Method for constructing a superstructure on water

Abstract

To provide a method for efficiently constructing an upper structure on the water without performing complicated work below a precast block installed on a support erected on the water bottom ground.SOLUTION: The closed frame body 8 is temporarily arranged by a plurality of hanging position changing means 9 in a state of being externally fitted to the side L1 of the predetermined height of the support body 50. The precast block 2 is temporarily fixed to the support body 50 in a state where the support body 50 is loosely inserted into the through-hole 3 of the precast block 2, the closing frame body 8 is raised by operating each of the suspension position changing means 9 from above the precast block 2, the closing frame body 8 is brought into contact with the bottom surface of the precast block 2, and the gap between the outer peripheral surface of the support body 50 and the lower end of the through-hole 3 is closed by the closing frame body 8. The upper work 1 is fixed to the upper part of the support body 50 by filling and solidifying a filling material 30 between the outer peripheral surface of the support body 50 and the inner peripheral surface of the through-hole 3.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a method for constructing a superstructure above water, and more specifically, to a method for constructing a superstructure above water that enables efficient construction of a superstructure above water without performing complicated work below precast blocks installed on supports such as piles and sheet piles erected on the bottom ground. [Background technology]

[0002] One method for constructing superstructures above water, such as piers and revetments, supported by supports such as piles and sheet piles erected on the waterbed is to install formwork after reinforcing bars are placed above or underwater, and then pour ready-mixed concrete into the formwork at the construction site and allow it to harden. This type of superstructure construction method requires the installation of temporary scaffolding and shoring above or underwater, assembling the reinforcing bars, and then installing formwork and pouring concrete, which requires a lot of tedious work above water, and therefore limits the improvement in construction efficiency.

[0003] Therefore, a construction method for an overwater structure (superstructure) has been proposed in which a precast concrete slab with pile holes for the piles is formed on land, the precast concrete slab is fixed to the piles with the heads of the piles loosely inserted into the pile holes, and scaffolding is attached around the outside of the precast concrete slab (see, for example, Patent Document 1). In this construction method, the gaps between the pile holes in the precast concrete slab and the outer periphery of the piles are sealed with a leak-proof plate installed below the precast concrete slab, and the gaps are filled with non-shrinkage mortar to secure the precast concrete slab to the pile heads. However, in the construction method proposed in Patent Document 1, the work of sealing the gaps between the pile holes in the precast concrete slab and the outer periphery of the piles with the leak-proof plate must be performed from below the precast concrete slab installed on the piles, which requires the installation of an overwater scaffolding and the entry of workers such as divers under the precast concrete slab to perform complicated work. Therefore, there is room for improvement in the construction efficiency and safety of workers in constructing an overwater superstructure. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-107631 Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is to provide a method for constructing a superstructure above water that enables efficient construction of a superstructure above water without performing complicated work below precast blocks installed on supports such as piles or sheet piles erected on the waterbed ground. [Means for solving the problem]

[0006] In order to achieve the above object, the method for constructing a superstructure on water of the present invention is a method for constructing a superstructure on water that is fixed to the top of a support erected on the bottom ground, in which a blocking frame body extending outward from the outer circumferential surface of the support in a plan view is fitted onto the support in a state in which it can be moved up and down, the lower ends of multiple hanging position change means are respectively connected to the top of the blocking frame body, and the engaging portions provided on each of the hanging position change means are engaged with the top of the support, so that the blocking frame body is temporarily positioned at a predetermined height on the support by the multiple hanging position change means, and a precast block having through holes that pass through in the vertical direction and through which the support can be loosely inserted is moved downward from above the support, and the precast block is attached to the support in a state in which the support is loosely inserted into the through holes. The method is characterized in that the block blocks are temporarily fixed, and the engaging portions provided on each of the hanging position change means are engaged with either the upper part of the support body or the engaged portion provided on the inner periphery of the through hole of the precast block.By operating each of the hanging position change means from above the precast block, the blocking frame body is raised from the specified height relative to the support body, so that the upper surface of the blocking frame body abuts against the bottom surface of the precast block, and the blocking frame body seals the gap between the outer surface of the support body and the lower end of the through hole.By filling the space between the outer surface of the support body and the inner surface of the through hole and solidifying it, the superstructure, which is integrated with the precast block and the solidified filling material, is fixed to the top of the support. [Effects of the Invention]

