Method of Manufacturing a Connection Between Two Tube Segments of a Tower-Like Structure

Abstract

Method for manufacturing a connection between two tube segments of a tower-like structure, in particular a wind power plant, in which a first tube segment is pushed into a second tube segment at the end face and an annular space is formed between the tube segments, two at least partially circumferential joining elements spaced apart from one another in the longitudinal direction of the tube segments are arranged in the annular space, the joining elements being arranged on an outer wall and/or on an inner wall of one of the tube segments, the tube segments are coupled together via the joining elements, and a mechanical parameter of the mechanical coupling between the tube segments is detected via at least one sensor on at least one of the tube segments, the annular gap being filled with casting compound after initial installation of the structure based on the mechanical parameter.

Claims

1. A method for manufacturing a connection between two tube segments of a tower-like structure, in particular a wind power plant, in which a first tube segment is pushed into an end face of a second tube segment or a first tube segment is slipped over the end face of the second tube segment and an annular gap is formed between the first and second tube segments, two joining elements spaced apart from one another in a longitudinal direction of the tube segments are arranged in the annular gap, the joining elements being arranged on an outer wall of one of the tube segments and/or on an inner wall of one of the tube segments, the tube segments being mechanically coupled to one another via the joining elements in the annular gap, and a mechanical parameter of the mechanical coupling between the tube segments being detected via at least one measuring sensor on at least one of the tube segments, wherein depending on the detected mechanical parameter, the annular gap is filled with casting compound in time after an initial installation and commissioning of the structure.

2. The method of claim 1, wherein the tube segments are mechanically coupled together by the joining elements in a double-slip joint fashion.

3. The method of claim 1, wherein the joining elements corresponding to each other at the tube segments, are arranged so that the mutually corresponding joining elements are in contact with each other in a coupled state.

4. The method of claim 1, wherein at least one of the joining elements tapers in the direction of an end face of the tube segment.

5. The method of claim 1, wherein as a mechanical parameter of at least one of expansion of the tube segment, compression of the tube segment, vibration of the tube segment, acceleration of the tube segment, relative movement of the tube segments to each other, a eigenfrequency of the structure, a change in the eigenfrequency of the structure, a response behavior, especially in the frequency range of the structure, a stress/strain value of the tube segment.

6. The method of claim 1, wherein the detected mechanical parameter is compared with a set point value and, in the event of a deviation above a limit value, the annular gap is filled with casting compound.

7. The method of claim 1, wherein a time gradient of the detected mechanical parameter is compared with a set point value and, in the event of a deviation above a limit value, the annular gap is filled with casting compound.

8. The method of claim 1, wherein the stability of the casting compound is determined depending on a given remaining service life of the structure and decreases with decreasing remaining service life.

9. The method of claim 1, wherein steel tube segments or reinforced concrete are used as tube segments and/or cylindrical or conical tube segments are used as tube segments at least in the area of the annular gap and/or tube segments of an offshore structure are used as tube segments and/or tower segments of a wind turbine, in particular an offshore wind turbine, are used as tube segments.

10. The method of claim 1, wherein the tube segments are positioned concentrically to each other, forming the annular gap between the tube segments.

11. The method of claim 1, wherein the outer tube segment and/or inner tube segment has at least one thrust rib in the region of the annular gap, wherein in particular the at least one thrust rib is arranged at least substantially circumferentially on the tube segment, in particular that the at least one thrust rib is arranged at least substantially annularly on the tube segment.

12. The method of claim 1, wherein a casting mortar and/or a grout is used as the casting compound, in particular that a grout which expands during curing, a so-called expansive grout, is used, and/or that a grout with alkali-silica reactive aggregates, admixtures of bentonite, calcium sulfoaluminate cements and/or aluminate is used.

13. The method of claim 1, wherein a casting mortar and/or a grout is used as casting compound with a cube compressive strength of more than 60 MPa, preferably more than 90 MPa, in particular more than 90 MPa.

