Roundabout Safety Benefits, Design Considerations and Safety Evaluation Techniques
A Review
Main Article Content
Abstract
Roundabouts are increasingly replacing conventional signalized intersections due to their potential to enhance traffic safety and operational efficiency. This paper examines and reviews the safety benefits, design considerations, and evaluation methods for roundabouts. Studies consistently show significant reductions in crashes at roundabouts relative to other at-grade intersection control systems, particularly severe injury crashes, with reductions ranging from 37% to 88%. Roundabouts reduce conflict points, lower vehicle speeds, and improve safety for both motorized and vulnerable road users. The methodology for this paper involved a comprehensive review of literature on roundabout design and safety evaluation techniques. Data from global studies were analyzed to identify key design elements such as geometric layout, signage, and pedestrian provisions, which contribute to roundabout safety. Various safety evaluation methods, including crash data analysis, traffic conflict techniques, and surrogate safety measures, were also assessed for their effectiveness in evaluating roundabout performance. Findings indicate that proper geometric design, clear signage, and the use of innovative features like right-turn bypass lanes and roundabout metering systems can enhance safety and traffic flow. Based on these findings, the paper recommends integrating these design elements, prioritizing the safety of vulnerable users, and utilizing advanced safety evaluation techniques, including simulation modelling and intelligent transportation systems (ITS) to further optimize roundabout performance.
Article Details
Copyright (c) 2024 Engr. Ahmad Batari, Dr. M. N. Ibrahim (Author)
This work is licensed under a Creative Commons Attribution 4.0 International License.
Engr. Ahmad Batari, Department of Civil Engineering, Abubakar Tafawa Balewa University, Bauchi
PhD Student, Department of Civil Engineering, Bayero University, Kano and a Lecturer, Department of Civil Engineering, Abubakar Tafawa Balewa University Bauchi, Nigeria.
Dr. M. N. Ibrahim, Department of Civil Engineering, Bayero University, Kano
Reader, and Head, Department of Civil Engineering, Bayero University, Kano
Adeke, P. T., Etika, A., & Atoo, A. A. (2020). Capacity and Performance Assessment of Wurukum Roundabout In Makurdi Metropolis: A Comparative Study Using Arcady And Sidra Intersection Software. Arid Zone Journal of Engineering, Technology & Environment, 16(2), 309–320.
Ahac, S., & Dragcevic, V. (2021). Geometric Design of Suburban Roundabouts. Encyclopedia, 1, 720–743. https://doi.org/https://doi.org/10.3390/encyclopedia1030056
Ahac, S., & Kipa, P. (2022). Investigation of the clear sight areas on suburban roundabouts. Infrastructure Design and Traffic Safety. 7th International Conference on Road and Rail Unfrastructure - CETRA 2022, 11-13 May. https://doi.org/10.5592/CO/CETRA.2022.1348
Ahmad, A., & Rastogi, R. (2019). Calibrating HCM model for roundabout entry capacity under heterogeneous traffic. Journal of Modern Transportation, 27(4), 293–305. https://doi.org/10.1007/s40534-019-00194-7
Akcelik, R., Shirke, C., Basley, M., Espada, I., & Billinghurst, D. (2022). A Comparative Analysis of Exponential and Linear Roundabout Capacity Models Using HCM Research Data (Issue May).
Akçelik, R., Shirke, C., Besley, M., Espada, I., & Billinghurst, D. (2022). A Comparative Analysis of Exponential and Linear Roundabout Capacity Models Using HCM Research Data. In Technical Note (Issue May). www.sidrasolutions.com
Al Bashaireh, R., Zohdy, M., & Sabeeh, V. (2005). National Roundabout Conference. NCRHP 3-65: DATA COLLECTION AND EXTRACTION, November 2004, 71–76. https://doi.org/10.1145/3404663.3404686
Al Hasanat, H., & Janos, J. (2023). Development of Roundabouts Empirical Capacity Model - Case Study of Hungary. Scientific Journal of Silesian University of Technology. Series Transport, 120(May), 5–17. https://doi.org/10.20858/sjsutst.2023.120.1
Aldohuky, M. H. A. (2023). PERFORMANCE ANALYSİS OF ROUNDABOUT JUNCTİON İN DUHOK WİTH PROPOSED SİGNALİZED ONE THROUGH (Issue May). SAKARYA UNIVERSITY GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES.
