JP4850151B2 - Hybrid tower for wind power generation and its construction method - Google Patents

Description

  The present invention relates to a hybrid tower for wind power generation and a method for constructing the hybrid tower.

  Conventionally, wind power plants in Japan have been constructed by selecting locations with good location conditions that can receive sufficient wind. However, the tower for wind power generation to be constructed in the future may be constructed in a place where the wind speed is low. When the building is constructed in a place where the wind speed is low, the higher the wind speed is, the larger the height of the tower becomes.

For example, Patent Document 1 discloses a method of constructing a tower for wind power generation by an on-site PC concrete method. In this method, the tower is made of cylindrical cast-in-place concrete, and the frame is tensioned by a medium cable system. In this way, it is assumed that the tower will be made larger by using on-site PC concrete.
In addition, there are also proposed ones in which the entire tower is constructed of steel pipes, and as shown in Patent Document 2, the lower part of the tower is made of a PC or PRC member and the upper part is made of a steel member.
JP 2005-248687 A Registered Utility Model No. 3074144

However, in particular, when a wind power generation tower exceeding 70 m is made of a steel structure, the diameter of the tower becomes large, and restrictions are imposed on the transportation to the installation place, making transportation difficult.
Moreover, when it was set as the steel structure, the thickness of the steel plate became thick, and processing this into a cylinder shape accompanied the difficulty on processing.
Further, when the concrete structure is used, the rigidity of the tower for wind power generation is increased, but there is a drawback that the inertia force at the time of earthquake is also increased due to the weight of the concrete. In addition, when the concrete structure is used, there is a drawback that the construction period for the construction is longer than that when the steel structure is used.
Furthermore, in the case where the lower part of the tower shown in Patent Document 2 is a PC or PRC member and the upper part is made of a steel member, there is no specific description of the joint between the concrete tower and the steel tower. When the horizontal part at the top of the concrete tower and the horizontal flange at the bottom of the steel tower are joined as described in, there is usually a problem that air bubbles etc. stay in the non-shrink mortar filled on the lower surface of the flange did.

  The present invention has been proposed in view of the above, and the lower part of the tower for wind power generation has a highly rigid concrete structure, and the upper part of the tower has a steel structure with excellent workability, and the concrete tower and the steel tower It is an object of the present invention to provide a hybrid tower for wind power generation in which the joint portion has a shape such as bubbles that can be easily removed, wind resistance stability and earthquake resistance are improved, and local stress at the joint portion can be suppressed.

  In order to achieve the above object, the present invention is a hybrid tower for wind power generation in which a base end portion is made of prestressed concrete and a steel cylinder is added to form a hollow tower, the prestressed concrete and the steel The cylinder is connected via an adapter ring having a fixing portion for introducing prestress, and the lower surface of the flange formed at the lower end of the adapter ring has a curved surface shape convex downward.

  Moreover, in this invention, the ratio for which the said prestressed concrete accounts with respect to a height direction is the range of 85% or less, It is characterized by the above-mentioned.

  In the present invention, the prestressed concrete is installed on the footing and tensions the fixed steel fixing device embedded in the footing and the PC steel material inserted through the top end of the prestressed concrete. This is characterized by prestressing.

  Moreover, in this invention, the said PC steel materials are connected with the coupler installed in a part of said prestressed concrete inner peripheral wall, It is characterized by the above-mentioned.

  Further, in the present invention, a footing construction process for constructing a footing and installing a fixed side fixing device in the footing, a concrete in which an inner mold frame and an outer mold frame are assembled on the footing, and concrete is sequentially placed vertically. An adapter ring provided with a fixing portion is installed on the top of the concrete tube that has reached a predetermined length, and a PC steel material is inserted between the fixed-side fixing device and the fixing portion to tension the PC steel material. Thus, it is characterized by comprising a pre-stress introduction step of introducing pre-stress into the concrete cylinder portion, and a steel cylinder attachment step of vertically adding a steel cylinder on the adapter ring.

