Qinqin Liu , Xiaojian Liu , Jian Chen , Peng Hou , Yong He , Qisong Wang , Xiaowei Zhu , Qiang Wang , Huan Gao
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引用次数: 0
Abstract
Flocculation-settling of cohesive fine sediment is the main cause of sediment deposition and changes in topography and geomorphology in estuaries. However, studies on estuary morphology have often focused on a single influencing factor, and sediment deposition characteristics under disturbances in sediment concentration, moisture content, and external forces have rarely been considered simultaneously. The authors propose an ultrasound-assisted flocculation-settling method to analyze the various factor affecting cohesive sediment. The current study examined the sedimentation patterns of cohesive sediment with a sediment content concentration of 30%–80% through ultrasound experiments. The results show that when the sediment concentration is 40%–50%, the best effect on flocculation and sedimentation is induced by ultrasound waves. The corresponding settling height at the clear-muddy water interface is 3.05–3.45 cm, and the settling rate is 0.161–0.173 cm/min. Finally, using ultrasound waves, a moisture content of the sediment concentration of 30%–80% was analyzed based on wet and dry conditions. Taking a sediment concentration of 50% as an example, the maximum values of the variation in the water contents of the upper, middle, and lower layers of the wet basis were 0.82%, 0.51%, and 0.37%, respectively, whereas those of the upper, middle, and lower layers of the dry basis were 4.77%, 1.07%, and 0.60%, respectively. Thus, the moisture content of dry and wet sediment varied as follows: Wupper > Wmiddle > Wlower. The current research results can provide a theoretical basis and technical reference for siltation in channels, harbors, and reservoirs; the evolution of submarine deltas and coastal beaches; transportation of fluid mud; and the treatment of hyper-concentrated sediment flows.
期刊介绍:
International Journal of Sediment Research, the Official Journal of The International Research and Training Center on Erosion and Sedimentation and The World Association for Sedimentation and Erosion Research, publishes scientific and technical papers on all aspects of erosion and sedimentation interpreted in its widest sense.
The subject matter is to include not only the mechanics of sediment transport and fluvial processes, but also what is related to geography, geomorphology, soil erosion, watershed management, sedimentology, environmental and ecological impacts of sedimentation, social and economical effects of sedimentation and its assessment, etc. Special attention is paid to engineering problems related to sedimentation and erosion.