Vibration device, method for inserting or removing a foundation element into / from the ground, and assembly with foundation element

Abstract

The application relates to vibration device (2) for inserting a foundation element (4) into the ground, an assembly of a vibration device with foundation element, methods for inserting and removal of a foundation element (4) and such foundation element (4), wherein the vibration device comprises: • - a frame (8) with a clamping mechanism that is configured to clamp the foundation element (2); • - at least one vibration element (12) that is operatively connected to the frame (8); • - a vibration chamber (14,18) that is provided in or attached to the frame (8) for housing the at least one vibration element (12); • - at least one drive (24,26) that is operatively connected to the at least one vibration element (12), wherein the at least one vibration element (12) is configured for performing a rotational movement in the vibration chamber (14,18) around a longitudinal axis of the foundation element (4) for generating torsional vibrations.

Description

[0001] VIBRATION DEVICE, METHOD FOR INSERTING OR REMOVING A FOUNDATION ELEMENT INTO / FROM THE GROUND, AND ASSEMBLY WITH FOUNDATION ELEMENT

[0002] The invention relates to a vibration device and method(s) for inserting / removing a foundation element into / from the ground, including a seabed. The vibration device and method(s) can be used for both land-based and sea-based foundation elements. The invention also relates to an assembly comprising such vibration device and foundation element.

[0003] Vibration devices for placing or inserting foundation elements, such as foundation piles, into the ground are known. For example, such devices are used in the placement of foundations for wind turbines. The known vibration devices drive the foundation element, such as a solid or hollow foundation pile, into the ground using axial vibrations. To that end, the known vibration devices comprise at least one vibration block that is connected to the upper side of the foundation pile.

[0004] WO 2023 / 091010 Al discloses a vibration device that can advantageously be used to include torsional vibrations to insert the foundation element. Especially the use of torsional vibration reduces the amount of noise emitted during insertion of the foundation element.

[0005] Although a combination of torsional and axial vibrations provides some noise reduction, there remains a need to further reduce noise emissions when inserting a foundation element into the ground, including a seabed.

[0006] An object of the present invention is to obviate or reduce one or more of the above- mentioned problems.

[0007] This object is achieved with the vibration device according to the invention for inserting a foundation element into the ground with torsional vibrations, the device comprising:

[0008] - a frame with a clamping mechanism that is configured to clamp the foundation element;

[0009] - at least one vibration element that is operatively connected to the frame;

[0010] - a vibration chamber that is provided in or attached to the frame for housing the at least one vibration element;

[0011] - at least one drive that is operatively connected to the at least one vibration element, wherein the at least one vibration element is configured for performing a rotational movement in the vibration chamber around a longitudinal axis of the foundation element for generating torsional vibrations.

[0012] By providing a clamping mechanism the vibration device can be operatively connected to the foundation element. Several conventional clamping mechanisms may be applied, such as the clamping mechanism described in W0 2022 / 060225 A2 of the same applicant. The vibration element can be clamped with the clamping device in, on and / or around the upper side of the foundation element and / or at any other suitable position of the foundation element.

[0013] The vibration element moves in the vibration chamber over at least part of the length of the vibration chamber. The vibration element or elements may have significant weights, for example 200 tons. Such weight of the vibration element enables generating of significant and effective torsional vibrations that assist in driving the foundation element into the ground.

[0014] By providing a rotational movement of the at least one vibrational element around the longitudinal axis of the foundation element, preferably along the circumference of the foundation element, a torsional vibration can be generated. The rotational movement can be over a part of a circle, such as a part of the circumference of the foundation element, or over a complete circular path. This results in torsional forces acting upon the foundation element.

[0015] In combination with its weight the foundation element will be inserted into the ground, optionally in a land-based or sea-based situation. A frequency of the rotational movement and a displacement distance or amplitude of this rotational movement is set manually by a user / operator or automatically by a controller. Optionally, frequency and / or displacement amplitude can be adjusted in view of the circumstances and / or prosecution of the inserting process. Such adjustment can be made manually by a user / operator or automatically by a controller.

