DK2441892T3

DK2441892T3 - Device and method for the insertion of the pile in the seabed

Info

Publication number: DK2441892T3
Application number: DK11184911.3T
Authority: DK
Inventors: Bernhard Weyres
Original assignee: Bernhard Weyres
Priority date: 2010-10-14
Filing date: 2011-10-12
Publication date: 2015-12-14
Also published as: EP2441892A2; EP2441892B1; DE102010048474A1; EP2441892A3; PL2441892T3

Description

Description [0001] The invention relates to a device and a method for introducing piles into the seabed according to the preamble of claim 1 and the preamble of claim 13, respectively. Such devices and methods are used in particular for introducing into the seabed a cylindrical hollow pile which as a so-called monopile structure is the foundation of a wind mill of an offshore wind park or of a measuring tower. Such monopile structures are particularly suitable for foundations in water depths up to about 20 m. Greater water depths up to 45 m are conceivable. In addition, jacket, tripile or tripod structures are known for greater water depths, which are, however, also anchored in the seabed by means of cylindrical, hollow piles.

[0002] Such ram piles can be installed easily and fast. However, a drawback is that the erection requires heavy pile-driving equipment which fills the environment with loud acoustic noise that is particularly detrimental to the marine fauna.

[0003] Therefore, EP 1 989 358 B1 proposes to surround the pile to be introduced into the seabed by at least one sound-absorbing solid socket which is flooded with seawater. This known sound-protection socket is designed in such a way that the entire pile-driving machine is accommodated in the socket. This sound-protection socket is disadvantageous because it has a relatively large inner diameter which has to be larger than the maximum outer diameter of the machine. Furthermore, the sound-protection properties are not sufficient to create good sound protection for the marine fauna.

[0004] WO 2007/150028 A2 discloses a sound protection element made from a textile material. It comprises two nonwoven material layers which enclose a plurality of hoses. During operation, compressed air is applied to the hoses, thus forming a stationary bubble curtain.

[0005] JP 1 142 123 A shows two half shells which are made from metallic material and are lined with rubber. A plurality of said half shells shall be attached to the pile to be introduced by means of clamping. When the pile is introduced into the seabed, the respectively lowermost half shell is removed again. This sound protection element is also insufficient as regards the effect and in addition requires the employment of divers working in deep water.

[0006] Therefore, the object of the invention is to provide a device and a method for introducing piles into the seabed, which offers sufficient sound protection and has relatively small dimensions.

[0007] The invention is achieved by means of a device according to the features of claim 1 and a method according to the features of claim 13. Advantageous embodiments of the invention are specified in the dependent claims.

[0008] According to an embodiment of the invention, a sound protection device according to claim 1 and a method according to claim 13 are provided, wherein a bubble curtain is provided between the socket and the pile to be introduced into the seabed and at least one further socket is available which surrounds the first socket, wherein sound-absorbing material is present between the two sockets, said material containing or consisting of shredded scrap rubber. This embodiment of the invention renders possible, on the one hand, a guidance or localization of the bubble curtain, as a result of which said curtain cannot drift away with the sea current. On the other hand, the sound-absorbing material can further reduce the sound level.

[0009] According to an embodiment of the invention, a sound protection device according to claim 1 and a method according to claim 13 are provided, wherein the sound protection device has at least one sound protection socket extending into the seabed. As a result, a sound-proof or at least sound-absorbing closure is obtained in the area which is surrounded by the socket and faces the seabed.

[0010] According to an embodiment of the invention, a sound protection device according to claim 1 and a method according to claim 13 are provided, wherein the interior of the socket is provided with guide rollers for guiding the pile to be introduced into the seabed. This embodiment of the invention makes it easier to introduce the pile in a determinable direction, e.g. perpendicular, by initially aligning the sound protection element on the sea bottom where it is fixed before the driving work starts. As a result of the guide rollers, it is possible in some embodiments of the invention to avoid a contact between pile and wall so as to minimize the structure-borne noise transmission.

[0011] In some embodiments of the invention, the socket can be formed of at least two half shells so as to make possible an easy assembly and disassembly.

[0012] In some embodiments of the invention, the socket can be assembled in an axial direction from several elements. The elements can have different lengths, and therefore the sound protection element and/or the method can be used in a flexible way in different water depths.

[0013] In some embodiments of the invention, the guide rollers can have a vibration-damping coating, preferably a rubber coating, and therefore the structure-borne noise transmission can be further minimized.

[0014] In some embodiments of the invention, a plurality of guide roller layers can be provided along the axial direction of the device.

