【摘要】 沉速是细颗粒黏性泥沙动力特性的关键参数，对于认识细颗粒泥沙运动规律以及预测港口航道冲淤演变具有重要意义。细颗粒黏性泥沙因其粒径小，比表面积大、颗粒间容易发生絮凝，其沉速受到多重因素的影响，其中盐度和泥沙浓度对其影响较为显著。采用嘉兴港航道现场采集的原状泥沙，利用沉降桶进行了0～15‰盐度范围和1～20 kg/m~3泥沙浓度范围内不同盐度和泥沙浓度条件下共42组细颗粒泥沙静水沉速试验。试验结果表明，当盐度小于7～9‰时，随着盐度的增加，泥沙沉速逐渐变大；当盐度大于7～9‰后，随着盐度继续增加，沉速逐渐减小而后趋于稳定。而当泥沙浓度小于8～10 kg/m~3时，随着泥沙浓度增加，沉速逐渐增大；当泥沙浓度大于8～10 kg/m~3时，沉速逐渐减小。另外，相比单一因素的影响，盐度和泥沙浓度存在共同作用，其共同作用对沉速的影响更大，对比分析了不同条件下盐度和泥沙浓度对沉速的影响。拟合建立了不同盐度和泥沙浓度影响下细颗粒泥沙的静水沉速公式，并和前人的研究结果进行了验证对比，研究结果可为嘉兴港航道泥沙运动规律研究提供相应的参考。更多还原

【Abstract】 Settling velocity is a key parameter in the dynamic characteristics of fine-grained cohesive sediments,holding significant importance for understanding the movement patterns of fine sediments and predicting the evolution of scour and fill in port channels. Due to their small particle size, large specific surface area, and tendency for flocculation between particles, the settling velocity of fine-grained cohesive sediments is influenced by multiple factors, with salinity and sediment concentration exerting particularly significant effects. Using in situ sediment samples collected from the Jiaxing Port channel, 42 sets of hydrostatic settling velocity tests were conducted in a sedimentation tank. These tests covered a salinity range of 0–15 ‰ and a sediment concentration range of 1–20 kg/m~3, examining the combined effects of varying salinity and sediment concentration. The results indicate that when salinity is below 7–9‰, settling velocity increases gradually with rising salinity; beyond this range, settling velocity gradually decreased and stabilised with further salinity increases. For sediment concentrations below 8–10 kg/m~3, velocity increased with concentration; above this threshold, velocity progressively decreased. Furthermore, compared to the influence of individual factors, salinity and sediment concentration exhibit synergistic effects, with their combined impact exerting a greater influence on sedimentation velocity. A comparative analysis was conducted on the effects of salinity and sediment concentration on sedimentation velocity under varying conditions. A formula for the hydrostatic sedimentation velocity of fine-grained sediments under different salinity and sediment concentration conditions was established through fitting, and validated against previous research findings.These results may provide relevant reference for studies on sediment transport patterns within the Jiaxing Port channel.更多还原