[0016] The application of torsional vibrations generated by the at least one vibration element moving in a vibration chamber in a plane that is substantially perpendicular to the longitudinal axis of the foundation element significantly reduces noise emissions in the inserting process. It is believed that this is caused by the reduction of radial expansion of the foundation element. It was shown that such reduction is also achieved in an underwater environment when placing the foundation element in a seabed. Optionally, more than one vibration element can be applied, such as two, three, four or any other suitable number of vibration elements.

[0017] A further advantage of the vibration device according to the present invention is that it is possible to generate a one directional force that is then supplied to the foundation element. Together with the use of torsional vibrations this obviates the need for a separate suppressor unit to dampen axial vibrations being transferred to the crane or other hoisting means. This significantly reduces the risk of damaging the external equipment.

[0018] Furthermore, fatigue of the foundation element during the inserting process is significantly reduced. This improves the lifetime of the foundation element.

[0019] In a presently preferred embodiment of the invention the vibration device can be set in different modes by varying the frequency and displacement distance of the vibration element. This provides an efficient vibration device that can be relatively easily adapted to the specific circumstances of the inserting process, including specifications of the (expected) relevant ground layers. Optionally, it is possible to switch between different modes at the beginning and / or during the inserting process. Next, some examples of different modes will be briefly described.

[0020] In a first mode, high frequency torsional vibrations in a frequency range of 30 to 60 Hz are applied, preferably with a relatively low displacement amplitude in the range of 1 to 3 mm. This mode has as one of its objectives to reduce the resistance against moving of the foundation element itself into the ground. In addition, to some extent, in this mode also the resistance encountered at the base or end of the foundation element can be reduced.

[0021] In a second mode, low frequency torsional vibrations in the range of 5 to 20 Hz are applied with a relatively large displacement amplitude in the range of 3 to 20 mm. In this second mode, as compared to the first mode, the foundation element is inserted over a larger distance and / or faster into the ground, especially in more solid ground layers having a higher resistance.

[0022] In a third mode, torsion pulses are generated, preferably in alternating directions, preferably in a frequency range of 1 to 5 Hz, preferably with a relatively large amplitude of 3 to 50 mm. These pulses are specifically applied when being confronted with a relatively high resistance ground layer. Optionally, this third mode can be applied in combination with the first and / or second mode(s).

[0023] Optionally, a user switches between different modes depending on the actual ground layers during the inserting process of the foundation element.

[0024] In atypical inserting process, the inserting process starts in mode 1. When being confronted with a high(er) resistance of the ground layer, a switch can be made to mode 2, or optionally mode 2 is applied in combination with mode 1. In case one encounters an even higher resistance of the ground layer, torsional pulses can be applied according to mode 3, optionally in combination with mode 1 and / or mode 2.

[0025] When using a vibration device in an embodiment according to the present invention, a user may set the actual mode and / or frequencies and amplitudes through an interface to the controller of the vibration device. Optionally, if needed, the user may adjust the settings depending on the development of the inserting process. This adjustment can be done manually or automatically, for example by measuring the progress and / or resistance during the inserting process and correspondingly adjusting the frequency and / or amplitudes, for example.

[0026] In one of the present embodiments of the invention a 5 MW power supply is provided to the vibration device for moving the vibration element in the vibration chamber. It will be understood that the power supply is adapted to the configuration of the vibration device in view of the number of vibration elements, the weight of the vibration elements and / or other relevant parameters.

[0027] In a presently preferred embodiment of the invention the vibration chamber is ring-shaped. Providing a ring-shaped vibration chamber enables the at least one vibration element to move in the vibration chamber in a controlled manner, preferably over the entire length of the vibration chamber. This movement enables generating a controlled torsional vibration with the at least one vibration element. In such embodiment the vibration element moves in the vibration chamber in a circumferential direction of the foundation element in a plane that is substantially perpendicular to the longitudinal axis of the foundation element. The movement of the vibration element can be along a part of the circumference of the foundation element. Preferably, in a presently preferred embodiment of the invention, the vibration chamber is circular and extends over the entire circumference of the foundation element and substantially surrounds this circumference of the foundation element. This enables movement of the vibration element over the entire circumference of the foundation element, thereby providing a maximum of flexibility for generating torsional vibrations.

