JP6786419B2 - Wind power generator construction method and wind power generator construction structure - Google Patents

Description

The present invention relates to a method for constructing a wind power generator having a foundation to be placed underwater, and a construction structure for the wind power generator.

The introduction of wind power generators has been promoted for some time, and the number of wind power generators installed is steadily increasing. However, on land, the number of places where wind power generators can be placed is decreasing, and when wind power generators are placed in mountainous areas, road maintenance is required and costs increase. .. Therefore, the introduction of offshore wind turbines, that is, wind turbines with foundations that are placed underwater, rather than onshore, is underway.

Japanese Unexamined Patent Publication No. 2003-28046 describes a support structure for a wind turbine for wind power generation installed above a breakwater. This support structure includes one support leg fixed to the breakwater and the other support leg fixed to the seabed ground via a waste stone mound and foundation skeleton. A support column extending in the vertical direction is provided on one support leg and the upper portion of the other support leg, and a generator and a propeller are provided on the upper end of the support column. In this support structure, one of the support legs is fixed to the breakwater, so that a part of the load of the wind turbine is borne by the breakwater, and the construction cost of the wind turbine and the like is reduced.

Japanese Unexamined Patent Publication No. 2003-28046

However, in general, the breakwater has a structure that can withstand a horizontal force, and does not have a structure that can withstand a pushing force or a pulling force. In addition, since the breakwater moves with the passage of a long period of time, there is a concern that the support structure described above may lack the balance of proof stress. Therefore, when a large wind power generator is installed, the balance may be greatly lost, and there is a problem that the large wind power generator cannot be installed in the above-mentioned support structure. In particular, since the size of wind power generators has been increasing in recent years, there is a tendency that a new wind power generator cannot be installed in the above-mentioned support structure. Therefore, there is also a problem that the above-mentioned support structure cannot cope with a new wind power generator.

An object of the present invention is to provide a method for constructing a wind power generator and a structure for constructing a wind power generator, which can be installed with a large-scale wind power generator and can be adapted to a new wind power generator. ..

The method for constructing a wind power generator according to the present invention is a method for constructing a wind power generator provided above an existing foundation placed in water, and the existing foundation is left and the existing foundation is used as an existing wind power generator. It is provided with a step of removing the wind turbine, a step of placing a new foundation around the existing foundation, and a step of installing a connecting member for connecting the upper part of the existing foundation and the upper part of the new foundation.

In this method of constructing a wind power generator, the existing foundation is left in the water and the existing wind power generator is removed from the existing foundation. Therefore, since the existing foundation is not removed, the existing foundation can be effectively used. In this construction method, a new foundation is placed around the existing foundation, and a connecting member for connecting the existing foundation and the new foundation is installed on the upper part of the existing foundation and the upper part of the new foundation. In this way, it is possible to install a connecting member on the upper part of a plurality of foundations and install a new wind power generator on the connecting member, and by having a plurality of foundations, a large wind power generator can be connected. It can be installed on a member. Therefore, even if the size of the wind power generator is increased, the number of foundations can be increased according to the size of the wind power generator, and the problem that a new wind power generator cannot be installed can be avoided. .. Therefore, it is possible to surely correspond to a new wind power generator. Further, since the arrangement mode of the new foundation can be appropriately designed so as to reduce the load acting on the existing foundation, the yield strength can be reliably maintained even after a long period of time.

Further, the existing foundation may include existing piles that are driven into water, and the new foundation may include new piles that are driven into water. In this way, each foundation can include a pile to be driven into the water.

Further, in the process of placing a new foundation, a plurality of new foundations may be placed. In this case, since the existing foundation and the new foundation can be combined into three or more foundations, the bearing capacity can be further enhanced. Therefore, it is possible to build a foundation that is easier to handle with a large wind power generator.

In addition, a step of arranging a connecting material for connecting the existing foundation and the new foundation may be provided before the new foundation is placed. In this case, the upper part of the existing foundation and the upper part of the new foundation can be connected by a connecting member, and the existing foundation and the lower part of the new foundation can be connected by a connecting material. Therefore, the rigidity of the wind power generator as a whole can be increased by the connecting member and the connecting member.

Further, the above-mentioned step of arranging the connecting material includes a step of attaching the connecting material to the existing foundation, and in the step of placing the new foundation, the new foundation may be placed in the connecting material. In this case, a wind power generator having high rigidity can be efficiently constructed by attaching a connecting material to the existing foundation and placing a new foundation in the connecting material.