Alkaissi, Z. A. (2022). Traffic Simulation of Urban Street to Estimate Capacity. Journal of Engineering, 28(4), 51–63. https://doi.org/10.31026/j.eng.2022.04.04
Alkaissi, Z. A., & Kamoona, W. A. (2021). Influence of Roadside Impedance on Speed and Capacity of Urban Streets. IOP Conference Series: Materials Science and Engineering, 1090(1), 012121. https://doi.org/10.1088/1757-899x/1090/1/012121
Alkheder, S., Al-rukaibi, F., & Al-faresi, A. (2020). Driver behavior at Kuwait roundabouts and its performance evaluation. IATSS Research, 44(4), 272–284. https://doi.org/10.1016/j.iatssr.2020.03.004
Alshannaq, M., & Imam, R. (2020). Evaluating the safety performance of roundabouts. Transport Problems, 15(1), 141–152. https://doi.org/10.21307/TP-2020-013
Anagnostopoulos, A., Kehagia, F., & Aretoulis, G. N. (2022). Application of Artificial Neural Network for Modelling and Predicting Roundabout Capacity. ’8th Road Safety and Simulation International Conference, Athens, Greece8-10 June 2022, June.
Anagnostopoulos, A., Kehagia, F., Damaskou, E., Mouratidis, A., & Aretoulis, G. (2021). Predicting Roundabout Lane Capacity using Artificial Neural Networks. Journal of Engineering Science and Technology Review, 14(5). https://doi.org/10.25103/jestr.145.24
Anai, K., Yokota, T., & Matsumoto, T. (2024). Method of predicting road traffic noise around small-scale roundabouts in Japan. Acoustical Science and Technology, 45(2), 69–80. https://doi.org/10.1250/ast.e23.17
Araslan, M., Kumar, K., Kumar, V., Ansari, M. A., & Raza, H. (2022). Capacity of Roundabout, Performance & Analysis - A Review. Interantional Journal of Scientific Research in Engineering and Management, 06(12), 10–13. https://doi.org/10.55041/ijsrem17292
ASCE. (2021). Modern roundabouts boost traffic safety and efficiency. American Society of Engineers. https://www.asce.org/publications-and-news/civil-engineering-source/civil-engineering-magazine/issues/magazine-issue/article/2021/03/modern-roundabouts-boost-traffic-safety-and-efficiency
Awadalla, D. M. M., & Albuquerque, D. F. D. B. (2021). Identification of Risk Factors Associated with Fatal Intersection Crashes and Assessment of the In-Service Safety Performance of Signalized Intersections and Roundabouts in Abu Dhabi. Safety, 7(4). https://doi.org/10.3390/SAFETY7040069
Bari, C., & Dhamaniya, A. (2022). Reduction in Entry Capacity of Roundabout Under the Influence of Pedestrians in Mixed Traffic Conditions. Communications - Scientific Letters of the University of Žilina, 24(4), D201–D214. https://doi.org/10.26552/com.C.2022.4.D201-D214
Bhattarai, N. (2003). Proactive safety analysis using roadside LiDAR based vehicle trajectory data. (Issue December 2023). Texas Tech University.
Brewer, M. A., Zhou, H. “Tracy,” Tydlacka, J., & Florence, D. (2023). Operational Performance of Roundabouts at High-Speed and Rural Locations. Transportation Research Record, 2677(12), 144–157. https://doi.org/10.1177/03611981231167155
Chen, R. (2018). Microscopic simulation and evaluation of the roundabout capacity model in highway capacity manual. Msc Thesis ,The University of Minnesota, January.
