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天然河流的泥沙输移大多在浑水条件下进行,浑水条件与清水条件下的输沙机理存在一定差异。基于近底泥沙交换三状态随机-力学模式,考虑了床沙与推移质向悬移质的净交换,引入扬动概率,建立了浑水中非均匀推移质分级输沙率公式,进而导出总输沙率及推移质级配的计算式。浑水条件下进行的推移质输移水槽试验和野外实测资料验证了该理论公式的合理性与可靠性,并发现浑水条件下推移质级配可能粗于原始床沙级配。研究结果表明:在浑水中,以悬移质形式存在的砂质泥沙含量对有效估算推移质输沙率有着不容忽视的影响。在某粒级运动泥沙总量不变的前提下,由于一部分沙粒悬浮于水体中,将使得推移质数量相对减少。
Most of the sediment transport in natural rivers is under muddy water conditions, and there are some differences in the mechanism of sand transportation between muddy water and clean water. Based on the three-state stochastic-mechanical model of near-end sediment exchange, the net exchange of bed-sediment with plutonic mass was considered, and the raising probability was introduced to establish the formula of non-uniform pumped-bed grading sediment transport rate in muddy water. Sediment transport rate and the quality of the formula. Muddy water under the condition of the transfer of the transfer tank test and field data to verify the rationality of the theoretical formula and reliability, and found that the muddy water under the conditions of quality and quantity may be thicker than the original bed sand grading. The results show that the content of sandy sediment present in suspended sediment in muddy water can not be neglected to effectively estimate the sediment transport rate. Under the premise that the total amount of sand and sediment in a grain-level movement will not change, part of the sand particles will be suspended in the water body, which will result in the relative decrease of the mass of the pusher mass.