JP2020159131A - Manufacturing method for precast concrete member and manufacturing device for precast concrete member - Google Patents

Abstract

To provide a manufacturing method for precast concrete members and a manufacturing device for precast concrete members that can accurately manufacture cylindrical precast concrete members in a short period using a limited space.SOLUTION: The manufacturing method for precast concrete members comprises: constructing a vertical hole 5 in a ground 3 and inserting a vertical core material 7 into the vertical hole 5; sending vertical reinforcement 29 and lateral reinforcements 31 from the ground 3 into the vertical hole 5 and winding the lateral reinforcements 31 on the vertical reinforcement 29 in order to construct a reinforcement structure 37 in the vertical hole 5; next attaching an outer formwork 23 on outside guide rails 15 provided on an inner surface of the vertical hole 5, attaching an inner formwork 25 on inside guide rails 17 provided on the outer surface of the core material 7, moving the outer formwork 23 and the inner formwork 25 from a lower section of the vertical hole 5 to an upper section, and installing concrete 44 between the outer formwork 23 and the inner formwork 25; and then removing a precast concrete member 2 from the vertical hole 5.SELECTED DRAWING: Figure 4

Description

The present invention relates to a method for manufacturing a cylindrical precast concrete member and an apparatus for manufacturing a precast concrete member.

Conventionally, as a method of constructing a reinforcing bar cage, there is a method of sending a plurality of flexible reinforcing bars into a shaft, arranging them at intervals in the circumferential direction, and winding a band around the plurality of flexible reinforcing bars (for example, Patent Document). 1).

Further, as a floating body construction method of a floating offshore power generation facility, there is a method of arranging concrete rings manufactured in a locally manufactured yard in a horizontal direction and integrating them with PC steel (see, for example, Patent Document 2).

JP-A-2018-172870 Japanese Unexamined Patent Publication No. 2018-173011

For self-supporting ground such as rock and hard ground, it is conceivable to save labor in the field work by pre-drilling and building precast piles made of reinforced concrete or prestressed concrete. However, the reinforcing bar cage described in Patent Document 1 is used when forming a solid cast-in-place pile in a shaft that has been drilled in advance. Patent Document 2 describes a method of constructing a hollow member in a locally manufactured yard, but a wide yard is required because a concrete ring is manufactured and integrated in a state where the axial direction is horizontal. It is difficult to secure. In addition, it is difficult to maintain the roundness of the concrete ring.

The present invention has been made in view of the above-mentioned problems, and an object thereof is a precast concrete member capable of accurately manufacturing a cylindrical precast concrete member in a limited space in a short period of time. It is to provide the manufacturing method of the above and the manufacturing apparatus of the precast concrete member.

In order to achieve the above-mentioned object, the first invention is a method for manufacturing a cylindrical precast concrete member, wherein a shaft is constructed on the ground and a vertical core material is built in the shaft a. Step b of constructing a reinforcing bar arrangement structure in the shaft by winding the horizontal bars around the vertical bars while sending the vertical bars and the horizontal bars from the ground into the shaft, and on the inner peripheral surface of the shaft. The step c of attaching the outer formwork to the provided outer guide rail and attaching the inner formwork to the inner guide rail provided on the outer peripheral surface of the core material, and the outer formwork using the outer guide rail and the inner guide rail. A step d of placing concrete between the outer formwork and the inner formwork while moving the inner formwork from the lower part to the upper part of the shaft, and a step of pulling out a precast concrete member from the shaft. This is a method for manufacturing a precast concrete member, which comprises e and.

In the first invention, by using a shaft constructed on the ground, a precast concrete member can be manufactured in a short period of time by using a limited space in the field as a manufacturing yard. Therefore, it is not necessary to transport and assemble precast concrete from a factory or the like, and there is no need for space for storing or assembling members. In addition, the cross section is cylindrical by placing concrete while moving the outer formwork and inner formwork using the guide rails provided on the inner peripheral surface of the shaft and the outer peripheral surface of the core material built into the shaft. Precast concrete members can be manufactured with high accuracy and can be automated.

In the step b, the end plate is lowered with the lower end of the vertical bar and the lower end of the horizontal bar fixed to the end plate, and the end plate is fixed to the support block provided in the lower part of the shaft. Is desirable.
As a result, the positions of the lower end of the vertical bar and the lower end of the horizontal bar can be determined by using the end plate, and the bottom of the precast concrete member can be reinforced. Further, the length of the precast concrete member can be adjusted by adjusting the height of the support block provided at the lower part of the shaft.

During the step b and the step c, an additional vertical bar may be sent into the shaft from above the ground, and the lower end portion of the additional vertical bar may be fixed to the end plate.
This makes it possible to add vertical bars after constructing the bar arrangement structure.