[0028] Preferably, at least one of the at least one vibration elements is ring-shaped. This ringshaped vibration element, or vibration elements, is / are preferably shaped to enable an effective movement in the vibration chamber, wherein the vibration chamber is also preferably ring-shaped. By providing a ring-shaped vibration element the vibration device can be used in an (inserting) operation in an effective manner. Rotating the ring-shaped vibration element generates a torsional vibration. By accelerating or deaccelerating / stopping movement of the vibration element a pulse is generated in accordance with mode 3 that was described earlier.

[0029] The ring-shaped vibration element is preferably combined with the ring-shaped vibration chamber. One of the advantages of such ring-shaped combination is the maximum surface area for positioning a drive, more preferably an electromagnetic drive. Furthermore, the generated forces are provided close to the foundation element. The ring-shaped combination also enables an effective clamping of the foundation element. Furthermore, this specific ring-shape enables providing a relatively high torsion pulse with a relatively small mass, thereby providing an effective device for operating in mode 3, as explained earlier. A further advantage is that the ringshape enables providing an opening, as will be described later, with the advantage of fluidizing or removing material in / from the inside of the foundation element.

[0030] Movement of the vibration element can be achieved in several ways, including providing an electromagnetic drive or a hydraulic drive or any other suitable device, or any combination thereof.

[0031] In a presently preferred embodiment at least one electromagnetic drive is provided. Such drive enables an electric power supply, thereby contributing to a further reduction in emissions when using the vibration device according to the invention. Furthermore, using an electromagnetic drive also enables regeneration of energy, for example when deaccelerating or stopping the vibration element when it is moving in the vibration chamber. This enables an effective way when operating in mode 3, for example. Using such energy regeneration, generating pulses can be done energy efficiently. In one of the preferred embodiments the one or more of the vibration elements are provided with electromagnets or permanent magnets that enable movement in a housing or wall of the vibration chamber that is provided with stationary circuits or coils that can be controlled by the controller of the vibration device. Optionally, electromagnets or permanent magnets can also be provided in the stationary housing of wall while the circuits or coils are provided in the vibration element.

[0032] In case of applying a hydraulic drive the vibration element is preferably moved over a part of the circumference of the foundation element and then engages a stopping member such as a wall, edge, pen or other suitable stopping means. This generates a pulse as described in relation to mode 3. However, an advantage of the aforementioned application of an electromagnetic drive is a possibility for energy regeneration.

[0033] A further preferred embodiment the frame of the vibration device further comprises a bearing that is operatively connected to the at least one vibration element.

[0034] The bearing enables a relative movement between the vibration element and the foundation element and / or vibration chamber of the frame. This bearing may involve application of air bearing, roll bearing, a presently preferred electromagnetic bearing to minimize resistance against movement of the vibration element in the vibration chamber, or other suitable bearing.

[0035] In a further preferred embodiment of the invention, the vibration device further comprises an energy regeneration system.

[0036] Such regeneration system can be provided in different configurations. In one of the presently preferred embodiments the regeneration device is used in combination with an electromagnetic drive such that energy can be regenerated when deaccelerating or stopping the vibration element when moving in the vibration chamber. This provides an energy efficient vibration device.

[0037] In a further preferred embodiment of the invention the vibration device further comprises a number of excentre weights.

[0038] A combination of excentre weights can be used for axial and / or torsional vibrations as described in the aforementioned application WO 2023 / 091010 Al of the same applicant. However, according to the present invention the excentre weights are (mainly) used for the axial vibrations and can optionally be used to enhance the torsional vibrations that are preferably generated with the vibration element that moves in the vibration chamber. This enables combination of axial and torsional vibrations in an effective manner. Especially the use of the vibration element with the vibration chamber according to the present invention enables providing a torsional pulse to the foundation element. This enables inserting the foundation element in the ground also in difficult circumstances with high resistance ground layers. It is noted that in one of the possible embodiments of the invention the excentre weights are moved with a hydraulic drive while the vibration element is moved in the vibration chamber with an electromagnetic drive. Alternatively, all weights and vibration elements are driven electromagnetically or hydraulically.