In addition, the new foundation includes a new pile to be driven underwater and a transition piece fixed to the new pile and connecting members. In the process of placing the new foundation, a grout is formed between the transition piece and the new pile. The material may be injected to fix the transition piece to the new pile. In this case, even if the new pile is struck diagonally in water and the verticality of the new pile is lowered, the transition piece is interposed between the new pile and the connecting member to be above the transition piece. The verticality can be ensured. Therefore, a more stable wind power generator can be constructed. Further, by injecting a grout material between the transition piece and the new pile, the transition piece and the new pile can be easily fixed.

Further, in the step of installing the connecting member, the existing foundation and the new foundation may be connected on the water, and a new wind power generator may be assembled on the upper part of the connecting member. In this case, by connecting the existing foundation and the new foundation with a connecting member and assembling a new wind power generator on the upper part of the connecting member, a wind power generator having higher rigidity can be easily constructed.

The construction structure of the wind power generator according to the present invention is a construction structure of a wind power generator provided above an existing foundation placed in water, and is a blade, nacelle and tower of a first-generation wind power generator. The existing foundation that was removed , the second-generation new foundation that was placed around the existing foundation, the upper part of the existing foundation, and the upper part of the new foundation are connected, and the second-generation wind power generator is installed. It includes a connecting member to be assembled.

The construction structure of this wind power generator includes an existing foundation and a new foundation placed around the existing foundation underwater. Therefore, the existing foundation can be effectively used. In addition, this construction structure includes a connecting member that connects the upper part of the existing foundation and the upper part of the new foundation. Therefore, the connecting member is installed on the upper part of the plurality of foundations, and the new wind power generator is assembled on the connecting member. Therefore, since the multiple foundations are used, a larger wind power generator is generated on the connecting member. The machine can be installed. Therefore, even if the size of the wind power generator is increased, the number of foundations can be increased according to the size of the wind power generator, and the problem that a new wind power generator cannot be installed can be avoided. .. Therefore, it is possible to surely correspond to a new wind power generator.

According to the present invention, a large-scale wind power generator can be installed and a new wind power generator can be supported.

It is a side view which shows the wind power generator to which the construction method and construction structure which concerns on 1st Embodiment are applied. It is a side view which shows the existing foundation in which the wind power generator of FIG. 1 is installed. It is a perspective view which shows the wind power generator to which the construction method and construction structure which concerns on 1st Embodiment are applied. It is a side view which shows the construction structure of the wind power generator of FIG. It is a top view which shows the construction structure of the wind power generator of FIG. It is a vertical sectional view which shows a pile and a transition piece. (A) and (b) are plan views which show the process of the construction method of the wind power generator of FIG. It is a side view which shows the wind power generator to which the construction method and construction structure which concerns on 2nd Embodiment are applied. It is a vertical cross-sectional view which shows the pile and the foundation superstructure of the construction structure which concerns on the modification. (A), (b) and (c) are plan views which show the construction method which concerns on the modification.

Hereinafter, an embodiment of a construction method and a construction structure of a wind power generator according to the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are designated by the same reference numerals, and duplicate description will be omitted.

(First Embodiment)
First, the wind power generator according to the first embodiment will be described. FIG. 1 is a side view showing a wind power generator before applying the construction method of the present embodiment, and FIG. 2 is a side view showing an existing foundation on which the wind power generator of FIG. 1 is installed. As shown in FIGS. 1 and 2, the wind power generator 1 according to the present embodiment is provided on the seabed B, for example, and performs offshore wind power generation. However, the wind power generator 1 is not limited to the ocean, and may be installed in water different from the ocean, such as a lake, a river, a coast, or a harbor. The wind power generator 1 is a first-generation wind power generator.

The wind power generator 1 includes a tower 3 fixed to an existing foundation 2, a nacelle 4 attached to the upper part of the tower 3, and a blade 5 attached to the nacelle 4. The tower 3, which is the first generation tower, is made of, for example, concrete or steel plate. A generator, a speed increaser, and the like are housed inside the nacelle 4, and the rotor shaft projects from the speed increaser to the outside of the nacelle 4. The blade 5 is fixed to the rotor shaft of the nacelle 4. The first generation wind power generator 1 includes, for example, three blades 5. When the blade 5 receives the wind and rotates, this rotation is increased to a constant rotation speed by the speed increaser in the nacelle 4, and the rotational motion is converted into electric power by the generator in the nacelle 4. As an example, the diameter of the rotor combined with the blades 5 is 80 m, and the rated output of the wind power generator 1 is 2 MW.

The nacelle 4 is provided with an anemometer and an anemometer, and efficiently generates electricity by controlling the direction of the rotor and the angle of the blade 5 according to the wind speed and the wind direction. That is, the wind power generator 1 uses natural energy and responds to the ever-changing wind speed and direction, and controls the direction of the rotor and the angle of the blade 5 to generate electric power efficiently.