Between the step b and the step c, a sheath pipe is sent into the shaft from above the ground, the lower end of the sheath pipe is fixed to the end plate, and between the step d and the step e. , The tension material may be inserted into the sheath tube to fix the tension material to the end plate.
By providing a sheath tube and a tensioning material to introduce tensioning force, the thickness of the precast concrete member can be reduced and the weight can be reduced.

In step d, it is desirable to steam-cure the concrete from which the outer formwork and the inner formwork have been removed.
As a result, the strength of concrete can be developed at an early stage.

The precast concrete member is a monopile foundation of the offshore wind turbine, and a tower connection portion for connecting to the tower of the offshore wind turbine between the process d and the process e above the concrete placed in the process d. May be constructed.
This makes it possible to easily manufacture a monopile foundation for an offshore wind turbine to which a tower can be directly connected.

The second invention is an apparatus for manufacturing a cylindrical precast concrete member, which comprises a shaft having a predetermined depth, a core material installed in the shaft in the vertical direction, and from above the ground into the shaft. A vertical bar feeding device for feeding vertical bars, a horizontal bar feeding device for feeding horizontal bars from above the ground into the shaft, and a rotation of rotating the horizontal bar feeding device along the outer circumference of an opening on the ground surface of the shaft. The device, an outer formwork that can be raised and lowered along the outer guide rail provided on the inner peripheral surface of the shaft, and an inner formwork that can be raised and lowered along the inner guide rail provided on the outer peripheral surface of the core material. It is an apparatus for manufacturing a precast concrete member, which is characterized by comprising.

In the second invention, by using the shaft, the precast concrete member can be manufactured in a short period of time by using the limited space in the field as a manufacturing yard. In addition, precast concrete with a cylindrical cross section is made possible by raising and lowering the outer formwork and inner formwork along the guide rails provided on the inner peripheral surface of the shaft and the outer peripheral surface of the core material built into the shaft. The manufacturing members can be manufactured with high accuracy.

It is desirable that a pedestal provided on the ground so as to straddle the shaft is further provided, the upper end of the core material is fixed to the pedestal, and the vertical bar feeding device is attached to the pedestal.
As a result, the upper end of the core material can be securely fixed, and the vertical streak feeding device can be installed on the ground.

It is desirable that the rotating device can be attached with the vertical bar feeding device by removing the horizontal bar feeding device.
As a result, the vertical streak feeding device can be rotationally moved along the outer circumference of the opening on the ground surface of the shaft to feed the vertical streak from a desired position.

It is desirable that the rotating device is a turntable.
As a result, the horizontal streak feeding device can be smoothly rotated to wind the horizontal streak around the vertical streak.

It is desirable that the rotating device is provided with a concrete hopper having an opening / closing function.
As a result, the position of the concrete hopper can be changed by rotating the rotating device when placing concrete. In addition, the concrete hopper can be opened and closed to adjust the amount of casting at each casting location to be even.

It is desirable that the core material is a steel pipe.
As a result, an elevating device or the like can be installed inside the core material.

According to the present invention, it is possible to provide a method for manufacturing a precast concrete member and an apparatus for manufacturing a precast concrete member, which can accurately manufacture a cylindrical precast concrete member in a limited space in a short period of time.

The figure which shows the manufacturing apparatus 1. The figure which shows the manufacturing apparatus 1. The figure which shows the state which fixed the lower end part of the vertical bar 29 and the horizontal bar 31. The figure which shows the state which lowered the end plate 21. The figure which shows the state which the additional vertical bar 29 is arranged. The figure which shows the state which arranges the sheath tube 41. The figure which shows the state which attached the outer form 23 and the inner form 25. The figure which shows the state which attached the outer form 23 and the inner form 25. The figure which shows the state which the concrete 44 is cast. The figure which shows the state which constructed the tower connection part 49. The figure which shows the state which introduced the tension force into the precast concrete member 2. The figure which shows the state which the precast concrete member 2 is pulled out from the shaft 5.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

(1. Manufacturing equipment 1)
1 and 2 are views showing the manufacturing apparatus 1. 1 is a vertical cross-sectional view of the manufacturing apparatus 1, FIG. 2 (a) is a view of the manufacturing apparatus 1 from above, and FIG. 2 (b) is a view showing a cross section by arrows A1-A1 of FIG. (C) is a figure which shows the cross section by arrow A2-A2 of FIG. Further, FIG. 3 is a view showing a state in which the lower ends of the vertical streaks 29 and the horizontal streaks 31 are fixed, and FIG. 3 (a) is a view showing a cross section by arrows B2-B2 of FIG. 3 (b). b) is a figure which shows the cross section by the arrow B1-B1 of FIG. 3 (a).