[0007] According to the present invention, a closure frame is temporarily positioned by fitting it to the support at a predetermined height using multiple suspension position change devices. Then, the precast block is temporarily fixed to the support while the support is loosely inserted into the through-hole of the precast block, thereby completing the installation of the precast block on the support. Next, by operating each suspension position change device from above the precast block, the closure frame is raised from the predetermined height relative to the support, so that the upper surface of the closure frame abuts against the bottom surface of the precast block. This allows the gap between the outer surface of the support and the lower end of the through-hole to be sealed without requiring any tedious work below the precast block installed on the support. Then, by filling and solidifying a fill material between the outer surface of the support and the inner surface of the through-hole of the precast block, it becomes possible to efficiently construct a superstructure above water without requiring any tedious work below the precast block installed on the support. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram illustrating a side view of a superstructure constructed on top of a support using the method for constructing a superstructure on water of the present invention. [Figure 2] This is an explanatory diagram showing a cross-sectional view of a closure frame body temporarily positioned at a predetermined height on the support body by the hanging position change means, and a precast block before being installed on the support body. [Figure 3] This is an explanatory diagram showing a plan view of a closure frame body temporarily positioned at a predetermined height on the support body using a hanging position change means, and a precast block before being installed on the support body. [Figure 4] 4 is an explanatory diagram illustrating an enlarged cross-sectional view of the hanging position changing means of FIG. 2 and FIG. 3. FIG. [Figure 5] 4 is an explanatory diagram illustrating an enlarged plan view of the hanging position changing means of FIG. 2 and FIG. 3. FIG. [Figure 6] 4 is an explanatory diagram illustrating a cross-sectional view of the state in which the precast block is installed on the support from the state shown in FIGS. 2 and 3. FIG. [Figure 7] FIG. 7 is a view taken along the arrow A in FIG. 6. [Figure 8]This is an explanatory diagram showing a cross-sectional view of the state in which the blocking frame body is raised from a predetermined height relative to the support body from the state shown in Figures 6 and 7, and the upper surface of the blocking frame body is abutted against the bottom surface of the precast block. [Figure 9] 10 is an explanatory diagram illustrating an enlarged cross-sectional view of a state in which a suspending member constituting a suspending position changing means is moved upward using an impact driver and a fitting tool. FIG. [Figure 10] 9 is an explanatory diagram illustrating a cross-sectional view of the state shown in FIG. 8 in which a fill material is filled between the outer peripheral surface of the support body and the inner peripheral surface of the through hole of the precast block and solidified. [Figure 11] FIG. 11 is a view taken along the arrow B in FIG. [Figure 12] This is an explanatory diagram illustrating a cross-sectional view of a blocking frame body temporarily positioned at a predetermined height on the support body using a hanging position change means in another embodiment, and a precast block before being installed on the support body. [Figure 13] 13 is an explanatory diagram illustrating an enlarged cross-sectional view of the hanging position change means of FIG. 12.

[0033] FIG. [Figure 14] 13 is an explanatory diagram illustrating a cross-sectional view of the state in which the precast block is installed on the support from the state shown in FIG. 12. FIG. [Figure 15] This is an explanatory diagram showing a cross-sectional view of the state in which the closure frame body is raised from a predetermined height relative to the support body from the state shown in Figure 14, and the upper surface of the closure frame body is abutted against the bottom surface of the precast block. [Figure 16] This is an explanatory diagram illustrating another embodiment of the method for constructing an above-water superstructure of the present invention, and is a cross-sectional view illustrating a blocking frame body temporarily positioned at a predetermined height on the support by a hanging position change means, and a precast block before being installed on the support. [Figure 17] 17 is an explanatory diagram illustrating a cross-sectional view of the state in which the precast block is installed on the support from the state shown in FIG. 16. FIG. [Figure 18] This is an explanatory diagram showing, in cross section, the state in which the connection between the upper part of the blocking frame body and the upper part of the support body by multiple hanging position change means has been released from the state shown in Figure 17, and the upper part of the blocking frame body and the precast block have been connected by multiple hanging position change means. [Figure 19]This is an explanatory diagram showing a cross-sectional view of the state in which the closure frame body is raised from a predetermined height relative to the support body from the state shown in Figure 18, and the upper surface of the closure frame body is abutted against the bottom surface of the precast block. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, the method for constructing a superstructure above water of the present invention will be described based on the embodiment shown in the drawings.

