CALCULATION OF THE DIMENSIONS OF THE LOCAL SCOUR ZONE IN EARTHEN CHANNELS DOWNSTREAM OF HYDRAULIC STRUCTURES

Abstract

This study investigates the determination of the geometric dimensions of a local scour zone developing within a cohesive soil section downstream of a hydraulic structure. The influence of the main hydraulic characteristics of the flow, including discharge, mean flow velocity, flow depth, and hydraulic slope, as well as the physical, mechanical, and granulometric properties of the soil, on the development of local scour is examined. A computational approach is proposed to assess the intensity and spatial characteristics of scour by considering the interaction between the dynamic action of the flow and the resistance of the channel bed. The principal geometric parameters of the scour zone include the maximum scour depth, longitudinal extent, transverse dimensions, and location of the maximum scour point. Relationships between the hydraulic characteristics of the flow, soil properties, and geometric parameters of the scour zone are established based on the analysis of the governing hydraulic and sediment-related parameters. The obtained results can be used to assess channel-bed deformation downstream of hydraulic structures, determine the dimensions of local scour zones, and provide a basis for designing appropriate scour protection measures. The proposed approach contributes to improving the reliability of hydraulic structures and the efficiency of engineering solutions for mitigating local bed erosion.

Keywords

References

1. Einstein H.A. The Bed - Load Function for Sediment Transportation in Open Channel Flows. Technical Bulletin No. 1026. Washington, D.C.: U.S. Department of Agriculture, 1950. – 71 p.
2. Ackers P., White W.R. Sediment Transport: New Approach and Analysis. Journal of the Hydraulics Division, ASCE. 1973, Vol. 99, No. HY11.
3. Yalin M.S. Mechanics of Sediment Transport. 2nd ed. Oxford: Pergamon Press, 1977.
4. Van Rijn L.C. Sediment Transport, Part I: Bed Load Transport. Journal of Hydraulic Engineering, 1984, Vol. 110, No. 10, pp. 1431 – 1456.
5. Van Rijn L.C. Sediment Transport, Part II: Suspended Load Transport. Journal of Hydraulic Engineering, 1984, Vol. 110, No. 11, pp. 1613 – 1641.
6. Bagnold R.A. An Approach to the Sediment Transport Problem from General Physics. U.S. Geological Survey Professional Paper 422 - I. Washington, D.C., 1966.
7. Yang C.T. Sediment Transport: Theory and Practice. New York: McGraw - Hill, 1996.
8. Eshev S.S., Isakov A.N., Safarov A.A., Yuldosheva U.T. Calculation of Local Water Behind the Lower Water Mountings. // Journal of Advanced Research in Science, Engineering and Technology Vol. 11, Issue 2, February 2024, [ISSN: 2350 - 0328] 21419 - 21425 betlar. Copyright to IJARSET . (05.00.00, No8)
9. Eshev S.S., Bobomurodov F.F., Isaqov A.N., Mamatov N.Z. Evaluation of the influence of the physical properties of bound soils on the washing process. // Universum: texnicheskie nauki. DOI:10.32743/UniTech.2022.102.9.14293, 19 - 22 pages. Centyabr, 2022 g. (02.00.00 ; No1).
10. Eshev S.S., Bobomurodov F.F., Isakov A.N., Mamatov N.Z. Evaluating the Effect of Cohesive Strength on Self - Leaching in Bonded Soils // International Journal of Advanced Research in Science, Engineering and Technology - Vol. 9, Issue 8 , August 2022 ISSN: 2350 - 0328, 19636 - 19641 pages. Copyright to IJARSET (05.00.00, No8).
11. G‘ayimnazarov I. X. UDC 532.543: 627.157: Calculation of the parameters of the base rows in a non - stationary flow //Innovatsion texnologiyalar. – 2025. – Т. 59. – No. 3. – С. 62 - 66.
12. G‘ayimnazarov, I., Eshev, S., Bazarov, O., Latipov, S., Rakhimov, A., & Guliyeva, S. (2025, July). Investigation of the initiation of sediment movement in mixed flows. In AIP Conference Proceedings (Vol. 3256, No. 1, p. 020041). AIP Publishing LLC.
13. Eshev, S. S., Gayimnazarov, I. X., Latipov, S. A., Rahmatov, M. I., & K holmamatov, I. K. (2023, March). Calculation of parameters of subsurface ridges in a steady flow of groundwater channels. In AIP Conference Proceedings (Vol. 2612, No. 1, p. 050033). AIP Publishing LLC.
14. G‘ayimnazarov, I. X. (2024). OQIZIQLAR HARAKATINING BOSHLANISHINI TAHLIL QILISH. Oriental renaissance: Innovative, educational, natural and social sciences, 4(10), 142 - 147.
15. G‘ayimnazarov Israil Xoliqovich, Mamarasulov Sobir Raxmonqulogli, and Toshmurodov Jomurod Jahongirogli. “O‘ZAN TUBI BARQARORLIGINI BAH OLASH USULLARI” Sanoatda raqamli texnologiyalar/Цифровые технологии в промышленности 4.1 (2026): 237 - 241.