Vibrating device and method for inserting a foundation element into the ground

VIBRATION DEVICE AND METHOD FOR PLACING

A FOUNDATION ELEMENT

The invention relates to a vibrating device for introducing a foundation element, such as a foundation pole for a windmill, into a substrate. Such foundation elements can hereby be brought into a subsurface on land as well as at sea.

Vibrators are known from practice for placing a foundation pile on which a structure such as a windmill can be mounted. Such vibrating devices make use of the vibration of a solid or tubular pile, wherein this pile is vibrated into the ground with a vibrating block. Such blocks are often connected in a substantially vertical position of the foundation pile to the top side of the foundation pile. Good coordination between the dimensions of the foundation pile and the relevant block is required. In practice, this is often time-consuming, with a relatively poor view of the coupling due to the large distance, with a relatively high risk of inaccuracies with an increased risk of accidents.

It is also known from practice to arrange a vibrating block on a foundation pile while it is provided in a horizontal position. In this case, large forces are required for bringing the foundation pile with the vibrating device from the horizontal position to the vertical vibrating position. The various components of the vibratory block are hereby subjected to these large forces during rotation, often at an unfavorable angle, so that the lifespan of the vibratory block is limited and / or additional maintenance is required. In such conventional devices, components such as spring elements of the vibrating device are subjected to changing deflection, which makes it difficult to obtain a correct angle of rotation and thereby connect the vibrating device to the foundation pile. In addition, spring elements, in particular spring elements which make use of elastomers, appear to exhibit relatively much spread in strength in practice, so that after a period of time, particularly with large loads occurring, breakage can occur. This increases the risk of accidents during the positioning of the foundation element.

An object of the present invention is to eliminate or alleviate the above problems and to provide an effective vibrating device for bringing a foundation element into a substrate.

This object is achieved with the aid of the vibrating device for placing a foundation element according to the present invention into a substrate, wherein the vibrating device comprises: a clamping mechanism for clamping the foundation element; a vibrating block configured to provide a vibration for bringing the foundation element into the substrate, the vibrating block being provided with spring elements; and a fixation mechanism configured to bias the spring elements such that movement of the spring elements is reduced.

By applying a bias with the fixing mechanism to the spring elements that are present in the vibrating device, relative movements between parts of the vibrating device during positioning thereof are prevented and preferably completely avoided. The fixation mechanism makes it possible, as it were, to temporarily isolate the spring elements from the force game. The spring elements are formed by, for example, springs, rubbers, elastomers, or other resilient elements. These spring elements serve not to transmit forces that are exerted on the foundation element during the vibrating process to the rest of the installation.

During positioning of the foundation element with the vibrating device, wherein, for example, a rotation is carried out with the rotation mechanism such that the foundation element is hoisted and erected with the vibrating device, it appears in practice that a relatively large movement occurs due to the forces occurring during the vibrating device. positioning. For example, an offshore foundation element weighs approximately 1800 tons and has a diameter of, for example, approximately 6 meters. This results in large forces exerted on the device. The relative movements during positioning, in particular, result in wear on components, in particular the spring elements, as a result of which the lifespan of the vibrating device is significantly limited. This also leads to practical problems with regard to, for example, the usability of vibrating devices if, for example, several foundation elements have to be placed offshore with one and the same vibrating device.

The forces that occur during the positioning of the foundation element with the vibrating device are particularly large in case a vibrating device is applied to a foundation element that is still in a non-vertical position, i.e. has not yet been brought into a vibrating position. This means that the assembly of vibrating device and foundation element must still be rotated to a substantially vertical vibrating position before use. Such a movement is also referred to as "up-enden". In this case, in practice with conventional systems, damage occurs in particular to the spring elements due to the relative movement that parts of the vibrating device perform relative to each other. By using the fixing mechanism with which the spring elements are biased, this damage is reduced or even avoided altogether, so that the service life of the vibrator according to the invention is significantly extended.

The foundation element can be provided in various forms, including a pole, tube, pipe and the like. In particular, the foundation element also comprises a tubular foundation pile provided with a flange on which a construction, such as a windmill, can be placed.