[0039] In a further preferred embodiment of the present invention the frame of the vibration device comprises an opening that extends in a plane that is substantially perpendicular to the axial direction of the frame.

[0040] By providing the opening it is possible to have access to the inside of the foundation element in a mounted state of the vibration device. This is especially relevant when inserting a tube-like foundation element into the ground. In such case, it is possible to remove ground or soil or other material from the inside of the foundation element when inserting the foundation element into the ground. This reduces the resistance in the inserting process. In addition, or as an alternative, the opening can also be used to fluidize the internal material and / or bottom of the ground layer that is engaged by the foundation element. Also, in this situation the resistance in the inserting process is significantly reduced. This enables a more effective and energy-efficient inserting process.

[0041] The invention further relates to an assembly of a vibration device according to an embodiment of the present invention and a foundation element.

[0042] The assembly according to the invention provides similar effects and advantages as described in relation to the vibration device. It is further noted that the foundation element preferably comprises a circular cross-section as seen in a plane perpendicular to the longitudinal axis of the foundation element, such as a tube or pipe, or any other tube-like foundation element.

[0043] In a preferred embodiment the foundation element comprises a profiled base. This profiled base relates to the lower end of the foundation element during the inserting process. By providing a profiled base it was shown that the inserting process was more efficient, especially when dealing with ground layers having a relatively high resistance. The choice for a specific profile for this profiled base may depend on the type of ground layers and the available power, optionally in combination with the rigidity of the foundation element itself.

[0044] It is furthermore noted that the profiled base may preferably comprise a toothed profile. In such profile the height can be adapted to the specific circumstances that are expected. For example, a higher profile, which means a larger difference in height of the profile as seen in the longitudinal direction of the foundation element, generates more resistance in the inserting process. This may result in a higher speed of the inserting process. A relatively low or limited profile height of the profiled base reduces the inserting speed of the inserting process as less ground or soil or other material is being replaced at the base of the foundation element. At the same time, the resistance reduces and such profile is specifically beneficial when inserting a foundation element in ground layers having a relatively high resistance and / or when it is desirable to reduce the dimensions and power requirements of the vibration device.

[0045] Alternatively, a wave pattern or sinusoid pattern or any suitable pattern can also be provided for the profde base.

[0046] The invention further also relates to a method for inserting a foundation element into the ground with torsional vibrations, the method comprising the steps of:

[0047] - providing a vibration device according to an embodiment of the present invention;

[0048] - clamping the foundation element with the clamping mechanism;

[0049] - driving the at least one vibration element with the drive and generating torsional vibrations; and

[0050] - driving the foundation element into the ground.

[0051] The method provides the same or similar effects and advantages as described in relation to the vibration device and / or assembly.

[0052] The method according to the invention provides an effective and efficient inserting process for inserting a foundation element into the ground with torsional vibrations. Preferably, in the inserting process one or more of the aforementioned modes can be selected. Optionally, switching between modes and combination of modes is also possible. This enables performing the method in combination with the most effective mode or modes.

[0053] In a presently preferred embodiment of the invention the method further comprises the step of generating a torsional vibration with a frequency in the range of 0. 1 Hz to 200 Hz, preferably in the range of 0.5 Hz to 100 Hz, more preferably in the range of 1 Hz to 80 Hz, and most preferably in the range of 1 Hz to 60 Hz. It was shown that the application of such frequencies or any combination of different frequencies in this range or ranges provided good results when inserting a foundation element into the ground.

[0054] In a further preferred embodiment according to the invention, the method further comprises the step of generating a torsional vibration with a displacement amplitude in the range of 0.1 mm to 100 mm, preferably in the range of 0.5 mm to 75 mm, more preferably in the range of 1 mm to 60 mm, and most preferably in the range of 1 mm to 50 mm.