Chen, R., & Hourdos, J. (2018). Evaluation of the roundabout capacity model in HCM6 edition and HCM 2010 on a multilane roundabout. Transportation Research Record, 2672(15), 23–34. https://doi.org/10.1177/0361198118794287
Čudina Ivančev, A., Ahac, M., Ahac, S., & Dragčević, V. (2023). Comparison of Single-Lane Roundabout Entry Degree of Saturation Estimations from Analytical and Regression Models. Algorithms, 16(3). https://doi.org/10.3390/a16030164
Deveaux, D., Higuchi, T., Uçar, S., Härri, J., & Altintas, O. (2024). Role of context in determining transfer of risk knowledge in roundabouts. Computer Communications, 213(November 2022), 111–134. https://doi.org/10.1016/j.comcom.2023.10.016
Distefano, N., & Leonardi, S. (2019). Experimental investigation of the effect of roundabouts on noise emission level from motor vehicles. Noise Control Engineering Journal, 67(4), 282–294. https://doi.org/10.3397/1/376725
Ederer, D. J., Panik, R. T., Botchwey, N., & Watkins, K. (2023). The Safe Systems Pyramid: A new framework for traffic safety. Transportation Research Interdisciplinary Perspectives, 21(May), 100905. https://doi.org/10.1016/j.trip.2023.100905
El Ganaoui-Mourlan, O., Camp, S., Verhas, C., Pollet, N., Ortega, B., & Robic, B. (2023). Traffic Manager Development for a Roundabout Crossed by Autonomous and Connected Vehicles Using V2I Architecture. Sustainability (Switzerland), 15(12). https://doi.org/10.3390/su15129247
Elzaher, A. H., & Albuquerque, D. F. D. B. (2021). Signalized Intersections and Roundabouts: An In-Service Safety Performance Evaluation in Abu Dhabi. Transportation Research Procedia, 52(2020), 268–275. https://doi.org/10.1016/j.trpro.2021.01.031
Farman Majeed Salam, & Majid, A. prof. D. H. M. (2022). Evaluation of Capacity and Level of Service for Heterogeneous Traffic of Urban Multi-Lane Highways. Construction, 2(2), 31–38. https://doi.org/10.15282/construction.v2i2.8609
Fathullah, H. S., Majid, H. M., Ahmed, C. H., Sourkan, S. H., Ismael, K. S., & Abdulsamad, B. Z. (2023). Traffic Circulation Efficiency of Elliptical Roundabouts. Aro-the Scientific Journal of Koya University, 11(2), 65–72. https://doi.org/10.14500/aro.11150
Fernandes, P., Tomás, R., Acuto, F., Pascale, A., Bahmankhah, B., Guarnaccia, C., Granà, A., & Coelho, M. C. (2020). Impacts of roundabouts in suburban areas on congestion-specific vehicle speed profiles, pollutant and noise emissions: An empirical analysis. Sustainable Cities and Society, 62(November 2019). https://doi.org/10.1016/j.scs.2020.102386
FHWA. (2022). Highway Safety Programs. Roundabouts. https://highways.dot.gov/safety/intersection-safety/intersection-types/roundabouts
Fromme, V. (2010). Research on roundabouts. Sides 1.
Gathungu, D. (2022). Evaluating Unsignalized Circular Roundabout Capacity Using Macroscopic Traffic Flow Model. April.