The tower 3 is easily shaken because a large blade 5 and a nacelle 4 equipped with various devices are placed on the uppermost part, and further, a vibration load is generated by the wind acting as an external force and the rotation of the blade 5 that receives the wind. Continue to receive. Therefore, since the tower 3 is susceptible to fatigue damage due to vibration load, the design of the tower 3 is to check the safety against short-term loads such as during a storm and an earthquake, and to check the safety due to the wind received during the service life. We are checking.

For example, in the fatigue check due to the vibration of the tower 3, the cumulative damage degree is D, the number of repetitions for each vibration load acting during the set useful life is _nij , and the fatigue strength curve obtained by a fatigue test or the like is obtained. _Assuming that the fatigue life is _Nij , the cumulative damage degree D is evaluated by the following formula (1).

In the formula (1), the value obtained by dividing the number of repetitions n _ij by the fatigue life N _ij is integrated for all vibration loads to obtain the cumulative damage degree D. If the cumulative damage degree D is 1 or less, it can be determined that fatigue fracture does not occur. The wind used for the study actually changes irregularly, but it is assumed by the statistical probability distribution.

Further, since the tower 3 is designed according to the useful life of the wind power generator 1, after the useful life of the wind power generator 1 has passed, the tower 3, the nacelle 4 and the blade 5 are removed to perform the second generation. Need to build a wind power generator. The useful life of the wind power generator 1 is, for example, 20 years from the start of operation. In addition, the load continuously received by the tower 3 is calculated from the data continuously measured by the wind direction and anemometer of the nacelle 4. Further, a speedometer, an accelerometer and a strain gauge for measuring the actual vibration history and calculating the cumulative damage degree D may be provided inside the tower 3, and the speedometer, the accelerometer and the strain gauge may be provided. The measured value may be accumulated for a certain period of time.

The first-generation wind power generator 1 has, for example, a monopile foundation type, and is provided above one existing foundation 2. The existing foundation 2 includes an existing pile 2a, which is a monopile cast in the underwater W, and a transition piece 2b extending upward from the existing pile 2a and connected to the lower end of the tower 3. The existing pile 2a is driven into the seabed B. The existing foundation 2 may be provided with a jacket-type offshore wind power foundation instead of the monopile foundation type.

A scouring prevention work 6 is provided around the existing pile 2a on the seabed B, and the scouring prevention work 6 prevents scouring of the ground around the existing pile 2a on the seabed B. The scouring prevention work 6 is, for example, a net bag containing crushed stone. The existing pile 2a has, for example, a circular cross-sectional shape when cut on a horizontal plane. The diameter of the existing pile 2a is, for example, 4 m or more, and the existing pile 2a is a large-diameter pile. The transition piece 2b is provided to ensure the verticality of the existing foundation 2. Further, a work space 2c such as a handrail and a landing is provided at the upper end of the existing foundation 2.

As described above, the existing wind power generator 1 as described above reaches the design life 20 years from the start of operation, and is therefore removed after the design life is reached. In this removal, it is possible to pull out the existing foundation 2. However, as described above, since the existing pile 2a has a large diameter, it is difficult to pull out the existing pile 2a and it costs a lot of money.

Further, there is a method of cutting the existing pile 2a near the seabed B and removing the structure above the seabed B, but leaving the existing pile 2a in the ground. However, in this case, the new pile must be installed while avoiding the remaining existing pile 2a. In addition, the position of the remaining existing pile 2a may not be known, and the remaining existing pile 2a may protrude from the seabed B in the future. If the remaining existing pile 2a protrudes on the seabed B, a problem such as a net being caught may occur, which may affect the fishery or the like.

In order to avoid the above problems, in the present embodiment, the existing foundation 2 is diverted as a part of the foundation in the second generation wind power generator without removing the existing foundation 2. Hereinafter, the second generation wind power generator having the construction structure according to the present embodiment will be described.

As shown in FIGS. 3 and 4, the construction structure of the second-generation wind power generator 11 is constructed so as to be in a tripile shape having three foundations. The wind power generator 11 is provided on a pile-type foundation (new foundation 12 and existing foundation 2) composed of a plurality of piles (new pile 12a and existing pile 2a). Further, in the second-generation wind power generator 11, the point of action, the direction of action, the pile support mechanism, etc. of the maximum stress acting on the existing foundation 2 are different from those of the first-generation wind power generator 1. Has been done.