The manufacturing apparatus 1 is an apparatus for manufacturing a cylindrical precast concrete member 2 (see FIG. 11). As shown in FIGS. 1 to 3, the manufacturing apparatus 1 includes a shaft 5, a core material 7, a gantry 9, a turntable 35, a vertical bar drum 11, a horizontal bar drum 13, an outer form 23, and an inner form 25. It is composed of an end plate 21, a vertical streak template 27, and the like.

The shaft 5 is formed on the ground 3. The ground 3 is, for example, the ground on the back surface of a quay having a depth that allows a large crane vessel to berth. The depth of the shaft 5 is substantially the same as that of the manufactured precast concrete member 2. The diameter of the shaft 5 is set to be 3 to 4 m larger than the manufactured precast concrete member 2.

The shaft 5 is formed by using a known construction method such as a caisson or a continuous wall. The shaft 5 is water-stopped by the side wall 51 and the bottom slab 52. A pump (not shown) having sufficient drainage performance against the inflow of rainwater and overtopping waves is installed in the shaft 5, and the inside is dried up. Foundation concrete 4 is provided on the outer periphery of the opening on the ground surface of the shaft 5.

The core material 7 is installed in the central portion of the shaft 5 in the vertical direction. The core material 7 is a steel pipe. The diameter of the core material 7 is set smaller than the opening at the upper part of the precast concrete member 2 to be manufactured. It is desirable to provide an elevating device for the operator to elevate and lower the inside of the core material 7.

The gantry 9 is provided on the foundation concrete 4 so as to straddle the shaft 5. The gantry 9 includes a main body 91 and a top fixing beam 92 radially provided on the upper surface of the main body 91. The upper end of the core material 7 is fixed to the top fixing beam 92 of the gantry 9. As a result, the position of the core material 7 is securely fixed.

The turntable 35 is a rotating device that rotates along the outer circumference of the opening on the ground surface of the shaft 5. The turntable 35 is provided on the foundation concrete 4 inside the gantry 9. A horizontal bar drum 13 is mainly attached to the turntable 35, but a vertical bar drum 11 and a concrete hopper 43 (see FIG. 9) described later can also be attached.

The vertical bar drum 11 is a vertical bar sending device for sending the vertical bar 29 into the shaft 5 from above the ground 3, and is a drum around which the vertical bar 29 is wound. The vertical bar drum 11 is attached to the inner peripheral surface of the main body 91 of the gantry 9 at a predetermined interval in the circumferential direction of the gantry 9. The vertical streak drum 11 is removable from the gantry 9. A pulley 12 is connected to each vertical bar drum 11. The vertical bar 29 is a strand-shaped reinforcing bar made of a material such as steel, carbon fiber, FRP (fiber reinforced plastic), CFRP (carbon fiber reinforced plastic). The vertical streak drum 11 can also be used to feed the sheath tube 41 (see FIG. 6).

The horizontal bar drum 13 is a horizontal bar sending device for sending the horizontal bar 31 into the shaft 5 from above the ground 3, and is a drum around which the horizontal bar 31 is wound. The horizontal bar drum 13 is attached to the upper surface of the turntable 35 at a predetermined interval in the circumferential direction of the turntable 35. The horizontal bar drum 13 is removable from the turntable 35. The rotation axis of each horizontal streak drum 13 is tilted by a predetermined angle with respect to the vertical direction so that the upper end is inside (core material 7 side). The horizontal bar 31 is a strand-shaped reinforcing bar made of a material such as steel, carbon fiber, FRP, or CFRP.

The outer formwork 23 is used as an outer formwork when placing concrete. The outer formwork 23 is attached to the outer guide rail 15 provided on the inner peripheral surface of the side wall 51 of the shaft 5 via the traveling portion 16. The outer formwork 23 can move up and down in the shaft 5 by running the traveling portion 16 along the outer guide rail 15. The traveling portion 16 is removable from the outer guide rail 15.

The inner formwork 25 is used as an inner formwork when placing concrete. The inner formwork 25 is attached to the inner guide rail 17 provided on the outer peripheral surface of the core material 7 via the traveling portion 18. The inner formwork 25 can move up and down in the shaft 5 by running the traveling portion 18 along the inner guide rail 17. The traveling portion 18 is removable from the inner guide rail 17.

The end plate 21 is a plate for fixing the lower ends of each of the vertical bar 29, the horizontal bar 31, and the sheath tube 41. The end plate 21 has a vertical bar fixing portion 211 for fixing the lower end portion of the vertical bar 29, a horizontal bar fixing portion 212 for fixing the lower end portion of the horizontal bar 31, and a sheath tube fixing portion 213 for fixing the lower end portion of the sheath tube 41. The vertical bar fixing portion 211 and the sheath tube fixing portion 213 are, for example, vertical sockets, and the horizontal bar fixing portion 212 is, for example, an oblique socket.