Gazder, U., Ahmed, A., Abdulhusain, B. H., Mohamed, A. H., & Ratrout, N. (2023). Estimating the severity levels of road traffic crashes in Bahrain with crash costs estimated with different approaches. Digital Transportation and Safety, 2(4), 278–283. https://doi.org/10.48130/dts-2023-0023
Giuffrè, O., Granà, A., & Tumminello, M. L. (2017a). Exploring the uncertainty in capacity estimation at roundabouts. European Transport Research Review, 9(2), 1–13. https://doi.org/10.1007/S12544-017-0238-8/FIGURES/10
Giuffrè, O., Granà, A., & Tumminello, M. L. (2017b). Exploring the uncertainty in capacity estimation at roundabouts. European Transport Research Review, 9(2). https://doi.org/10.1007/s12544-017-0238-8
Gracanin, D., Ruskic, N., Pavlica, T., Maric, M., & Ciric Lalic, D. (2023). Simulation Modelling of Pedestrians Influence on the Roundabout Capacity. International Journal of Simulation Modelling, 22(3), 474–484. https://doi.org/10.2507/IJSIMM22-3-656
Guerrieri, M. (2023). A theoretical model for evaluating the impact of connected and autonomous vehicles on the operational performance of turbo roundabouts. International Journal of Transportation Science and Technology, xxxx. https://doi.org/10.1016/j.ijtst.2023.05.001
Guerrieri, M., Corriere, F., Rizzo, G., Lo Casto, B., & Scaccianoce, G. (2015). Improving the sustainability of transportation: Environmental and functional benefits of right turn by-pass lanes at roundabouts. Sustainability (Switzerland), 7(5), 5838–5856. https://doi.org/10.3390/su7055838
Guo, R., Wu, J., Ji, F., Wang, W., & Yin, Y. (2024). Analysis of traffic safety in airport aircraft activity areas based on bayesian networks and fault trees. Digital Transportation and Safety, 3(1), 8–18. https://doi.org/10.48130/dts-0024-0002
Han, I. (2022). Safety analysis of roundabouts and avoidance of conflicts for intersection-advanced driver assistance systems Safety analysis of roundabouts and avoidance of conflicts for intersection-advanced driver assistance systems. Cogent Engineering, 9(1). https://doi.org/10.1080/23311916.2022.2112813
Hétu, M. (2000). ROUNDABOUT PERFORMANCE SAFETY, CAPACITY AND SIGNING. Engineering. https://www.semanticscholar.org/paper/ROUNDABOUT-PERFORMANCE-SAFETY%2C-CAPACITY-AND-SIGNING-Hétu/a89c36639930c891c4f402d5944a19dfeb0490bc
Hossain, M. M., & Rahman, M. A. (2023). Understanding the potential key risk factors associated with teen driver crashes in the United States: a literature review. Digital Transportation and Safety, 2(4), 268–277. https://doi.org/10.48130/dts-2023-0022
Kácovský, J. J. K. T. P. (2019). Examination of Logical Trends in Traffic Conflicts and Traffic Accidents in the Context of Road Safety at Roundabouts. Smart City Symposium Prague (SCSP), pp 1-6. https://doi.org/10.1109/SCSP.2019.8805675
Kadeha, C. (2016). Influence of Traffic and Geometric features on safety and operations of roundabouts. 88.
Kalašová, A., Kubíková, S. S., & Harantová, V. (2021). Modelling of the traffic flow basic characteristics at the road network selected section. Communications - Scientific Letters of the University of Žilina, 23(1), A44–A53. https://doi.org/10.26552/com.C.2021.1.A44-A53
Karimov, N. M., Pirov, J. T., & Mikhaylov, A. Y. (2023). Critical headway and follow-up time analysis at two-lane roundabouts. E3S Web of Conferences, 403, 1–11. https://doi.org/10.1051/e3sconf/202340307015
Karkee, D., Tiwari, H., & Dhungel, S. (2023). Impact of Roundabout Metering on the Operational Performance of Roundabout: A Case Study of Jawalakhel, Nepal. Journal of Transportation Systems, 8(2), 26–33. https://doi.org/10.46610/jots.2023.v08i02.004
Karunarathne, H. K. D. T., Sandaruwan, M. A. K., Madushani, U. K. A. H., & Wickramasinghe, W. M. V. S. K. (2021). Capacity Analysis for Urban Roundabouts in Sri Lanka Using Modified SIDRA Model. Lecture Notes in Civil Engineering, 94. https://doi.org/10.1007/978-981-15-7222-7_28
Kehagia, F., Anagnostopoulos, A., Damaskou, E. P., & Mouratidis, A. (2022). An analysis on impact of geometric elements of multilane roundabouts on driver behavior. June.