  In the present invention, in the concrete placing step, a PC steel material insertion sheath is disposed in the axial direction of the concrete cylinder.

  Since this invention consists of an above-described structure, there can exist an effect which is demonstrated below.

  The present invention is a hybrid tower for wind power generation in which a base end portion is made of prestressed concrete and a steel cylinder is added thereon to form a hollow tower, and the prestressed concrete and the steel cylinder are introduced with prestress. It is connected via an adapter ring equipped with a fixing part to make the bottom surface of the flange formed on the lower end of the adapter ring a convex curved surface. A hybrid tower for power generation can be provided. In addition, since the flange lower surface has a curved surface shape that protrudes downward, and the bubbles are not retained in the non-shrinkable mortar, the shape can be easily removed, so that the bondability can be improved. Furthermore, local stress can be prevented from occurring in the non-shrink mortar. Therefore, it is possible to provide a hybrid tower for wind power generation that is resistant to earthquakes and typhoons and has excellent workability. In addition, the construction period can be shortened and the construction cost can be reduced.

  Moreover, in this invention, since the ratio for which the said prestressed concrete accounts with respect to a height direction is the range of 85% or less, while improving the rigidity of the lower end part of a tower, the workability of an upper end part can be improved. .

  Further, in the present invention, the prestressed concrete is installed on the footing and tensions the fixed steel fixing device embedded in the footing and the PC steel material inserted through the top end of the prestressed concrete. Therefore, prestress can be applied to the concrete structure. Moreover, there is no need to provide a tendon gallery for tensioning the PC steel material in the footing.

  In the present invention, since the PC steel is connected by a coupler installed on a part of the inner wall of the prestressed concrete, the PC steel that extends from the dead anchor in the footing and the PC steel that prestresses the concrete structure portion. Can be easily connected, and workability can be improved.

  Further, in the present invention, a footing construction process for constructing a footing and installing a fixed-side fixing device in the footing, and a concrete in which an inner mold frame and an outer mold frame are assembled on the footing and a concrete cylinder is sequentially placed vertically. An adapter ring equipped with a fixing part is installed at the top of the concrete tube that has reached a predetermined length, and a PC steel material is inserted between the fixed-side fixing device and the fixing part, and the PC steel material is tensioned. As a result, it is composed of a pre-stress introduction process for introducing pre-stress into the concrete cylinder part, and a steel cylinder mounting process in which a steel cylinder is vertically added on the adapter ring. The tower can be a hybrid tower of concrete and steel. Moreover, it is possible to efficiently construct a hybrid tower for wind power generation that is resistant to earthquakes and typhoons.

  Further, in the present invention, in the concrete cylinder placing step, the PC steel material insertion sheath is disposed in the axial direction of the concrete cylinder, so that the PC steel material can be easily inserted and the prestressing operation to the concrete structure portion is performed. Can be easily done.

  85% or less of the lower part of the tower is made of a concrete structure, and the remaining upper part is made of a steel structure to increase the rigidity with the heavy concrete as the lower part, with the lighter steel structure up, making it earthquake and wind resistant. Stability and workability can be improved.

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating an embodiment. FIG. 1 is a cross-sectional view of an essential part showing an example of a hybrid tower for wind power generation according to the present invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG. Here, the hybrid tower 10 for wind power generation includes a base end portion 11 made of prestressed concrete and a steel cylinder 12 added to form a hollow tower, and the prestressed concrete and the steel cylinder 12 are added. Are connected via an adapter ring 14 having a fixing portion 13 for introducing prestress.