The wind power generator 11 is provided in the foundation superstructure 13 (connecting member) that connects the upper part of the existing foundation 2 placed in the underwater W and the upper part of the new foundation 12 placed around the existing foundation 2. .. The wind power generator 11 includes a tower 14, which is a second-generation tower fixed to the foundation superstructure 13, a nacelle 15 attached to the upper part of the tower 14, and a blade 16 attached to the nacelle 15.

Each of the tower 14, nacelle 15 and blade 16 of the second generation wind power generator 11 has at least the same functions as the tower 3, nacelle 4 and blade 5 of the first generation wind power generator 1. .. Therefore, the description of the functions of the tower 14, the nacelle 15, and the blade 16 will be omitted as appropriate. Further, particularly in recent years, the size of the newly installed wind power generator 11 has increased, and the diameter of the rotor combined with the blades 16 can be, for example, 160 m. The rated output is also increased, and the rated output of the wind power generator 11 is, for example, 6 MW or 8 MW. Therefore, the load of the newly installed wind power generator 11 is gradually increasing.

In view of such circumstances, in the present embodiment, even if the load of the wind power generator 11 becomes large, the load can be dispersed, and further, the existing foundation 2 can be effectively used without being removed. There is. In addition, the number and location of the new foundation 12 will be changed as appropriate according to the size and weight of the tower 14, nacelle 15, and blade 16 placed above, which will affect the remaining existing foundation 2. It is possible to reduce it.

The construction structure of the second generation wind power generator 11 includes, for example, a tripile foundation including one existing foundation 2 and two new foundations 12. As shown in FIG. 5, in a plan view, one existing foundation 2 and two new foundations 12 are arranged so as to form a triangular shape. The existing foundation 2 and the new foundation 12 are connected by a connecting member 17 in the underwater W. The new foundation 12 includes a new pile 12a to be driven into the underwater W, a new pile 12a, and a transition piece 12b fixed to the foundation superstructure 13. Further, at the upper end of the new foundation 12, a work space of 12 g such as a handrail and a landing is provided.

The connecting material 17 is a pile connecting material that connects the existing pile 2a and the new pile 12a with underwater W. Further, the connecting material 17 is a guide material that guides the position of the new pile 12a to be driven after the fact. The connecting member 17 has a triangular shape in a plan view. The connecting member 17 connects the mounting portion 17a attached to the existing pile 2a, the driving portion 17b into which the new pile 12a is driven, the first connecting portion 17c connecting the mounting portion 17a and the driving portion 17b, and the driving portion 17b to each other. It has a second connecting portion 17d.

The mounting portion 17a has an annular shape that surrounds the existing pile 2a. The inner diameter of the mounting portion 17a is, for example, about 20 cm larger than the outer diameter of the existing pile 2a. The mounting portion 17a has a structure in which the annular member is divided in half, and the first semicircular portion 17e which is semicircular in a plan view and the second half which is continuous with the two first connecting portions 17c. It has a circular portion 17f. The first semicircular portion 17e and the second semicircular portion 17f are joined to each other by, for example, bolting while surrounding the existing pile 2a. The joining work by bolting is performed by, for example, a diver who has submerged in the underwater W.

The driving portion 17b has an annular shape, and the inner diameter of the driving portion 17b is, for example, about 20 cm larger than the outer diameter of the new pile 12a. As described above, since the inner diameter of the driving portion 17b is larger than the outer diameter of the new pile 12a, it is possible to drive the new pile 12a inside the driving portion 17b.

The first connecting portion 17c extends linearly between the mounting portion 17a and the driving portion 17b, and the second connecting portion 17d extends linearly between the two driving portions 17b. The first connecting portion 17c and the second connecting portion 17d may be a plate-shaped steel material or a box-shaped steel material. As an example, the first connecting portion 17c and the second connecting portion 17d may have a hollow structure such as a truss structure, and in this case, it is possible to suppress the influence on the flow of water in the water W. Further, a scouring prevention work 18 is provided around the existing pile 2a and the new pile 12a on the seabed B, and the scouring prevention work 18 allows the ground to be scoured around the existing pile 2a and the new pile 12a. It is prevented. The structure of the scouring prevention work 18 may be the same as the structure of the scouring prevention work 6 described above, for example.

As shown in FIG. 6, the transition piece 12b is fixed to the upper end of the new pile 12a. The transition piece 12b is provided to ensure the verticality of the new foundation 12. Therefore, even if the new pile 12a is driven into the seabed B at a slight angle, the verticality of the new foundation 12 is ensured. The new pile 12a and the transition piece 12b are both tubular, for example, and the new foundation 12 has a double pipe structure.