Khakifirooz, M., Fathi, M., & Du, L. (2024). Reliability Assessment of Vehicle-to-Vehicle Communication Networks through Headway Distribution and Information Propagation Delay. Transportation Research Interdisciplinary Perspectives, 24(March), 101053. https://doi.org/10.1016/j.trip.2024.101053
Khan, A., Dhamaniya, A., & Arkatkar, S. (2022). Modification in Hcm Delay Model for Roundabout for Mixed Traffic Conditions - a Pilot Study. Communications - Scientific Letters of the University of Zilina, 24(2), D92–D104. https://doi.org/10.26552/com.C.2022.2.D92-D104
Khan, M. N., & Das, S. (2024). Advancing traffic safety through the safe system approach: A systematic review. Accident Analysis and Prevention, 199(February), 107518. https://doi.org/10.1016/j.aap.2024.107518
Khekare, P., Bonthu, S., Hunt, V., Helmicki, A., & Lee, K. (2022). A Case Study on Multilane Roundabout Capacity Evaluation Using Computer Vision and Deep Learning. J. Comput. Civ. Eng. ASCE, 36(3), 1–16. https://doi.org/10.1061/(ASCE)CP.1943-5487.0001007
Klobučar, M., Deluka-Tibljaš, A., Šurdonja, S., Campisi, T., & Maršanić, R. (2022). Roundabout approaching speed analyses. CETRA 7th International Conference on Road and Rail Infrastructure., September. https://doi.org/10.5592/CO/CETRA.2022.1444
Leonardi, S., & Distefano, N. (2023a). Roundabout Trajectory Planning: Integrating Human Driving Models for Autonomous Vehicles. Sustainability, 15(23), 16288. https://doi.org/10.3390/su152316288
Leonardi, S., & Distefano, N. (2023b). Turbo-Roundabouts as an Instrument for Improving the Efficiency and Safety in Urban Area: An Italian Case Study. Sustainability (Switzerland), 15(4). https://doi.org/10.3390/su15043223
Li, L., Zhang, Z., Xu, Z. G., Yang, W. C., & Lu, Q. C. (2024). The role of traffic conflicts in roundabout safety evaluation: A review. Accident Analysis and Prevention, 196(April 2023). https://doi.org/10.1016/j.aap.2023.107430
Li, Y., Ge, C., Xing, L., Yuan, C., Liu, F., & Jin, J. (2024). A hybrid deep learning framework for conflict prediction of diverse merge scenarios at roundabouts. Engineering Applications of Artificial Intelligence, 130(December 2022). https://doi.org/10.1016/j.engappai.2023.107705
Ling, L., Zhang, W., Bao, J., & Ukkusuri, S. V. (2023). Influencing factors for right turn lane crash frequency based on geographically and temporally weighted regression models. Journal of Safety Research, 86, 191–208. https://doi.org/10.1016/j.jsr.2023.05.010
Llewellyn, R. (2015). Lighting the Way: The Use of Intelligent Road Studs at Spiral-Marked Roundabouts. Engineering, Environmental Science. https://www.semanticscholar.org/paper/Lighting-the-Way%3A-The-Use-of-Intelligent-Road-Studs-Llewellyn/9b7e3e2b3a1ccdc1ed17237ad1dadab5d125825a
Mahesh, S., Ahmad, A., & Rastogi, R. (2016). An Approach for the Estimation of Entry Flows on Roundabouts. Transportation Research Procedia, 17(December 2014), 52–62. https://doi.org/10.1016/j.trpro.2016.11.060
Majid, H. M., & Jabari, H. (2023). Comparative Evaluation of Roundabout Capacities Methods for Single- lane and Multi-lane Roundabout. Journal of Engineering, 29(3), 76–97. https://doi.org/10.31026/j.eng.2023.03.06
Majid, H., & Mohammed Ali, H. (2023). Variable’s prediction of gap acceptance roundabout capacity model – Critical gap. Innovaciencia, 11(1), 1–15. https://doi.org/10.15649/2346075X.3540
Mark, J. T., & Lin, T.-L. (2018). Impact of Geometric Factors on the Capacity of Single-Lane Roundabouts: Submitted to TRB for 2018 TRB Annual Meeting Presentation. MTJ Roundabout Engineering.