The end plate 21 is connected to the inner guide rail 17 via a slide beam 33. The end plate 21 descends in the shaft 5 by sliding the slide beam 33 along the inner guide rail 17. The slide beam 33 is removable from the inner guide rail 17 and the end plate 21.

The end plate 21 can be fixed to the support block 19 installed on the bottom plate 52 of the shaft 5. The support blocks 19 are installed at predetermined intervals in the circumferential direction of the core material 7. The height of the support block 19 is determined according to the length of the precast concrete member 2 to be manufactured. That is, the length of the manufactured precast concrete member 2 can be adjusted by adjusting the height of the support block 19.

The vertical streak template 27 is a guide for positioning the vertical streak 29 and the sheath pipe 41. The vertical streak template 27 has a vertical streak 29, a vertical streak insertion portion 271 which is a guide hole for inserting the sheath pipe 41, and a sheath pipe insertion portion 273. The diameter of the vertical streak insertion portion 271 and the sheath pipe insertion portion 273 is one size larger than the outer diameter of the vertical streak 29 and the sheath pipe 41. The vertical streak template 27 is fixed to the upper part of the core material 7. The vertical streak template 27 is fixed at a position lower than the vertical streak drum 11 and higher than the horizontal streak drum 13.

(2. Manufacturing method of precast concrete member 2)
(2-1. Installation of manufacturing equipment 1)
In order to manufacture the precast concrete member 2, first, as shown in FIGS. 1 and 2, the foundation concrete 4 and the shaft 5 are constructed on the ground 3, and the core material 7 in the vertical direction is built in the shaft 5. Then, the gantry 9, the outer guide rail 15, the inner guide rail 17, the support block 19, the turntable 35, and the like are arranged.

Further, the vertical streak drum 11 is attached at the position shown in FIGS. 1 and 2 (b), and the horizontal streak drum 13 is attached at the position shown in FIGS. 1 and 2 (c). Further, the end plate 21 is attached to the upper part of the inner guide rail 17 via the slide beam 33 as shown in FIG. 1, and the installation of the manufacturing apparatus 1 is completed. The traveling unit 16 and the outer formwork 23, and the traveling unit 18 and the inner formwork 25 shown in FIG. 1 are removed.

(2-2. Construction of bar arrangement structure 37)
After the manufacturing apparatus 1 is installed in the above state, as shown in FIG. 3, the vertical bar 29 is unwound from the vertical bar drum 11 and hooked on the pulley 12, and the vertical bar insertion portion 271 of the vertical streak template 27 (FIG. 2). (See (c)). Then, the lower end portion of the vertical bar 29 is fixed to the vertical bar fixing portion 211 of the end plate 21. Further, the horizontal bar 31 is unwound from the horizontal bar drum 13, and the lower end portion of the horizontal bar 31 is fixed to the horizontal bar fixing portion 212 of the end plate 21.

FIG. 4 is a diagram showing a state in which the end plate 21 is lowered. After fixing the lower end of the vertical bar 29 and the lower end of the horizontal bar 31 to the end plate 21, the slide beam 33 is slid along the inner guide rail 17 to lower the end plate 21. At the same time, while sending the vertical bar 29 from the vertical bar drum 11 into the shaft 5, the horizontal bar 31 is sent into the shaft 5 while rotating the horizontal bar drum 13 using the turntable 35, whereby the horizontal bar 31 is sent into the vertical bar 29. The bar arrangement structure 37 is constructed by winding the rod at predetermined intervals.

When the end plate 21 descends to the position of the support block 19, the end plate 21 is fixed to the support block 19. As a result, the positions of the lower ends of the bar arrangement structure 37, that is, the lower ends of the vertical bars 29 and the horizontal bars 31 are determined. Then, the slide beam 33 is removed from the end plate 21 and the inner guide rail 17. Since the support blocks 19 are installed at predetermined intervals in the circumferential direction of the core material 7, the support blocks 19 are placed between the support blocks 19 when performing work such as fixing the end plate 21 or removing the slide beam 33. It can be used as a work space.

Further, the vertical bar 29 is separated from the vertical bar drum 11 and the upper end portion is fixed to the vertical bar template 27, and the horizontal bar 31 is separated from the horizontal bar drum 13 and the upper end portion is fixed to the vertical bar 29.

FIG. 5 is a diagram showing a state in which additional vertical bars 29 are arranged. 5 (a) is a diagram showing a cross section taken along the arrow C2-C2 of FIG. 5 (b), and FIG. 5 (b) is a diagram showing a cross section taken along the arrow C1-C1 of FIG. 5 (a).