  The proportion of the base end portion (prestressed concrete) 11 in the height direction is set to a range of 85% or less. For example, in the case of a tower having a height of 100 m, a concrete structure having high rigidity is set to 85 m or less from the bottom, and a steel cylindrical structure having excellent workability is set to 15 m or more on the top. Thus, wind resistant stability and seismic resistance can be improved by installing concrete which is heavy at the lower end and is resistant to buckling and a light steel cylinder is disposed at the upper end. In addition, the ratio of a concrete part and a steel part is determined in consideration of structural stability, workability, and economical efficiency. By lengthening the concrete part, the rigidity of the entire tower is increased and the natural frequency is increased. The natural frequency of the entire tower is selected so that resonance can be avoided in consideration of the rotation speed of blades (blades) to be attached, the mass of the nacelle, and the like.

  The base end portion (prestressed concrete) 11 is installed on a footing 15 in which a fixed side fixing device (dead anchor) 16 is embedded. A PC steel material 17 extends upward from the fixed-side fixing device 16 via a sheath. Further, a PC steel material insertion sheath 18 is disposed in the axial direction of the concrete tube of the base end portion 11. Moreover, the PC steel material 17 is connected by the coupler 20 installed in a part of inner peripheral wall of the base end part (prestressed concrete) 11 of the 1st step, for example.

  3A is an explanatory view showing the coupler joint box, FIG. 3B is a cross-sectional perspective view showing the coupler, and FIG. 4 is a cross-sectional view taken along the line CC of FIG. The coupler joint box 19 is disposed so as to open to the inner peripheral wall of the first-stage base end portion 11. In the coupler joint box 19, the PC steel material 17 is connected by a plurality of couplers 20. The coupler 20 is inserted into the outer cylinder 20a, the inner cylinder 20b screwed to the inner circumference of the outer cylinder from both ends, and the tapered inner circumference of the inner cylinder 20b, and the PC steel material 17 is narrowed at the center. The locking member 20c is held and fixed. The inner cylinder 20b is screwed with the inner circumference of the outer cylinder 20a with screws formed on the outer circumference, and has a tapered inner circumference that expands toward one of the axes. The locking member 20c has a frustoconical member divided into two along the axial direction, and includes a through hole 20d that holds the PC steel material 17 in the center. In addition, a plurality of irregularities are formed in the through hole 20d. The irregularities may be annular.

  The coupler 20 configured as described above is arranged in the coupler joint box 19 and sandwiches the end of the PC steel material with the divided locking member 20c. The locking member 20c holding the end of the PC steel material is inserted into the tapered inner periphery of the inner cylinder 20b. Similarly, the locking member 20c holding the end of another PC steel material 17 is inserted into the inner periphery of the inner cylinder 20b and connected by the outer cylinder 20a. A plurality of couplers 20 are disposed in the coupler joint box 19.

  5 is a cross-sectional view taken along line BB in FIG. 1, and FIG. 6 is an enlarged vertical cross-sectional view showing the adapter ring portion in FIG. The top end of the base end 11 is filled with about 50 mm of non-shrink mortar 21, and the adapter ring 14 is temporarily adjusted on the top. After the non-shrinkable mortar 21 exhibits a predetermined strength, the PC steel material 17 inserted through the fixed side fixing device 16 of the footing 15 is pretensioned to the base end portion 11 by tensioning it with a hydraulic jack or the like not shown. Add stress.

  The adapter ring 14 has flanges 14a and 22 at the upper and lower ends, respectively. The flange 14a at the lower end is formed as a curved surface 14b whose bottom surface is convex downward. In addition, the flange 14 a is pressure-bonded to the prestressed concrete portion by a fixing tool 40 that fixes the upper end of the PC steel material 17. The fixing tool 40 is disposed on the annular flange 14a at substantially equal intervals. In addition, the stress level of the joint surface during rated operation is set to be equal to or lower than the allowable stress level of concrete. A steel cylinder 12 is sequentially bolted onto the adapter ring 14 via flanges 22 and 23. The steel cylinder 12 is connected until the hybrid tower 10 for wind power generation reaches a predetermined height.