[0055] Especially the combination of applying a frequency and displacement amplitude in the mentioned ranges provide good results. Even further, a combination of frequencies and amplitudes as mentioned in relation to the different modes that were mentioned earlier provides preferred combinations that can be effectively used.

[0056] In presently preferred embodiments of the invention several so-called drive modes have been defined. In a first mode high frequent vibrations in the range of 30 Hz to 60 Hz are applied in combination with relatively low (displacement) amplitude in the range of 1 mm to 3 mm. This reduces or minimizes the resistance against moving of the foundation element itself into the ground (shaft resistance) and reducing the resistance at the lower end of the foundation element. In a second mode low frequent vibrations in the range of 5 Hz to 30 Hz are applied in combination with relatively high (displacement) amplitude in the range of 3 mm to 20 mm. This mode enables driving the foundation element faster and / or farther into the ground. This second mode is especially effective when confronted with a ground having higher resistance(s). In a third mode pulses / punches are provided in the torsional direction with frequencies in the range of 1 Hz to 5 Hz in combination with relatively large (displacement) amplitude in the range of 3 mm to 50 mm. This third mode is especially effective when confronted with a ground having (very) high resistance(s). Additionally, this third mode can be used to change the orientation of the foundation element, for example by providing pulses / punches in the same direction. It will be understood that other modes and / or combinations of modes can also be envisaged in accordance with the present invention.

[0057] In a further preferred embodiment of the invention the method comprises the step of adjusting the frequency, displacement amplitude and / or power. This adjusting can be done manually and / or automatically. For example, when starting the inserting process, the settings can be selected in accordance with mode 1, and when engaging a ground layer having a high resistance a switch can be made to settings according to mode 2. In case an even higher resistance is engaged, a torsion pulse according to mode 3 can be used as an alternative or in combination with one of the other modes.

[0058] In a further embodiment of the invention the method further comprises the step of removing ground or other material in the foundation element. Alternatively, or in addition thereto, the method may comprise the step of fluidizing the ground or other material in the foundation element. Both these method steps can be used separately or in combination to reduce the resistance and improve the inserting process.

[0059] In a further preferred embodiment of the invention the method comprises the step of designing the profile base of the foundation element.

[0060] Preferably, the profiled base of the foundation element is designed as function of the type of ground and material thereof, and preferably in combination with the available power. Optionally, in the design process also the rigidity of the foundation element can be taken into account.

[0061] In presently preferred embodiments of the invention, the vibration device can also be used for lifting / hoisting and / or upending the foundation element.

[0062] In a further preferred embodiment of the invention the method further comprises the step of upending the foundation element before starting the actual inserting process.

[0063] The invention further also relates to a method for moving a foundation element from the ground with torsional vibrations, the method comprising the steps of:

[0064] - providing a vibration device embodiment according to the present invention; - clamping the foundation element with the clamping mechanism;

[0065] - driving the at least one vibration element with the drive and generating torsional vibrations; and

[0066] - removing the foundation element from the ground.

[0067] The method for removing the foundation element from the ground with torsional vibration provide the same or similar effects as described in relation to the vibration device, assembly and / or method for inserting a foundation element. It is noted that removing a foundation element from the ground is also referred to as decommissioning a foundation element. This method may include all steps and features as described earlier in relation to the vibration device, assembly and method for inserting a foundation element.

[0068] The invention further also relates to a foundation element, wherein the foundation element comprises a profded base.

[0069] Such foundation element provides the same or similar effects as described in relation to the vibration device, assembly, and associated methods. The profiled base specifically relates to the lower end of the foundation element in the inserting process. Preferably, the profiled base comprises a toothed profile.