[0015] In some embodiments of the invention, another socket can be provided which surrounds the socket receiving the sound-absorbing material and receives a bubble curtain.

[0016] In some embodiments of the invention, a further socket can be provided, which surrounds the socket receiving the bubble curtain, wherein a soundabsorbing material is arranged between the socket receiving the bubble curtain and the further socket.

[0017] In some embodiments of the invention, a frame construction can be arranged around the outer socket.

[0018] According to the invention, the sockets can be made as half shells which are preferably separated from one another by separating surfaces.

[0019] In some embodiments of the invention, the separating surfaces can be provided with extensions for the acoustic separation.

[0020] According to an embodiment of the invention, a method according to claim 13 is provided, wherein the pile to be introduced is surrounded by a soundabsorbing socket, wherein when the pile is driven in, it is guided by guide rails which are arranged between the socket and the pile, and a bubble curtain is provided between the solid socket and the pile to be driven into the bottom, and a further socket is provided which is arranged around the first socket and receives sound-absorbing material, and a sound protection socket is introduced into the seabed, said socket surrounding the pile.

[0021] In some embodiments of the invention, a further bubble curtain can be provided in another socket which surrounds the further socket.

[0022] In some embodiments of the invention, another socket can be provided around the socket receiving the second bubble curtain, wherein a soundabsorbing material is provided between the socket receiving the second bubble curtain and the outer socket.

[0023] The invention is not only suitable for introducing monopiles into the seabed but can also be used advantageously for introducing tripiles, tripods or jackets. Tripods are used for constructions where the construction is mounted on three piles anchored in the seabed. Jackets are frame constructions which are anchored on four piles introduced into the seabed.

[0024] The invention also provides an offshore sound protection device according to claim 1 for driving work under water, comprising at least one and preferably a combination of the following features: • The sound protection device is made as a half shell design. The advantage is that the pile to be introduced into the seabed is placed on the bottom of the sea and the sound protection device can be arranged around the pile. In other words this means that the sound protection device does not have to be put over the pile from above. As a result, the advantage is that the crane structures used do not have to be so high. • The sound protection device has a structure having several walls or sockets, preferably at least four walls. The advantage is that various means can be used for sound insulation. Bubble curtain and sound insulating material preferably alternate. The at least quadruple wall structure makes possible e.g. a double bubble curtain and a double sound absorption. Such a structure can reduce the sound to a value of below 135 dbA under water. • A double bubble curtain is provided. The bubble curtains are preferably separated from one another by a sound absorption. Each of the bubble curtains is provided between two walls or between the pile to be introduced and a wall. • At least two nested absorption elements are provided which are preferably separated from one another by a bubble curtain. The absorption is always arranged in a double pipe between two walls. • The absorption shells can be submerged into the seabed by means of a rubber pad. • Where appropriate, a conical structure might be provided for underwater driving. • A modular system can be provided which results in a segmental construction. The advantage is that the system can easily be adapted to various water depths. For example, segments having a length of 20 m, 16 m and 9 m can be provided. In this way, piles can easily be introduced into the seabed at water depths of 9 m, 16 m, 20 m, 25 m, 29 m, 36 m and 45 m with three different segments. This serves for reducing the costs considerably. • The piles to be introduced into the seabed are guided in the inner wall by means of guide rollers. The guide rollers preferably have rubber rollers. As a result, the driving vibrations can be considerably reduced. • The device can preferably be altered to realize different pipe diameters. • The segments have flange connections for mounting segments serving for an extension to be used in various water depths.

[0025] The invention is shown below by means of an exemplary embodiment of the invention, illustrated in the figures.

Figure 1 shows a schematic sectional view of a device according to the invention, wherein the outer frame construction is shown in perspective, along line l-l of figure 2.