  Next, the hybrid tower for wind power generation configured as described above can suppress the increase in weight and keep the increase in inertial force during an earthquake while maintaining rigidity.

  Next, the construction procedure of the hybrid tower for wind power generation according to the present invention will be described with reference to FIGS. In FIG. 7, an internal scaffold 24 preliminarily assembled on the first-stage base end portion 11 in which a reinforcing bar, a sheath, and the like are placed between an inner mold frame and an outer mold frame to form concrete is lifted by a crane 25. Then, it is fixed using the embedded insert 26.

  In FIG. 8, an external scaffold 27 corresponding to a change in the outer diameter of the tower is attached with a crane 25. In FIG. 9, the pre-assembled inner mold 28, the reinforcing bar 29, and the sheath 18 are installed with a crane via a dedicated lifting jig 30. Connect to the reinforcing bar and sheath of the block (base end) installed below.

  In FIG. 10, the outer mold 31 is set while being hung with a wire 32 via a hanging jig 30. At this time, the target 33 installed at the center of the inner mold 28 and the target 34 installed at the center of the inner scaffold 24 are measured by the surveying instrument 35 to ensure the accuracy of the construction of the inner and outer molds. A bracket scaffold 36 is attached to the outer mold 31.

  In FIG. 11, concrete is placed from a pump wheel 37 through a pipe 38 and a rubber hose 39 to a site where the inner mold 28 and the outer mold 31 are installed. When placing concrete, the targets 33 and 34 are measured with the surveying instrument 35 as needed to ensure the accuracy of the tower.

  In FIG. 12, the demolding procedure after concrete placement will be described. After the concrete cast by curing exhibits a predetermined strength, the outer mold frame 31 shown in FIG. Thereafter, the inner mold 28 is divided and removed.

  In FIG. 13, the internal scaffold 24 is set using the embedded insert 26 in the newly placed site, and the external scaffold 27 is pulled up to the next work position using the electric chain block 41. The electric chain block 41 is supported by a dedicated metal fitting 42 attached to the top end of the concrete portion.

  In FIG. 14, after raising the position of the external scaffold 27, it moves to the process for placing concrete of the next hierarchy, and repeats the above process one by one, and the prestressed concrete part is constructed.

  In this way, when the concrete portion (base end portion) is completed, as described in FIG. 6, the top end of the base end portion 11 is filled with the non-shrink mortar 21, and the adapter ring 14 is adjusted on the top. Temporarily install. At this time, since the lower surface of the flange 14a is formed as a downwardly convex curved surface 14b, bubbles and the like do not remain in the non-shrink mortar 21. Moreover, it can suppress that local stress arises in a non-shrink mortar by setting it as a curved surface. After the filled non-shrink mortar 21 exhibits a predetermined strength, the PC steel material 17 inserted through the fixed side fixing device 16 of the footing 15 is tensioned with a hydraulic jack or the like not shown in the figure to the base end portion 11. Apply prestress.

  Further, a steel cylinder is sequentially added onto the adapter ring 14 by fixing the flange with bolts.

  FIG. 15 is a completed view showing a state in which the base end portion 11 made of prestressed concrete is constructed on the footing 15, the steel adapter ring 14 and the steel cylinder 12 are constructed thereon, and the nacelle is installed. . The hybrid tower 10 for wind power generation configured as described above calculates the natural frequency from the rigidity of each member and prevents the occurrence of resonance.

  In addition, although the above Example demonstrated the example which made the lower surface of the flange formed in the adapter ring lower end into the convex curved surface shape downward, it is good also as a downward convex polygonal shape. For example, a pentagon or a hexagon. Further, since it is not necessary to provide a tendon gallery for tensioning the PC steel material inside the footing, the footing height can be lowered and maintenance can be facilitated.

