Rheological and structural analysis of mud from Port of Hamburg, Germany

Abstract:

In this study, mud samples were collected from different locations in the Port of Hamburg, Germany. A rheological analysis of the samples was performed with amplitude sweep, frequency sweep, stress ramp-up and structural recovery tests. The changes in structural arrangement upon shearing of mud samples was examined by using modified form of RheOptiCAD. In the final part, the detailed analysis of mud flocs was performed with the help of floc-camera settling setup, in order to obtain the floc size, floc density and settling velocity of flocs.

The results showed that the samples containing higher amount of organic matter (i.e., P1 and P2) displayed higher values of rheological properties. The RheOptiCAD analysis confirmed the formation of cylinder-like structures in mud sediments upon shearing action, which explains the second plateau (i.e., two-step yielding). The floc size and floc settling velocity behaviours are aligned with the organic matter content, i.e., P1 > P2> P3 > P4.