WO2015020520A1

WO2015020520A1 - Installation for dredging or deepening

Info

Publication number: WO2015020520A1
Application number: PCT/NL2014/050545
Authority: WO
Inventors: Cornelis Petrus Gerardus Maria Boot
Original assignee: Cornelis Petrus Gerardus Maria Boot
Priority date: 2013-08-05
Filing date: 2014-08-04
Publication date: 2015-02-12
Also published as: EP3030724A1; EP3030724B1; NL2011268C2

Abstract

The present invention relates to an installation for dredging or deepening a bottom in or of a body of water. The installation comprises: at least one float (2); a dredger crane (8) or a suction pipe; and a screen which in use can be positioned adjacently of an operational area of the dredger crane (8) or the suction pipe or at least upstream thereof relative to a flow direction in or of the body of water, and in use prevents the dispersal of bottom material dislodged during dredging with the dredger crane (8) or suctioning with the suction pipe or deepening of the bottom. The float (2) is selectively lowerable and dimensioned to be lowered onto or into the bottom of the body of water, and in lowered position forms the screen.

Description

INSTALLATION FOR DREDGING OR DEEPENING

The present invention relates to an installation for dredging or deepening a bottom in or of a body of water.

Such installations arc generally known in diverse embodiments. A self-propelling barge can for instance be applied with a loading well and also a dredger crane or suction pipe on the barge for the purpose of dredging and/or suctioning out and/or deepening the body of water. The dredger crane or suction pipe is employed here to scoop bottom material from dredging or deepening into the loading well. In another known embodiment of an installation a dredger crane can be arranged on a boat, barge or float separately of another vessel with a loading well, so that another such vessel can travel to and fro between the boat, barge or float where the dredging operations take place and a location for unloading bottom material from dredging or deepening. In yet another embodiment use is made of a screw or blade to dislodge bottom material in combination with a suction pipe in order to discharge dislodged bottom material to a processing location, optionally via a vessel with loading well.

All these and other known installations have collective drawbacks in respect of dislodged bottom material which is not immediately scooped up with the crane or discharged with a suction pipe and so comes to lie in the body of water and, when the body of water is in motion and/or if there is current flow, can be dispersed over great distances. Even if such dislodged bottom material is not spread over a considerable distance, deposition thereof will occur.

A reason for dredging or deepening is that a body of water has become insufficiently deep. Deposited bottom material released during dredging or deepening and coming down at a distance from the dredging or deepening or close thereto reduces the effectiveness of the dredging or deepening. Cases are even known in which a desired degree of dredging or deepening is not achieved with known installations. Contractors carrying out the dredging or deepening work may thus find themselves in a situation where the work has to be done again if pre-agreed criteria are not fulfilled. In order to avoid such situations it has become common practice for contractors to prepare such work such that the dredging or deepening has to be carried out right from the start to a depth greater than that agreed upon with a client in order to avoid later arguments. This has ecological consequences as well as technical and commercial drawbacks, since disposal of more bottom material from dredging or deepening than necessary also results in higher processing costs and transport costs. The essence of the problem is therefore that it is not possible with known installations to dredge or deepen with sufficient precision.

Known from US-2002/133983 is a vessel from which sheet-like elements can be lowered and raised in order to define a work area. The sheet-like elements are similar to sheet-pile profiles. Each of these sheet-pile profiles has to be driven individually in order to be raised or lowered, taking into account unevenness in the bottom of the body of water.

Known from JP-2005.068930 and JP-H02.128008 are vessels from which foil, cover or film can be lowered in order to enclose a work area and raised again following the work operations. Foil, cloth and film are susceptible to currents.

The present invention has for its object to obviate or at least considerably reduce problems of the known techniques, for which purpose an installation for dredging or deepening a bottom in or of a body of water according to the invention has the combination of features and measures of: at least one float; a dredger crane or a suction pipe; and a screen which in use can be positioned adjacently of an operational area of the dredger crane or the suction pipe or at least upstream thereof relative to a flow direction in or of the body of water, and in use prevents the dispersal of bottom material dislodged during dredging with the dredger crane or suctioning with the suction pipe or deepening of the bottom, wherein the float is selectively lowerable and dimensioned to be lowered onto or into the bottom of the body of water, and in lowered position forms the screen.

