Citation

Hashim IH, Ragab M, Asar GM. Int. J. Traffic Transp. Eng. (Belgrade) 2017; 7(1): 37-51.

Copyright

(Copyright © 2017, City Net Scientific Research Center, Faculty of Transport and Traffic Engineering, University of Belgrade)

DOI

10.7708/ijtte.2017.7(1).03

PMID

unavailable

Abstract

Road intersections force vehicles to slow down and stop in varying patterns and contribute to the increase in vehicular emissions. The main aim of this paper is to evaluate the operational and environmental performance of median U-turn design. Also, it aims to compare this design with conventional three-leg and signalized three-leg intersections in terms of average delay, fuel consumption and air emissions including carbon monoxide (CO), nitrogen oxides (NOX) and hydrocarbons (HC). The microscopic traffic simulation model VISSIM was used to model and analyze the three designs under a wide range of balanced and unbalanced flow conditions. The results indicated that, the median U-turn (MUT) design exhibited slightly lower delays than conventional three-leg intersection at balanced volume scenarios, up to approximately 1250 veh/hr/approach. After this volume level, the median U-turn (MUT) design exhibited higher delays than three-leg intersection. Also, the median U-turn (MUT) design exhibited lower air emissions and fuel consumption than other intersections at all balanced volume scenarios. In addition, under unbalanced volume scenarios, the average delay, air emissions and fuel consumption increased with the increase of main and/or cross street volumes for the median U-turn (MUT) design.

Language: en