Evaluation of the optimal geometry of the hump slab in desert railways with the solid-gas two-phase simulation approach
Document Type : Original Article
Authors
1 Assistant Professor, Road, Housing and Urban Development Research Center, Tehran, Iran.
2 M.Sc., Student, Department of Civil & Environmental Engineering, Amirkabir University of Technology, Tehran, Iran.
3 استاد، دانشکده مهندسی عمران و محیط زیست، دانشگاه صنعتی امیرکبیر، تهران، ایران
10.22034/road.2023.371313.2115
Abstract
One of the inevitable necessities for the development of the rail transport network is to pass through desert and sandy areas. At the same time, desert railways increase maintenance and repair costs, reduce speed and block the line during operation, and even cause the train to derail. So far, various solutions have been proposed to deal with quicksand in desert railways. One of the newly developed methods is the hump slab track, which seeks to control and pass the amount of incoming sand from the railway track. In this system, the ballast material is removed and the height of rails is raised by means of concrete supports known as humps. As a result, channels for the passage of sands under the rails are created. The geometry of the hump should be such that, in addition to favorable aerodynamic conditions, it provides maximum free space for sand to pass through. In this research, with the aim of optimizing the geometry of the hump, different sections for the hump have been investigated and then two main sections including oval and rectangle-semicircle with two different heights have been evaluated. Simulations have been carried out in the platform of computational fluid dynamics and in Ansys Fluent software. Two-phase solid-gas flow including a sand flood and wind flow has been passed through the models and the amount of sand volume fraction has been compared. The results show that the rectangular-semi-circular geometric section (height of 20 cm) shows more favorable results against the influx of quicksand.
Keywords
-امرالهی، ع.، (1400)، "گزارش مناطق ماسه گیر خطوط راه آهن ج.ا.ا، اداره کل خط و سازههای فنی راه آهن".
- فتحعلی، م.، (1387)، "ارایه روسازی دال خط کوهاندار برای رفع معضل راه آهنهای مناطق کویری"، پایان نامه کارشناسی ارشد، دانشکده مهندسی راه آهن، دانشگاه علم و صنعت ایران.
-Bruno, L., Horvat, M., & Raffaele, L., (2018), “Windblown sand along railway infrastructures: A review of challenges and mitigation measures”, Journal of Wind Engineering and Industrial Aerodynamics, Vol. 177, pp. 340-365.
-Horvat, M., Bruno, L., & Khris, S., (2022), “Receiver Sand Mitigation Measures along railways: CWE-based conceptual design and preliminary performance assessment”, Journal of Wind Engineering and Industrial Aerodynamics, Vol. 228,
pp. 105109.
pp. 105109.
-Li, G. S., Qu, J. J., Li, X. Z., & Wang, W. F., (2014), “The sand-deposition impact of artificial gravel beds on the protection of the Mogao Grottoes”, Scientific reports, Vol. 4, No. 1, pp. 1-8.
-Malkaneh, M. and Talaee, M. R., (2019), “Numerical Study of the Humped Slab Track Behavior in SandStorm by Modeling Two-Phase Flow”, Journal of Transportation Infrastructure Engineering, Vol. 5, No. 1,
pp. 37-56.
pp. 37-56.
-pandrol, (2022), “Fastclip FCA Product Guide”, [online] Available at: https://www.pandrol.com/wp-content/uploads/2021/01/FCA-Product-Guide-EN.pdf.
-Raffaele, L., & Bruno, L., (2020), “Windblown sand mitigation along railway megaprojects: A comparative study, Structural Engineering International, Vol. 30, No. 3, pp. 355-364.
-Rahdari, M. R., Gyasi-Agyei, Y., & Rodrigo-Comino, J., (2021), “Sand drifts potential impacts within desert railway corridors: a case study of the Sarakhs-Mashhad railway line”, Arabian Journal of Geosciences, Vol. 14, No. 9, pp. 1-14.
-Zakeri, J. A. and Fathi, A., (2017), “Analysis the Influence of Different Forms of Geometric Humps on Sand Track Crossing the Desert Using the Fluent Simulation Software”, Journal of Transportation Research, Vol. 14, No. 2, pp. 349-362.
-Zakeri, J. A., Esmaieli, M., Fathali, M., (2010), “Introducing New Humped Slab Track Superstructure for Obviating the Problems of Desert Railways”, Modares Civil Engineering journal, Vol. 10, No. 2.
-Zakeri, J. A., Esmaieli, M., Fathali, M., (2011), “Evaluation of humped slab track performance in desert railways”, Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, Vol. 225, No. 6, pp. 566-573.
-Tavili, A., (2015), “Studying and designing the construction of a biological protection belt for stabilization Flowing sands in Shurgaz area of Zahedan”.
-Vossloh, (2022), “System W. 14 – the world’s most popular solution”, [online] https://media.vossloh.com/media/01_product_finder/vfs/pf_system_w_14/Vossloh_System_W_14_EN.pdf.