Losses of fill can occur for several reasons and can result in not meeting the quantity of fill required for the dredging operation.
When assessing the quantity of dredged material needed for a reclamation site, the amount of material potentially lost must be considered.
How material is lost
Material can be lost if the dredger is not able to extract all the material and leaves behind a certain volume of spill. These losses may occur because of:
- the currents in the borrow area;
- the overflow from the trailing suction dredgers or barges; or
- discharge through the weir boxes.
If too much material is lost, the balance between the fill required and the quantity available will be adversely affected and remedies must be considered.
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Can a preliminary model describe CSD spillage due to centrifugal advection?
Depending on its size and installed power, a Cutter Suction Dredger is capable of cutting a wide range of soil types. Although precise and relatively efficient, a CSD can spill significantly. The authors propose a preliminary model which describes spillage due to centrifugal advection.
An Analytical Approach to the Sedimentation Process in Trailing Suction Hopper Dredgers
A number of theories are used (Camp, Groot, Miedema and Vlasblom, Yagi, Braaksma, Ooijens and van Rhee) to determine the overflow losses when loading trailing suction hopper dredgers. The model derived here has several important improvements, including the speed of doing the calculations.
A Computationally Efficient Model for Predicting Overflow Mixture Density in a Hopper Dredger
Creating accurate models for the prediction of overflow losses by trailing suction hopper dredgers is an invaluable tool in determining the feasibility of land reclamation.
Modelling the Sedimentation Process in a Trailing Suction Hopper Dredger
For production, sand quality and environmental reasons predicting the amount of the so-called overflow losses when using a trailing suction hopper dredger is very important.
Adding Dynamics to the Camp Model for the Calculation of Overflow Losses
An IADC "Most Promising Student" Award has been presented to a graduate of TU Delft for his thesis which describes the dynamics of hopper loading both in simulation and as compared with actual measurements onboard a TSHD.
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Facts About
Initiating Hydraulic Fill Projects
“Facts About Initiating Hydraulic Fill Projects” describes the technical knowledge needed to design and successfully construct a land reclamation project.
Publications
Hydraulic Fill Manual
This manual, a first of its kind, is an ideal reference for all involved in the development of such infrastructure projects.