Evaluation of Design Consistency on Horizontal Curves for Two-Lane State Roads in Terms of Vehicle Path Radius and Speed

Biljana Maljković, Dražen Cvitanić

Abstract


Experimental investigation was conducted on a 24 km long segment of the two-lane state road to collect the driver behavior data. The research involved 20 drivers driving their own cars equipped with the GPS device. Considering the impact of path radius and speed on the side friction demand, the design consistency on horizontal curves was evaluated by determining the margins of safety. The analysis showed that the vehicle path radii were mainly smaller than curve radius, on average for 12%. Regression analysis indicated that the percentage difference between the curve radius and vehicle path radius is not affected by the speed, speed differential and geometric characteristics of the curve and surrounding elements. Two different margins of safety were analyzed. One is the difference between maximum permissible side friction (based on design speed) and side friction demand, while another is the difference between side friction supply (based on operating speed) and side friction demand. Generally, demands exceeded supply side friction factors on curves with radii smaller than 150 m, whereas “poor” conditions (in terms of Lamm’s consistency levels) were noted for curves under approximately 220 m. Both values are very close to the critical radius below which higher accident rates were observed according to several accident studies. Based on the results of the research, it is proposed to use a 12% smaller curve radius for the evaluation of margin of safety and that curves with radii smaller than 200 m should be avoided on two-lane state roads outside the built-up area.


Keywords:

critical vehicle path radius; demand side friction factor; design consistency; global positioning system (GPS); horizontal curve; operating speed.

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References


Cafiso, S.; La Cava, G. 2009. Driving Performance, Alignment Consistency, and Road Safety Real-World Experiment, Transportation Research Record 2102: 1–8. http://dx.doi.org/10.3141/2102-01

Carlson, P. J.; Burris, M.; Black, K.; Rose, E. R. 2005. Comparison of Radius-Estimating Techniques for Horizontal Curves, Transportation Research Record 1918: 76–83. http://dx.doi.org/10.3141/1918-10

Castro, M.; Pardillo-Mayora, J. M.; Jurado, R. 2013. Development of a Local Operating Speed Model for Consistency Analysis Integrating Laser, GPS and GIS for Measuring Vehicles Speed, The Baltic Journal of Road and Bridge Engineering 8(4): 281–288. http://dx.doi.org/10.3846/bjrbe.2013.36

ERA-NET ROAD 2012. Safety at the Heart of Road Design. Final Report of the ERA-NET programme.

Glennon, J. C.; Weaver, G. D. 1972. Highway Curve Design for Safe Vehicle Operations, Highway Research Record 390: 15–26.

Hassan, Y.; Sayed, T.; Tabernero, V. 2001. Establishing Practical Approach for Design Consistency Evaluation, Journal of Transportation Engineering 127(4): 295–302. http://dx.doi.org/10.1061/(ASCE)0733-947X(2001)127:4(295)

Kobryń, A. 2014. New Solutions for General Transition Curves, Journal of Surveying Engineering 140(1): 12–21. http://dx.doi.org/10.1061/(ASCE)SU.1943-5428.0000113

Krebs, H. G.; Kloeckner, J. H. 1977. Investigations of the Effect of Highway and Traffic Conditions Outside Built-Up Areas on Accident Rates, Forschung Straßenbau und Straßenverkehrstechnik [Research Road Construction and Traffic Technique] 223.

Lamm, R.; Psarianos, B.; Mailaender, T. 1999. Highway Design and Traffic Safety Engineering: Handbook. McGraw Hill. 1088 p.

Lamm, R.; Psarianos, B.; Choueiri, E. M.; Soilemezoglou, G. 1995. A Practical Safety Approach to Highway Geometric Design International Case Studies: Germany, Greece, Lebanon, and the United States, in Proc. of the International Symposium on Highway Geometric Design Practices, August 30 – September 1, 1995, Texas Transportation Institute, Boston, Massachusetts, 9: 1–9.

Lamm, R.; Choueiri, E. M.; Goyal, P. B.; Mailaender, T. 1990. Comparison of Operating Speeds on Dry and Wet Pavements of Two-Lane Rural Highways, Transportation Research Record 1280: 199–207.

Modeling Operating Speed: Synthesis Report. 2011. Transportation Research Board. 136 p.

Nicholson, A. 1998. Superelevation, Side Friction, and Roadway Consistency, Journal of Transportation Engineering 124(5): 411–418. http://dx.doi.org/10.1061/(ASCE)0733-947X(1998)124:5(411)

Pérez-Zuriaga, A. M.; Camacho-Torregrosa, F. J.; García, A. 2013. Tangent-to-Curve Transition on Two-Lane Rural Roads Based on Continuous Speed Profiles, Journal of Transportation Engineering 139(11): 1048–1057. http://dx.doi.org/10.1061/(ASCE)TE.1943-5436.0000583

PIARC Technical Committee on Road Safety 2003. Road Safety Manual. World Road Association. 602 p.

Raff, M. S. 1953. Interstate Highway Accident Study, Highway Research Board Bulletin 74: 18–45. Traffic Accident Studies Washington D.C.

Said, D.; Halim, A. E.; Hassan, Y. 2010. Methodology for Driver Behaviour Data Collection and Analysis for Integration in Geometric Design of Highways [CD-ROM], in D. W. Harwood, A. García (Eds.). Proc. of the 4th International Symposium on Highway Geometric Design, June 1–5, 2010, Valencia, Spain.

Torbic, D. J.; Harwood, D. W.; Gilmore, D. K.; Pfefer, R.; Neuman, T. R.; Slack, K. L.; Hardy, K. K. 2004. Guidance for Implementation of the AASHTO Strategic Highway Safety Plan: A Guide for Reducing Collisions on Horizontal Curves, NCHRP Report 500 Series, Vol. 7, Transportation Research Board, Washington, D.C.

World Health Organization 2013. Global Status Report on Road Safety 2013 – Supporting a Decade of Action. Available from Internet: http://www.who.int/violence_injury_prevention/road_safety_status/2013/en/




DOI: 10.3846/bjrbe.2016.15

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doi: 10.1016/j.trpro.2020.08.160

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