The fixation mechanism preferably comprises a number of cylinders for applying a bias to the spring elements. The number is, for example, one, two or four cylinders. It will be clear that a different number of cylinders can also be used. By controlling the cylinders, for example, it is achieved that the spring elements are isolated from the force play for the hoisting process. This total or at least partial blocking of the spring elements ensures that virtually no relative movement occurs between parts of the vibrating device during the positioning of the vibrating device, in particular during the so-called "up-lifting" of the assembly of vibrating device with foundation element.

In an advantageous preferred embodiment according to the present invention, the vibrating device comprises a rotation mechanism which is operatively connected to the vibrating block and configured for rotating the vibrating block with the spring elements, the clamping mechanism holding the foundation element.

By providing a rotation mechanism, it is possible to carry out the above-described "up-endening". The combination of rotation mechanism with clamping mechanism and spring elements ensures that undesired damage to components as a result of the forces occurring is prevented and preferably even completely avoided. It appears that due to the combination mentioned, the usability of the vibrator improves significantly in practice.

In an advantageous preferred embodiment according to the present invention, the rotation mechanism comprises a cylinder.

By providing the rotation mechanism with a cylinder, a rotation for the benefit of, for example, the so-called 'up-endening' can be carried out effectively. The rotation movement does not require the use of a winch and / or hoisting installation. This increases the ease of use of the vibration device according to the invention. In addition, a cost-effective vibrator is hereby provided. In addition, in use, the required duration for the rotation process is thereby limited so that the entire process of arranging a foundation element can be carried out more efficiently.

A further additional advantage of the vibrating device according to the present invention is that the frame can be provided in relatively simple manner with more than one vibratory block, for example two, four or even more. This makes it possible to use a greater capacity for introducing a foundation element in an effective manner. In such an embodiment with several vibrating blocks, use is preferably made of a basic frame and a so-called "spreader bar".

In an advantageous preferred embodiment according to the present invention, the clamping mechanism comprises: a frame provided with a number of cylinders; a plurality of clamping means operatively connected to the cylinders for clamping a foundation element; Positioning means operatively connected to the clamping means such that the clamping means engage around an edge of the foundation element; and connecting means connected to the frame for connecting the frame to the vibrating device.

By providing clamping means, preferably in the form of grippers, or "grippers", it is achieved that a foundation pile of different dimensions and / or configurations can be clamped. This makes flexible use of the device according to the invention possible. Use is herein preferably made of a number of preferably hydraulic cylinders for handling the required forces.

In particular, the device according to the invention is suitable for clamping a foundation pile provided with a flange at the end of the foundation pile directed upwards in use. Such a flange is advantageous for placing a windmill thereon or thereon. Such a windmill can be effectively placed in this way. Due to the flexible device according to the invention, such a foundation pile provided with a flange can be placed in an effective and efficient manner in a substrate, both on land and at sea.

It has been found that by the device according to the invention forces which are developed by a vibrating block arranged with the connecting means during the placement of a foundation element in a substrate can be effectively transmitted to the foundation element, in particular a tubular foundation pile provided with a flange on which a windmill can be placed.

In an advantageous preferred embodiment use is made of two cylinders, which are preferably arranged substantially horizontally.

It has been found that by providing at least two cylinders per clamping means, a proper operation of the device is achieved. The cylinders shift the clamping means so as to bring them over a flange and subsequently allow them to engage on, for example, a tube wall of the foundation pile. Due to the preferably substantially horizontal arrangement of the cylinders, a simple configuration and operation of the device according to the invention is realized.

In an advantageous preferred embodiment according to the invention, the clamping means comprise a clamping mechanism and second positioning means for positioning a clamping mechanism relative to a wall of the foundation element.

By providing a clamping mechanism and second positioning means, greater flexibility of the device according to the invention is obtained. The clamping mechanism is preferably driven by a separate hydraulic cylinder.

In a further advantageous preferred embodiment according to the invention, the vibrating device comprises an auxiliary frame configured for arranging the vibrating device thereon in a wholly or partly lying position of the foundation element on the auxiliary frame.

By using an auxiliary frame, often also referred to as an "up-end frame", a vibrating device can be arranged on or on a foundation element while the foundation element is located on the auxiliary frame in a non-vertical position. By using the auxiliary frame, it is achieved that the provision of the vibrating device on the foundation element can be carried out in a simpler manner. By subsequently rotating the assembly of vibrating device and foundation element with the aforementioned blocking / pretensioning on the spring elements, the assembly is brought into the desired substantially vertical vibrating position, whereby no undesired effects occur on (parts of) the vibrating device due to the relatively large forces that occur during the rotation movement. In addition to greater safety, a relatively long lifespan of the vibrating device is hereby also achieved, whereby a minimum of maintenance work will suffice.