Figure 2 shows a schematic sectional view of the device according to the invention of figure 1 along line ll-ll of figure 1: [0026] The following reference signs are used in the description: 1 pile 2 seabed 3 water surface 4 driving direction 5 support 10 guide roller 11 rubber coating (vibration-absorbing) 13 fork 20 socket 21 half shell 22 half shell 23 bubble curtain 30 socket 31 half shell 32 half shell 33 sound-absorbing material 40 socket 41 half shell 42 half shell 43 bubble curtain 50 socket 51 half shell 52 half shell 53 sound-absorbing material 60 frame construction 61 side member 62 side member 63 side member 64 side member 68 lower part 69 upper part 70 separating device 71 separating surface between the half shells 72 acoustic separation 81 bubble inlet opening 82 bubble outlet opening 83 bubble inlet opening 84 bubble outlet opening 91 sound protection socket 92 sound protection socket [0027] The device for introducing a pile 1 into the seabed 2 has a modular or segment-like design. An outer frame construction 60 extends from the seabed 2 to the water surface 3; the frame construction 60 is divided into three sections 60A, 60B and 60C. In the exemplary embodiment shown, the upper section 60A has a dimension of about 25 m, the middle section 60B has a dimension of about 16 m and the lower section 60C has a dimension of about 9 m. Separating devices 70 are provided between the sections. The frame construction 60 has connection flanges for attachment in the separating devices 70. The frame construction 60 has a fixation 73, by means of which it is anchored in the seabed 2. The bottom plate 73 comprises openings 81 and 83 by means of which bubble curtains 23, 43 can be produced for sound absorption. The openings 81,83 are arranged in concentric fashion around the pile 1. For example, 10, 20 or more openings 81,83 can be provided. The air required for generating the bubble curtain 23, 43 can be inserted from above by means of a hose.

[0028] The sections of the sockets can be connected to one another by providing, at the end of the sockets, flanges where the sockets are connected or bolted to one another to form a longer socket.

[0029] The device for sound absorption has several sockets 20, 30, 40, 50 which are arranged concentrically around the pile 1 to be introduced and which are disposed around the pile 1 in a substantially concentric fashion. The sockets 20, 30, 40, 50 are formed in each case of 2 half shells 21,22 or 31,32 or 41,42 and 51,52. The half shells of the sockets 20, 30, 40, 50 are attached to the separating devices 70 in a way known to a person skilled in the art so as to create a full socket which encloses the respectively inner socket or the pile to be produced. For example, the half shells can have longitudinal flanges where the half shells can be bolted together. Guide rollers 10 are arranged inside the innermost socket 20. The guide rollers 10 have an outer rubber coating which has a dual function, namely to both introduce the pile 1 and absorb the sound during driving. In contrast to the prior art, guide rollers 10 are used, as a result of which the pile does not glide with respect to the guides during driving but the guide rollers 10 roll along the pile to be introduced when driving in the direction of the arrows 4, which indicate the driving direction for the pile 1.

[0030] A bubble curtain 23 is provided inside the innermost socket 20. In order to produce the bubble curtain 23, air or gas is introduced through openings 81 provided at the lower part 68 of the frame construction 60. The air can e.g. be guided through a hose running in the frame construction 60 outside the outermost socket 50 to the openings 81. Corresponding openings 82 are provided at the upper part 69, where the air of the bubble curtain can escape again. Another socket 30 is provided around the innermost socket 20. Sound absorbing material 33 is introduced between socket 30 and socket 20. Another socket 40 is provided around the socket 30. Another bubble curtain 43 is provided in the space between the further socket 40 and the socket 30. The bubble curtain 43 is formed by introducing air or gas through holes 83 provided in the lower part 68 of the frame construction 60. In the upper art 69 of the frame construction, holes 84 are provided for the escape of the air required for producing the bubble curtain 43. An outer socket 50 is provided which encloses the further socket 40. Sound absorbing material is provided between the outer socket 50 and the further socket 40.

[0031] For example, 1000 holes 83 or 84 having a diameter of about 2 to 3 mm can be provided in each case. Bubbles having a diameter of 3 to 4 cm can be produced by adjusting a suitable pressure, and therefore the bubble curtain has an air content of about 30 to 40 %. According to an alternative embodiment of the invention, an air chamber can be provided for sound absorption instead of the bubble curtain 43. Alternatively, the space between the socket 40 and the socket 30 can also be a vacuum to achieve an even better sound insulation, e.g. a coarse vacuum or a fine vacuum. Where appropriate, the flanges joining sockets 30 and 40 can be connected to one another by interposing a vibration damping device.

[0032] Shredded scrap rubber which is preferably salt water-tolerant is provided as a sound-absorbing material.

[0033] The pile 1 has supports 5 along its circumference, said supports being arranged about 4 to 6 m above the lower end thereof. The frame construction 60 has a base plate 68, by means of which the frame construction 60 rests on the supports 5. When the pile 1 is introduced using the frame construction 60, the pile 1 is submersed into the bottom, preferably to such an extent that the frame construction 60 is placed on the seabed 2 and the supports 5 or only on the seabed 2, wherein the sound protection sockets 91 and 92 dig into the seabed 2. The outer sound protection socket 91 has a length of e.g. approximately 1.50 m and the inner sound protection socket 92 has a length of approximately 1 m.

