DK2930275T3

DK2930275T3 - System and method for making a foundation for a building in water

Info

Publication number: DK2930275T3
Application number: DK14001284.0T
Authority: DK
Inventors: Marc Dr Peters; Ulrich Schaffhauser
Original assignee: Herrenknecht Ag
Priority date: 2014-04-08
Filing date: 2014-04-08
Publication date: 2018-04-03
Also published as: EP3333324A1; EP2930275B1; EP2930275A1

Description

The invention relates to a method and a system for producingafoundation for abuilding in water.

Such a method and such a system are known from EP 2500473 B1. Here, a platform is arranged at a foundation site and has a guide element for a monopile to be introduced. The monopile is introduced into the ground and the annular space between the monopile in the ground is subsequently filled. As a first variant, the monopile is introduced directly, on which monopile a wind turbine is then installed via a connecting section. Alternatively, as a second variant, the foundation structure is divided into two parts in which a monopile is first introduced, in which a second tubular element is subsequently positioned, on which the connection adapter, and in turn the wind turbine, are then placed. As a third variant, a permanent formwork is first introduced into the ground into which formwork the monopile is then positioned, on which monopile the connection adapter and the wind turbine are then placed. In order to be able to carry out the methods described above, a jack-up platform or a comparable carrier vehicle is provided at the foundation site with which the monopile can in particular be guided when it is being introduced. The use of such jack-up platforms is expensive. EP 2527539 A1 discloses an underwater drilling arrangement and a method for introducing a foundation element into a bed of a body of water. The underwater drilling arrangement comprises a submersible working platform for placement onto the bed of a body of water. It has a guide pipe for receiving and guiding the drilling tool. The underwater drilling arrangement is supplied via a supply line with energy, flush liquid and/or hardening mass, in particular concrete, from a supply vessel. The guide pipe is supported on the working platform in a displaceable and rotatable manner. The guide pipe is screwed into the ground as an additional anchor of the working platform. On its underside, the guide pipe has a cutting device. A drilling apparatus for creating the borehole is then arranged in the guide pipe. After the borehole has been created, the drilling apparatus is removed and the foundation pile is introduced through the guide pipe into the borehole and anchored with concrete. The guide pipe is removed from the ground again and lifted off the bed of the body of water together with the working platform. EP 256248 A1 discloses a drilling apparatus for creating a bore in abed of a water body. A working platform is set down on the bed of the body of water. A guide pipe is provided in the working platform. On its underside, the guide pipe has a cutting device. Furthermore, a drilling apparatus is provided in connection with the working platform, said drilling apparatus being movably arranged in the guide pipe. The guide pipe itself is arranged so as to be adjustable relative to the working platform, so that it can be lowered relative to the working platform. As a result, a greater drilling depth can be reached. The guide pipe itself can be introduced into the ground via the cutting device. The guide pipe and the drill head can be alternately introduced into the ground in a stepwise manner. The loosened ground material is removed from the borehole. After the bore has been created, the working platform is removed again with the guide pipe from the bed of the body of water. The drilling apparatus is used to create boresfor the foundation piles of wind turbines. A practical application of the method and system described above is disclosed on pages 139 to 149 of the Communications of the Institute and Laboratory of Geotechnics at Technische Universitåt Darmstadt (Darmstadt University of Technology), Issue No. 91,2012.

In order to be able to use the methods and apparatuses described above, a supply ship must be present at the foundation site for the entire period over which the foundation is created, the use of which is expensive.

The object of the invention is therefore to improve the aforementioned method in such a way that it can be carried out more cost-effectively.

In order to achieve the object according to the invention with regard tothemethod,the invention provides a method in which a guide apparatus is set down on the surface of the bed of the body of water at the foundation site, a casing is arranged in the guide apparatus on the bed of the body of water in the direction of introduction, a drilling apparatus is arranged in the casing, a cavity is generated in the ground of the body of water beneath the casing by virtue of the ground being removed by means of the drilling apparatus, the casing is lowered into the cavity until an envisaged end depth in the ground is reached, the drilling apparatus is then removed from the casing, a foundation element is introduced and lowered into the cavity in the interior of the casing, and the interspace between the cavity wall and the outer side of the foundation element is filled, wherein the casing is removed from the cavity once the foundation element has been introduced, and wherein the guide apparatus and the casing are separately removable from one another. A separation of the guide apparatus from the platform has proven to be advantageous, since it is thereby possible to carry out the method in a plurality of sections. In a first section, the guide apparatus is therefore set down as a separate unit on the surface of the bed of the body of water. The tubular casing, which functions as a type of casing, is then inserted into this guide apparatus. The drilling apparatus, which then removes the ground in the foundation region, is introduced into the casing.

