Abstract：The evolution characteristics of compound fluvial channels with totally movable-bed that was made of non-uniform sediment were studied experimentally under clear water. They include the variations of stabilized width and bank erosion along the channel after the riverbed is roughened completely. Before the experiments, the compaction of sand was finished by slowly flowing water. After the whole self-formed channel was submerged for some time, the water was discharged slowly; then, the movable-bed channel was restored. The original and eroded bed surface levels were probed by using a total station and the discharge and water levels were measured by a triangular weir and automatic water level meter, respectively. The results show that with increasing deposition of sediment, the flow depth in the main channel becomes shallow, leading to the force under which sediment particles start to move is decreased. When the channel becomes stabilized, the channel width varies along the channel. After the riverbed is roughened totally, the width of the main channel is increased and the retreat rate of river bank becomes small along the channel. Under the action of clear water, the floodplain and bank of the main channel are eroded and the eroded area decreases along the channel. This is consistent with decrease in the cross-section averaged velocity along the channel.
杨克君, 聂锐华, 刘兴年. 清水作用下全动床复式河槽河床演变特性[J]. 排灌机械工程学报, 2013, 31(11): 954-957.
Yang Kejun, Nie Ruihua, Liu Xingnian. Evolution characteristics of compound fluvial channels with totally movable-bed under clear water. Journal of Drainage and Irrigation Machinery Engin, 2013, 31(11): 954-957.
[1]Sellin R H J. A laboratory investigation into the interaction between the flow in the channel of a river and that over its flood plain[J]. La Houille Blanche, 1964(7):793-802.[2]Knight D W, Demetriov J D. Flood plain and main channel flow interaction[J]. Journal of Hydraulic Engineering, 1983,109(8):1073-1092.[3]Shiono K, Knight D W. Turbulent open-channel flows with variable depth across the channel[J]. Journal of Fluid Mechanics, 1991, 222: 617-646.[4]Knight D W, Shiono K. River Channel and Food Plain Hydraulics[M]//Anderson M G, Walling D E, Bates P D. Floodplain processes: Chapter 5. Hoboken, NJ: Wiley, 1996:139-181.[5]Zarrati A R, Jin Y C, Karimpour S. Semianalytical model for shear stress distribution in simple and compound open channels[J]. Journal of Hydraulic Engineering, ASCE, 2008, 134(2): 205-215.[6]Zeng Y H, Guymer I, Spence K J, et al. Application of analytical solutions in trapezoidal compound channel flow[J]. River Research and Applications, 2012, 28(1): 53-61.[7]Liao Huasheng, Knight D W. Analytic stage-discharge formulas for flow in straight prismatic channels[J]. Journal of Hydraulic Engineering, 2007, 133(10): 1111-1122.[8]Khatua K K, Patra K C, Mohanty P K. Stage-discharge prediction for straight and smooth compound channels with wide floodplains[J]. Journal of Hydraulic Engineering, 2011,138(1):93-99.[9]Yang Zhonghua, Gao Wei, Huai Wenxin. Estimation of discharge in compound channels based on energy concept[J]. Journal of Hydraulic Research, 2012,50(1):105-113.[10]Al-Khatib I A, Dweik A A, Gogus M. Evaluation of separate channel methods for discharge computation in asymmetric compound channels[J]. Flow Measurement and Instrumentation, 2012,24:19-25.[11]Azamathulla H M, Zahiri A. Flow discharge prediction in compound channels using linear genetic programming[J]. Journal of Hydrology, 2012,454/455:203-207.[12]Costabile P, Macchione F. Analysis of one-dimensional modelling for flood routing in compound channels[J]. Water Resources Management, 2012,26(5):1065-1087.