The operational area of the dredger crane or suction pipe is related to the range of the crane or suction pipe when employed from a substantially stationary position on the body of water. The float itself serves here to screen or delimit this operational area, whereby dislodged bottom material can be prevented from floating away and being deposited. In operative mode this float will have to connect as closely as possible to the bottom of the body of water in order to prevent the escape of dislodged bottom material. The float is preferably lowered at least to some extent into the bottom. When dredging operations in an operational area defined by the float or the dredger crane or the suction pipe have been completed, the float can be dragged in a lowered position through or along the bottom to a new operational area. It is also possible for the float to be moved upward from or out of the bottom, although this can in turn have consequences in terms of dislodged bottom material being released. The float is preferably dragged on or through the bottom to a new operational area, although not precluded from protection is that the float is moved out of or away from the bottom for displacement from one operational area to another. For transport of the installation from and to a location where the dredging operations have to be performed it must in any case be possible to bring the float into a floating position in order to reduce kinetic resistance thereof relative to the dragging of a wall or other lowered element through or along the bottom. A float in the sense of the present invention is therefore designed and/or configured to be able to float, but in any case to be able to be lowered onto or into the bottom in an operational area. For a floating transport position the float can be equipped with tanks, such as ballast and air tanks, to selectively enable a floating or lowered position of the float to be realized. This results in a simple driving for realizing an operative mode connecting to the bottom or protruding therein in order to form the screen and/or allowing the float to float.

In a river or other flowing body of water it is recommended that the float can surround or delimit the whole operational area, and is then for instance U-shaped or O-shaped, although screening the body of water from flow or movement may already suffice, for instance in a body of water with still water, if the float is an elongate and displaceable wall, wherein the dredger crane at or the suction pipe along or adjacently of this wall can be set into operation.

The present invention thus has many preferred embodiments, several of which arc discussed in the figure description following below of a limited number of embodiments and which can have features according to the dependent claims of the appended claims. In anticipation of the figure description following below and the subsequent claims, it is also noted here that the dependent claims and the specific embodiment in the figures relate only to non-imitative embodiments of possible installations according to the present invention.

A possible embodiment of an installation according to the present invention can have the feature that the dredger crane or suction pipe is arranged on or at the float or on or at a vessel separate from the float.

An additional or alternative embodiment of an installation according to the present invention can have the feature of a reservoir on or at the float or on or at a vessel separate from the float for the purpose of collecting bottom material from dredging or deepening.

All these and other configurations fall within the scope of the present invention, irrespective of whether a separate barge is provided solely for disposal of bottom material or also to provide a platform for a dredger crane or suction pipe. The separate barge can even be dispensed with when use is made of a suction pipe and for instance discharge means comprising pipes for transport of bottom material to a location for processing thereof.

An additional or alternative embodiment of an installation according to the present invention can have the feature that the float comprises at least two floating bodies. Together these floating bodies can define a screening range corresponding to the operational area. It is also possible to follow inclinations occurring in a bottom of a body of water by controlling the floating bodies individually in respect of lowering thereof. In such an embodiment with at least two floating bodies the installation can further have the feature that the floating bodies are elongate and disposed substantially parallel to each other. A substantially rectangular operational area is thus formed or defined by the installation, and more particularly by the floating bodies thereof. It is noted that other shapes of operational area are also possible within the scope of the invention.

An additional or alternative embodiment of an installation according to the present invention can have the feature of a scraper on or at an underside of the float. This feels as if it runs counter to the wish to prevent the dispersal of dislodged bottom material, but, particularly in combination with an embodiment of an installation with a float close to or even in the bottom of the body of water, also during displacement thereof, such a scraper can pick up local

accumulations of bottom material during displacement of the installation and carry it to a subsequent operational area in the succession of operational areas for processing, so that it can there be discharged using the dredger crane or suction pipe. Measurements following completion of the dredging operations, if accidentally taking place at a remaining accumulation of bottom material, cannot therefore result in the obtained result not being approved by a client on the basis of an incidental or local accumulation. It is also possible here by way of example for the scraper to be adjustable in angular position in order to pick up a remnant of an intended quantity of bottom material from dredging or deepening during displacement of the installation. Particularly in an embodiment in which the scraper can be placed at an angular position protruding under the float, this scraper can even correct a result of the dredging operations which is in itself unsatisfactory. An adjustable angular position can preferably be realized in that a drive is provided between the float and the scraper for the purpose of controllable adjustment of the angular position of the scraper relative to the float. The degree of correction by the scraper of the result achieved by dredging operations can thus be adjusted remotely or on the installation.