The bar arrangement structure 37 shown in FIG. 4 incorporates the vertical bars 29 sent out from the eight vertical bar drums 11 shown in FIG. 2 (b). In the step shown in FIG. 5, additional vertical bars 29 are arranged in the bar arrangement structure 37.

To arrange the additional vertical bars 29, as shown in FIG. 5, all the vertical bar drums 11 are removed from the gantry 9, and the horizontal bar drums 13 are removed from the turntable 35. Then, the four vertical streak drums 11 are attached to the turntable 35.

Further, the vertical streak arm 39 is attached to the inner guide rail 17. The vertical bar arm 39 is, for example, an arm protruding from a ring-shaped member, and the protruding arm can be expanded and contracted in the radial direction of the core member 7. Further, in the vertical bar arm 39, a ring-shaped member can be raised and lowered along the inner guide rail 17, and the vertical bar arm 39 can be rotated in the circumferential direction of the core member 7 by a bearing mechanism or the like.

Next, using the turntable 35, the vertical bar drum 11 is rotationally moved in the circumferential direction of the shaft 5, and the vertical bar arm 39 is rotationally moved in the circumferential direction of the core material 7, so that the vertical bar drum 11 and The vertical bar arm 39 is made to correspond to the planned bar arrangement position of the additional vertical bar 29. Then, the additional vertical bar 29 is unwound from the vertical bar drum 11 and passed through the vertical bar insertion portion 271 of the vertical bar template 27, and the lower end portion of the additional vertical bar 29 is gripped by the vertical bar arm 39. After that, the arm 39 for vertical bars is lowered along the inner guide rail 17, and at the same time, additional vertical bars 29 are sent out from above the ground 3 into the shaft 5 and arranged in the bar arrangement structure 37 to provide additional vertical bars. The lower end portion of 29 is fixed to the vertical bar fixing portion 211 (see FIG. 3B) of the end plate 21. After fixing the lower end portion of the additional vertical bar 29 to the end plate 21, the grip on the vertical bar arm 39 is released and the vertical bar arm 39 is raised.

After that, the work of rotating the vertical bar drum 11 and the vertical bar arm 39 to correspond to the position where the additional vertical bar 29 is desired to be arranged and the work of arranging the additional vertical bar 29 are performed as necessary. Repeatedly, a predetermined number of additional vertical bars 29 are arranged.

(2-3. Arrangement of sheath tube 41)
FIG. 6 is a diagram showing a state in which the sheath tube 41 is arranged. When the arrangement of the additional vertical bars 29 is completed, the sheath tube 41 is wound around the vertical bar drum 11 as shown in FIG. 6, and the sheath tube 41 is arranged on the core material 7 side of the vertical bars 29. The position or size of the pulley 12 is adjusted so as to. Further, the overhang length of the arm of the vertical bar arm 39 is adjusted so that the sheath tube 41 can be gripped on the core material 7 side of the vertical bar 29. The sheath tube 41 is made of a flexible material such as polypropylene.

Next, using the turntable 35, the vertical bar drum 11 is rotationally moved in the circumferential direction of the shaft 5, and the vertical bar arm 39 is rotationally moved in the circumferential direction of the core material 7, so that the vertical bar drum 11 and The vertical streak arm 39 is made to correspond to the planned arrangement position of the sheath tube 41. Then, the sheath tube 41 is unwound from the vertical streak drum 11 and passed through the sheath tube insertion portion 273 (see FIG. 5B) of the vertical streak template 27, and the lower end portion of the sheath tube 41 is passed by the vertical streak arm 39. To grasp. After that, the vertical bar arm 39 is lowered along the inner guide rail 17, and at the same time, the sheath pipe 41 is sent out from above the ground 3 into the shaft 5 and arranged in the bar arrangement structure 37, and the lower end portion of the sheath pipe 41 is arranged. Is fixed to the sheath tube fixing portion 213 (see FIG. 3B) of the end plate 21. After fixing the lower end of the sheath tube 41 to the end plate 21, the grip on the vertical bar arm 39 is released and the vertical bar arm 39 is removed from the inner guide rail 17.

(2-4. Mounting the formwork)
7 and 8 are views showing a state in which the outer mold 23 and the inner mold 25 are attached. FIG. 8A shows the positions of the outer formwork 23 and the inner formwork 25 during ascending / descending, and FIG. 8B shows the positions of the outer formwork 23 and a part of the inner formwork 25 at the time of concrete placement. It is a figure which shows the moved state. FIG. 8C is a diagram showing a state in which the entire outer formwork 23 and the inner formwork 25 are moved to the positions at the time of placing concrete, and is a diagram showing a cross section taken along the arrow DD of FIG. In FIG. 8, the traveling portions 16 and 18 are not shown.