[0010] As illustrated in Fig. 1, the present invention is a method for constructing a superstructure 1 above water that is fixed to the top of supports 50 cast into the waterbed ground WB. Examples of supports 50 include piles such as steel pipe piles and concrete piles, and sheet piles such as steel pipe sheet piles. Examples of superstructure 1 include piers and revetments. In the embodiment illustrated in Figs. 1 to 11 described below, the supports 50 are steel pipe piles, and a concrete superstructure 1 is constructed on top of the steel pipe piles.

[0011] This embodiment illustrates the construction of a superstructure 1 fixed to the top of one support 50, but this construction method can also be used to construct a superstructure 1 fixed to the top of two or more supports 50. The superstructure 1 above water constructed using this construction method is not limited to a superstructure 1 that is always located above the water surface level WL, but also includes a superstructure 1 that is temporarily partially submerged in water due to tidal fluctuations, etc.

[0012] As illustrated in Figures 2 and 3, in this construction method, a superstructure 1 is constructed using precast blocks 2, a closure frame 8, and a plurality of lifting position change means 9. The precast blocks 2 are formed, for example, from precast concrete, prestressed concrete, resin, etc., and are fabricated in advance on land or on a ship. The precast blocks 2 may be, for example, a reinforced concrete (steel-reinforced concrete) structure in which reinforcing bars (or steel frames) are embedded in precast concrete or prestressed concrete, or a structure in which reinforcing bars, etc., are not embedded in precast concrete or prestressed concrete.

[0013] The precast block 2 has a through hole 3 that passes through vertically, into which the support body 50 can be loosely inserted. In this embodiment, the through hole 3 is formed in one location in the center of the precast block 2. The precast block 2 of this embodiment is composed of a precast concrete block body 4 in which the through hole 3 is formed, a sheath pipe 5 that is fitted into the through hole 3 and extends vertically, a beam member 6 that protrudes inside the through hole 3 in a plan view, and a hanging hardware 7.

[0014] In this embodiment, the block body 4 has an outer shape formed in a rectangular parallelepiped shape, but the outer shape of the block body 4 is not limited to a rectangular parallelepiped shape and can be other shapes. The sheath pipe 5 can be provided arbitrarily in the precast block 2, and a precast block 2 without a sheath pipe 5 can also be used. The sheath pipe 5 can be a resin tubular member formed from fiber-reinforced plastic (FRP) or a metal tubular member such as a steel pipe. In this embodiment, the upper end of the sheath pipe 5 is located lower than the upper end surface of the precast block 2. In other words, there is a portion above the through hole 3 in the precast block 2 where the sheath pipe 5 is not provided.

[0015] In the present invention, in the area where the sheath pipe 5 of the precast block 2 is provided, the inner peripheral surface of the sheath pipe 5 is the inner peripheral surface of the through hole 3. In the area where the sheath pipe 5 of the precast block 2 is not provided, the concrete surface on the inside of the through hole 3 is the inner peripheral surface of the through hole 3.

[0016] The inner dimensions of the through hole 3 (sheath tube 5) are set to dimensions that allow loose insertion of the support 50. The inner dimensions of the through hole 3 are preferably set to dimensions that leave a gap (clearance) of, for example, 5 cm or more and 25 cm or less, more preferably 10 cm or more and 15 cm or less, between the inner circumferential surface of the through hole 3 and the outer circumferential surface of the support 50 when the support 50 is inserted into the through hole 3 with the center position of the through hole 3 and the center position of the support 50 aligned in a plan view.

[0017] The beam members 6 are made of steel such as H-shaped steel or channel steel, or rod-shaped members made of resin. In this embodiment, H-shaped steel is used as the beam members 6. The beam members 6 extend horizontally, and in plan view, the beam members 6 protrude into the inside of the through hole 3 (sheath pipe 5). At least a portion of the beam members 6 extends to the outside of the through hole 3 in plan view. As illustrated in Figures 2 and 3, in this embodiment, the beam members 6 are arranged so as to cross each other in a plan view, and the beam members 6 span across the through hole 3.

[0018] As illustrated in FIG. 2, the beam members 6 are arranged, for example, above the sheath pipes 5 or on top of the sheath pipes 5. In this embodiment, grooves into which the respective beam members 6 are fitted are formed in the upper part of the sheath pipes 5, and the beam members 6 are fitted into the grooves. For example, the beam members 6 can also be placed on the sheath pipes 5. The portions of the beam members 6 located inside the through holes 3 are exposed, and the portions of the beam members 6 located outside the through holes 3 are embedded in the precast concrete that constitutes the block body 4. The upper ends of the beam members 6 are arranged at a position lower than the upper end surface of the precast block 2.