14. The method of claim 1, wherein the structure is an offshore structure and that the mechanical coupling between the tube segments is arranged below the water level.

15. The method of claim 1, wherein a distance between the two joining surfaces in the longitudinal direction to each other in the annular gap is made in such a way that it is at least 0.5 times a diameter of the inner tube segment, preferably at least 1 times the diameter of the inner tube segment, in particular at least 1.5 times the diameter of the inner tube segment, preferably not more than 3 times the diameter of the inner tube segment.

16. The method of claim 1, wherein a ratio between an outer diameter of the annular gap and its radial expansion is such that it is at least 20.

17. The method of claim 1, wherein the casting compound is introduced into the annular gap via an opening in the inner tube segment or that the casting compound is introduced into the annular gap via an opening in at least one of the joining elements.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In the following, the subject matter is explained in more detail with reference to a drawing showing embodiments. The drawing shows:

[0054] FIG. 1 is an offshore wind turbine according to an embodiment;

[0055] FIG. 2 is two tube segments slid into each other according to one embodiment;

[0056] FIG. 3 is two tube segments slid into each other according to one embodiment; and

[0057] FIG. 4 is the sequence of a process according to the subject matter.

DETAILED DESCRIPTION

[0058] FIG. 1 shows a wind turbine 2, which is installed offshore. The foundation structure of the wind turbine 2 has a monopile 4. The monopile 4 is a tube segment which is founded in the seabed 6. The way a monopile 4 is founded in a seabed 6 is known per se.

[0059] A transition piece 8 is arranged on the monopile 4 below or above the water level, which is also a tube segment. A boot landing platform 8a can be provided on the transition piece 8.

[0060] A tower 10 of the wind turbine, on which the wind turbine with a nacelle 12 is arranged, is attached to the transition piece 8. The basic structure of the wind turbine 2 with tower 10 and nacelle 12 is known per se.

[0061] Monopile 4 and transition piece 8 are described below by way of example. The description also applies mutatis mutandis to other tube segments of a structure, such as a drilling platform or the like.

[0062] The connection between the monopile 4 formed as a tube segment and the transition piece 8 formed as a tube segment is explained in more detail by way of example for all conceivable tube segments.

[0063] In the following description, the Transition Piece 8 is always inserted as the upper tube segment into the Monopile 4 as the lower tube segment. However, the description also applies mutatis mutandis to the case where the transition piece 8 is slipped over the monopile 4 as the lower tube segment. An essential feature of this process is that the connection between the tube segments, in this case between the monopile 4 and the transition piece 8, is designed as a double-slip joint and an annular space between the tube segments can be filled between the joining elements as required depending on measured values and mechanical parameters after startup.

[0064] FIG. 2 shows a longitudinal section through such a connection. The monopile 4 is shown with a first joining element 14a arranged on its inner lateral surface in the area of a front face opening 4a. In the example shown, the first joining element 14a is formed by a corresponding profiling of the opening cross section of the tubular element. A second joining element 14b is arranged on the inner wall of the monopile 4 at a distance in the longitudinal direction 18 from the front face opening 4a. The two joining elements 14a, b have a taper in the direction of the front face opening 4a and are preferably conically shaped.

[0065] The Transition Piece 8 has joining elements 16a and 16b on its outer lateral surface. The joining element 16a is at a front face opening 8a of the transition piece 8. Here, too, the joining element 16a can be formed by a corresponding profiling of the wall of the transition piece 8 in the region of the front face opening 8a. At a distance in the longitudinal direction 18 from the front face opening 8a, a further joining element 16b is formed on the outer lateral surface of the transition piece 8. The joining elements 16a, b also have a taper in the direction of the front face opening 8a and are preferably conical.