Tn an embodiment of an installation according to the invention with a scraper the installation can have the feature that the scraper comprises a plate arranged pivotally on the float. In an embodiment with a drive use can for instance be made of a hydraulic or pneumatic cylinder or any other random form of drive. A pivotable plate as embodiment of a scraper is an effective, elegant and simple manner of improving results of dredging operations during displacement of the installation. For this particular puipose the installation can have the feature in a further developed embodiment that the plate has at least approximately the same dimensions as a width of the float. Since the float defines the operational area in combination with the range of a dredger crane or suction pipe, remnants from dredging or suction will be carried along by the scraper up to an intended depth over the full width of the operational area.

An additional or alternative embodiment of an installation according to the present invention can have the feature of a levelling plate on or at an underside of the float. In an embodiment combined with a scraper, such a levelling plate extends in an opposite direction relative to the scraper. A levelling plate can also be provided without a scraper also being arranged on the float. A bottom surface of the float in combination with a levelling plate can fulfil a substantially similar function to that of a scraper or additionally fulfil a levelling function at the bottom of the body of water.

In an embodiment with a levelling plate an installation according to the present invention preferably further has the feature that the levelling plate has at least the same dimensions as a width of the float.

An additional or alternative embodiment of an installation according to the present invention can have the feature that the float has a form substantially enclosing the operational area of the dredger crane or suction pipe. The float can here be U-shaped. As already noted above, a single floating body can already provide an effective screening depending on the conditions of flowing or still water and other considerations. If the installation is designed to surround or delimit the operational area with the float, this is also understood to mean the U-shape of the float consisting of one, two or three or more floating bodies, partitions and plates.

The installation can have a GPS positioning system to enable adjacent operational areas to be determined and successively processed with the installation.

The present invention is further elucidated hereinbelow on the basis of embodiments thereof shown in the accompanying drawing, wherein the same or similar elements and/or components can be designated with the same reference numerals, wherein it should be noted that the embodiments shown in the drawing are only non-imitative embodiments. In the drawing:

Figure 1 is a perspective view of a U-shaped installation according to the present invention in operation;

Figure 2 is a cross-sectional view along the line II-II in figure 1 ;

Figure 3 is a perspective view in the direction of arrow ITT in figure 1 ;

Figure 4 is a side view corresponding with figure 2 of an installation according to the invention during displacement thereof; and

Figure 5 shows an alternative embodiment of an installation according to the present invention closed around an operational area.

Figure 1 shows an installation 1 according to the present invention in a possible embodiment thereof. Installation 1 comprises a float or pontoon 2 with two floating bodies 3.

Floating bodies 3 are disposed parallel, wherein a partition or wall 5, 6 is arranged at an outer end thereof for the purpose of connecting floating bodies 3. In the embodiment of an installation 4 in figure 5 partitions or walls 5 are arranged at both longitudinal outer ends of floating bodies 3. In each of the two embodiments of figures 1 and 5 the installations 1 , 4 define an enclosed operational area 7, for instance for a dredger crane 8. A suction pipe (not shown) could be provided as alternative to dredger crane 8. Dredger crane 8 is arranged on a barge 9 which further comprises a reservoir or receptacle 10 into which is placed bottom material scooped out of operational area 7 of bottom 11 of body of water 12 using dredger crane 8. Dredger crane 8 can optionally also be arranged on pontoon 2 instead of on barge 9 as shown in figure 1. Pontoon 2 with floating bodies 3 is can be lowered in order to rest on bottom 11 of body of water 12.

As shown in figure 2, floating bodies 3 of pontoon 2 can be lowered into bottom 11 ar ound an operational area 7 for dredger crane 8. A good isolation of operational area 7 is hereby achieved with certainty, even in the case of a strong current of the water in body of water 12.

Thrown-up bottom material cannot escape from operational area 7, or hardly so.

Bottom material can be excavated from bottom 11 to an exact desired depth using dredger crane 8. When dredger crane 8 has finished excavating bottom 11 in the operational area 7 enclosed by the float or pontoon 2, float or pontoon 2 can be displaced in the direction of arrow A in figure 3, for instance using barge 9 in figure 1, or another random vessel.