The outer diameter of the new pile 12a is smaller than the inner diameter of the transition piece 12b, and the difference between the outer diameter of the new pile 12a and the inner diameter of the transition piece 12b is, for example, about 10 cm. At the upper end of the new pile 12a and the lower end of the transition piece 12b, a grout material G is driven between the outer peripheral surface of the new pile 12a and the inner peripheral surface of the transition piece 12b. The new pile 12a and the transition piece 12b are fixed to each other by the grout material G.

The upper end of the transition piece 12b is provided with a diameter-expanded portion 12h whose diameter increases upward, and a protruding portion 12j at the upper end of the diameter-expanding portion 12h which projects inward in the radial direction of the transition piece 12b. The diameter-expanded portion 12h includes an inclined portion 12k that gradually expands in diameter toward the upper side of the transition piece 12b, and a side surface portion 12m that extends upward from the inclined portion 12k and has a constant diameter.

The protruding portion 12j has an annular shape in a plan view. The work space 12g described above is provided on the upper surface of the protrusion 12j. Further, a fixing portion 12n for fixing the lower end of the foundation upper structure 13 is provided inside the projecting portion 12j in the radial direction with respect to the working space 12g. Further, the lower portion of the foundation upper structure 13 is tubular, and the foundation upper structure 13 has a protruding portion 13a protruding inward in the radial direction of the foundation upper structure 13 at the lower end thereof. The protruding portion 13a has, for example, an annular shape in a plan view. Further, the projecting portion 13a is a portion fixed to the fixing portion 12n, and the projecting portion 13a and the fixing portion 12n are joined to each other with bolts V and nuts in a state of being vertically overlapped with each other, so that the new foundation 12 The foundation superstructure 13 is fixed to the base.

As shown in FIGS. 3 to 5, the foundation superstructure 13 connects the new foundation 12 and the existing foundation 2 to each other on the water. The foundation superstructure 13 includes a tower fixing portion 13b to which the tower 14 is fixed, and a plurality of foundation connecting portions 13c extending radially from the tower fixing portion 13b in a plan view. The tower fixing portion 13b is provided, for example, in the center of the foundation superstructure 13 in a plan view, and the lower end of the tower 14 is fixed to the tower fixing portion 13b. The foundation connecting portion 13c has a first extending portion 13d extending linearly from the tower fixing portion 13b and a second extending portion 13e extending downward from the end of the first extending portion 13d. The above-mentioned protruding portion 13a is provided at the lower end of the second extending portion 13e.

Next, a method of constructing the wind power generator 11 according to the present embodiment will be described. Hereinafter, a method for constructing the first-generation wind power generator 1 to the second-generation wind power generator 11 will be described. First, the yield strength possessed by the existing foundation 2 of the first generation is evaluated, and the number and arrangement of the new foundations 12 are set so as to match the yield strength possessed by the existing foundation 2. Then, for example, when the wind power generator 1 has reached the end of its life, the blade 5, the nacelle 4, and the tower 3 are removed from the existing foundation 2 (the step of removing the existing wind power generator). At this time, the existing foundation 2 is left as it is.

Next, as shown in FIG. 7A, the connecting material 17 is attached to the existing foundation 2 (a step of arranging the connecting material, a step of attaching the connecting material to the existing foundation). Specifically, the mounting portion 17a is attached to the existing pile 2a by bolting the existing pile 2a in a state where the first semicircular portion 17e and the second semicircular portion 17f surround the existing pile 2a. The grout material G is injected between the mounting portion 17a and the existing pile 2a to fix the existing pile 2a to the mounting portion 17a. At this time, since the positions of the mounting portion 17a, the driving portion 17b, the first connecting portion 17c, and the second connecting portion 17d are determined, the positions of the existing pile 2a and the new pile 12a are determined.

Then, as shown in FIG. 7B, a new pile 12a is driven into each driving portion 17b, and a transition piece 12b is attached to the upper end of the new pile 12a. At this time, the grout material G is injected between the driving portion 17b and the new pile 12a to fix the new pile 12a to the driving portion 17b, and further, the grout material is applied to the outer peripheral surface of the new pile 12a and the inner peripheral surface of the transition piece 12b. By injecting G, the transition piece 12b is fixed to the new pile 12a. As described above, the connecting material 17 is attached to the existing foundation 2, and the new foundation 12 is driven into the connecting material 17 to construct the new foundation 12 (process of placing the new foundation).

Subsequently, as shown in FIGS. 3, 4 and 6, the foundation superstructure 13 is installed on the upper part of the existing foundation 2 and the upper part of the new foundation 12. Specifically, the projecting portion 13a of the foundation superstructure 13 is placed on the fixing portion 12n at the upper end of the new foundation 12, and the fixing portion 12n and the projecting portion 13a are joined to each other with bolts V and nuts to form the new foundation 12. The foundation superstructure 13 is fixed to the upper end. Similarly, the foundation superstructure 13 is fixed to the upper end of the existing foundation 2 (step of installing the connecting member). After that, the construction of the wind power generator 11 is completed by assembling the tower 14 to the tower fixing portion 13b located at the upper end of the foundation superstructure 13 and assembling the nacelle 15 and the blade 16 to the tower 14.

