Author(s): Yuan Lin; Huaitao Qin; Jin Guo; Jiawang Chen
Linked Author(s):
Keywords: Clay sediment; Rheology; Particle interaction
Abstract: Clay sediments are the main component of the seabed sediment. The interactions between the nano-sized, disk-shaped and charged clay particles are complicated, which controls the flowing and the transportation criteria of the sediment. The rheological behavior of the clay sediment modeled by laponite-water (LW) mixtures is studied experimentally by a rotational rheometer. The yield stress of the LW system decreases with increasing water content. Meanwhile, the yield stress first increases and then decrease with increasing salinity. It is considered that the face-face repulsive electrostatic interaction between clay platelets dominates the yield behavior. A yield stress model is developed to describe the change of the yield stress with both the water content and the salinity. When the LW system starts to flow, the viscosity decreases with increasing shear. A master curve of viscosity is composed from the viscosity-stress curves at different water contents if the applied shear stress is normalized by the yield stress and the viscosity normalized by a characteristic viscosity. This study is to provide the basal understanding of the clay sediment rheology and its mechanism for the subsequent investigation on the transportation of the sediment systems with strong interparticle interaction.
Year: 2020