Mirzahossein, H., Safari, F., & Hassannayebi, E. (2020). Estimation of highway capacity under environmental constraints vs . conventional traffic flow criteria : A case study of Tehran. Journal of Traffic and Transportation Engineering -English Edition, 8(5), 751–761. https://doi.org/10.1016/j.jtte.2020.04.006
Modupe, A., & Ben-Edigbe, J. (2024). Modelling Mixed Traffic Time Headway Distribution Induced by Bus Rapid Transit (BRT) in Cape Town, South Africa. The Open Transportation Journal, 17(1), 1–11. https://doi.org/10.2174/18744478-v17-230811-2023-4
Modupe, A. E., Fadugba, O. G., Busari, A. A., Adeboje, A. O., Aladegboye, O. J., Alejolowo, O. O., & Chukwuma, C. G. (2021). Sustainability Assessment of the Engineering Properties of Asphalt Concrete Incorporating Pulverized Snail Shell Ash as Partial Replacement for Filler. IOP Conference Series: Earth and Environmental Science, 665(1). https://doi.org/10.1088/1755-1315/665/1/012057
Mohammed Ali, H. K., & Majid, H. M. (2023). Comparative Evaluation of Roundabout Capacities Methods for Single-lane and Multi-lane Roundabout. Journal of Engineering, 29(3), 76–97. https://doi.org/10.31026/j.eng.2023.03.06
Muhammad, S., & Jamaludin, S. A. (2022). Evaluating the Performance of Traffic Flow using SIDRA for Roundabouts in. Jurnal Kejuruteraan, 34(3), 421–427. https://doi.org/10.17576/jkukm-2022-34(3)-09
Németh, B., Farkas, Z., Antal, Z., Fényes, D., & Gáspár, P. (2023). Collision-free motion control with learning features for automated vehicles in roundabouts. Transportation Research Procedia, 72(2022), 3545–3552. https://doi.org/10.1016/j.trpro.2023.11.746
Nnabuihe, U. U. (2020). Road Transport Safety in Abuja, nigeria: An Analysis Using Traffic Conflict Technique. The University of Birmingham.
Ogunkan, D. V., & Eyitola, O. O. (2022). Pattern and Characteristics of Traffic Congestion in Nigerian Metropolitan Centres : an Example of Abeokuta Metropolis. Reseach Square, 1–17. https://doi.org/https://doi.org/10.21203/rs.3.rs-2236559/v1 License:
Osei, K. K., Adams, C. A., Ackaah, W., & Oliver-Commey, Y. (2021). Signalization options to improve capacity and delay at roundabouts through microsimulation approach: A case study on arterial roadways in Ghana. Journal of Traffic and Transportation Engineering (English Edition), 8(1), 70–82. https://doi.org/10.1016/j.jtte.2019.06.003
Otto, C. G., & Okafor, P. I. (2023). Performance Analysis of Rivers State University Roundabout Under Heterogeneous Traffic Condition. 5(2), 8–18.
Pan, F., Yang, J., Zhang, L., Ma, C., Yang, J., & Zhang, P. (2023). Impact of countdown signals on traffic safety and efficiency: a review and proposal. Digital Transportation and Safety, 2(3), 200–210. https://doi.org/10.48130/dts-2023-0016
Patnaik, A. K., Agarwal, L. A., Panda, M., & Bhuyan, P. K. (2020). Entry capacity modelling of signalized roundabouts under heterogeneous traffic conditions. Transportation Letters, 12(2). https://doi.org/10.1080/19427867.2018.1533160
Pratelli, A., & Brocchini, L. (2022). Two-Geometry Roundabouts: Estimation of Capacity. Transportation Research Procedia, 64(October), 232–239. https://doi.org/10.1016/j.trpro.2022.09.028
Pratelli, A., Brocchini, L., Pratelli, A., & Brocchini, L. (2022). Two-Geometry Roundabouts : Estimation of Capacity ScienceDirect ScienceDirect ScienceDirect Two-Geometry Roundabouts : Estimation of Capacity Two-Geometry Roundabouts : Estimation of Capacity. Transportation Research Procedia, 64(October), 232–239. https://doi.org/10.1016/j.trpro.2022.09.028