Therefore, the sound protection sockets 91 and 92 dig into the bottom about 1.5 and 1 m, respectively, and absorb the sound waves resulting in the seabed 2 during the driving operation. According to an embodiment of the invention, it is also possible to only one sound protection socket, e.g. the sound protection socket 91 or the sound protection socket 92. The sound protection sockets can also have a larger or smaller axial extension.

[0034] The pile 1 has typically a diameter of several meters and a wall thickness of several centimeters. A monopile has e.g. a diameter of about 4 m.

[0035] In the exemplary embodiment, the innermost socket 20 has a distance of about 300 mm from the pile 1 to be introduced into the seabed 2. The distance should be sufficient for the guide rollers 10 to have sufficient space. The guide rollers 10 are attached by means of a fork 13 to the innermost socket 20 in a way known to a person skilled in the art. The forks 13 are preferably made in springy fashion so as to compensate for possible irregularities of the pile 1. In the presentation as shown, guide rollers 10 are arranged at the upper and lower ends of the respective sections 60A, 60B and 60C, i.e. at the upper and lower ends of the individual sections of the sockets 20. Additional guide rollers 10 can be provided, if necessary. Alternatively, even fewer guide rollers 10 can be provided as long as sufficient guidance of the pile 1 to be introduced into the seabed 2 is ensured.

[0036] In the embodiment as shown, the socket 30 has a distance of about 200 mm from the inner socket 20. The socket 40 enclosing the socket 30 has a distance of about 100 mm from the socket 30. The outer socket 50 hat a distance of about 200 mm from the socket 40.

[0037] Of course, the dimensions or diameters of the sockets can also have other values. For example, the inner socket can have a distance of about 100 to 1000 mm, preferably of about 150 to 750 mm, more preferably of about 200 to 500 mm and in particular of about 250 to 400 mm. The distance between the socket 30 and the socket 20 can be about 50 to 500 mm, preferably about 100 to 400 mm and in particular 150 to 300 mm. The distance of socket 40 from socket 30 can be approximately 20 mm to 400 mm, preferably about 50 to about 300 mm and in particular about 75 to 150 mm. The distance of socket 50 from socket 40 can be about 20 mm to 400 mm, preferably about 50 to about 300 mm and in particular about 75 to 150 mm.

[0038] The pile 1 is preferably erected as follows. The sockets 20, 30, 40, 50 which, where appropriate, consist of several sections, are provided in a way where they are assembled as two half shells, i.e. the half shells 21,31,41 and 51 are joined by flanges and the other half shells 22, 32, 42 and 52 are also provided as an entire half shell. The pile 1 is placed in one half shell on the guide rollers 10. Then, the second half shell is attached via its flanges to the flanges of the first half shell. The frame construction 60 is already attached to the two half shells, and therefore the frame construction is also connected by the connection of the half shells. Where appropriate, it is possible to provide additional connecting means for connecting the frame construction parts.

[0039] The pile 1, including the sound protection device surrounding the pile 1, is subsequently erected by means of a crane and placed on the seabed.

Because of its weight, the pile 1 already sinks about 5 to 6 m into the seabed 2. The sound protection device is held with its base plate 68 by the supports 5 on which it rests. The outer and inner sound protection sockets 91 and 92 here sink into the seabed 2.

[0040] For driving the pile 1 into the seabed 2, a driving device is attached to the tip of the pile 1 and the pile 1 is driven into the bottom. The sound vibrations then occurring in the seabed 2 are absorbed by the sound protection sockets 92, 91. The sound protection device above the seabed 2 absorbs the vibrations occurring in the area of the water.

[0041] So-called monopiles can have an outer diameter of up to 6.5 m and a total weight of about 600 t. The sound protection device according to the invention can have a weight of up to 200 t and an outer diameter of 7.5 to 8 m for such monopiles.

[0042] In a preferred embodiment of the invention, the sound protection sockets 91 and 92 consist of two perforated metal plates which have a thickness of e.g. 1 to 3 cm and preferably of about 2 cm and between which a rubber layer having a thickness of 1 to 2 cm is introduced. Like the sockets 20, 30, 40, 50, the sound protection sockets 91,92 are made as half shells and can be connected by longitudinal flanges. According to an alternative embodiment, the connection of the half shells of the sound protection sockets 91,92 can be omitted because they penetrate the seabed and no solid connection is necessary when the connection of the sockets 20, 30, 40, 50 is sufficient.