A scraper embodied as pivotable plate 14 is arranged on the underside of partition or wall 5. An angular position of this scraper can be adjusted using a hydraulic cylinder 13. During displacement of the float or pontoon 2 in the direction of arrow A, and with the scraper or pivotable plate 14 in the position thereof shown in figure 3, bottom material will be deliberately thrown up in the direction of arrow B from bottom 11. When the float or pontoon 2 comes to rest after displacement in the direction of arrow A, underwater dunes 15 in figure 4 will be scraped away to the new level of bottom 11 by pivotable plate 14. A levelling plate 16 is arranged on the side of the partition or wall 5 opposite that of the scraper or pivotable plate 14. Just as the scraper, it is arranged on the underside of the partition or wall 5 but, in contrast to the scraper, is connected in substantially stationary and stable manner to the partition or wall 5 via a shore 17. Levelling plate 16 can extend downward to some extent relative to the lower edge of the partition or wall 5. Scraper 14 scrapes away dunes 15 and unevenness, and levelling plate 16 contributes further toward the levelling of the resulting surface of bottom 11. This makes it possible to remove bottom material from bottom 11 with a high degree of precision. It is not necessary to excavate deeper than required in order to comply with agreements with for instance a client.

Figure 1 further shows that a GPS receiver 18 is arranged on the float or pontoon 2. This makes it possible for a control (not shown) - for instance in a cabinet 19 of barge 9 - to precisely determine a position of the float or pontoon 2. It is thus also possible for very accurate displacement of the float or the pontoon in the direction of arrow A in figure 3 to take place over precisely a distance corresponding to a length of the float or pontoon 2 in the direction of this arrow A. During movement transversely of this direction the float or pontoon 2 can first be lifted out of or from bottom 11. The displacement is ended when the operational area 7 defined by the float or pontoon 2 lies precisely adjacently of a previous, already processed operational area of bottom 11.

Reference has already been made in the foregoing to diverse additions and alternatives to the features of the embodiments as shown in the accompanying drawing. These and other additions and alternatives, which will immediately occur to the skilled person after examination of the foregoing, must be deemed as lying within the scope of protection of the present invention in accordance with the definitions thereof in the appended claims. Reference is thus made for instance to a shown dredger crane and a suction pipe is described as alternative, although other implements can also be used within an operational area to perform excavation or suctioning or other operations on the operational area within the limitations of the float or the pontoon. The shown walls or partitions 5, 6 can also be embodied as floating bodies and for instance comprise tanks for influencing the buoyancy of the pontoon or the float.

Claims

1. An installation for dredging or deepening a bottom in or of a body of water, at least comprising:

- at least one float;

- a dredger crane or a suction pipe; and

- a screen which in use can be positioned adjacently of an operational area of the dredger crane or the suction pipe or at least upstream thereof relative to a flow direction in or of the body of water, and in use prevents the dispersal of bottom material dislodged during dredging with the dredger crane or suctioning with the suction pipe or deepening of the bottom,

characterized in that

the float is selectively lowerable and dimensioned to be lowered onto or into the bottom of the body of water, and in lowered position forms the screen.

2. The installation as claimed in claim 1 , wherein the dredger crane or suction pipe is arranged on or at the float or on or at a vessel separate from the float.

3. The installation as claimed in claim 1 or 2, further comprising: a reservoir on or at the float or on or at a vessel separate from the float for the purpose of collecting bottom material from dredging or deepening.

4. The installation as claimed in one or more than one of the foregoing claims, wherein the float comprises at least two floating bodies.

5. The installation as claimed in claim 4, wherein the floating bodies are elongate and disposed substantially parallel to each other.

6. The installation as claimed in one or more than one of the foregoing claims, further comprising a scraper on or at an underside of the float.

7. The installation as claimed in claim 6, wherein the scraper is adjustable in angular position in order to pick up a remnant of an intended quantity of bottom material from dredging or deepening during displacement of the installation.

8. The installation as claimed in claim 7, further comprising a drive between the float and the scraper for the purpose of controllable adjustment of the angular position of the scraper relative to the float.

9. The installation as claimed in at least one of the foregoing claims 6-8, wherein the scraper comprises a plate arranged pivotally on the float.

10. The installation as claimed in claim 9, wherein the plate has at least approximately the same dimensions as a width of the float.

11. The installation as claimed in one or more than one of the foregoing claims, further comprising a levelling plate on or at an underside of the float.

12. The installation as claimed in claim 11, wherein the levelling plate has at least the same dimensions as a width of the float.

13. The installation as claimed in one or more than one of the foregoing claims, wherein the float has a form substantially enclosing the operational area of the dredger crane or suction pipe.

14. The installation as claimed in claim 13, wherein the float is U-shaped.

15. The installation as claimed in one or more than one of the foregoing claims, further comprising: a GPS positioning system.