Qawasmeh, B., Kwigizile, V., & Oh, J. S. (2023). Performance and safety effectiveness evaluation of mini-roundabouts in Michigan. Journal of Engineering and Applied Science, 70(1), 1–11. https://doi.org/10.1186/s44147-023-00208-6
Qie, K., Wang, J., Li, Z., & Luo, W. (2024). Recognition of occluded pedestrians from the driver’s perspective for extending sight distance and ensuring driving Safety at signal free intersections. Digital Transportation and Safety, 1–10. https://doi.org/https://doi.org/10.48130/dts-0024-0007
Qu, X., Ren, L., Wang, S., & Oh, E. (2014). Estimation of entry capacity for single-lane modern roundabouts: Case study in Queensland, Australia. Journal of Transportation Engineering, 140(7). https://doi.org/10.1061/(ASCE)TE.1943-5436.0000675
Qu, Z., Duan, Y., Song, X., Hu, H., Liu, H., & Guan, K. (2014). Capacity prediction model based on limited priority gap-acceptance theory at multilane roundabouts. Mathematical Problems in Engineering, 2014. https://doi.org/10.1155/2014/490280
Radović, D., Mohan, M., & Bogdanovic, V. (2022). Comparative Analysis of Critical Headway Estimation at Urban Single-Lane. Promet – Traffic&Transportation, 34(2), 323–326. https://doi.org/10.7307/ptt.v34i2.3902
Rehm, J., Reshodko, I., & Gundersen, O. E. (2024). A virtual driving instructor that assesses driving performance on par with human experts. Expert Systems with Applications, 248(February), 123355. https://doi.org/10.1016/j.eswa.2024.123355
Shaaban, K., & Hamad, H. (2020). Critical gap comparison between one-, two-, and three-lane roundabouts in Qatar. Sustainability (Switzerland), 12(10), 1–14. https://doi.org/10.3390/su12104232
Shaaban, K., & Hamad, H. (2021). Impact of Police Enforcement on Critical Gap at Roundabouts. Transportation Research Procedia, 55(2019), 387–393. https://doi.org/10.1016/j.trpro.2021.07.001
Sharma, O., Sahoo, N. C., & Puhan, N. B. (2023). Kernelized convolutional transformer network based driver behavior estimation for conflict resolution at unsignalized roundabout. ISA Transactions, 133, 13–28. https://doi.org/10.1016/j.isatra.2022.07.004
Shawky, M., Alsobky, A., Al Sobky, A., & Hassan, A. (2023). Traffic safety assessment for roundabout intersections using drone photography and conflict technique. Ain Shams Engineering Journal, 14(6), 102115. https://doi.org/10.1016/j.asej.2023.102115
Shen, J., Liu, Q., Ye, Z., Jiang, W., & Ma, C. (2023). Autonomous bus services: current research status and future recommendations. Digital Transportation and Safety, 2(3), 229–240. https://doi.org/10.48130/dts-2023-0019
Singleton, P. A., & Poudel, N. (2023). Bicycling comfort at roundabouts: Effects of design and situational factors. Transportation Research Part F: Traffic Psychology and Behaviour, 94(November 2022), 227–242. https://doi.org/10.1016/j.trf.2023.02.008
Spanou, D., Kehagia, F., & Pitsiava-Latinopoulou, M. (2015). Roundabouts: Geometric Design and Road Safety - Case Study in the City of Kavala, Greece. Engineering, Environmental Science.
Suh, W., Kim, J. I., Kim, H., Ko, J., & Lee, Y. (2018). Mathematical Analysis for Roundabout Capacity. 2018.
Tarhuni, F., Mahat, R., Eltwati, A., Eldofani, M., & Albarki, A. (2024). Turbo-Roundabouts as a Tool for Enhancing Urban Efficiency and Safety: A Case Study. Journal of Advanced Research in Applied Sciences and Engineering Technology, 34(1), 279–288. https://doi.org/10.37934/araset.34.1.279288
Tiwari, G., & Mohan, D. (2016). Public Transport and Safety. Transport Planning and Traffic Safety, 285–299. https://doi.org/10.1201/b19737-21
TRB. (2000). Highway Capacity Manual. In Transportation Research Board (Issue May 2001). National Research Council.
