Rheology of Concentrated Cohesive Sediments

The elastic and yield behavior of cohesive K-illite suspensions in 10⁻¹M KCl and at pH ≈ 4.7 is investigated using shear wave propagation and applied stress rheometry. Elastic moduli and quasi-static yield stresses show a power law dependence on volumetric solids concentration over the experimental range 0.02 ≤ φ ≤ 0.07. Cohesive energy of the network structure in these sediments calculated using an instantaneous modulus derived from creep curves shows a dramatic increase with φ.