[0043] According to the invention, the crane for introducing the pile into the seabed, as described above, can be equipped with the piles 1 as half shells which can be assembled on the crane. Alternatively, the piles to be introduced into the seabed can also be supplied in the sound protection device according to the invention in a complete fashion. The advantage is that the sound protection device has the dual function of a transport package for the pile 1. Furthermore, there is the advantage that fewer operators are required on the crane for assembling the half shells.

[0044] According to the invention, the costs might be reduced, in particular because the sound protection device can be reused since, after introducing the pile 1 into the seabed 2, the sound protection device can be pulled out of the sea and the seabed again by the crane.

[0045] According to the alternative embodiment of the invention, an air chamber can be provided in the sound protection device in place of the further bubble curtains. In the preferred embodiment of the invention, an air chamber can be provided e.g. in the socket 40. Due to the difficulty of sealing the sound protection device from the pile 1 at a water pressure of e.g. 4 bar, it is, however, preferred to provide a bubble curtain in the socket 20.

[0046] The guide rollers 10 can be used with a smaller outer diameter for adapting the sound protection device to the piles 1. For example, longer forks 13 can be provided. Alternately, the forks 13 can also be arranged with an inclination, and therefore the forks extend more in an axial direction of the sockets when the outer diameter of the pile 1 is larger and rather extend in the sectional plane, which is shown in figure 2, when the outer diameter of the piles 1 is smaller.

[0047] After the pile 1 or monopile was introduced into the bottom, a bottom protection plate is arranged around the pile 1 or monopile and e.g. a windmill of an offshore wind park is arranged on the monopile in known manner.

[0048] Of course, the invention is not limited to the embodiments shown in the figures. The above description should therefore not be regarded as limiting but as explanatory. The following claims should be comprehended in such a way that a feature mentioned is present in at least one embodiment of the invention. This does not rule out the presence of further features. If the claims and the above description define “first” and “second” features, this designation serves for distinguishing two similar features without determining an order.

Claims

1. Noise-canceling device for noise cancellation of pilot work for inserting piles (1) into the seabed (2) with a sleeve (20) surrounding the pile (1) to be introduced into the seabed and at least one additional sleeve is provided (30) surrounding the first sleeve (20), where noise-absorbing material (33) is inserted between the two sleeves (20), characterized in that between the first sleeve (20) and the pile (1), to be introduced into the seabed, a bubble veil (23) is formed, with air and air respectively. gas may be introduced through apertures (81) provided on a lower part (68) of a frame structure (60), and the noise-canceling material (33) contains or consists of fragmented rubber waste.

Device according to claim 1, wherein the sleeve is formed of at least two half bowls.

Device according to one of claims 1 or 2, characterized in that an additional sleeve (40) is provided which surrounds the sleeve (30) which accommodates the noise-dampening material and in which a bubble veil (43) can be guided.

Device according to one of claims 1 to 3, further comprising at least one noise damping sleeve (91.92) extending into the seabed (2).

Device according to one of claims 1 to 4, characterized in that the sleeve (20, 30) is composed in the axial direction of several elements (60A, 60B, 60C).

Device according to one of claims 1 to 5, characterized in that guide rollers (10) for guiding the pile (1) to be introduced into the seabed are provided within the sleeve (20).

Device according to claim 6, characterized in that several layers of guide rollers are located along the axial direction of the device.

Apparatus according to one of claims 6 or 7, wherein the guide rollers exhibit a vibration-damping coating, preferably a rubber coating.

Device according to one of claims 1 to 7, wherein a frame structure (60) is arranged around the outer sleeve (50).

Device according to one of claims 1 to 9, characterized in that there is an additional sleeve (50) surrounding the sleeve (40) receiving the bubble tube (43), where between the sleeve (40) surrounding the bubble tube ( 43) and the additional sleeve (50) is disposed of a noise canceling material (53).

Device according to any one of claims 1 to 10, wherein the sleeves (20, 30, 40, 50) are formed as semi-bowls, which are preferably separated from each other by separating surfaces.

Device according to one of claims 1 to 11, wherein extensions for acoustic separation are provided on the separating surfaces.

A method of inserting piles into the seabed, wherein the pile (1) to be inserted is surrounded by a first sleeve (20) and there is an additional sleeve (30) located around the first sleeve (20) and absorbs noise-canceling material, characterized in that a bubble veil (23) is formed between the first sleeve (20) and the pile (1) to be driven into the bottom, and the noise-canceling material (33) contains or consists of fragmented rubber waste.

The method of claim 13, wherein a noise attenuation sleeve (91.92) is inserted into the seabed.

Method according to one of Claims 13 or 14, characterized in that the pile is driven by guiding rollers located between the sleeve and the pile upon recovery.