Next, the method of constructing the wind power generator 11 according to the present embodiment and the action and effect obtained from the construction structure of the wind power generator 11 will be described in detail.

In the method for constructing the wind power generator 11 and the construction structure for the wind power generator 11, the existing foundation 2 is left in the underwater W, and the existing wind power generator 1 is removed from the existing foundation 2. Therefore, since the existing wind power generator 1 is removed and the existing foundation 2 is not removed, the existing foundation 2 can be effectively used. Therefore, in order to leave the existing foundation 2 of the first generation and use the existing foundation 2 as a part of the new foundation of the second generation wind power generator 11, the cost of removing the foundation and the cost of constructing the new foundation Can be suppressed.

In this construction method, a new foundation 12 is driven around the existing foundation 2, and a foundation superstructure 13 that connects the existing foundation 2 and the new foundation 12 is installed above the existing foundation 2 and above the new foundation 12. In this way, the foundation superstructure 13 can be installed on the plurality of foundations, and the new wind power generator 11 can be installed on the foundation superstructure 13, and the number of foundations is large. The wind power generator 11 can be installed on the foundation superstructure 13.

Therefore, even if the size of the wind power generator 11 is increased, the number of foundations can be increased according to the size of the wind power generator 11 and the like, so that the problem that a new wind power generator 11 cannot be installed is avoided. be able to. Therefore, it is possible to reliably correspond to the new wind power generator 11. Further, since the arrangement mode of the new foundation 12 can be appropriately designed so as to reduce the load acting on the existing foundation 2, the proof stress can be reliably maintained even after a long period of time. As described above, since the degree of freedom in designing the second-generation new foundation 12 is high, it is possible to reduce the need to consider the size and working load of the future wind power generator 11 at the time of the first foundation design. Therefore, for example, it is possible to mount a large-scale wind power generator, which has become popular in 20 years, on the new foundation 12.

Further, the existing foundation 2 includes an existing pile 2a placed in the underwater W, and the new foundation 12 includes a new pile 12a placed in the underwater W. In this way, it is possible to include a pile to be driven into the underwater W.

Further, in the process of placing the new foundation, a plurality of new foundations 12 are placed. Therefore, the existing foundation 2 and the new foundation 12 can be combined to form three or more foundations, so that the bearing capacity can be further enhanced. Therefore, it is possible to build a foundation that is easier to handle with the large wind power generator 11.

Further, a step of arranging the connecting member 17 connecting the existing foundation 2 and the new foundation 12 is provided before the new foundation 12 is placed. Therefore, the upper part of the existing foundation 2 and the upper part of the new foundation 12 can be connected by the foundation superstructure 13, and the lower part of the existing foundation 2 and the new foundation 12 can be connected by the connecting material 17. Therefore, the rigidity of the wind power generator 11 as a whole can be increased by the foundation superstructure 13 and the connecting member 17. Specifically, since the plurality of new piles 12a and the existing piles 2a are fixed by the lower connecting member 17 and the upper foundation upper structure 13, the construction structure of the wind power generator 11 above the seabed B is integrated. It can be made to resist external force.

Further, the step of arranging the connecting material includes the step of attaching the connecting material 17 to the existing foundation 2, and in the step of placing the new foundation 12, the new foundation 12 is placed on the connecting material 17. Therefore, the wind power generator 11 having high rigidity can be efficiently constructed by attaching the connecting member 17 to the existing foundation 2 and placing the new foundation 12 on the connecting member 17.

Further, the new foundation 12 includes a new pile 12a to be driven into the underwater W, a new pile 12a, and a transition piece 12b fixed to the foundation superstructure 13, and in the process of driving the new foundation 12, the transition piece The grout material G is injected between the 12b and the new pile 12a to fix the transition piece 12b to the new pile 12a. Therefore, even if the new pile 12a is struck diagonally in the underwater W and the verticality of the new pile 12a is lowered, the transition piece 12b is interposed between the new pile 12a and the foundation superstructure 13. , The verticality above the transition piece 12b can be secured. Therefore, a more stable wind power generator 11 can be constructed. Further, by injecting the grout material G between the transition piece 12b and the new pile 12a, the transition piece 12b and the new pile 12a can be easily fixed.