TRB. (2010a). Highway Capacity Manual, Volume 1: Concepts. In Transportation Research Board (5th ed.). Transportation Research Board. WWW.TRB.ORG
TRB. (2010b). Highway Capacity Manual, Volume 3: Interrupted Flow. In Transportation Research Board (5th ed.). Transportation Research Board. WWW.TRB.ORG
TRB. (2010c). Highway Capcity Manual, Volume 2: Uninterrupted Flow. In Transportation Research Board (5th ed.). Transportation Research Board.
TRB. (2010d). Roundabouts: An Informational Guide Second Edition-NCHRP Report 672. National Academies of Sciences Engineering and Medicine (L. Rodegerdts, J. Bansen, C. Tiesler, J. Knudsen, & E. Myers (eds.)). The National Academies Press. https://doi.org/10.17226/22914
TRB. (2010e). Roundabouts: An Informational Guide Second Edition. In NCHRP Report 672. https://doi.org/10.17226/22914
TRB. (2016a). Highway Capacify Manual: A Guide tor Mulfimodal Mobilify Analysis. Volume 1: Concepts (6th ed.). Transportation Research Board. www.TRB.org
TRB. (2016b). Highway Capacity Manual: A Guide for Multimodal Mobility Analysis. Volume 3: Interrupted Flow (6th ed., Vol. 5, Issue 3). Transportation Research Board. www.TRB.org
TRB. (2022). Highway Capacity Manual 7th Edition: A Guide for Multimodal Mobility Analysis. Vol. 4: Applications Guide. National Academies of Sciences Engineering and Medicine. The National Academies Press. https://doi.org/10.17226/26432.
Treiber, M., & Kesting, A. (2013). Traffic flow dynamics: Data, models and simulation. In Traffic Flow Dynamics: Data, Models and Simulation. Springer Heidelberg New York Dordrecht London. https://doi.org/10.1007/978-3-642-32460-4
Trinh, L. T., Sano, K., Hatoyama, K., & De Silva, C. K. (2021). Analysis of motorcycle microscopic characteristics at roundabouts under mixed traffic condition: A case study of Vietnam. Journal of Traffic and Transportation Engineering (English Edition), 8(4), 605–619. https://doi.org/10.1016/j.jtte.2020.04.005
TRL. (2018). Roundabout Capacity: the Uk Empirical Methodology. 1–8.
Vichova, K., Heinzova, R., Dvoracek, R., & Tomastik, M. (2021). Optimization of Traffic Situation Using Roundabouts. Transportation Research Procedia, 55(2019), 1244–1250. https://doi.org/10.1016/j.trpro.2021.07.106
Vinayaraj, V. S., & Perumal, V. (2022). Safety evaluation of urban roundabouts in India : a safety performance function-based approach. 3, 1–16.
Wang, N., Wang, X., Yan, H., & He, Z. (2024). From rectangle to parallelogram: an area-weighted method to make time-space diagrams incorporate traffic waves. Digital Transportation and Safety, 3(1), 1–7. https://doi.org/10.48130/dts-0024-0001
Yannis, G., Laiou, A., Dragomanovits, A., Nikolaou, D., Michelaraki, E., Folla, K., Kallidoni, M., Georgiopoulos, S., & Parissis, M. (2023). Effective road safety measures in Greece. Transportation Research Procedia, 72(2022), 147–154. https://doi.org/10.1016/j.trpro.2023.11.388
Zakeri, S., & Choupani, A. A. (2021). Operational Evaluation of a Throughabout to Give Priority to Public Transport at Standard Roundabouts. Journal of Advanced Transportation, 2021. https://doi.org/10.1155/2021/1840040
Zehawi, N. R. (2018). A System Dynamics Simulation to Estimate Roundabout Entry Capacity by Adopting Three Different Methods. Djes, 11(4), 35–45. https://doi.org/10.24237/djes.2018.11406
Žura, M. (2022). Roundabout Capacity Estimation Model Considering Driver Behaviour on the Exiting and Entry Flows. Promet - Traffic - Traffico, 34(3), 397–405. https://doi.org/10.7307/PTT.V34I3.3973
Article Sidebar