[0066] The preferably conical tapers of the joining elements 14a, 16b and 14b, 16a respectively have corresponding, complementary profiles. This means that in the inserted state the joining elements 14a, 16b and 14b, 16a are in direct contact with each other at their mutually facing surfaces, the so-called joining surfaces. The joining elements 14, 16 are shaped in such a way that in the installed state an annular space 20 is formed between the tube segments, in particular the transition piece 8 and the monopile 4. In the transition piece 8, an opening 22 is provided on the wall which can be opened and/or closed from the inside in order to be able to fill the annular space 20 with casting compound, as will be described below.

[0067] FIG. 3 shows a further example of a monopile 4 with a transition piece 8 inserted therein. In contrast to FIG. 2, the joining elements 14a, 16b are not arranged directly at the front edge of transition piece 8 or monopile 4, but offset from the front edge in the longitudinal direction 18. Again, the joining elements 14a, 16b as well as 14b, 16a are complementary to each other, so that in the joined state corresponding joining surfaces abut each other. Here, too, an annular space 20 is formed.

[0068] FIG. 4 shows a sequence of an method according to the subject matter. In a step 30, a simulation of a connection between two tube segments 4, 8, in particular according to FIGS. 2 and 3, is first carried out in order to check their load-bearing capacity and mechanical reaction to mechanical loading. Here, the most diverse mechanical parameters, already mentioned above, are simulated and it is simulated within which limits the parameters may move without damaging the structure. Set point values or set point value ranges are simulated for the most diverse parameters, which indicate how the mechanical parameter can change or in which range the mechanical parameter can lie without the structure being damaged.

[0069] With the values thus obtained, a connection between Monopile 4 and Transition Piece 8 is actually built in a step 32. Here, the structure is actually built in-situ and put into operation. During construction, in a step 34, at least one measuring sensor, preferably a plurality of measuring sensors, are arranged on the tube segments 4, 8 and/or the joining elements 14, 16.

[0070] After commissioning, the measured values detected by the sensors are continuously monitored in step 36. In each case, a measurement can be taken after a defined time interval (1 minute, 5 minutes, 15 minutes or similar) or a permanent measurement can be taken. The measured values detected correspond to the previously simulated mechanical parameters.

[0071] In a step 38, the detected mechanical parameter is compared with the simulated set point value or set point value range. If the actual value is within the set point value or set point value range, in particular below or above a limit value, the system branches back to step 36 in 38a. If, however, it occurs that one or more of the parameters is outside the set point range or outside a set point by a limit value, in a step 38b the system branches to step 40.

[0072] In step 40, a warning signal is output, which in step 42 causes the annular space 20 to be casting compounded with a casting compounding compound, in particular.

[0073] For this purpose, an installation crew is commissioned to carry out grouting on the structure that has already been erected. For this purpose, the assembly team preferably travels to the structure with an appropriate assembly ship. Via an opening not shown, a supply line is brought up to the opening 22 inside the transition piece 8. The opening 22 is opened and casting compound is poured into the annular space 20 through the opening 22. After the annular space 20 is preferably completely filled, the opening 22 is closed again and the casting compound is allowed to cure. After the casting compound has cured, a grout joint is formed. This grout joint is mechanically designed so that the casting compound has sufficient strength to protect the structure from damage. This strength is selected so that the structure is mechanically stable until the end of its predicted service life.

[0074] With the aid of the process shown, it is thus possible to use double slip joints already in the field without actually having any knowledge of their long-term stability. If such structures run the risk of damage or have already suffered damage in the course of their service life, in particular to the double slip joint, the present process enables subsequent casting compounding so that the double slip joint becomes a casting compound joint that ensures sufficient mechanical stability for the rest of its service life.

[0075] All references, including publications, patent applications, and patents cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

[0076] It should be understood that the figures illustrate exemplary embodiments in detail, and it should be understood that the present application is not limited to the details or methodology set forth in the description or illustrated in the figures. It should also be understood that the terminology is for purpose of description only and should not be regarded as limiting.

[0077] The use of the terms a and an and the and similar referents in the context of describing the invention (especially in the context of the following claims) is to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms comprising, having, including, and containing are to be construed as open-ended terms (i.e., meaning including, but not limited to,) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., such as) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0078] Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context