Small-Scale Sounding Tests on Soft Saturated Cohesive Soils

Knowledgeof the yield strength of subaqueous sediment beds is essential to calculate their sensitivity to erosion and failure. Also for dredging operations yield strength is a parameter of the utmost importance. This report describes measurements of the yield strength profiles of cohesive sediment samples with a sounding instrument developed by the Hydromechanics Laboratory of this university. From the forces acting on a geometry slowly penetrating into a sediment sample the strength profile is calculated. During some experiments also pore and total pressures were measured. The influencesof penetration geometry and traversing speed are discussed. The method is shown to be suitable to measure bed strength profiles fairly accurately. Several sediment types with varying consolidation times were tested.Hydraulic EngineeringCivil Engineering and Geoscience