1. bookVolume 17 (2021): Issue 1 (June 2021)
Journal Details
License
Format
Journal
First Published
30 May 2014
Publication timeframe
2 times per year
Languages
English
access type Open Access

Capacity Model for Single-Lane Minor Entry at Turbo-Roundabouts

Published Online: 22 Jun 2021
Page range: 318 - 326
Journal Details
License
Format
Journal
First Published
30 May 2014
Publication timeframe
2 times per year
Languages
English
Abstract

Spirally arranged and physically separated traffic lanes in the circulatory carriageway of turbo-roundabouts force drivers to choose a particular entry lane and, subsequently, a circulatory traffic lane according to their intended destination. This specificity is taken into account in theoretical capacity models for two-lane turbo-roundabout entries typically evaluated by the lane-by-lane approach. Nevertheless, this specific path of movements is not considered in the most widely used capacity models for single-lane minor entries at oval turbo-roundabouts. In these models, only one entering traffic flow conflicted by two circulating traffic flows in front of the entry is considered. However, the entering traffic flow presents a mixed traffic flow of two movements (right-turning movement and left-turning and through movement) with different capacities due to different number of conflicting traffic streams and traffic volumes allocated into the outer and the inner circulatory lane. This fact is included in the capacity estimation for a single-lane minor entry presented in the article using the existing capacity formula for the mixed traffic flow on a shared minor lane at unsignalized intersections. The entry capacity reflects the proportion of the right-turning movement within a shared entry lane as well as the specific allocation of circulating traffic flow into the outer and the inner circulatory lane. This entry capacity is about 10 % to 30 % higher compared to a single-lane entry capacity estimated according to commonly used models described in the article. Higher entry capacity in a higher proportion of the right-turning traffic within mixed entry traffic flow is confirmed also by the results of average delays estimated by the theoretical delay model and microsimulation.

Keywords

[1] Highway Capacity Manual, HCM2010, Vol.3, TRB, Washington D.C., U.S., 2010. Search in Google Scholar

[2] GUERRIERI, M. - CORRIERE, F. - TICALI, D.: Turbo-Roundabouts: A Model to Evaluate Capacity, Delays, Queues and Level of Service. European Journal of Scientific Research, Vol. 92, No. 2, December, 2012, pp. 267-282. Search in Google Scholar

[3] MACIOSZEK, E.: The application of HCM 2010 in the determination of capacity of traffic lanes at turbo roundabout entries. Transport Problems, Vol. 11, Iss. 3, 2016, pp. 77-89. Search in Google Scholar

[4] WU, N.: An Universal Formula for Calculating Capacity at Roundabouts. Arbeitsblaetter, Institute for Traffic Engineering, Ruhr-University Bochum, No.13, 1997. Search in Google Scholar

[5] TANNER, J.C.: The capacity of an uncontrolled intersection. Biometrica, Vol. 54 (3 and 4), 1967, pp. 657-658. Search in Google Scholar

[6] TP102 Design of Turbo-roundabouts (in Slovak). Technical regulations. Ministry of Transport, Construction and Regional Development, Bratislava, 2015. Search in Google Scholar

[7] FORTUIJN, L.G.H. - HARTE, V.F.: Meerstrooksrotondes:verkenning van nieuwe vormen (Multilane rounadabouts: An exploration of new forms, in Duch), Verkeerskundige werkdagen 1997, CROW, Ede. Search in Google Scholar

[8] BOVY, H. - DIETRICH, K. - HARMANN, A.: Guide Suisse des Giratoires. Lausanne, Switzeraland, p. 75 (see summary in Strasse und Verkehrstechnik, 3, pp. 137-139), 1991. Search in Google Scholar

[9] FORTUIJN, L.G.H.: Turbo Roundabouts: Estimation of Capacity. TRR: Journal of the transportation Research Board 2009, 2130, pp. 83-92. Search in Google Scholar

[10] GALLELLI, V. - VAIANA, R.: Safety Improvements by Converting a Standard Roundabout with Unbalanced Flow Distribution into an Egg Turbo Roundabout: Simulation Approach to a Case Study. Sustainability 2019, 11, 466. Search in Google Scholar

