24-9.
Sarraj YR. Passenger Car Equivalents at Signalized Intersections for Heavy and Medium Trucks and Animal Driven Carts in Gaza, Palestine. International Journal of Emerging Technology and Advanced Engineering. 2014;4(2):80-8.
Al-Kaisy A, Jung Y, Rakha H. Developing passenger car equivalency factors for heavy vehicles during congestion. Journal of transportation engineering. 2005;131(7):514-23.
Richardson AJ, Ampt ES, Meyburg AH. Survey Methods for Transport Planning: Eucalyptus Press; 1995.
Rathi AK, Santiago AJ. Urban Network Traffic Simulations: TRAF-NETSIM Program. Journal of transportation engineering. 1990;116(6):734-43.
Abedini M. TRAF-NETSIM Calibration for Iran Signalized Intersections. Tehran, Iran: University of Tehran; 1999.
Banks J. Discrete-event System Simulation: Prentice Hall; 2010.
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).