Effect of Shoulder on Safety of Highways in Horizontal Curves Using Vehicle Dynamic Modeling Considering Yaw Rate

Document Type : Research Article

Authors

1 Department of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran

2 Civil Engineering Department, Imam Khomeini International University, Qazvin, Iran.

3 Civil Engineering Department, Imam Khomeini International University, Qazvin, Iran

4 Expert engineer, Ministry of Energy, Tehran, Iran.

5 Technical and Soil Mechanics Lab. Co., Ministry of Roads and Urban Development, Tehran, Iran.

Abstract

Skidding in horizontal curves is a common type of accident that endangers passenger safety and may happen due to various reasons. Investigating the co-relations between Vehicle dynamic parameters and road shoulder type by taking yaw rate changes, the human factor (speed and encroachment angle), and road geometry (width, material, and slope of shoulder and roadway) via vehicle dynamic simulation helps to realize the skidding mechanism on horizontal curves caused by the shoulders. The importance of this study reveals by considering that similar studies have not probed the relations between vehicle dynamic and shoulder parameters based on observing the danger of skidding. The simulation process in this study is conducted via the vehicle dynamic simulation software Carsim and Trucksim which can evaluate the stability of the vehicle in various driving conditions. By conducting 324 scenarios generated by the simulation software, several models are achieved based on the relation between parameters affecting vehicle yaw rate for Sedan, SUV, and Truck types of vehicles. Scenarios are generated by considering unwanted road departures in horizontal curves in all types of vehicles with various speeds and placements of outer tires on different types of shoulders. As the results of the simulated scenarios demonstrate, the average yaw rate of a Truck is 6.41 to 19.65 percent higher than the SUV and Sedan types, respectively. Even though the average amount of yaw rate for Sedan against SUV and Truck is greater by 6.7% and 20%, respectively. Also, the simulation results show that when the outer tires are on a gravel shoulder and the inner ones are on the roadway in horizontal curves, the amount of yaw rate for Sedan, SUV, and Truck would be 1.06, 0.76, and 0.66 percent, respectively, which are lower than the cases in which the gravel shoulder is replaced with an asphalt one. Furthermore, Results indicate that shoulders with various widths, cross slopes, and materials, influence aspects of highway safety-related to vehicle yaw rate significantly. This influence depends on the dynamic and geometric features of each type of vehicle.

Keywords

Main Subjects

References

  1. G. Karlaftis, A.P. Tarko, Heterogeneity considerations in accident modeling, Accident Analysis & Prevention, 30(4) (1998) 425-433.
  2. AASHTO, Policy on geometric design of highways and streets, American Association of State Highway and Transportation Officials, Washington, DC, 1(990) (2001) 158.
  3. Vaa, T. Assum, R. Elvik, Driver support systems: Estimating road safety effects at varying levels of implementation, TØI Report, (1202/2012) (2012).
  4. A. Kordani, B.T. Kallebasti, A. Attari, Effect of Shoulder Width and Drop-off on Vehicle Rollover and Shoulder Crossover Using Vehicle Dynamics Simulations.
  5. Gross, Jovanis, P. P., Eccles, K. A., & Chen, K. Y, Safety evaluation of lane and shoulder width combinations on rural, two-lane, undivided roads, 2009.
  6. Lv, N. Chen, P. Li, Multi-objective H∞ optimal control for four-wheel steering vehicle based on yaw rate tracking, Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 218(10) (2004) 1117-1123.
  7. Piyabongkarn, J. Grogg, Q. Yuan, J. Lew, R. Rajamani, Dynamic modeling of torque-biasing devices for vehicle yaw control, 0148-7191, SAE Technical Paper, 2006.
  8. Du, N. Zhang, F. Naghdy, Velocity-dependent robust control for improving vehicle lateral dynamics, Transportation research part C: emerging technologies, 19(3) (2011) 454-468.
  9. Chen, T.U. Saeed, M. Alinizzi, S. Lavrenz, S. Labi, Safety sensitivity to roadway characteristics: A comparison across highway classes, Accident Analysis & Prevention, 123 (2019) 39-50.
  10. Moomen, M. Rezapour, M.N. Raja, K. Ksaibati, Predicting injury severity and crash frequency: Insights into the impacts of geometric variables on downgrade crashes in Wyoming, Journal of traffic and transportation engineering (English edition), 7(3) (2020) 375-383.
  11. Brown, S. Brennan, on the required complexity of vehicle dynamic models for use in simulation-based highway design, Journal of safety research, 49 (2014) 105. 101-112.
  12. Qu, Y. He, X. Sun, J. Tian, Modeling of lateral stability of tractor-semitrailer on combined alignments of freeway, Discrete Dynamics in Nature and Society, 2018 (2018).
  13. FHWA-HRT-09-031, Roadside safety analysis program (RSAP)—engineer’s manual, National Cooperative Highway Research Program (NCHRP) Report 492, National Research Council. Transportation Research Board, Roadside safety analysis program (RSAP)—engineer’s manual, National Cooperative Highway Research Program (NCHRP) Report 492, 2003.
  14. AASHTO (Road side Design guide) American Association of State Highway and Transportation Officials, 4th ed., Washington, DC, 2011.
  15. J. Torbic, O’Laughlin, M. K., Harwood, D. W., Bauer, K. M., Bokenkroger, C. D., Lucas, L. M., and Varunjikar, T, NCHRP report 774 Superelevation criteria for sharp horizontal curves on steep grades., Transportation Research Board of the National Academies, Washington, DC, 2014.
  16. Ghandour, A. Victorino, M. Doumiati, A. Charara, Tire/road friction coefficient estimation applied to road safety, in: 18th Mediterranean Conference on Control and Automation, MED'10, IEEE, 2010, pp. 1485-1490.
  17. Melzi, E. Sabbioni, on the vehicle sideslip angle estimation through neural networks: Numerical and experimental results, Mechanical Systems and Signal Processing, 25(6) (2011) 2005-2019.
  18. Rajmani, Vehicle dynamic and control, in, Springer, 2006.
  19. A. Kordani, S. Javadi, A. Fallah, The effect of shoulder on safety of highways in horizontal curves: with focus on roll angle, KSCE Journal of Civil Engineering, 22(8) (2018) 3153-3161.
AUT Journal of Civil Engineering
Volume 5, Issue 3
September 2021
Pages 449-464

Files

Share

How to cite

Statistics