含沙浑水体的黏度测量及应用分析

Measurement and Application Analysis of Viscosity of Turbid Water

含沙浑水体的高速冲击会对海底构筑物造成破坏,在计算浑水体对构筑物的作用力时,黏度是一项重要参数。本文利用落球试验和流变仪测试试验,测定了不同浓度含沙浑水体的黏度,给出其起始黏度与动力作用后的稳定黏度。结果表明:含沙量在大于400g/L时,浑水体为可用赫巴模型描述的非牛顿流体,并可简化为宾汉体;在含沙量小于400g/L时,浑水体仍可用宾汉体模型描述,在忽略较小的初始剪切应力时,可简化为牛顿流体。浓度大于400g/L的浑水体的起始黏度约为稳定黏度的100倍。文中讨论了含沙浑水体起始黏度与稳定黏度在工程计算应用中的适用情况。

Turbid water will cause damage to the seafloor structure. Viscosity is an important parameter in calculating the force of turbid water on the structure. As the turbid water has a certain rheological properties, the viscosity has the difference between the initial station and the stability station after dynamic action. In this paper, use falling ball test and rheometer test to determine the different concentrations of turbid water viscosity, given the initial viscosity and stable viscosity. In this paper, the turbid water is non-Newton fluid and can be described by the Bingham model with the sediment concentration greater than 400 g/L, and can be simplified as Bingham; when the sediment concentration is less than 400 g/L, turbid water is still available as Bingham model ignoring the small initial shear stress, can be simplified as Newton fluid. The initial viscosity of a muddy water body with a concentration greater than 400g/L is about 100 times that of the stable viscosity, the application of initial viscosity and steady viscosity of turbid water in engineering calculation and application are discussed.