[0019] The upper part of the block body 4 is provided with a plurality of lifting fittings 7 that are used when lifting the precast blocks 2 with a crane. In this embodiment, a lifting fitting 7 is provided at each of the four corners of the upper part of the block body 4. The lower part of each lifting fitting 7 is embedded in the precast concrete that makes up the block body 4, and the lifting fittings 7 are integrated into the block body 4. The lifting fittings 7 can be optionally provided on the precast blocks 2. If the precast blocks 2 are to be lifted using a method that does not use the lifting fittings 7, a precast block 2 without the lifting fittings 7 can also be used. Although not shown in this embodiment, if accessories such as mooring bollards are to be provided on the superstructure 1, the accessories such as mooring bollards can also be integrated into the precast blocks 2 (block body 4).

[0020] In this embodiment, a groove 4a that is annular in plan view is provided on the outside of the upper end of the sleeve tube 5 in the block body 4. The bottom surface of the groove 4a is set at a position lower than the upper end of the sleeve tube 5, and the upper end of the sleeve tube 5 protrudes above the bottom surface of the groove 4a.

[0021] As illustrated in FIGS. 2 and 3 , the closure frame 8 is annular in plan view and fitted onto the support 50 so as to be movable up and down. The inner diameter of the insertion hole inside the closure frame 8 is set to be substantially the same as the outer diameter of the outer peripheral surface of the support 50. The closure frame 8 extends outward from the outer peripheral surface of the support 50 in plan view. The closure frame 8 extends outward beyond the through-hole 3 in the precast block 2 in plan view. The closure frame 8 is formed of a plate-like member made of, for example, metal, resin, or wood. The thickness of the closure frame 8 can be determined appropriately depending on the material of the closure frame 8 and the size of the superstructure 1, but is set to, for example, 3 mm or more and 30 mm or less. In this embodiment, the closure frame 8 has a circular outer shape in plan view, but the outer shape of the closure frame 8 in plan view can also be other shapes, such as a polygonal shape.

[0022] As shown in FIG. 3 , the closure frame 8 of this embodiment is composed of four divided members obtained by radially dividing a circular plate-like member into four parts in a plan view. Each divided member is composed of a fan-shaped plate-like member with a central angle of 90 degrees in a plan view, and the closure frame 8 is formed by closely contacting the ends of adjacent divided members so that they face each other. For example, the closure frame 8 can be configured such that each divided member is composed of a fan-shaped plate-like member with a central angle of 90 degrees or more in a plan view, and a step is provided between adjacent divided members so that the ends of adjacent divided members overlap each other vertically. The number and shape of the divided members constituting the closure frame 8 are not particularly limited. For example, the closure frame 8 can be configured with three or fewer divided members or five or more divided members. For example, the closure frame 8 can be configured with a single plate-like member that is annular in a plan view.

[0023] In this embodiment, an intervening member 8a is provided on the inner surface of the closure frame 8, which abuts against the outer peripheral surface of the support 50, to improve adhesion between the outer peripheral surface of the support 50 and the inner surface of the closure frame 8. The intervening member 8a, which improves adhesion between the outer peripheral surface of the support 50 and the inner surface of the closure frame 8, can also be provided on the outer peripheral surface of the support 50, for example. The intervening member 8a can be made of, for example, an elastic material such as rubber or a flexible resin. It is preferable to use a highly elastic rubber material, such as that used in general packing, for the intervening member 8a. The intervening member 8a may be either solid or hollow, but a solid body is more preferable. It is preferable that the dimensions (outer diameter) of the outer peripheral surface of the support 50 and the dimensions (inner diameter) of the inner peripheral surface of the intervening member 8a are substantially the same.

[0024] The width (radial thickness) of the intervening member 8a may be set, for example, to 5 mm or more and 15 mm or less, more preferably 8 mm or more and 12 mm or less. The intervening member 8a may also be made of a material, such as a fluororesin, that reduces friction between the outer peripheral surface of the support body 50 and the inner surface of the closure frame 8. One method for reducing friction between the outer peripheral surface of the support body 50 and the inner surface of the closure frame 8 is to apply a lubricant to the outer peripheral surface of the support body 50 or the inner surface of the closure frame 8. For example, wheels or bearings may be provided on the inner surface of the closure frame 8 as a material that reduces friction between the outer peripheral surface of the support body 50 and the inner surface of the closure frame 8. The intervening member 8a may also be made of a material that does not have the effect of reducing friction between the outer peripheral surface of the support body 50 and the inner surface of the closure frame 8.