FIG. 1 is a cross-sectional view of an essential part showing an example of a hybrid tower for wind power generation according to the present invention. 2 is a cross-sectional view taken along line AA in FIG. Fig.3 (a) is explanatory drawing which shows a coupler joint box, (b) is a cross-sectional perspective view which shows a coupler. FIG. 4 is a cross-sectional view taken along the line CC of FIG. 5 is a cross-sectional view taken along line BB in FIG. FIG. 6 is an enlarged longitudinal sectional view showing the adapter ring portion in FIG. 1. FIG. 7 is an explanatory view showing a construction procedure of the hybrid tower for wind power generation. FIG. 8 is an explanatory view showing a construction procedure of the hybrid tower for wind power generation. FIG. 9 is an explanatory diagram showing a construction procedure of the hybrid tower for wind power generation. FIG. 10 is an explanatory diagram showing a construction procedure of the hybrid tower for wind power generation. FIG. 11 is explanatory drawing which shows the construction procedure of the hybrid tower for wind power generation. FIG. 12 is explanatory drawing which shows the construction procedure of the hybrid tower for wind power generation. FIG. 13 is an explanatory view showing a construction procedure of the hybrid tower for wind power generation. FIG. 14 is an explanatory diagram showing a construction procedure of the hybrid tower for wind power generation. FIG. 15 is an explanatory view showing a completed state of the hybrid tower for wind power generation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Hybrid tower 11 for wind power generation Base end part 12 Steel cylinder 13 Fixing part 14 Adapter ring 15 Footing 16 Fixed side fixing apparatus (dead anchor)
17 PC steel material 18 Sheath 19 Coupler joint box 20 Coupler 20a Outer tube 20b Inner tube 20c Locking member 20d Through hole 21 Non-shrink mortar 22 Flange 23 Flange 24 Internal scaffold 25 Crane 26 Embedded insert 27 External scaffold 28 Inner frame 29 Reinforcing bar 30 Hanging jig 31 External mold 32 Wire 33 Target 34 Target 35 Surveying instrument 36 Bracket scaffold 37 Pump car 38 Piping 39 Rubber hose 40 Fixing tool 41 Electric chain block 42 Dedicated metal fittings

Claims (6)

A hybrid tower for wind power generation in which a base end portion is composed of prestressed concrete and a steel cylinder is added to form a hollow tower,
The prestressed concrete and the steel cylinder are connected via an adapter ring having a fixing portion for introducing prestress, and the flange lower surface formed at the lower end of the adapter ring has a curved surface shape convex downward. A hybrid tower for wind power generation.   The hybrid tower for wind power generation according to claim 1, wherein a ratio of the prestressed concrete with respect to a height direction is in a range of 85% or less. The prestressed concrete is installed on a footing, and a fixed-side fixing device embedded in the footing;
The hybrid tower for wind power generation according to claim 1 or 2, wherein prestress is applied by tensioning a PC steel material that is inserted through the top end portion of the prestressed concrete.   The hybrid tower for wind power generation according to any one of claims 1 to 3, wherein the PC steel material is connected by a coupler installed on a part of the inner peripheral wall of the prestressed concrete. In addition to constructing a footing, a footing construction process in which a fixed fixing device is installed in the footing,
A concrete cylinder placing process for assembling an inner mold frame and an outer mold frame on the footing and placing concrete cylinders in order vertically;
An adapter ring having a fixing portion at the top of the concrete cylinder that has reached a predetermined length and having a bottom surface of the flange formed at the lower end with a convex curved surface downward is installed, and PC steel is placed between the fixing side fixing device and the fixing portion. By inserting and tensioning this PC steel material, from the prestress introduction step of introducing prestress into the concrete tube, and the steel cylinder mounting step of vertically adding a steel cylinder on the adapter ring The construction method of the hybrid tower for wind power generation.   6. The construction method for a hybrid tower for wind power generation according to claim 5, wherein a sheath for inserting a PC steel material is disposed in the axial direction of the concrete cylinder in the concrete cylinder placing step.

Images