Рhysical simulation of erosion of bottom pits
DOI:
https://doi.org/10.32347/2411-4049.2020.3.78-93Keywords:
erosion, sediment transport, sand ripples, bottom pitsAbstract
The present paper is devoted to research of the erosion of large-scale sand pits in the water flow. The investigations were performed in the hydrodynamic flume with sandy bottom. To provide suitable conditions for sediment transport in the flume, the analysis of the factors leading to the motion of sediments was carried out in accordance with the Shields diagram. It was shown that the flow regime created in the laboratory channel promotes the development of natural bed forms such as ripples. Estimations of the velocity of movement of the ripples were obtained. The experiments with large sand pits on the flume bottom demonstrated that those disturb the balance of sediments and cause the reformatting of the water flow. To assess the influence of the pit configuration on the erosion process, two-dimensional triangular and trapezoidal pits were considered. It was found that the longitudinal profile of the triangular pit changes due to sediment deposition on its upper slope and erosion of the lower slope. The pit upper slope levels out and shifts forward due to the continuous flow of sediment in this region. The depth of the unevenness also decreases owing to deposition of the sediment directly on its bottom. Due to the blow of water jet to the pit lower slope, the zone of maximum erosion of the bottom surface is observed here. The bottom reformatting leads to the displacement of the pit downstream. Studies of the erosion of the trapezoidal pit have shown that its upper slope is first shifted toward the lower slope until the trapezoidal profile turns into a triangular one. The pit erosion causes also the deformation of natural forms of the channel bed and destabilization of sediment discharge. The analysis of the obtained data demonstrated that the reformation of channel bed is a durable process depending of the ratio of pit scales to the volume of sediment. The present study is useful for development of engineering solutions directed to reduction of risks caused by the interaction of sand quarries with hydraulic structures in rivers.References
van Rijn, L. C. (1984). Sediment transport, Part I: Bed load transport. Journal of Hydraulic Engineering, 110 (10), 1431-1456.
Wiberg, P. L., & Smith, J. D. (1987). Calculation of the critical shear stress for motion of uniform and heterogeneous sediments. Water Resources Research, 23 (8), 1471-1480.
Papista, E., Dimitrakis, D., & Yiantsios, S. G. (2011). Direct numerical simulation of incipient sediment motion and hydraulic conveying. Ind. Eng. Chem. Res., 50, 630-638. https://doi.org/10.1021/ie1000828
Simões, F. J. M. (2014). Shear velocity criterion for incipient motion of sediment. Water Science and Engineering, 7(2), 183–193. https://doi.org/10.3882/j.issn.1674-370.2014.02.006
Buffington, J. M., & Montgomery, D. R. (1997). A systematic analysis of eight decades of incipient motion studies, with special reference to gravel-bedded rivers. Water resources research, 33 (8), 1993-2029.
Beheshti, A. A., & Ataie-Ashtiani, B. (2008). Analysis of threshold and incipient conditions for sediment movement. Coastal Engineering, (55), 423-430. https://doi.org/10.1016/j.coastaleng.2008.01.003
Marsh, N. A., Western, A. W., & Grayson, R. B. (2004). Comparison of methods for predicting incipient motion for sand beds. Journal of Hydraulic Engineering, 130 (7), 616-621.
Cheng, N. S. (2004). Analysis of bedload transport in laminar flows. Advances in Water Resources, 27 (9), 937-942. https://doi.org/10.1016/j.advwatres.2004.05.010
Camenen, B., & Larson, M. (2005). A general formula for non-cohesive bed load sediment transport. Estuarine, Coastal and Shelf Science, 63, 249-260. https://doi.org/10.1016/j.ecss.2004.10.019
Ouriemi, M., Aussillous, P., Medale, M., Peysson, Y., & Guazzelli, E. (2007). Determination of the critical Shields number for particle erosion in laminar flow. Physics of Fluids, 19, 061706, 1-4. https://www.doi.org/10.1063/1.2747677
Talukdar, S., Kumar, B., & Dutta, S. (2012). Predictive capability of bedload equations using flume data. J. Hydrol. Hydromech., 60, 45-56. https://doi.org/10.2478/v10098-012-0004-5
Chiew, Y.-M., & Parker, G. (1994). Incipient sediment motion on nonhorizontal slopes. Journal of Hydraulic Research, 32 (5), 649-660. https://doi.org/10.1080/00221689409498706
Dey, S., & Debnath, K. (2000). Influence of streamwise bed slope on sediment threshold under stream flow. Journal of Irrigation and Drainage Engineering, 126 (4), 255-263. https://doi.org/10.1061/(ASCE)0733-9437(2000)126:4(255)
Emadzadeh, A., Chiew, Y.-M., & Afzalimehr, H. (2010). Effect of accelerating and decelerating flows on incipient motion in sand bed streams. Advances in Water Resources, 33, 1094-1104. https://doi.org/10.1016/j.advwatres.2010.06.014
Talebbeydokhti, N., Hekmatza Deh, A. A., & Rakhshandehroo, G. R. (2006). Experimental modeling of dune bed form in a sand-bed channel. Iranian Journal of Science & Technology, 30 (B4), 503-516.