[0025] 2 and 3, in this construction method, a plurality of hanging position changing means 9 are used as a means for suspending the closure frame body 8 relative to the support body 50. The lower end of the hanging position changing means 9 is connected to the upper part of the closure frame body 8. The hanging position changing means 9 is provided with an engaging portion 12 that can engage with the upper part of the support body 50. The hanging position changing means 9 in this embodiment is composed of a hanging member 10 whose lower end is connected to the upper part of the closure frame body 8 and extends in the vertical direction, and a holding jig 11 that is provided midway on the hanging member 10 and holds the hanging member 10 in a state where it can move relatively in the vertical direction, and the engaging portion 12 is attached to the holding jig 11.

[0026] As illustrated in Figures 4 and 5, the hanging member 10 of this embodiment is composed of a metal rod-shaped member 10a having a threaded groove. The rod-shaped member 10a can be, for example, a known separator used in constructing concrete forms. The hanging member 10 (rod-shaped member 10a) extends upward from the upper portion of the closure frame 8. In this embodiment, the upper portion of the closure frame 8 and the lower end of the hanging member 10 are connected via a connecting member 13. The connecting member 13 in this embodiment is configured to change the angle (direction) at which the hanging member 10 extends relative to the closure frame 8. The connecting member 13, which changes the angle (direction) at which the hanging member 10 extends, can be formed, for example, from an elastic material such as rubber or a flexible resin. The method for connecting the lower end of the hanging member 10 to the upper portion of the closure frame 8 is not particularly limited. For example, the upper portion of the closure frame 8 and the lower end of the hanging member 10 can be connected via a connecting device that changes the angle at which the hanging member 10 extends. For example, the lower end of the hanging member 10 can be fixed to the upper part of the closure frame 8 by welding or the like.

[0027] The holding jig 11 of this embodiment is composed of a metal insert 11a through which the rod-shaped member 10a is inserted, and a nut 11b that is placed on the metal insert 11a and screws into the threads of the rod-shaped member 10a. The metal insert 11a is composed of a cylindrical metal piece with a through hole that is approximately the same size as the diameter of the rod-shaped member 10a. No threads are formed on the inner surface of the insertion hole of the metal insert 11a. The metal insert 11a and the nut 11b are not joined. In this embodiment, a washer 11c through which the rod-shaped member 10a is inserted is interposed between the upper end of the metal insert 11a and the lower end of the nut 11b. The washer 11c can be provided as needed.

[0028] In this embodiment, the engaging portion 12 is configured with a hook 12a that can be hooked onto the upper portion (edge ​​of the upper end) of the support body 50 (steel pipe pile). The hook 12a can be formed, for example, by bending a reinforcing bar into a substantially U-shape. The engaging portion 12 (hook 12a) is joined to the side of the holding jig 11 (insertion fitting 11a). By engaging the engaging portion 12 with the upper portion of the support body 50, the holding jig 11 (insertion fitting 11a) can be fixed to the upper portion of the support body 50. The closure frame 8 can be suspended from the support body 50 by the holding jig 11 (insertion fitting 11a) fixed to the upper portion of the support body 50 via the engaging portion 12 and the hanging member 10 (rod-shaped member 10a) supported by the holding jig 11 (insertion fitting 11a, nut 11b).

[0029] As illustrated in FIG. 3, in this embodiment, a plurality of hanging position changing means 9 are arranged at intervals so as to surround the outside of the insertion hole of the closure frame body 8 in a plan view. The hanging position changing means 9 are arranged at a plurality of locations on each of the divided members that make up the closure frame body 8. It is preferable to arrange the plurality of hanging position changing means 9 so that the spacing between adjacent hanging position changing means 9 (the lower ends of the hanging members 10) is equal when the closure frame body 8 is formed. As illustrated in FIG. 3, in this embodiment, the hanging position changing means 9 are provided at 12 locations on the closure frame body 8, but the number and arrangement of the hanging position changing means 9 provided on the closure frame body 8 can be determined appropriately depending on the size, weight, etc. of the closure frame body 8.