Preferably, the rotation mechanism is configured such that after applying the vibrator to the foundation element, the vibrator and foundation element assembly rotates through an angle to a substantially vertical vibration position in the range of 60 to 85 degrees, preferably in the range of 70 to 70 degrees. 83 degrees, and most preferably about 80 degrees.

A special advantage of handling an angle of rotation in said ranges, in particular about 80 degrees, is that the vibrating device can be fitted to the foundation element in a relatively simple manner. In particular, the vibrating device can, as it were, be guided self-aligning or self-seeking in a tubular foundation element. The required movements and associated applied forces are hereby limited in comparison with the provision of a vibrating device on a completely horizontally placed foundation element, wherein, for example, the vibrating device must be pulled into the foundation element.

A further advantage of rotating through an angle in said ranges, in particular about 80 degrees, is that this results in a more effective balance of forces, in particular in an offshore application. The foundation element can be placed in the auxiliary frame and, due to the angle applied to the horizontal plane, it can already be positioned with a lower end in the water or close to the water surface. This has the advantage that the upward force of the water reduces the required lifting forces. This makes positioning simpler and, in addition, mutual movement of components is further prevented.

The invention further relates to a kit comprising a fixation mechanism configured for applying a blocking or movement restriction to the spring elements, and connecting elements for applying the fixation mechanism to a vibrating device for providing a vibrating device as described above.

The kit offers the same advantages and effects as described for the vibrator. In particular, the kit can be used as a separate built-in or build-up unit that can optionally be mounted on a vibrating device. The kit according to the invention hereby has the additional advantage that it is also suitable for use on already existing vibrating devices that can be modified with it, for example if these are to be used for offshore applications.

The invention furthermore also relates to a method for placing a foundation element in a substrate, the method comprising providing a device and / or vibrating device as described above.

The method offers the same advantages and effects as described for the device and / or vibrator.

The method according to the invention preferably comprises applying a blocking / pretensioning to the spring elements with the fixing mechanism. This achieves the aforementioned advantages and effects with respect to the vibrating device.

Furthermore, the method according to the invention comprises of rotating the assembly of vibrating device and foundation element after applying the blocking / pretensioning and clamping the foundation element to a substantially vertical vibrating position. The vibrating block is herein preferably fixed and rotated for mounting, with which unwanted movements are prevented during rotation and hoisting during positioning of the vibrating device with foundation element.

This arrangement of the vibrator on the foundation element in a non-vertical position followed by rotation of the assembly is particularly advantageous in the case of offshore placement of foundation elements. In this case, it is possible, for example, to arrange the vibrating device on or on the foundation element substantially on board a ship, and preferably substantially on or near the deck of such a ship. In a presently preferred embodiment, this method uses an auxiliary frame, or so-called "up-end frame". Hereby, a foundation element can be arranged in a controlled manner in a subsurface, such as a seabed.

The method according to the invention preferably comprises positioning the clamping means with the positioning means, and preferably with the clamping means, preferably with the aid of the clamping mechanism, driven by a separate hydraulic cylinder, around or around an edge of the foundation element to to grip on preferably a wall of a tubular foundation element. Such an edge in particular comprises a flange and such a foundation element in particular comprises a tubular foundation pile provided with such a flange.

Further advantages, features and details of the invention are elucidated on the basis of a preferred embodiment thereof, wherein reference is made to the accompanying figures, in which: figure 1 ad, views of a conventional vibratory block and an optional clamping system according to the invention; Figure 2 ad, a view of a vibrator with optional clamping system and a spring system according to the invention; Figure 3a, views of a preferred embodiment of the vibrating device according to the invention; Figure 4 shows a view directed at a clamping system usable in a vibrating device according to the invention. figure 5 AF, a view of the clamping system of figure 4; and figure 6, a schematic view of a windmill placed according to the invention.