Further, in the process of installing the foundation superstructure 13, the existing foundation 2 and the new foundation 12 are connected on the water, and the new wind power generator 11 is assembled on the upper part of the foundation superstructure 13. Therefore, by connecting the existing foundation 2 and the new foundation 12 with the foundation superstructure 13 and assembling the new wind power generator 11 on the upper part of the foundation superstructure 13, the wind power generator 11 having higher rigidity can be easily obtained. Can be built.

Further, in the existing monopile existing pile 2a, a large overturning moment from the wind power generator 1 is predominant, whereas in the plurality of piles (two new piles 12a and the existing pile 2a) in the group pile type foundation, the large overturning moment is predominant. The pushing force (or pulling force) in the vertical direction and the horizontal force are outstanding. In this way, by switching from the wind power generator 1 installed on the existing monopile pile 2a to the wind power generator 11 installed on the new pile-type foundation 12, the outstanding moment and force can be changed.

Therefore, for example, the maximum stress point acting on the existing pile 2a used for 20 years and the direction of the acting load can be changed, so that it is easy to design safely for the existing foundation 2. Further, in consideration of the predominant direction of the wind load and the predominant direction of the wave load, it is possible to design to drive the new pile 12a at a position where the load acting on the existing foundation 2 is further reduced. Then, when designing the existing foundation 2 of the first generation, it is possible to carry out a more rational design by giving a likelihood to the fatigue resistance in consideration of the wind power generator 11 of the second generation.

(Second Embodiment)
Next, the construction structure and construction method of the wind power generator 21 according to the second embodiment will be described with reference to FIG. Hereinafter, the description overlapping with the first embodiment will be omitted as appropriate. The construction structure of the wind power generator 21 according to the second embodiment includes a girder 23 (connecting member) instead of the foundation superstructure 13, and a tower 14, a nacelle 15, and a blade above one new foundation 12. The point that 16 is provided is different from the first embodiment.

As shown in FIG. 8, in the wind power generator 21, the new foundation 12 has a monopile structure, and the existing foundation 2 and the new foundation 12 are connected to each other by a girder 23. The girder 23 connects the existing foundation 2 and the new foundation 12 to each other on the water. The girder 23 extends in the horizontal direction between, for example, the working space 12g of the new foundation 12 and the working space 2c of the existing foundation 2. Further, in the work space 2c of the existing foundation 2, a construction station 22a of the wind power generator 21 or an operation and maintenance station 22b of the wind power generator 21 is provided.

Regarding the method of constructing the wind power generator 21, first, the existing foundation 2 of the first generation is left, and the wind power generator 1 is removed from the existing foundation 2 (the process of removing the existing wind power generator). Then, the new foundation 12 is placed around the existing foundation 2 (the process of placing the new foundation). After placing the new foundation 12, a girder 23 that connects the upper part of the existing foundation 2 and the upper part of the new foundation 12 is installed (process of installing the connecting member), and the tower 14 and the nacelle 15 are installed on the upper part of the new foundation 12. And by assembling the blade 16, the construction of the wind power generator 21 is completed.

As described above, in the construction method and construction structure of the wind power generator 21 according to the second embodiment, the existing foundation 2 is left in the underwater W, and the existing wind power generator 1 is removed from the existing foundation 2. Therefore, since the existing foundation 2 is not removed, the existing foundation 2 can be effectively used. Therefore, as in the first embodiment, since the existing foundation 2 is used as a part of the new foundation of the second generation wind power generator 21, the cost of removing the foundation and the cost of constructing the new foundation can be suppressed. ..

Although the method for constructing the wind power generator and the embodiment of the construction structure according to the present invention have been described above, the present invention is not limited to the above-described embodiments and does not change the gist described in each claim. It may be modified in a range or applied to something else. That is, the present invention can be modified in various ways without changing the gist of each claim.

For example, in the above-described embodiment, the example in which the new pile 12a and the foundation superstructure 13 are fixed via the transition piece 12b has been described, but the transition piece 12b can be omitted. For example, a flange may be provided at the upper end of the new pile 12a shown in FIG. 6 to ensure the verticality of the new pile 12a, and the lower end of the foundation superstructure 13 may be directly joined to the upper end of the new pile 12a.

Further, as shown in FIG. 9, a cone-shaped portion 33 is provided at the lower end of the foundation connecting portion 13c (second extending portion 13e) of the foundation superstructure 13, and the cone-shaped portion 33 is inserted into the new pile 12a from above. Then, the grout material G may be injected and joined between the cone-shaped portion 33 and the new pile 12a. As described above, the means for joining the new foundation 12 and the foundation superstructure 13 (connecting member) can be appropriately changed. Further, in the above-described embodiment, an example in which various members are joined by injecting the grout material G has been described, but a joining means other than the grout material G can also be used.