[11] GALLELLI, V. - IUELE T. - VAIANA, R.: Conversion of a semi-two lanes roundabout into a turbo-roundabout: a performance comparison. The 7th International Conference on Ambient Systems, Networks and Technologies, Vol. 83, 2016, pp. 393-400. Search in Google Scholar

[12] KRIVDA, V. - PETRU, J. - MACHA, D. - PLOCOVA K. - FIBICH, D.: An Analysis of Traffic Conficts as a Tool for Sustinable Road Transport. Sustainability, 12(17), 2020, 7198. Search in Google Scholar

[13] ŠARIĆ, A. - LOVRIĆ, I.: Multi-lane Roundabout Capacity Evaluation, Frontiers in Built Environment, 2017. Search in Google Scholar

[14] BRILON, W. - BONDZIO, L. - WEISER, F.: Experiences with Turbo-Roundabouts in Germany. 5th Rural Roads Design Meeting, Copenhagen, 2014. Search in Google Scholar

[15] KOCIANOVA, A.: Capacity limits of basic turbo-roundabouts. Communications, Vol. 18, Iss. 4, 2016, pp. 90-98. Search in Google Scholar

[16] HAGRING, O.: A further generalization of Tanner´s formula. Transportation Research Part B: Methodological, 32 (6), 1998, pp. 423-429. Search in Google Scholar

[17] GIUFFRÈ, O. - GRANÀ, A. - MARINO, S.: Comparing performances of turbo-roundabouts and double-lane roundabouts. Modern Applied Science, Vol. 6, No. 10, 2012, pp. 70-79. Search in Google Scholar

[18] GRANÀ, A. - GIUFFRÈ, T. - MACIOSZEK, E. - ACUTO, F.: Estimation of Passenger Car Equivalents for Two-Lane and Turbo Roundabouts Using AIMSUN. Frontiers in Built Environment/Transportation and Transit system, Vol. 6, 2020. Search in Google Scholar

[19] PITLOVA, E. - KOCIANOVA, A.: Case study: capacity characteristics comparison of single-lane roundabout and turbo-roundabouts. Proceedings of TRANSCOM 2017, International scientific conference on sustainable modern and safe transport, 2017, pp. 701-706. Search in Google Scholar

[20] SILVA, A. B. - VASCONCELOS, A. L. P. - SANTOS, S.: Moving from Convential Roundabouts to Turbo-Roundabouts. Procedia – Social and Behavioral Sciences, No. 111, 2013, pp. 137-146. Search in Google Scholar

[21] VASCONCELOS, A. L. P. - SILVA, A. B. - SECO, A. J. M.: Capacity of Normal and Turboroundabouts: Comparative Analysis. Proc. of the Institution of Civil Engineers (ICE) – Transport, Vol. 167, Iss. 2, 2014, pp. 88-99. Search in Google Scholar

[22] TANNER, J. C.: A theoretical analysis of delay At an Uncontrolled Intersections. Biometrica, 49 (1-2), 1962, pp.163-170. Search in Google Scholar

[23] MAURO, R. - BRANCO, F.: Comparative Analysis of Compact Multilane Roundabouts and Turbo-Roundabouts. Journal of Transportation Engineering 136, 2010, pp. 316-322. Search in Google Scholar

[24] WU, N.: Capacity of Shared/Short Lanes at Unsignalized Intersections. Transportation Research, A33, Iss. 3-4, Elsevier Science Ltd., New York, Tokyo, Oxford, 1999, pp. 255-274. Search in Google Scholar

[25] WU, N. - BRILON, W.: Delays of shared-short lanes at unsignalized intersections. Journal of the Transportation Research Board, TRB, Vol. 2673, Iss. 8, 2019. Search in Google Scholar

[26] KOCIANOVA, A. - DRLICIAK, M. - PITLOVA, E.: Influence of roundabout capacity enhancement on emission production. Proceedings of the International Conference Building up Efficient and Sustainable Transport Infrastructure, BESTInfra 2017. Search in Google Scholar

[27] PETRU, J. - KRIVDA, V.: An Analysis of Turbo Roundabouts from the Perspective of Sustainability of Road Transportation. Sustainability, 13, 2021, 2119. Search in Google Scholar

Recommended articles from Trend MD

Plan your remote conference with Sciendo