[0070] Further advantages, features and details of the invention are elucidated on the basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which:

[0071] - Figures 1 A-C shows an embodiment of the vibration device according to the present invention;

[0072] - Figures 2A-B shows an alternative embodiment of the vibration device according to the present invention;

[0073] - Figures 3A-D shows the pending of the vibration device as shown in figure 2A-B;

[0074] - Figures 4 A-D shows embodiments of the lower ends of the foundation element; and

[0075] - Figure 5 shows a schematic overview of (some of) the relevant process steps.

[0076] Vibration device 2 (figure 1A-C) is positioned at upper end 4a of foundation element 4. The combination of vibration device 2 and foundation element 4 is referred to as assembly 6. In the illustrated embodiment vibration device 2 comprises frame 8 that is positioned over top end 4a of foundation element 4 and is positioned with clamping elements 10 (schematically illustrated in figure IB).

[0077] In the illustrated embodiment two ring-shaped vibration elements 12 are provided in vibration chamber 14 and extend over the entire circumference 16 of foundation element 4. In this illustrated embodiment frame 8 comprises housing 18 that extends also over the entire circumference of the foundation element 4 and is provided with a top opening 20 allowing access to the inside 22 of foundation element 4. In this illustrated embodiment housing 18 comprises vibration chamber 14. The vibration elements 12 may move independently from each other in direction D. This movement of foundation elements 12 in vibration chamber or chambers 14 results in foundation element 4 moving in direction A when inserting foundation element 4 into the ground.

[0078] Vibration elements 12 are provided with a number of electromagnets or permanent magnets 24 and vibration chamber 14 / housing 18 is provided with a (large) number of circuits or coils 26 that are activated or deactivated or otherwise controlled by controller 28 (schematically illustrated in figure IB). Pump device 30, or another suitable device, removes ground and / or other material from inner space 22 of foundation element 4 in direction B and / or provides liquid in a direction C to the inner space 22 of foundation element 4 to fluidize the material in foundation element 4 and / or ground layer. Optionally, controller 28 provided with user interface 32 that enables a user to provide settings or adjustments to controller 28. In this illustrated embodiment, the electromagnetic drive of vibration device 2 comprises magnets 24 of vibration elements 12 and circuits or coils 26. Also in this illustrated embodiment, power is supplied to circuits or coils 26 by supplies 34 from power supply 36 that is also schematically illustrated in figure IB.

[0079] In an alternative embodiment vibration device 52 is provided to foundation element 54, together forming assembly 56 (figures 2A-B). In this illustrated embodiment vibration device 52 is provided as a ring having hinge 58 to allow vibration device 52 to open and to be positioned around foundation element 54. Hoisting elements 60 of vibration device 52 are connected to hoisting cables 62. After positioning vibration device 52, device 52 it is closed and secured. In this illustrated embodiment vibration device 52 is positioned along the length of foundation element 54. Connection element 64 secures ring-shaped vibration device 52 in a closed position. Foundation element 54 is provided with side surface 66 having inner space 68.

[0080] In the illustrated embodiment vibration elements 52 (figures 2A-B) comprises three substantially circumferential grooves 78 that are positioned above each other in the longitudinal direction L of axis X of foundation element 54. In this illustrated embodiment, vibration device 52 is provided with lower ring of excentre weights 70 and an upper ring of excentre weights 72. In the illustrated embodiment middle or center ring is provided with vibration chamber 74, wherein at least one vibration element 76 is provided. The number of vibration elements 80 are provided with a number of drives 82. In this illustrated embodiment, vibration elements 80 comprise excentre weights 70,72. Ring shaped vibration element 52 has height H and width W. Vibrational element 76 is moved in vibration chamber 84 with circuits or coils 86. In this illustrated embodiment vibration element 76 is provided with permanent or electromagnets 24. Vibration element 76 moves in direction D, while excentres 70, 72, 80 may rotate in direction T.

[0081] It will be understood that a different number of rows can be provided and that these rows can also be positioned differently. Optionally, no excentres 70, 72, 80 are provided and only a vibration element 76 is provided. Optionally, also in this embodiment pump device 30, controller 28 and interface 32 can be provided.