After the arrangement of the sheath tube 41 is completed, the outer form 23 is attached to the outer guide rail 15 via the traveling portion 16. Further, the inner formwork 25 is attached to the inner guide rail 17 via the traveling portion 18.

As shown in FIG. 8, the outer mold 23 includes outer molds 23a and 23b. The outer molds 23a and 23b are provided with a taper on the joint surface. Jacks 24a and 24b are provided on the outer peripheral surfaces of the outer formwork 23a and 23b, respectively. Further, the inner mold 25 is composed of the inner molds 25a and 25b. The inner molds 25a and 25b are provided with a taper on the joint surface. Jacks 26a and 26b are provided on the inner peripheral surfaces of the inner formwork 25a and 25b, respectively.

After the outer form 23 and the inner form 25 are attached, the outer form 23 is lowered along the outer guide rail 15 with the jacks 24a, 24b and the jacks 26a, 26b contracted as shown in FIG. 8A. Then, the inner formwork 25 is lowered along the inner guide rail 17.

When the outer formwork 23 and the inner formwork 25 descend to the vicinity of the bottom of the shaft 5, the jack 24a is extended to move the outer formwork 23a inward and the jack 26a is extended to the inside as shown in FIG. 8 (b). The formwork 25a is moved outward. Next, as shown in FIG. 8C, the jack 24b is extended to move the outer formwork 23b inward to make the outer formwork 23 tubular, and the jack 26b is extended to move the inner formwork 25b outward. Move the inner formwork 25 into a tubular shape.

(2-5. Placing concrete 44)
FIG. 9 is a diagram showing a state in which the concrete 44 is placed. After arranging the outer formwork 23 and the inner formwork 25 as shown in FIGS. 7 and 8 (c), preparation for placing concrete is performed. That is, as shown in FIG. 9, the vertical streak drum 11 is removed from the turntable 35, and a concrete hopper 43 having an opening / closing function capable of opening / closing the discharge port is attached to the turntable 35. Then, concrete is poured into the concrete hopper 43 by a truck mixer truck from a truck mount (not shown). Further, the casting pipe 45 is arranged between the outer formwork 23 and the inner formwork 25.

When the preparation for placing concrete is completed, first, the lowermost concrete 44 is placed between the outer formwork 23 and the inner formwork 25 arranged as shown in FIG. 7 from the concrete hopper 43 via the placing pipe 45. Place -1. At this time, by rotating the concrete hopper 43 along the outer circumference of the opening of the shaft 5 using the turntable 35, the casting location by the casting pipe 45 can be changed. Further, by opening and closing the concrete hopper 43, the casting amount at each casting location can be adjusted evenly. The end plate 21 is buried in concrete 44-1.

When the cast concrete 44-1 is hardened, the jack 24b and the jack 26b shown in FIG. 8 are shrunk to move the outer formwork 23b and the inner formwork 25b, and then the jack 24a and the jack 26a are shrunk to the outer formwork 23a. And the inner mold 25a is moved to remove the mold. Then, the outer formwork 23 and the inner formwork 25 are moved one step upward by using the outer guide rail 15 and the inner guide rail 17, and steam 47 is discharged from a steam pipe for curing (not shown) to discharge the concrete 44- after demolding. Perform steam curing of 1.

After that, while moving the outer formwork 23 and the inner formwork 25 step by step from the lower part to the upper part in the shaft 5 by the same procedure as above, the concrete 44-2 between the outer formwork 23 and the inner formwork 25, 44-3, ..., 44-n are sequentially cast and demolded, and cured with steam 47. Since the shaft 5 is formed in the ground 3 and is sealed, there is little temperature change and it is suitable for steam curing. Therefore, the strength of the concrete 44 can be developed at an early stage and the casting can be completed in a short period of time.

(2-6. Construction of tower connection 49)
FIG. 10 is a diagram showing a state in which the tower connecting portion 49 is constructed. After placing the top concrete 44-n, the reinforcing bars and formwork are assembled above the concrete 44-n and the concrete is placed to construct the tower connection part 49 for connecting to the tower of the offshore wind turbine. ..

(2-7. Completion of precast concrete member 2)
FIG. 11 is a diagram showing a state in which a tension force is introduced into the precast concrete member 2. When the concrete of the tower connecting portion 49 is hardened, the tension material 42 is inserted into the sheath pipe 41 as shown in FIG. 11, and the lower end portion is fixed to the end plate 21. The lower end of the tension member 42 may be automatically fixed to the end plate 21, or an operator may enter between the support blocks 19 to fix the lower end of the tension member 42 to the end plate 21. Good. After that, the tension member 42 is strained to fix the upper end portion to the tower connecting portion 49.

