Modeling Right-Turn Blockage and Approach Capacity at Signalized Intersections with Channelized Right-Turn Lanes
Publication: Journal of Transportation Engineering, Part A: Systems
Volume 143, Issue 2
Abstract
Right-turn channelization is used to improve the capacity at busy intersections with a lot of right-turns. However, under heavy traffic conditions the through lane vehicles might backup and block the channelization lane. This will affect the discharge rate of right-turning vehicles and reduce the approach capacity. If the right-turn channelization gets blocked frequently, its advantage is neglected and serious capacity problems can be overlooked. This issue is not addressed in the Highway Capacity Manual (HCM), and no separate model is provided to estimate the capacity of approaches with channelized right-turn lanes. Using conventional methods for estimating the capacity without considering the effect of potential blockage would result in overestimation of the approach capacity. This paper presents a probabilistic capacity model for signalized intersections with channelized right-turn lanes considering the possibility of the right-turn vehicles being blocked from accessing the channelization lane. The capacity model was developed as a function of the short-lane section length and the proportion of right-turn traffic by taking into account the probability of blockage. Subsequently, a model was developed to estimate the probability of blockage with respect to the possible residual queue. The proposed capacity model and the blockage probability model were validated on the basis of VISSIM simulations. For operational purposes, the recommended lengths of the short-lane section were developed to prevent blockage at a certain threshold. The recommended lengths would be useful in evaluating adequacy of the current lengths, identifying the options of extending the short-lane section length, or changing signal timing to reduce the likelihood of blockage.
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Acknowledgments
Special thanks are expressed to Dr. Reed Gibby and Dr. Anna Panorska for their valuable advice and input. The authors are indebted to Dr. Kyle Bradford for his assistance and helpful suggestions in the course of this study.
References
AASHTO. (2011). “Policy on geometric design of highways and streets.” Washington, DC.
Akcelik, R. (1998). “A queue model for HCM 2000.” ARRB Transport Research, Vermont South, Australia.
Farivar, S. (2015). “Modeling capacity and delay at signalized intersections with channelized right-turn lanes considering the impact of blockage.” Ph.D. dissertation, Univ. of Nevada, Reno, NV.
HCM (Highway Capacity Manual). (2000). “Transportation research board of the national academies.” Washington, DC.
HCM (Highway Capacity Manual). (2010). “Transportation research board of the national academies.” Washington, DC.
Kikuchi, S., Chakroborty, P., and Vukadinovic, K. (1993). “Lengths of left-turn lanes at signalized intersections.” Transp. Res. Rec., 1385, 162–171.
Kikuchi, S., Kii, M., and Chakroborty, P. (2004). “Lengths of double or dual left-turn lanes.” Transp. Res. Rec., 1881, 72–78.
Kikuchi, S., and Kronprasert, N. (2008). “Determining the length of the right-turn lane at a signalized intersection.” Transp. Res. Rec., 2060, 19–28.
Kikuchi, S., and Kronprasert, N. (2010). “Determining lengths of left-turn lanes at signalized intersections under different left-turn signal schemes.” Transp. Res. Rec., 2195, 70–81.
Kikuchi, S., Kronprasert, N., and Kii, M. (2007). “Lengths of turn lanes on intersection approaches: Three-branch fork lanes-left-turn, through, and right-turn lanes.” Transp. Res. Rec., 2023, 92–101.
Macfarlane, G. S., Saito, M., and Schultz, G. G. (2011). “Delay underestimation at free right-turn channelized intersections.” Procedia—Social and Behavioral Sciences, 16 (6th Int. Symp. on Highway Capacity and Quality of Service), Elsevier, Amsterdam, Netherlands, 560–567.
Newell, G. F. (1965). “Approximation methods for queues with application to the fixed-cycle traffic light.” Soc. Ind. Appl. Math. (siam), 7(2), 223–240.
Olszewski, P. S. (1990). “Modeling of queue probability distribution at traffic signals.” Proc., 11th Int. Symp. on Transportation and Traffic Theory, Yokohama, Japan, 569–588.
Oppenlander, J. C., and Oppenlander, J. E. (1999). “Storage requirements for signalized intersection approaches—Uniform arrivals.” Inst. Transp. Eng., 66(2), 27–30.
Oppenlander, J. C., and Oppenlander, J. E. (2002). “Simulation of left-turn storage lengths without separate signal phase.” Inst. Transp. Eng., 72(5), 34–38.
Qi, Y., Yu, L., Azimi, M., and Guo, L. (2007). “Determination of storage lengths of left-turn lanes at signalized intersections.” Transp. Res. Rec., 2023, 102–111.
Qsei-Asamoah, A., Kulshrestha, A., Washburn, S., and Yin, Y. (2010). “Impact of left-turn spillover on through movement discharge at signalized intersections.” Transp. Res. Rec., 2173, 80–88.
Reynolds, W. L., Rouphail, N., and Zhou, X. (2011). “Turn pocket blockage and spillback models: Applications to signal timing and capacity analysis.” Transp. Res. Rec., 2259, 112–122.
Roess, R. P., Prassas, E. S., and McShane, W. R. (2004). Traffic engineering, 3rd Ed., Pearson Prentice Hall, Upper Saddle River, NJ.
Tarko, A. P. (2001). “Predicting right turns on red.” Transp. Res. Rec., 1776, 138–142.
Tian, Z., Kyte, M., Vandehey, M., Kittelson, W., and Robinson, B. (2001). “Simulation based study on traffic operational characteristics at all-way stop-controlled intersections.” Transp. Res. Rec., 1776, 75–81.
Tian, Z., Urbanik, T., Engelbrecht, R., and Balke, K. (2002). “Variations on capacity and delay estimates from microscopic simulation models.” Transp. Res. Rec., 1802, 23–31.
Tian, Z., and Wu, N. (2006). “Probabilistic model for signalized intersection capacity with a short right-turn lane.” J. Transp. Eng., 205–212.
Wu, N. (2011). “Modeling blockage probability and capacity of shared lanes at signalized intersections.” Procedia—Social and Behavioral Sciences, 16 (6th Int. Symp. on Highway Capacity and Quality of Service), Elsevier, Amsterdam, Netherlands, 481–491.
Yin, K., Zhang, Y., and Wang, B. X. (2011). “Modeling delay during heavy traffic for signalized intersections with short left-turn bays.” Transp. Res. Rec., 2257, 103–110.
Zhang, Y., and Tong, J. (2008). “Modeling left-turn blockage and capacity at signalized intersection with short left-turn bay.” Transp. Res. Rec., 2071, 71–76.
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Published In
Journal of Transportation Engineering, Part A: Systems
Volume 143 • Issue 2 • February 2017
Copyright
©2016 American Society of Civil Engineers.
History
Received: Nov 3, 2015
Accepted: Sep 14, 2016
Published online: Nov 18, 2016
Published in print: Feb 1, 2017
Discussion open until: Apr 18, 2017
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