[0082] It will be understood that the embodiments of vibration device 2, 52 can also be positioned in a different location depending on the specific configuration of the clamping elements and / or other suitable elements.

[0083] In the illustrated embodiments of vibration device 2, 52, vibration element 12, 76 is ringshaped in conformity with the ring-shaped vibration chamber 14, 84. In the illustrated embodiments vibration device 2, 52 is provided with supply lines 34 that are operatively connected to power supply 36. In addition, optionally, excentres 70, 72, 80 are provided with one or more drives 82 that is / are powered via supply lines 88 from power supply 90. Power supplies 36, 90 can be electric or hydraulic, for example. Optionally, power supplies 36, 90 can be combined into one integrated power supply.

[0084] Bearing 92 is schematically illustrated in figure 2B and is preferably an electromagnetic bearing.

[0085] Supply lines 34, 88 are preferably two-directional to enable regenerating of energy when accelerating or stopping movement of vibration element 12, 76. The regeneration system is formed by energy supply 36, 90, and supply lines 34, 88 that transfer energy that is generated by circuits or coils 26 as a result of movement of vibration element 12, 76.

[0086] Ship or vessel 252 (figures 3 A-D) is used in the process of upending foundation element 4, 54. Upending is performed using crane 254. Foundation element 4, 54 is slowly put in a vertical position, which is called upending, while being suspended on hoisting cables 62. During the upending process, foundation element 4, 54 is slowly moved from a substantial horizontal position to a substantially vertical position in which foundation element 4, 54 can be inserted into ground G. In this illustrated embodiment vibration device 2, 52 remains clamped onto foundation element 4, 54. It will be understood that another clamping position of vibration device 2, 52 can also be envisaged in accordance with the present invention. In this illustrated embodiment the upending is done with vibration device 2, 52 already positioned on foundation element 4, 54. Alternatively, vibration device 2, 52 is positioned relative to foundation element 4, 54 after being positioned in a substantially upright / vertical position.

[0087] Profiled base 102 (figures 4A-D) is also referred to as base end and is optionally provided with a profile (figures 4B - D) having different shapes. For example, profile 104 (figure 4B) has a wave shape. Profiles 6 (figure 4C) and 108 (figure 4D) are toothed and have a number of teeth, wherein the teeth are optionally slightly round. Profiles 108, 106 differ with respect to height h of the profile, thereby defining the resistance against movement in an additional direction of foundation element 4, 54. When inserting foundation element 4, 54 into the ground, in one of the presently preferred embodiments of the invention, inserting process 150 (figure 5) is started with design step 152 to design profile 104, 106, 108 using information about ground G and power supplies 36, 90. Then, clamping process 154 is used to position vibration device 2, 52 at or on foundation element 4, 54 after which it is possible to start upending step 156 and / or a hoisting step. It will be understood that the upending step 156 is optional and depends on the orientation of foundation element 4, 54. Also, steps can be changed in order. After positioning step 158 assembly 6, 56 is correctly positioned and inserting process 160 can be started by providing power to vibration device 2, 52 and inserting foundation element 4, 54 into ground G. Optionally, settings that are provided to controller 28 can be set and / or adjusted in adjusting step 162. This may include switching between different modes, of which examples were described earlier. This may optionally involve combinations of different modes. In one of the presently preferred embodiments of the invention ring-shaped vibration element(s) is / are used to provide high frequent, low frequent and / or torsional pulse s / punches. In addition, ground or other material can be removed in removal step 164 from foundation element 4, 54 and / or liquid can be provided to fluidize ground G.

[0088] Decommissioning process 170 may start with providing vibration device 2, 52 to foundation element 4, 54 in preparation step 172. Removing or decommissioning is then performed in removal step 174. In process 170 an adjusting or switching step 176 can be performed. Finally, after removing foundation element 4, 54 from ground G, foundation element 4, 54 can be removed in removal or transport step 178.

[0089] Experiments with different embodiments of the present invention involving torsional vibrations have shown a significant reduction in noise emissions during the inserting and / or decommissioning step(s). Especially the application of vibration elements having a ring-shape in combination with a ring-shaped vibration chamber has shown a further significant improvement in the noise reduction. Especially the application of an electromagnetic drive turned out to provide an energy efficient process involving regeneration system.