After the tension member 42 is fixed, ancillary equipment (not shown) such as a fall prevention handrail is attached to the tower connecting portion 49 to complete the precast concrete member 2. Then, the top fixing beam 92 is removed from the gantry 9.

(2-8. Pulling out the precast concrete member 2)
FIG. 12 is a diagram showing a state in which the precast concrete member 2 is pulled out from the shaft 5. After removing the top fixing beam 92 from the gantry 9, the precast concrete member 2 is pulled out from the shaft 5 by using a large crane vessel 50 berthed on the quay near the ground 3.

As described above, according to the present embodiment, by using the shaft 5 constructed on the ground 3 as the manufacturing yard, the precast concrete member 2 can be manufactured in a short period of time using a limited space. Further, the outer form 23 and the inner form 25 are formed by using the outer guide rail 15 provided on the inner peripheral surface of the shaft 5 and the inner guide rail 17 provided on the outer peripheral surface of the core material 7 built in the shaft 5. By placing the concrete 44 while moving it step by step from the lower part to the upper part of the shaft 5, the precast concrete member 2 having a cylindrical cross section can be manufactured with high accuracy.

In the present embodiment, by using the end plate 21, the lower end of the vertical bar 29, the lower end of the horizontal bar 31, and the lower end of the tension member 42 are securely fixed to prevent misalignment, and the precast concrete member 2 The bottom can be reinforced. Further, by using the turntable 35, the horizontal bar drum 13 can be smoothly rotated and the horizontal bar 31 can be wound around the vertical bar 29.

In the present embodiment, the horizontal bar drum 13 is removed from the turntable 35, the vertical bar drum 11 is attached, and the vertical bar drum 11 is rotationally moved along the outer circumference of the opening of the shaft 5 to be one with the horizontal bar 31. After constructing the bar arrangement structure 37 including the vertical bars 29 of the portion, additional vertical bars 29 can be sent out into the shaft 5 from a desired position to arrange the bars. Therefore, the bar arrangement structure 37 can be constructed without arranging a large number of vertical bar drums 11 overcrowded.

In the present embodiment, the thickness of the precast concrete member 2 can be reduced and the weight can be reduced by arranging the sheath pipe 41 and the tension member 42 to introduce the tension force. Further, by constructing the tower connecting portion 49 for connecting to the tower of the offshore wind turbine, it is possible to easily manufacture the monopile foundation of the offshore wind turbine to which the tower can be directly connected.

Although preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that a person skilled in the art can come up with various modifications or modifications within the scope of the technical idea disclosed in the present application, and these also naturally belong to the technical scope of the present invention. Understood.

In the present embodiment, the tower connecting portion 49 is constructed at the upper end of the precast concrete member 2, but the tower connecting portion 49 is not essential. Further, the location condition of the ground 3 is not limited to the back surface of the quay, and the use of the precast concrete member is not limited to the monopile foundation. It is desirable that the shaft 5 is constructed on the ground 3 near the site where a cylindrical precast concrete member is used. For example, the shaft 5 is constructed on the ground 3 in the inland area to construct a cylindrical precast concrete pile. You may.

In the present embodiment, the vertical bar drum 11 is replaced from the gantry 9 to the turntable 35, and additional vertical bars 29 are arranged in the bar arrangement structure 37. However, when the vertical bars 29 are not added, the vertical bar drum 11 There is no need to replace it. Further, in the bar arrangement structure 37, the vertical bars 29 are arranged on a single circumference, but by adjusting the position of the pulley 12 and the gripping position by the vertical bar arm 39, the vertical bars 29 are made into a double or more circle. It may be placed on the circumference.

In the present embodiment, the sheath pipe 41 and the tension member 42 are provided to manufacture the precast prestressed concrete member, but the sheath pipe 41 and the tension member 42 may not be provided to manufacture the precast reinforced concrete member.

In the present embodiment, after the reinforcing bar arrangement structure 37 is constructed, the outer form 23 and the inner form 25 are attached to the outer guide rail 15 and the inner guide rail 17 from above the shaft 5 and lowered. The mounting time of the inner form 25 is not limited to this. For example, the outer formwork 23 and the inner formwork 25 may be attached at the same time as the outer guide rail 15 and the inner guide rail 17 are installed. In this case, a space may be provided below the support block 19 and the outer formwork 23 and the inner formwork 25 may be stored in this space until the start of concrete placement.