Langlois, V., & Valance, A. (2007). Initiation and evolution of current ripples on a flat sand bed under turbulent water flow. Eur. Phys. J., 22, 201-208. https://doi.org/10.1140/epje/e2007-00023-0
Tjerry, S., & Fredsøe, J. (2005). Calculation of dune morphology. Journal of Geophysical Research, 110, F04013, 1-13. https://doi.org/10.1029/2004JF000171
Sukhodolov, A.N., Fedele, J.J., & Rhoads, B.L. (2006). Structure of flow over alluvial bedforms: an experiment on linking field and laboratory methods. Earth Surface Processes and Landforms, 31, 1292-1310. https://doi.org/10.1002/esp.1330
Giri, S., & Shimizu, Y. (2006). Numerical computation of sand dune migration with free surface flow. Water Resources Research, 42, W10422, 1-19. https://doi.org/10.1029/2005WR004588
Paarlberg, A. J., Marjolein Dohmen-Janssen, C., Hulscher, S. J. M. H., & Termes, P. (2009). Modeling river dune evolution using a parameterization of flow separation. Journal of Geophysical Research, 114, F01014, 1-17. https://doi.org/10.1029/2007JF000910
Nabi, M., de Vriend, H. J., Mosselman, E., Sloff, C. J., & Shimizu, Y. (2013). Detailed simulation of morphodynamics: 3. Ripples and dunes. Water Resources Research, 49, 1-14. https://doi.org/10.1002/wrcr.20457
Grigoriadis, D. G. E., Balaras, E., & Dimas, A. A. (2009). Large-eddy simulations of unidirectional water flow over dunes. Journal of Geophysical Research, 114, F02022, 1-19. https://doi.org/10.1029/2008JF001014
Chang, K., & Constantinescu, G. (2013). Coherent structures in flow over two-dimensional dunes. Water Resources Research, 49, 2446-2460. https://doi.org/10.1002/wrcr.20239
Jensen, J. H. (2001). Sediment transport and backfilling of trenches in oscillatory flow. Journal of Waterway, Port, Coastal, and Ocean Engineering, 127 (5), 272-281. https://doi.org/10.1061/(ASCE)0733-950X(2001)127:5(272)
Horban, I.M. (2015). Numerical modeling of the evolution of large-scale inequalities on the river bottom. Prykladna hidromekhanika, 17 (89). (in Ukrainian)
Jufin, A. P. (1974). Hydromechanization. M.: Strojizdat. (in Russian)
USACE Sedimentation investigations of rivers and reservoirs. (1995). Washington, DC: U.S. Army Corps of Engineers. EM 1110-2-4000.
Chanson, H. (2004). The Hydraulics of Open Channel Flow: An Introduction. Oxford, UK: Elsevier Butterworth-Heinemann.
Allen, J. R. L. (1970). Physical processes of sedimentation. London: George Allen & Unwin Ltd.
Kleinhans, M. G. (2004). Sorting in grain flows at the lee side of dunes. Earth-Science Reviews, 65, 75-102. https://doi.org/10.1016/S0012-8252(03)00081-3
Goncharov, V.N. (1962). Dynamics of channel flows. Leningrad: Gidrometeorologicheskoe izd-vo. (in Russian)
Borovkov, V.S. (1989). Channel processes and dynamics of river flows in urban areas. Leningrad: Gidrometeoizdat. (in Russian)
Dobycha nerudnyh stroitel'nyh materialov v vodnyh ob#ektah. Uchet ruslovogo processa i rekomendacii po proektirovaniju i jekspluatacii ruslovyh kar'erov. (2012). STO 52.08.31–2012. (Standart organizacii). Sankt-Peterburg: Izd-vo «Globus». Retrieved from http://www.twirpx.com/file/890305/. (in Russian)
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2020 Iryna M. Gorban, Anna S. Korolova, Georgiy P. Sokolovsky, Pavlo Y. Romanenko, Stepan M. Srebnyuk
This work is licensed under a Creative Commons Attribution 4.0 International License.
The journal «Environmental safety and natural resources» works under Creative Commons Attribution 4.0 International (CC BY 4.0).
The licensing policy is compatible with the overwhelming majority of open access and archiving policies.