[0030] In this embodiment, a protrusion 8b extending toward the adjacent divided member is provided on the underside of each divided member constituting the closure frame 8, and when the closure frame 8 is formed by four divided members suspended by a plurality of suspension position changing means 9, the protrusions 8b provided on each divided member allow adjacent divided members to support each other's weight. The protrusions 8b can be provided arbitrarily as needed.

[0031] As illustrated in FIGS. 2 and 3 , this embodiment further uses a plurality of auxiliary lifting means 14 as a means for suspending the closure frame 8 relative to the precast block 2. The auxiliary lifting means 14 in this embodiment is composed of a connecting member 15 whose lower end is connected to the upper part of the closure frame 8 and extends in the vertical direction, and a connecting jig 16 that engages with the sheath tube 5 to fix the upper part of the connecting member 15. The connecting jig 16 is provided with an engaging portion 17 that can engage with an engaged portion 3b provided on the inner periphery 3a of the through hole 3 in the precast block 2. In this embodiment, the upper end of the sheath tube 5 is the engaged portion 3b, and the engaging portion 17 is configured to be engageable with the upper end of the sheath tube 5. FIGS. 2 and 3 show the connecting member 15 and the connecting jig 16 with the engaging portion 17 separated from each other.

[0032] In this embodiment, the connecting member 15 and the connecting jig 16 that constitute the auxiliary suspension means 14 are respectively made of the same material as the suspension member 10 and the holding jig 11 that constitute the suspension position changing means 9. Furthermore, the engaging portion 17 provided on the auxiliary suspension means 14 is made of the same material as the engaging portion 12 provided on the suspension position changing means 9. Like the suspension member 10, the connecting member 15 is made of a metal rod-shaped member 15a that is provided with a thread. The connecting member 15 (rod-shaped member 15a) extends upward from the upper portion of the closure frame 8. In this embodiment, the upper portion of the closure frame 8 and the lower end of the connecting member 15 are connected via a connecting portion 18. The connecting portion 18 in this embodiment is configured to change the angle (direction) at which the connecting member 15 extends relative to the closure frame 8. The connecting portion 18 that changes the angle (direction) at which the connecting member 15 extends can be formed, for example, from an elastic material such as rubber or a flexible resin. The method for connecting the lower end of the connecting member 15 to the upper part of the closure frame 8 is not particularly limited, and for example, the upper part of the closure frame 8 and the lower end of the connecting member 15 can be connected via a connector that can change the angle at which the connecting member 15 extends. For example, the lower end of the connecting member 15 can be fixed to the upper part of the closure frame 8 by welding or the like.

[0033] The connecting jig 16 of this embodiment is configured to hold the connecting member 15 in a state where it can move relative to the rod-shaped member 15 in the vertical direction. Similar to the holding jig 11, the connecting jig 16 of this embodiment includes a metal insert 16a through which the rod-shaped member 15a can be inserted, and a nut 16b arranged on the metal insert 16a and threaded into the thread groove of the rod-shaped member 15a. The metal insert 16a is a cylindrical metal piece with a through-hole of approximately the same dimensions as the diameter of the rod-shaped member 15a. No thread grooves are formed on the inner surface of the insertion hole of the metal insert 16a. The metal insert 16a and the nut 16b are not joined. In this embodiment, a washer 16c through which the rod-shaped member 15a can be inserted is interposed between the upper end of the metal insert 16a and the lower end of the nut 16b. The washer 16c can be provided as needed.

[0034] The engaging portion 17 in this embodiment is configured with a hook 17a that can be hooked onto the upper end (edge) of the sleeve tube 5. In this embodiment, a groove 4a is provided on the outside of the sleeve tube 5, allowing the engaging portion 17 to engage with the upper end (edge) of the sleeve tube 5 that constitutes the engaged portion 3b. The engaging portion 17 (hook 17a) is joined to the side of the connecting jig 16 (insertion metal fitting 16a). By engaging the engaging portion 17 (hook 17a) with the engaged portion 3b (upper end of the sleeve tube 5) provided on the inner periphery 3a of the through hole 3 in the precast block 2, the connecting jig 16 (insertion metal fitting 16a) can be fixed to the precast block 2.

