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    Vertical drains

    Vertical or Wick Drains

    Prefabricated vertical drains (PVDs) or Wick drains are applied in areas where loose, compressible, water-saturated soils make the soil unstable Soil stablisation Soil stabilisation using prefabricated vertical drains (PVDs) or Wick drains are...
    Underwater Placement in Bulk of Fill Material

    Underwater Placement in Bulk of Fill Material

    Underwater placement of fill is usually performed by trailing suction hopper dredgers and barges by opening their bottom doors or by split hull vessels Release of the material Upon arrival at the reclamation site, this vessels drop their loads...
    Subsea Rock Installation

    Subsea Rock Installation

    Subsea rock installation is a technique used for rock placement to protect marine infrastructure, especially for offshore oil, gas and wind energy projects Two types of subsea rock installation can be distinguished: One is for shallow water...
    Soil Improvement

    Soil Improvement

    Soil improvement is applied to both consolidate existing loose subsoils and sometimes specifically for compaction of newly reclaimed soil Aims of soil improvement Soil improvement is typically implemented to: prevent excessive settlement of...
    Hydraulic Fill

    Hydraulic Fill

    Hydraulic fill is material that is dredged from a borrow area or other area and placed at a site to raise the level of the land or build new land Hydraulic fill can be won from designated borrow areas or from riverbeds, seabeds or oceans The...
    Land Reclamation

    Land Reclamation

    Land reclamation is the process of creating new land by raising the elevation of a waterbed or low-lying land or by pumping water out of muddy morass areas Land reclamation can be achieved by poldering or by raising the elevation of a seabed or...
    Rainbowing

    Rainbowing

    Rainbowing is a method by which trailing suction hopper dredgers place material in shallow areas by pumping into the air through a hose with a nozzle During rainbowing, a trailing suction hopper dredger pumps the sand that has been claimed from...
    Ground Improvement

    Ground Improvement

    Ground improvement techniques are used when the behaviour of the fill mass and/or the underlying soil does not meet required design criteria Ground improvement of hydraulic fill can include: treatment of the fill mass itself, treatment of...

    Rock Fill

    Rock is often encountered during capital dredging projects and this dredged rock can become high quality fill when used within specific guidelines Rock Fill When using rock as fill in a reclamation area the following should be considered: ...

    Explosive Compaction

    Explosive Compaction (EC) involves placing a charge at depth in a borehole in loose soil and then detonating the charge It is generally used in sands to silty sands or sands and gravels Several charges are fired at one time, with delays between...
    Dynamic compaction

    Dynamic Compaction Techniques

    Dynamic compaction is a technique used for in-situ densification of granular soil deposits by heavy impact This technique primarily involves dropping a heavy weight repeatedly on the ground surface at a regular grid of impact points Compaction of...
    Vibratory surface compaction

    Vibratory Surface Compaction

    Vibratory surface compaction is a method used on the surface of a reclamation area to increase the density, shear strength, and stiffness of the fill This compaction method is undertaken at the surface of the site using vibratory rollers, plates...
    Compaction

    Compaction

    Compaction is used to increase the density of fill and improve properties such as compressibility, shear resistance and resistance against liquefaction Compaction Compaction is typically expressed in terms of relative density and effective stress...
    Dredging Techniques

    Techniques

    Dredging techniques cover a wide range of activities and for each project an analysis must be made to determine which technique is appropriate and feasible The techniques that the dredging industry have developed to execute projects are specific...