Where appropriate, the casing is introduced into the casing thereby produced in a controlled manner by the guide apparatus. Once the casing has been introduced into the ground down to its end depth, the drilling is ended and the drilling apparatus is removed from the casing. Due to the provision of this casing, it has proven to be possible, in a second method step, to then introduce the monopile into the casing, to remove the casing and afterwardsto fill the cavity between the cavity wall and the outer wall of the foundation element. After the hardening of the filling material and the associated fixing of the foundation element in the ground, the guide element can be removed.

As a result, it is possible in a simple manner to divide the method described in the prior art into a plurality of sections which can be carried out cost-effectively by a plurality of units. It is thus possible, in a region in which a plurality of structures are to be erected, to perform all the bores with a first unit in order then to be able to erect the individual structures much more quickly with a second unit. A further teaching of the invention provides that the guide element is removed before or after the foundation element is introduced into the casing. Furthermore, it is advantageous that the casing is closed by aclosure element once the drilling apparatus has been removed, wherein the closure element is removed preferably prior to the foundation element being introduced, and/or the closure element is preferably a cover. By closing the casing, it is possible to close the casing in particular in bodies of water with strong currents or a large proportion of sediment in order to prevent material from entering in a simple manner. A further teaching of the invention provides that a cement-containing material is used to fill the cavity between the cavity wall and foundation element. As a result, it is possible in a particularly simple manner to achieve an appropriate fixing of the foundation element in the ground. Furthermore, it is advantageous that the foundation element is a pile. Furthermore, it is advantageous that the structure is a wind turbine.

With regard to the system, the solution according to the invention provides a system, preferably according to the method described above, having a guide apparatus which can be set down on the surface of the bed of the body of water at the foundation site, having a casing which can be arranged in the guide apparatus on the bed of the body of water in the direction of introduction, having a drilling apparatus, which can be arranged in the casing and is suitable for generating a cavity in the ground of the body of water beneath the casing by virtue of removing the ground by means of the drilling apparatus, the casing being lowered into said cavity and being removable therefrom once the foundation element has been introduced, having a foundation element which can be introduced and lowered into an inner space in the interior of the casing, and having a filling material which is suitable for filling a cavity which is present between the cavity wall and the outer side of the foundation element once the casing has been removed, wherein the guide element and the casing are separately removable from one another.

An advantageous embodiment of the invention provides for the provision of a closure element by means of which the casing can be closed. This is preferably a cover. A further teaching of the invention provides that the foundation element is a pile, and/or that the filling material is a cement-containing material.

The invention is explained in more detail below with reference to drawings, in which Figs. 1 to 15 show the individual method steps according to the invention and the system according to the invention.

At a foundation site 10 for an offshore structure in the form of a wind turbine 100, a guide apparatus 13 is arranged in the water 11 on the bed 12 (see Fig. 1). The guide apparatus 13 has a pipe section 14, which is connected to aflat support body 15 on the bed of the body of water 12. For support purposes, diagonal struts 16 are arranged between the pipe section and the support body. As illustrated in Fig. 2, a casing in the form of a casing 18 is arranged in the inner space 17 in the pipe section 14. As illustrated in Fig. 3, a drilling apparatus20 is arranged in the inner space 19 of the casing 18. The ground 22 to be loosened which is located in the removal region is removed by means of a drill head 21 of the drilling apparatus 20. This results in a cavity 23 into which, as the drilling progresses (see Fig. 4), the casing pipe 18 is lowered into the cavity 23.

Once the cavity 23 has been drilled to the corresponding depth by the drilling apparatus 20 (see Fig. 5) and the casing pipe has been lowered correspondingly to the cavity bottom 24, the drilling apparatus 20 is removed from the inner space 19 of the casing 18.