[0035] As illustrated in Figures 2 and 3, in this embodiment, connecting members 15 and connecting portions 18 constituting multiple auxiliary lifting means 14 are arranged to surround the outside of the insertion holes of the closure frame 8 in a plan view. In a plan view, the multiple auxiliary lifting means 14 (connecting members 15) are arranged outside the multiple suspension position changing means 9 (suspending members 10). Connecting members 15 are arranged at multiple locations on each of the divided members constituting the closure frame 8. It is preferable to arrange the multiple auxiliary lifting means 14 so that the spacing between adjacent auxiliary lifting means 14 (lower ends of connecting members 15) is equal when the closure frame 8 is formed. In this embodiment, auxiliary lifting means 14 are provided at 12 locations on the closure frame 8, but the number and arrangement of auxiliary lifting means 14 on the closure frame 8 can be determined appropriately depending on the size, weight, etc. of the closure frame 8. The auxiliary lifting means 14 can be provided as needed.

[0036] The specific work procedures for the method of constructing the superstructure 1 of the present invention will be described below.

[0037] 2 and 3, the precast blocks 2 having the above-described configuration, the closure frame 8, and the components that make up the lifting position change means 9 are fabricated in advance on land or on a ship to match the size of the support body 50 that will construct the superstructure 1. Then, the precast blocks 2, the closure frame 8, and the components that make up the lifting position change means 9 and the engagement part 12 are transported by a work vessel equipped with a crane to the construction waters where the support body 50 is erected. When the lifting auxiliary means 14 is used, the components that make up the lifting auxiliary means 14 and the engagement part 17 are also fabricated in advance on land or on a ship, and then transported to the construction waters.

[0038] In this embodiment, the hoisting position changing means 9 are disposed at multiple locations on the upper portion of the divided members that make up the closure frame 8, such as on a work vessel. Specifically, the lower ends of the hoisting members 10 (rod-shaped members 10a) that make up each of the hoisting position changing means 9 are connected to the upper portions of the divided members that make up the closure frame 8 by connecting portions 13. Then, the insertion metal fitting 11a that makes up the holding jig 11 is inserted into the upper portion of the rod-shaped member 10a that is the hoisting member 10, and a washer 11c is placed on the insertion metal fitting 11a. Next, the nut 11b is threaded onto the upper end of the rod-shaped member 10a, and the nut 11b is rotated relative to the rod-shaped member 10a so that the nut 11b is placed on the washer 11c. An engagement portion 12 (hook 12a) is joined to the side surface of the holding jig 11 (insertion metal fitting 11a).

[0039] When using auxiliary lifting means 14, the lower end of connecting member 15 (rod-shaped member 15a) constituting auxiliary lifting means 14 is connected to the upper part of the divided member constituting closure frame 8 by connecting portion 18. Connecting jig 16 (insertion metal fitting 16a, nut 16b, and washer 16c) constituting auxiliary lifting means 14 is kept separate from connecting member 15. An engaging portion 17 is joined to the side of connecting jig 16 (insertion metal fitting 16a).

[0040] 3, the lifting position changing means 9 are arranged at multiple locations so as to surround the outside of the insertion hole of the closure frame body 8 in a plan view, and the connection members 15 and linking parts 18 that constitute the lifting auxiliary means 14 are arranged at multiple locations on the outside of the lifting position changing means 9. The work of arranging the lifting position changing means 9 and the connection members 15 and linking parts 18 that constitute the lifting auxiliary means 14 on the closure frame body 8 (divided member) may be carried out in advance on land or on a ship before heading to the construction waters, or may be carried out on a work boat in the construction waters.

[0041] As illustrated in Figures 2 and 3, during construction work in the construction area where the superstructure 1 is to be constructed, the closure frame 8 is fitted onto the support 50 in a manner that allows it to move up and down. The lower ends of the multiple suspension position change devices 9 are connected to the upper part of the closure frame 8, and the engagement parts 12 of each suspension position change device 9 are engaged with the upper part of the support 50. The multiple suspension position change devices 9 then temporarily position the closure frame 8 at a predetermined height L1 above the support 50. In other words, the multiple suspension position change devices 9 suspend the closure frame 8 above the support 50. The predetermined height L1 (the height position of the upper surface of the closure frame 8) at which the closure frame 8 is temporarily positioned is set lower than the planned height L2 at which the bottom of the precast block 2 (block body 4) will be later installed above the support 50. The distance H between the predetermined height L1 and the planned height L2 is preferably set to, for example, 50 mm or more and 200 mm or less. In FIG. 2, the predetermined height L1 is indicated by a broken line, and the planned height L2 is indicated by a chain line.