Further, in the above-described embodiment, an example in which the existing foundation 2 and the new foundation 12 are connected by the connecting member 17 in the underwater W has been described, but the shape, size, arrangement mode, number, and material of the connecting member 17 are appropriately described. It can be changed. Further, the connecting member 17 can be omitted.

Further, in the above-described first embodiment, the wind power generator 11 provided in the tripile structure (three piles 2a, 12a) is constructed from the wind power generator 1 provided in the monopile structure (one existing pile 2a). An example, that is, an example in which the number of foundations before construction is 1 and the number of foundations after construction is 3 has been described. However, the number of foundations before construction and the number of foundations after construction can be changed as appropriate. For example, a tripod type wind power generator may be constructed from a monopile type wind power generator. Further, a tripile type wind power generator or a tripod type wind power generator may be constructed from a gravity type wind power generator or a jacket type wind power generator.

For example, as shown in FIG. 10A, three new foundations 12 may be placed around one existing foundation 2 and the four foundations may be arranged so as to have a rectangular shape in a plan view. Further, as shown in FIG. 10B, three more new foundations 12 may be placed around the three existing foundations 2 and the six foundations may be arranged so as to have a hexagonal shape in a plan view. .. Further, as shown in FIG. 10C, a plurality of new foundations 12 may be placed concentrically on the radial outer side of the plurality of existing foundations 2 having a circular shape in a plan view. In this way, the number of foundations before and after construction and the shape formed by the plurality of foundations can be changed as appropriate. Further, a new wind power generator may be constructed by using the existing foundation 2 of one of the plurality of existing foundations 2 and the new foundation 12.

1,11,21 ... Wind power generator, 2 ... Existing foundation, 2a ... Existing pile, 2b, 12b ... Transition piece, 2c, 12g ... Working space, 3,14 ... Tower, 4,15 ... Nasser, 5,16 ... Blade, 6, 18 ... Scavenging prevention work, 12 ... New foundation, 12a ... New pile, 12b ... Transition piece, 12h ... Diameter expansion part, 12j ... Projection part, 12k ... Inclined part, 12m ... Side part, 12n ... Fixed part, 13 ... Foundation upper structure (connecting member), 13a ... Protruding part, 13b ... Tower fixing part, 13c ... Foundation connecting part, 13d ... First extending part, 13e ... Second extending part, 17 ... Connecting material , 17a ... Mounting part, 17b ... Driving part, 17c ... First connection part, 17d ... Second connection part, 17e ... First half circle part, 17f ... Second half circle part, 22a ... Construction station, 22b ... Operation and maintenance Station, 23 ... girder (connecting member), 33 ... cone-shaped part, B ... seabed, G ... grout material, N ... nut, V ... bolt, W ... underwater.

Claims (8)

It is a method of constructing a wind power generator installed above the existing foundation that is placed underwater.
The process of leaving the existing foundation and removing the existing wind power generator from the existing foundation,
The process of placing a new foundation around the existing foundation and
The process of installing the connecting member that connects the upper part of the existing foundation and the upper part of the new foundation, and
How to build a wind power generator with. The existing foundation includes the existing piles placed in the water.
The new foundation includes a new pile to be driven into the water.
The method for constructing a wind power generator according to claim 1. In the process of placing the new foundation, a plurality of the new foundations are placed.
The method for constructing a wind power generator according to claim 1 or 2. A step of arranging the existing foundation and the connecting material connecting the new foundation is provided before the new foundation is placed.
The method for constructing a wind power generator according to any one of claims 1 to 3. The step of arranging the connecting material includes a step of attaching the connecting material to the existing foundation, and in the step of placing the new foundation, the new foundation is placed on the connecting material.
The method for constructing a wind power generator according to claim 4. The new foundation includes a new pile to be driven into the water and a transition piece fixed to the new pile and the connecting member.
In the step of placing the new foundation, a grout material is injected between the transition piece and the new pile to fix the transition piece to the new pile.
The method for constructing a wind power generator according to any one of claims 1 to 5. In the step of installing the connecting member, the existing foundation and the new foundation are connected on the water, and a new wind power generator is assembled on the upper part of the connecting member.
The method for constructing a wind power generator according to any one of claims 1 to 6. It is a construction structure of a wind power generator installed above the existing foundation that is placed underwater.
With the existing foundation from which the blades, nacelles and towers of the first generation wind power generators have been removed,
The second-generation new foundation placed around the existing foundation,
A connecting member that connects the upper part of the existing foundation and the upper part of the new foundation and is assembled with a second-generation wind power generator.
Construction structure of a wind power generator equipped with.

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