[13]Hu Chunhong, Ji Zuwen, Guo Qingchao. Flow movement and sediment transport in compound channels[J]. Journal of Hydraulic Research, 2010,48(1 EXTRA ISSUE):23-32.[14]Knight D W, Brown F A. Resistance studies of overbank flow in rivers with sediment using the flood channel facility[J]. Journal of Hydraulic Research/De Recherches Hydrauliques, 2001,39(3):283-301.[15]Lyness J F, Myers W R C, Cassells J B C, et al. The influence of planform on flow resistance in mobile bed compound channels[J]. Proceedings of the Institution of Civil Engineers: Water, Maritime and Energy, 2001,148(11):5-14.[16]Knight D W. Flow mechanisms and sediment transport in compound channels[J]. International Journal of Se-diment Research, 1999,14(2):217-236.[17]Myers W R C, Lyness J F, Cassells J. Influence of boundary roughness on velocity and discharge in compound river channels[J]. Journal of Hydraulic Research/De Recherches Hydrauliques, 2001,39(3):311-319.[18]Wormleaton P R, Sellin R H J, Bryant T, et al. Flow structures in a two-stage channel with a mobile bed[J]. Journal of Hydraulic Research, 2004,42(2):145-162.[19]Wormleaton P R, Sellin R H J, Bryant T. Conveyance in a two-stage meandering channel with a mobile bed[J]. Journal of Hydraulic Research, 2004,42(5):492-505.[20]Karamisheva R D, Lyness J F, Myers W R C, et al. Overbank flow depth prediction in alluvial compound channels[J]. Proceedings of the Institution of Civil Engineers: Water Management, 2006,159(3):195-205. [21]Knight D W, Brown F, Valentine E, et al. The response of straight mobile bed channels to inbank and overbank flows[J]. Proceedings of the Institution of Civil Engineers: Water, Maritime and Energy, 1999,136(4):211-224.[22]Tang Xiaonan, Knight D W. Migration rate of bed forms in a compound channel with overbank flow[C]//Proceedings of the 2nd IAHR Symposium on River, Coastal and Estuarine Morphodynamics, 2001:545-553.[23]Tang Xiaonan, Knight D W. Sediment transport in river models with overbank flows[J]. Journal of Hydraulic Engineering, 2006,132(1):77-86.[24]Knight D W. Flow and sediment transport in two-stage channels[C]//Proceedings of the 2nd IAHR Symposium on River, Coastal and Estuarine Morphodynamics, 2001:1-20.[25]Knight D W. Sediment transport in rivers with overbank flow[J]. Journal of Sichuan University: Engineering Science Edition, 2005,37(S):16-29.[26]Atabay S, Knight D W, Seckin G. Effects of overbank flow on fluvial sediment transport rates[J]. Proceedings of the Institution of Civil Engineers: Water Management, 2005,158(1):25-34.[27]Atabay S, Knight D W. 1-D modelling of conveyance, boundary shear and sediment transport in overbank flow[J]. Journal of Hydraulic Research, 2006,44(6):739-754.[28]Ackers P. Flow formulae for straight two-stage channels[J]. Journal of Hydraulic Research, 1993,31(4):509-531.[29]Karamisheva R D, Lyness J F, Myers W R C, et al. Improving sediment discharge prediction for overbank flows[J]. Proceedings of the Institution of Civil Engineers: Water Management, 2005,158(1):17-24.[30]Karamisheva R D, Lyness J F, Myers W R C, et al. Sediment transport formulae for compound channel flows[J]. Proceedings of the Institution of Civil Engineers: Water Management, 2006,159(3):183-193.[31]Shiono K, Chan T L, Spooner J, et al. The effect of floodplain roughness on flow structures, bedforms and sediment transport rates in meandering channels with overbank flows: Part I[J]. Journal of Hydraulic Research, 2009,47(1):5-19.[32]Shiono K, Chan T L, Spooner J, et al. The effect of floodplain roughness on flow structures, bedforms and sediment transport rates in meandering channels with overbank flows: Part II[J]. Journal of Hydraulic Research, 2009,47(1):20-28.
