Traffic Efficiency Evaluation of Elliptical Roundabout Compared with Modern and Turbo Roundabouts Considering Traffic Signal Control
This paper compared the performance of elliptical roundabout with turbo and modern roundabouts. It considers the effects of increasing the central island radius and speed limit on delay and capacity. Three types of roundabouts (modern, turbo and elliptical roundabouts) with different numbers of lanes (single lane, two-lane and three-lane) were designed. Unsignalized and signalized controls were applied for these roundabouts. The robustness of the designed roundabouts was investigated for saturated and unsaturated flow conditions. Based on the obtained results, increasing the central island radius had both positive and negative effects on delay and capacity. However, a positive effect on these variables was observed in all roundabouts when increasing the speed limit. In unsignalized and signalized control under unsaturated flow conditions, a modern roundabout had lower delay time than an elliptical roundabout. Moreover, in saturated flow, the elliptical roundabout had the best performance in terms of delay. Overall, in comparison with the turbo roundabouts, modern and elliptical roundabouts had the highest capacities in unsignalized and signalized controls. This study can provide useful information for engineers who decide to design a roundabout.
Chang I, Ahn SY, Hahn JS. Analysis of delay reduction effects on modern roundabouts according to the entry traffic volume. KSCE Journal of Civil Engineering. 2013;17(7):1782-1787.
Fortuijn L. Turbo roundabouts: design principles and safety performance. Transportation Research Record. 2009;2096:16-24.
Mehmood A, Easa SM. Optimizing geometric design of roundabouts: multi-objective analysis. Canadian Journal of Civil Engineering. 2006;33(1):29-40.
Easa SM, Mehmood A. Optimizing geometric design of single-lane roundabouts: consistency analysis. Canadian Journal of Civil Engineering. 2004;31(6):1024-1038.
Mauro R, Cattani M. Functional and economic evaluations for choosing road intersection layout. PROMET - Traffic & Transportation. 2012;24(5):441-448.
Tollazzi T, Giovanni T, Guerrieri M, Campisi T. Environmental, functional and economic criteria for comparing “target roundabouts” with one- or two-level roundabout intersections. Transportation Research Part D: Transport and Environment. 2015;34:330-344.
Zhang L, Du W, Liu S, Zhang S. Dynamic vehicular delay analysis between a roundabout and a pre-timed traffic signal. In Eighth International Conference of Chinese Logistics and Transportation Professionals (ICCLTP); 2009; Chengdu, China: American Society of Civil Engineers. p. 3982-3988.
Gagnon C, Sadek A, Touchette A, Smith M. Calibration potential of common analytical and microsimulation roundabout models: New England case study. Transportation Research Record. 2009;2071:77-86.
Qu X, Ren L, Wang S, Oh E. Estimation of entry capacity for single-lane modern roundabouts: case study in Queensland, Australia. Journal of Transportation Engineering. 2014 July;140(7).
Sisiopiku VP, Oh HU. Evaluation of roundabout performance using SIDRA. Journal of Transportation Engineering. 2001 March/April;127(2):143-150.
Al-Madani HMN. Capacity of large dual and triple-lanes roundabouts during heavy demand conditions. Arabian Journal for Science and Engineering. 2013 March;38(3):491-505.
Yap YH, Gibson HM, Waterson BJ. An international review of roundabout capacity modelling. Transport Reviews. 2013;33(5):593–616.
Kim S, Choi J. Safety analysis of roundabout designs based on geometric and speed characteristics. KSCE Journal of Civil Engineering. 2013;17(6):1446-1454.
Tracz M, Chodur J. Performance and Safety Roundabouts with Traffic Signals. Procedia - Social and Behavioral Sciences. 2012;53:789-800.
Bai Y, Xue K, Wang T. Association of signal-controlled method at roundabout and capacity. In Ninth International Conference of Chinese Transportation Professionals (ICCTP); 2009; Harbin, China: American Society of Civil Engineers. p. 1-12.
Maher M. The optimization of signal settings on a signalized roundabout using the cross-entropy method. Computer-Aided Civil and Infrastructure Engineering. 2008;23(2):76-85.
Silva AB, Vasconcelos L, Santos S. Moving from conventional roundabouts to turbo-roundabouts. Procedia - Social and Behavioral Sciences. 2014;111:137-146.
Mauro R, Branco F. Comparative analysis of compact multilane roundabouts and turbo-roundabouts. Journal of Transportation Engineering. 2010;136(4):316-322.
Corriere F, Guerrieri M. Performance Analysis of Basic Turbo-Roundabouts in Urban Context. Procedia - Social and Behavioral Sciences. 2012;53:622-632.
Engelsman JC, Uken M. Turbo roundabouts as an alternative to two lane roundabouts. In 26th Annual Southern African Transport Conference 2007; 2007; Pretoria, South Africa. p. 581-589.
Giuffrè O, Grana A, Marino S. Turbo-roundabouts vs roundabouts performance level. Procedia - Social and Behavioral Sciences. 2012;53:590-600.
Hoek RM. Signalized turbo roundabouts: a study into the applicability of traffic signals on turbo roundabouts. Master thesis. Civil Engineering and Geosciences, Transport & Planning; 2013.
Tollazzi T, Renčelj M, Turnšek S. New type of roundabout: roundabout with "depressed" lanes for right turning - "flower roundabout". Promet – Traffic & Transportation. 2011;23(5):353-358.
Robinson, B W. and Rodegerdts, L. Roundabouts: an informational guide, Report FHWA-RD-00-067, Federal Highway Administration, Washington D.C., USA. 2000.
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