1 ………… Manufacturing equipment 2 ………… Precast concrete member 3 ………… Ground 4 ………… Foundation concrete 5 ………… Vertical shaft 7 ………… Core material 9 ………… Stand 11 ………… Vertical bar drum 12 ……… Crane 13 ……… Horizontal muscle drum 15 ……… Outer guide rails 16, 18 ……… Running part 17 ……… Inner guide rail 19 ……… Support block 21 ……… End plates 23, 23a, 23b ……… Outer formwork 24a, 24b ……… Jack 25, 25a, 25b ……… Inner formwork 26a, 26b ……… Jack 27 ……… Vertical line template 29 ……… Vertical line 31 ……… Horizontal line 33 ………… Slide beam 35 ………… Turntable 37 ………… Reinforcing structure 39 ………… Vertical bar arm 41 ………… Sheath pipe 42 ………… Tension material 43 ………… Concrete hopper 44, 44-1 , 44-2, 44-3, 44-n ………… Concrete 45 ………… Casting pipe 47 ………… Steam 49 ………… Tower connection 50 ………… Crane ship 51 ………… Side wall 52 ………… Bottom plate 91 ………… Main body 92 ………… Top end fixing beam 211 ………… Vertical bar fixing part 212 ………… Horizontal bar fixing part 213 ………… Sheath tube fixing part 271 ………… Vertical bar insertion part 273 ………… Sheath Tube insertion part

Claims (12)

A method for manufacturing cylindrical precast concrete members.
Step a of constructing a shaft on the ground and building a vertical core material in the shaft,
A step b of constructing a bar arrangement structure in the shaft by winding the horizontal bars around the vertical bars while sending the vertical bars and the horizontal bars from the ground into the shaft.
Step c of attaching the outer formwork to the outer guide rail provided on the inner peripheral surface of the shaft and attaching the inner formwork to the inner guide rail provided on the outer peripheral surface of the core material.
While moving the outer formwork and the inner formwork from the lower part to the upper part in the shaft by using the outer guide rail and the inner guide rail, concrete is cast between the outer formwork and the inner formwork. Step d to set up
Step e of pulling out the precast concrete member from the shaft,
A method for manufacturing a precast concrete member, which comprises the above. In the step b, the end plate is lowered with the lower end of the vertical bar and the lower end of the horizontal bar fixed to the end plate, and the end plate is fixed to the support block provided in the lower part of the shaft. The method for manufacturing a precast concrete member according to claim 1, wherein the precast concrete member is manufactured. 2. A second aspect of the present invention, wherein an additional vertical bar is sent into the shaft from above the ground and the lower end portion of the additional vertical bar is fixed to the end plate between the step b and the step c. The method for manufacturing a precast concrete member according to the description. Between the step b and the step c, a sheath pipe is sent into the shaft from above the ground, and the lower end portion of the sheath pipe is fixed to the end plate.
The precast concrete product according to claim 2 or 3, wherein a tension material is inserted into the sheath tube between the step d and the step e to fix the tension material to the end plate. Manufacturing method of parts. The method for manufacturing a precast concrete member according to any one of claims 1 to 4, wherein in the step d, the outer formwork and the concrete from which the inner formwork has been removed are steam-cured. The precast concrete member is the monopile foundation of the offshore wind turbine.
Claims 1 to 1, wherein a tower connecting portion for connecting to the tower of the offshore windmill is constructed between the step d and the step e above the concrete placed in the step d. 5. The method for manufacturing a precast concrete member according to any one of 5. A device for manufacturing cylindrical precast concrete members.
A shaft with a predetermined depth and
A core material installed vertically in the shaft and
A vertical bar feeding device for feeding vertical bars from above the ground into the shaft, and
A horizontal bar feeding device for feeding horizontal bars from above the ground into the shaft, and
A rotating device that rotates the horizontal bar feeding device along the outer circumference of the opening on the ground surface of the shaft, and
An outer formwork that can be raised and lowered along the outer guide rail provided on the inner peripheral surface of the shaft,
An inner formwork that can be raised and lowered along the inner guide rail provided on the outer peripheral surface of the core material,
A device for manufacturing a precast concrete member, which comprises. Further equipped with a pedestal provided on the ground so as to straddle the shaft,
The upper end of the core material is fixed to the frame,
The precast concrete member manufacturing apparatus according to claim 7, wherein the vertical streak feeding device is attached to the gantry. The precast concrete member manufacturing apparatus according to claim 7 or 8, wherein the rotating device can be attached with the vertical bar feeding device by removing the horizontal bar feeding device. The precast concrete member manufacturing apparatus according to any one of claims 7 to 9, wherein the rotating device is a turntable. The precast concrete member manufacturing apparatus according to any one of claims 7 to 10, wherein the rotating device is provided with a concrete hopper having an opening / closing function. The apparatus for manufacturing a precast concrete member according to any one of claims 7 to 11, wherein the core material is a steel pipe.

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