Vibration system 2 (Figure 1 a) comprises a so-called "outer suppressor" 4 which is connected via spring element 6 to the so-called "inner suppressor" 8. This "inner suppressor" 8 is mounted on crankcase 10. By using spring element 6, the transmission of vibrations while driving foundation element 12 can be isolated from hoisting installation. Connections between inner suppressor 8, crankcase 10, basic frame 14, clamps 16 of clamping mechanism 18, and foundation pile 12 are rigid. Generated vibrations with vibrating device 2 are therefore only brought into foundation pile 12.

Conventional spring system 20 (Figure 1b) with spring element 6 and "inner suppressor" 8 shows a flexible suspension. Two-phase system 22 (Fig. 1c) shows spring system 22 with spring element 6. Spring system 22 is a kind of two-phase system with first-phase element 24 which forms a relatively flexible connection which in particular isolates vibrations to hoisting installation 26. This is therefore particularly relevant when driving pile 12 or being driven into or into the ground. Second phase element 28 realizes a stiffer connection that is not addressed during the vibrating process and precisely during a pulling process with foundation pile 12 so that a higher load can be lifted.

During the so-called "up-lifting", a skew position 30 (Fig. 1d) is in practice created because of the great weights of the assembly of foundation pile 12 and vibrating device 2, great forces are exerted on vibrating device 2, including also the spring elements 6, for example in the form of rubber blocks. Hereby a moment effect on spring elements 6 is created such that they are skewed. Skew 30 can become so large that the two suppressors come into contact with each other. This leads to undesirable and sometimes unacceptable stresses in the structure. Spring element 6 will further be overloaded such that even internal connections can be damaged. This limits the service life of, in particular, the vibratory blocks and thus the usability of such a conventional device.

A vibrating device according to the invention will be explained below with which skew 30 is prevented and preferably can even be avoided.

In the embodiment shown according to the invention, vibrating device 32 (Figure 2 ad) comprises, in addition to the regular components such as outer suppressor 34 and crankcase 36, and components used in a preferred embodiment of the invention, such as base frame 14 and clamps 16 of clamping mechanism 18 , furthermore an adjustable two-phase spring system 38.

Spring system 38 is provided with adjustment mechanism / fixation mechanism 40 (figures 2 b and d). Adjustment mechanism 40 makes it possible to realize a rigid connection between outer suppressor 34 and crankcase 36, whereby the mutual distance is reduced. In the embodiment shown, in addition, the center of gravity 42 is brought closer to the rotation point of the 'up-endening' which favorably influences the rotation from a loading position to a vibrating position of the assembly of vibrating device 32 and foundation pile 12. The flexible connection is spared by the activated rigid connection and damage to it is therefore prevented. In the vibrating position, adjusting mechanism 40 is converted and spring elements 6 will provide a flexible connection.

In the embodiment shown, adjusting mechanism 40 is designed with a type of cylinder, wherein an adjusting mechanism 40 is provided on either side of vibrating device 32, therefore two in total per vibrating device 32. For the rotation of vibrating device 32 during "up-lifting", use is made of rotary cylinder 44 which allows a rotation between vibrating device 32 and hoisting device 26. With the aid of cylinder 44, the vibrating device 32 can make a rotational movement with respect to the hoisting frame 28. This enables the so-called "up-lifting" of the vibrating device 32 assembled with a foundation element 12. The stroke of cylinder 44 is preferably limited to such a length that even with a defective cylinder 44 no undesired rotations between vibrating device 32 and hoisting frame 28 are possible.

Vibration device 32 according to the invention (Figure 3Ah) shows hoisting device 28 in which "outer suppressor" 34 and crankcase 36 are flexibly connected (Figure 3a). By moving adjusting mechanism 40 in direction A, the flexible connection is made rigid by applying a bias to spring elements 6 (Figure 3b). Subsequently, a rotation is carried out of vibrating device 32 relative to hoisting device 28 in direction B by movement, in particular sliding, of cylinder 44 (Fig. 3c). In the embodiment shown, an angle α of about 80 degrees is used. Hereby a searching or self-directing effect is realized during the installation of vibrating device 32 on or in foundation pile 12 (figure 3d) in or on auxiliary frame 46, followed by clamping with clamps 16. Optionally, self-seekers are used to further optimize this effect. Herewith it is avoided that separate tensile forces have to be exerted in order to pull vibrating device 32 to foundation pile 12. It has been found that this self-seeking effect can in particular be used effectively in the case of foundation elements which are provided with a flange on the upper edge. Incidentally, this effect can also be applied advantageously to other foundation elements.

