The effect of initial concentration on the consolidation behaviour of mud: A study on lake Markermeer sediment

Land reclamations in deltaric areas provide space to meet the demand for a safe place to live and work. Sand, a traditional filling material in some locations is becoming scarcer. An alternative filling material is mud. Mud consists of clay, silt, sand, organic material, water and gas. Therefore, it is a versatile material and difficult to...

Morphodynamic optimisation study of the design of semi-permeable dams for rehabilitation of a mangrove-mud coast: A case study of the Building-with-Nature project in Demak, Indonesia

Due to the removal of mangrove forests, the coastal zone of Demak district has suffered from severe erosion. One of the proposed solutions to restore the sediment balance and encourage mangrove re-establishment, is the construction of semi-permeable dams. This study aims to optimise the design of such structures. A 2DH site-specific model was...

Consolidation be haviour of soft cohesive soils, the correlation between different scale model tests: Case study of the Marker Wadden

A group of islands will be constructed in the lake Markermeer to act as nature reserve for birds, called the Marker Wadden. These islands will be constructed out of soft clay, dredged from the bottom of the lake. Building with soft cohesive soils, also referred to as mud, is still a largely unknown territory. Traditionally, sand is used for land...

The effect of pH and the solids composition on the settling and self-weight consolidation of mud

A demand to use mud as fill material for land reclamations has emerged over the past years. Such reclamations start with pumping a muddy suspension into an area enclosed by dikes. The particles in suspension then settle to form a mud layer, so that the supernatant can be removed. This filling process may be repeated several times to completely...

Autonomous dredging of mud

There are many locations where the accumulation of mud poses a problem. In lakes it can have a negative influence on the ecological situation and in port basins it can hinder traffic. Usually these mud deposits are removed periodically with regular dredging vessels. Looking at the continuous nature of the mud deposition and at the trend of an...

Sand-mud erosion from a soil mechanical perspective

‘Wetlands’ in tidal lagoons and estuaries are among the most valuable ecosystems in the world. Managing these systems requires both a thorough knowledge and validated tools to predict their behavior and development. An important morpho-dynamic process herein is the erosion (‘pick-up’) of the bed, which are in inter-tidal areas often composed of...

Estuarine Ecosystem Engineering: Biogeomorphology in the estuarine intertidal

The aim of this thesis was to investigate how (macro)benthic organisms interact with the ecological functioning, erodibility and small- to medium-scale morphodynamics of estuarine intertidal sediment by modulating its composition and/or properties. In these interactions, scale is of great importance for the ecosystem engineers. The changes they...

Uncertainty analysis of the mud infill prediction of the Olokola LNG terminal

For a proposed liquefied natural gas export facility, Olokola LNG (OKLNG), located at the western limits of the Niger Delta in Nigeria a 10 km long and 17 m deep approach channel is designed for tankers to reach the terminal at the shoreline. Mud is expected to be deposited in the channel because of the persistent swell climate which mobilizes...

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...

Slibdichtheid: Een onderzoek naar de dichtheidsopbouw van sliblagen in de Maasmond en het Caland-Beerkanaal

Op basis van periodiek uitgevoerde lodingen en dichtheidsmetingen uit de periode 1994-1995 is in dit rapport meer kennis over het gedrag van sliblagen en de dichtheidsopbouw van deze lagen in de Maasmond en het Caland-Beerkanaal verkregen. De probleemstelling luidde als volgt : Hoe verschilt de dichtheidsopbouw van sliblagen per peiling en/of ...

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...

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...