A new approach to optimizing the radius of the horizontal curves of the country's military roads

Document Type : Original Article

Authors

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

2 Ph.D., Civil Engineering Dept., Imam Khomeini International University, Qazvin, Iran.

3 M.Sc., Grad., Department of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran.

10.22034/tri.2021.241341.2798

Abstract

In Iran, the Code 415 is used to study the geometric design and road safety. There are no specific manuals to design military roads. This paper is aimed to optimally design the radius of horizontal curves in military roads under more realistic conditions. For the purpose of road geometric design in the Code 415, the minimum radius of horizontal curves is calculated based on the point mass model. In the real world, vehicles move like a multi-dimentional mass not a rigid one, therefore the equation presented in the code 415 can be questioned. This doubt seems to be reasonable, since in reality, the forces acted on each single tire differes as vehicle passes the horizontal curve. So, in order to analyze more accurately, 112 scenarios are considered in this research. The scenarios include different slopes, grades, rollover indices, load transfer indices, lateral friction factors in the horizontal curves. The results showed that considering the dynamic limitations of lateral acceleration, Rollover index, load transfer index, Roll rate, lateral friction factor, the proposed radius in this paper can be lower than the proposed radius in 415 by 95.6 percent. These proposed radii of of horizontal curves are suitable and widely used in difficult operational-military routes.

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References

-عطاری، ع.، (1393)، "بررسی اثر شیب شیروانی در ارتقا ایمنی وسایل نقلیه خارج شده از جاده­های برون شهری با توجه به شبیه­سازی حرکت وسایل نقلیه"، پایان­نامه کارشناسی ارشد، دانشگاه آزاد اسلامی (واحد اهر).
-جابری، ا. ح.، (1395)، "آنالیز حاشیه ایمنی قوس افقی در جاده­های برونشهری بر اساس آشتو (کتاب سبز)"، پایان نامه کارشناسی ارشد، دانشگاه بین المللی امام خمینی.
-AASHTO. (2011), "A Policy on Geometric Design of Highways and Streets", AASHTO.
-Chang, T. H., (2001), "Effect of vehicles' suspension on highway horizontal curve design", Journal of transportation engineering, 127(1), pp.89-91.
-Choudhari, T., & Maji, A., (2021), "Risk assessment of horizontal curves based on lateral acceleration index: a driving simulator-based study", Transportation in developing economies, 7(1), pp.1-11.
-Easa, S. M., & Dabbour, E., (2003), "Design radius requirements for simple horizontal curves on three-dimensional alignments", Canadian Journal of Civil Engineering, 30(6), pp.1022-1033.
-Echaveguren, T., Bustos, M., & De Solminihac, H., (2004), "A method to evaluate side friction in horizontal curves, using supply-demand concepts", Paper presented at the 6th International Conference on Managing Pavements: The Lessons, The Challenges, The Way AheadQueensland Department of Main RoadsARRBFRH GroupExor CorporationPavement Management ServicesFederal Highway AdministrationWorld HighwaysGHDBrisbane City CouncilTasmania Department of Infrastructure, Energy and ResourcesAustralian Road Federation (ARF) HansenCooperative Research Centre for Construction Innovation.
 
-Figueroa Medina, A. M., & Tarko, A. P., (2007), "Speed changes in the vicinity of horizontal curves on two-lane rural roads", Journal of transportation engineering, 133(4), pp.215-222.
-Findley, D. J., Hummer, J. E., Rasdorf, W., Zegeer, C. V., & Fowler, T. J., (2012), "Modeling the impact of spatial relationships on horizontal curve safety", Accident Analysis & Prevention, 45, pp.296-304.
-Himes, S. C., (2013), "Reliability Based Design of Horizontal Curves Considering the Effects of Grades".
-Imberg, J., & Palmberg, A., (2015), "How curve geometry influences driver behavior in horizontal curves-A study of naturalistic driving data".
-Kilinc, A. S., & Baybura, T., (2012), "Determination of minimum horizontal curve radius used in the design of transportation structures", depending on the limit value of comfort criterion lateral jerk TS06G-Engineering Surveying, Machine Control and Guidance.
-Kordani, A. A., Javadi, S., & Fallah, A., (2018), "The effect of shoulder on safety of highways in horizontal curves: With focus on roll angle", KSCE Journal of Civil Engineering, 22(8), pp.3153-3161­.
-Lamm, R., & Choueiri, E. M., (1987), "Recommendations for evaluating horizontal design consistency based on investigations in the state of New York", Transportation Research Record, 1122(68), e78.
-Noland, R. B., & Oh, L., (2004), "The effect of infrastructure and demographic change on traffic-related fatalities and crashes: a case study of Illinois county-level data", Accident Analysis & Prevention, 36(4), pp.525-532.­
-Othman, S., Thomson, R., & Lannér, G., (2014), "Safety analysis of horizontal curves using real traffic data", Journal of transportation engineering, 140(4), 04014005.
-Qu, G., He, Y., Sun, X., & Tian, J., (2018), "Modeling of lateral stability of tractor-semitrailer on combined alignments of freeway", Discrete Dynamics in nature and Society.
Tan, C. H., (2005), "An investigation of comfortable lateral acceleration on horizontal curves: The Pennsylvania State University."
-Xu, J., Yang, K., Shao, Y., & Lu, G., (2015), "An experimental study on lateral acceleration of cars in different environments in Sichuan", Southwest China. Discrete Dynamics in nature and Society.
Journal of Transportation Research
Volume 19, Issue 1 - Serial Number 70
January 2022
Pages 111-128

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