After this, the "up-lifting" (Fig. 3e) can be performed in direction C. Arrived in the vibrating position (Fig. 3f), adjustment mechanism 40 is converted to realize a flexible connection with spring elements 6. After this, foundation pile 12 can be vibrated into substrate 48 in direction D (Figure 3g), with any supports 50, if any. After reaching the desired depth, the vibrating device 32 is removed from foundation pile 12 in direction E (Figure 3h) and then, for example, deployed on, for example, a next foundation pile 12 to be brought into substrate 48.

Optionally, four vibrating blocks 32 are placed next to each other on base frame 14. This distributes forces as optimally as possible. The basic frame comprises beams for distributing the forces exerted on the foundation element, in particular the foundation pile 12 or foundation tube. For this purpose clamping mechanism 18 is designed with, in the embodiment shown, twelve clamping means or clamps 16, a further embodiment of which is explained below. In the embodiment shown, clamps 16 are designed in such a way that they can engage in relatively simple manner over a possible flange arranged on an upper edge of the foundation pile 12. This makes the construction of a construction, such as a windmill, on the foundation element at a later stage. considerably easier. In the embodiment shown, terminals 16 are connected with a bolt connection to base frame 14.

The spring elements 6, which in the embodiment shown are designed as a kind of rubber blocks of an elastomeric material, ensure that vibrations are in use exerted on foundation pile 12 and are not unnecessarily passed on to the other parts of the total vibrating installation. With the aid of two cylinders / adjusting mechanisms 40, a bias can be applied to these spring elements 6 such that movement of spring elements 6 during positioning is thereby prevented. To this end, the cylinders 40 are retractable, with cylinders 40 for example engaging a pin / shaft which subsequently presses spring elements 6 by moving the first part 34 and the second part 36 of the vibrating device 32 towards each other. It will be clear that also a different number of cylinders 40 and another configuration in which, for example, cylinders 40 directly engage on spring elements 6 according to the invention are possible.

In the following the placing of a foundation pile in the form of a tubular element in an offshore application with the aid of the vibrating device and the method according to the invention will be further elaborated in an application in which a foundation element is used as foundation for a windmill. It will be clear that measures of the various embodiments shown according to the invention can be interchanged or otherwise combined. For example, the clamping system, which is explained in more detail below, can be used as a clamping system in the preceding embodiment.

System 102 (Figure 4) is provided with a lifting system 104, one or more vibrating blocks 106, in the shown embodiment four vibrating blocks 106 that are positioned next to each other, a so-called box structure 108 and a device 110 according to the invention for clamping from a foundation pile 112 and in particular onto a flange 114 thereof. In the embodiment shown, pile 112 is placed at sea 116 in subsurface 118. Device 110 is provided with a connecting frame 120 and additional or alternative "structure" 108 to which various clamping elements 122 are arranged.

In the embodiment shown, clamping element 122 (Fig. 5 AF) comprises a fixed outer part 124 and a slidable inner part 126, wherein parts 124, 126 are slidably provided with two cylinders 128. When fitting element 122, parts 124, 126 are first taken apart and placed over flange 114. Subsequently, the parts 124, 126 with cylinders 128 are pushed towards each other and fixed to pole 112 with movable clamp 129. In the embodiment shown, movable clamp 129 is moved with the aid of cylinder 130 and an actual clamping on post 112 is realized. In order to prevent displacement of slidable clamping part 126, fixation elements 132 comprising a separate cylinder are provided in the shown embodiment which fix clamping part 126 relative to T-shaped guide rails 134.

In the embodiment shown, flange protectors 136 are also provided to prevent damage to flange 114. Connection points 38 are furthermore provided on clamping element 122 for directly or indirectly mounting the other components of the vibration system thereon. In the embodiment shown, connecting points 140 are provided around which, for example, windmill 142 can be placed and / or possibly clamping system 122 can be fixed.

In the embodiment shown, the inner diameter of flange 14 is approximately 4400 mm and the outer diameter of approximately 5500 mm.

A windmill (Figure 6) is placed at sea 116 in subsurface 118. Here, windmill is mounted on flange 114 of post 112.

The invention is by no means limited to the above described preferred embodiments thereof. The requested rights are determined by the following claims within the scope of which many modifications are conceivable.