As illustrated in Fig. 6, to close the inner space 19 of the casing 18, a cover element 25 can subsequently be applied on the end 26 of the casing projecting into the body of water 11, so that the inner space 19 is then closed off against material entering by means of inflowing water. The foundation site 10 thus prepared can now remain in the state illustrated in Fig. 6, until the subsequent steps for erecting the structure 100 are carried out. For this purpose, as illustrated in Fig. 7, the cover 25 is removed and subsequently, as illustrated in Fig. 8, a foundation pile 27 is introduced into the inner space 19 of the casing 18 and set down on the cavity bottom. The casing pipe 18 is subsequently withdrawn from the cavity 23, as illustrated in Fig. 9, so that the pile remains in the cavity 23 and in the inner space 17 of the guide apparatus 13. Between the outer wall 29 of the cavity 23 and the outer wall 28 of the foundation pile 27, there is thus an annular space 30 (see Fig. 10). A filling material 31 is introduced into the annular space 30 and the water previously located in the annular space 30 isthereby displaced. This is continued until the filling material 31 in the annular space 30 has reached the height of the bed of the body of water 12. After the filling material 31 has hardened, the guide apparatus 13 is then removed and the foundation pile 27, starting from the bed of the body of water 12, stands freely in the body of water 11. A connecting element 32 is then arranged on the foundation pile 27 (see Fig. 14), on which connecting element the wind turbine 100 (see Fig. 15) is then erected.

Claims

A method of manufacturing a foundation for a structure in water, wherein a guide device (13) is placed on the waterbed surface at the foundation site (10), a sheath (18) is placed in the guide device (13) on the waterbed (12) in the direction of application, a drilling device (20) is placed in the casing (18), a cavity (23) is generated in the water floor below the casing (18), thereby removing the bottom by means of the drilling device (20), the casing (18) being lowered into the cavity (23) until a predetermined the bottom depth is reached, then the drilling device (20) is removed from the sheath (18), a foundation element (27) is inserted and lowered into the cavity in the interior (19) of the sheath (18), and the space (30) between the cavity wall (29). ) and the outer side (28) of the foundation element (27) is filled where the sheath (18) is removed from the cavity (23) as soon as the foundation element (27) has been inserted and where the guide device (13) and the sheath (18) can be removed separately. apart.

Method according to claim 1, characterized in that the guide element (13) is removed before or after the foundation element (27) is inserted into the sheath (18).

Method according to claim 1 or 2, characterized in that the sheath (18) is closed with a closure element (25) as soon as the drilling device (20) has been removed, the closure element (25) being preferably removed prior to the insertion of the foundation element (27). and / or the closure element (25) is preferably a cover.

Method according to one of claims 1 to 3, characterized in that a cement-containing material (31) is used to fill the cavity (30) between the cavity wall (29) and the foundation element (27).

Method according to one of claims 1 to 4, characterized in that the base element (27) is a post.

Method according to one of claims 1 to 5, characterized in that the structure (100) is a wind turbine.

A system for making a foundation for a structure in water, preferably using a method according to one of claims 1 to 6, with a guide device (13) which can be applied to the water surface (12) at the foundation site (10) with a sheath (18) which can be placed in the guide device (13) on the waterbed (12) in the direction of application, with a drilling device (20) which can be placed in the sheath (18) and is suitable for generating a cavity (23) in the waterbed (12) under the sheath (18) by virtue of removal of the bottom (22) by means of the drilling device (20), the sheath (18) being lowered into said cavity and which sheath (18) being removable therefrom as soon as the foundation element (27). ) has been inserted, with a base element (27) which can be inserted and lowered into an inner space (19) in the interior of the sheath (18), and with a filling material (31) suitable for filling a cavity (30) present between the cavity wall (29) and the outside of the foundation element (2) 7) as soon as the sheath (18) has been removed, the guide element (13) and the sheath (18) being separately removed from each other.

System according to claim 7, characterized in that the provision of a closure element (25), by means of which the sheath (18) can be closed.

System according to claim 7 or 8, characterized in that the foundation element (27) is a post and / or that the filling material (31) is a cement-containing material.