Laboratory experiments on the entrainment by a Concentrated Benthic Suspension

The deposition of cohesive sediments in estuarin and eoestal environments can lead to a range of managerial problems. To deal with these problems it is essential to understand the behaviour of cohesive sediment and its interaction with the flow field. During slack water, cohesive sediment is deposited and a Concentrated Benthic Suspension (CBS)...

Transport of cohesive sediments: Classification and requirements for turbulence modelling

This report describes a classification of sediment-laden flows, which gives an overview of the different transport forms of fine sediment and the interactions of the different processes as acting in an estuary. At the outs et of the proposed classification a distinction in physical states of water-sediment mixtures is made. A water-sediment...

Consolidation and strength evolution of Dollard mud: Measurement report on laboratory experiments

Many harbours in the world suffer from high siltation rates in their basins. To guarantee safe shipping, harbour authorities have to maintain the navigable depth by having dredged large amounts of mud. Some authorities relate the navigable depth to a depth at which the density is equal to a certain value, e.g. 1200 kg/m3. However, the shear...

Laboratory experiments on consolidation and strength evolution of mud layers

Many harbours in the world suffer from high siltation rates in their basins. To guarantee safe shipping, harbour authorities have to maintain the navigable depth by dredging large amounts of mud. Some authorities relate the navigable depth to the depth at which the density is equal to a certain value, e.g. 1200 kg/m3. However, the shear strength...

Consolidation and strength evolution of Caland-Beer Channel mud: Measurement report on laboratory experiments

Many harbours in the world suffer from high siltation rates in their basins. To guarantee safe shipping, harbour authorities have to maintain the navigable depth by having dredged large amounts of mud. Some authorities relate the navigable depth to a depth at which the density is equal to a certain value, e.g. 1200 kg/m3. However,the shear...

The Ems/Dollard estuary: A physical system description

In 1993 an interdisciplinary research programme on the behaviour of mud in tidal waters was initiated by the The Board of NWO-BOA. The programme aims at obtaining more detailed insight in the dominant processes that govern the transport behaviour of mud. These processes have strong time variability and therefore the general approach is to obtain...

Consolidation theory and rheology of mud: A literature survey

In the framework of project Strength evolution of soft consolidating mud layers, financially supported by the Netherlands Foundation of Technology, a literature survey on consolidation theory and rheological modelling of mud was carried out. A consolidation theory, focused on the Gibson equation (Gibson et al., 1967), is presented. The solution...

Liquefaction and erosion of mud due to waves and current: Experiments on Westwald Clay

A research project was carried out at the Delft University of Technology in order to study the interaction between waves as weil as a current and a muddy bed. For this purpose several experiments were made on two artificial clays, namely China Clay and Westwald Clay. The results of the experiments on China Clay were reported by De Wit (1994). In...

An entrainment model for fluid mud

An entrainment model for fluid mud is derived by integrating the equation for turbulent kinetic energy across the mixed layer and introducing some modelling assumptions. The resulting entrainment model is similar to models of mixed-layer deepening in lakes and reservoirs, but in addition accounts for the work needed to entrain bed material. Two...

Hindered settling and consolidation of mud - analytical results

The theory of hindered settling from a suspension developed by Kynch (1952) is known to satisfactorily describe the settling and primary consolidation of mud. This theory, in which effective stresses are disregarded, is reviewed for this purpose, and some analytical results for interface formation and consolidation are obtained. In particular it...