Abstract
In the current version of the Highway Capacity Manual (HCM-6), the equal capacity passenger car equivalency (EC-PCE) method is used to account for the effect of trucks for capacity analyses. The EC-PCEs for freeway segments were estimated using a microsimulation-based methodology where a nonlinear regression model (NLRM) with 15 model parameters was used to develop capacity adjustment factor (CAF) models using the microsimulation data as input. The objective of this paper is to introduce a simpler nonlinear regression model with 6 model parameters that can be used for the estimation of CAF values and EC-PCE values for freeway and multilane highway segments. It was found that the proposed model can readily substitute the original model with little loss in fidelity. The CAF formulae developed in this paper can be used to calculate EC-PCE values directly, obviating the need for the HCM-6 EC-PCE tables. Equally important, the simpler models provide the user with a better understanding of the trade-offs between capacity, CAF, and EC-PCE values and the parameters that affect them.
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Data Availability Statement
Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
The authors would like to thank the Nebraska Transportation Center for providing the necessary technical tools used in this research. In addition, the authors would like to acknowledge the Fulbright foundation who supported Dr. Hurtado-Beltran’s Ph.D. work at the University of Nebraska-Lincoln. The contents of this paper reflect the views of the authors, who are responsible for the facts and the accuracy of the information presented herein and are not necessarily representative of any group or agency. The authors confirm contribution to the paper as follows: study conception and design: AH, LR; data collection: AH, LR; analysis and interpretation of results: AH, LR; and draft manuscript preparation: AH, LR. All authors reviewed the results and approved the final version of the manuscript.
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Journal of Transportation Engineering, Part A: Systems
Volume 148 • Issue 1 • January 2022
Copyright
© 2021 American Society of Civil Engineers.
History
Received: Mar 1, 2021
Accepted: Sep 17, 2021
Published online: Nov 12, 2021
Published in print: Jan 1, 2022
Discussion open until: Apr 12, 2022
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- Efstathios Bouhouras, Konstantina Kikeni, Athanasios Siginos, Apostolos Vouitsis, Konstantina Voulgari, Socrates Basbas, Is It Necessary to Calculate Passenger Car Equivalent Value for Commercial Vehicles in Urban Areas?, Smart Energy for Smart Transport, 10.1007/978-3-031-23721-8_102, (1266-1277), (2023).