[0090] The present invention is by no means limited to the above described preferred embodiments and / or experiments thereof. The rights sought are defined by the following claims within the scope of which many modifications can be envisaged.

Claims

CLAIMS1. Vibration device for inserting a foundation element into the ground with torsional vibrations, the device comprising:- a frame with a clamping mechanism that is configured to clamp the foundation element;- at least one vibration element that is operatively connected to the frame;- a vibration chamber that is provided in or attached to the frame for housing the at least one vibration element;- at least one drive that is operatively connected to the at least one vibration element, wherein the at least one vibration element is configured for performing a rotational movement in the vibration chamber around a longitudinal axis of the foundation element for generating torsional vibrations.

2. Vibration device according to the foregoing claim, wherein the vibration chamber is ringshaped.

3. Vibration device according to the foregoing claim, wherein the vibration chamber substantially surrounds the circumference of the foundation element.

4. Vibration device according to any of the foregoing claims, wherein the vibration element is ring-shaped.

5. Vibration device according to any of the foregoing claims, wherein the drive comprises an electromagnetic drive.

6. Vibration device according to any of the foregoing claims, wherein the frame further comprises a bearing that is operatively connected to the at least one vibration element.

7. Vibration device according to the foregoing claim, wherein the bearing comprises an electromagnetic bearing.

8. Vibration device according to any of the foregoing claims, further comprising an energy regeneration system.

9. Vibration device according to any of the foregoing claims, further comprising a number of excentre weights.

10. Vibration device according to any of the foregoing claims, wherein the frame comprises an opening that extends in a plane that is substantially perpendicular to the axial direction of the frame.

11. Assembly of a vibration device according to any of the foregoing claims and a foundation element.

12. Assembly according to the foregoing claim, wherein the foundation element comprises a profded base.

13. Assembly according to the foregoing claim, wherein the profiled base comprises a toothed profile.

14. Method for inserting a foundation element into the ground with torsional vibrations, the method comprising the steps of:- providing a vibration device according to any of the foregoing claims 1 - 10;- clamping the foundation element with the clamping mechanism;- driving the at least one vibration element with the drive and generating torsional vibrations; and- driving the foundation element into the ground.

15. Method according to the foregoing claim, further comprising the step of generating a torsional vibration with a frequency in the range of 0. 1 Hz to 200 Hz, preferably in the range of 0.5 Hz to 100 Hz, more preferably in the range of 1 Hz to 80 Hz, and most preferably in the range of 1 Hz to 60 Hz.

16. Method according to any of the foregoing claims 14 - 15, further comprising the step of generating a torsional vibration with a displacement amplitude in the range of 0. 1 mm to 100 mm, preferably in the range of 0.5 mm to 75 mm, more preferably in the range of 1 mm to 60 mm, and most preferably in the range of 1 mm to 50 mm.

17. Method according to any of the foregoing claims 14 -16, further comprising the step of adjusting the frequency, displacement amplitude and / or power.

18. Method according to any of the foregoing claims 14 - 17, further comprising the step of removing ground in the foundation element.

19. Method according to any of the foregoing claims 14 - 18, further comprising the step of fluidizing ground in the foundation element.

20. Method according to any of the foregoing claims 14 - 19, further comprising the step of designing the profiled base of the foundation element.

21. Method according to any of the foregoing claims 14 - 20, further comprising the step of upending the foundation element.

22. Method for removing a foundation element from the ground with torsional vibrations, the method comprising the steps of:- providing a vibration device according to any of the foregoing claims 1 - 10;- clamping the foundation element with the clamping mechanism;- driving the at least one vibration element with the drive and generating torsional vibrations; and- removing the foundation element from the ground.

23. Foundation element, wherein the foundation element comprises a profiled base.

24. Foundation element according to the foregoing claim, wherein the profiled base comprises a toothed profile.

Images