[0042] More specifically, in this embodiment, when the closure frame 8 is temporarily positioned at a predetermined height L1, the engaging portions 12 of the multiple hanging position changing means 9 disposed on each of the divided members constituting the closure frame 8 are engaged with the upper portion of the support body 50. Then, each divided member constituting the closure frame 8 is suspended at the predetermined height L1 by the holding jig 11 fixed to the upper portion of the support body 50 via the engaging portions 12 and the hanging member 10 supported by the holding jig 11.

[0043] In this embodiment, hook 12a constituting engagement portion 12 is hooked onto the upper edge of support body 50, thereby enabling hook 12a and insert fitting 11a to be fixed to support body 50. Nut 11b, which is threaded into the thread groove of rod-shaped member 10a, is placed on insert fitting 11a via washer 11c, so that the load of closure frame 8 (divided member) is supported by insert fitting 11a and hook 12a, which are fixed to support body 50, via connecting portion 13, rod-shaped member 10a, and nut 11b.

[0044] The length of the suspension member 10 extending between the holding jig 11 (insertion metal fitting 11a) and the connecting portion 13 is adjusted so that the closure frame 8 is positioned at a predetermined height L1 with the engagement portion 12 engaged with the support body 50. In this embodiment, when the nut 11b is rotated in one direction on the insertion metal fitting 11a and washer 11c, the rod-shaped member 10a moves upward relative to the nut 11b, and when the nut 11b is rotated in the opposite direction on the insertion metal fitting 11a and washer 11c, the rod-shaped member 10a moves downward relative to the nut 11b. Therefore, by rotating the nut 11b to adjust the length of the rod-shaped member 10a extending between the holding jig 11 and the connecting portion 13, it is possible to adjust the height position of the closure frame 8.

[0045] The inner surface of each divided member constituting the closure frame 8 (the inner surface of the intervening member 8a) is in contact with the outer peripheral surface of the support body 50. The divided members are arranged so that no gaps are formed between adjacent divided members. In this embodiment, the protrusions 8b on the underside of each divided member are arranged below the underside of the adjacent divided member, so that the divided members support each other's load via the protrusions 8b.

[0046] When the closure frame 8 is configured from a single annular plate-like member in a plan view, the closure frame 8 with the multiple hanging position change means 9 arranged thereon is moved downward from above the support body 50 to fit over it, and the engaging portions 12 provided on each of the hanging position change means 9 are engaged with the upper part of the support body 50. Then, the hanging position change means 9 adjusts the height position of the closure frame 8 to a predetermined height L1.

[0047] 2 and 3, before the precast block 2 is installed on the support body 50, the upper ends of the connecting members 15 that make up the lifting auxiliary means 14 are free. If the connecting members 15 are tilted outward, this may hinder the subsequent installation of the precast block 2 on the support body 50. Therefore, it is advisable to bundle the upper parts of multiple connecting members 15 with a band 20 so that the connecting members 15 are tilted inward toward the support body 50. The band 20 may be made of, for example, a ring-shaped rubber member or a string-like member.

[0048] Furthermore, when working in the construction water area, a partition plate 40 is provided at a position a predetermined depth from the upper end of the support body 50 to separate the interior of the support body 50 into upper and lower parts. The outer dimensions of the partition plate 40 are set to be approximately the same as the inner dimensions of the support body 50. There are no particular limitations on the method for installing the partition plate 40 inside the support body 50, but for example, the partition plate 40 is fixed inside the support body 50 by supporting the partition plate 40 with a hanging material such as a wire suspended from the upper end of the support body 50.

[0049] The closure frame body 8 provided with multiple suspension position change means 9 is relatively lightweight, so it can be lifted by one or several workers. Therefore, the closure frame body 8 provided with multiple suspension position change means 9 can be moved to the vicinity of the support body 50 using a small boat (a raft is also acceptable) floating on the water, and a worker on the boat can manually temporarily position the closure frame body 8 at a predetermined height L1 of the support body 50. The installation work of the closure frame body 8 and suspension position change means 9 on the support body 50 can also be performed using a crane on a work boat, for example.

[0050] After the closure frame 8 is temporarily positioned on the support body 50, the precast block 2 is installed on the support body 50 and temporarily fixed thereto. Specifically, wire ropes suspended from a crane on a work vessel are connected to each of the lifting fittings 7 on the precast block 2, and the precast block 2 is lifted above the support body 50 by the crane. Next, with the through holes 3 in the precast block 2 aligned with the support body 50, the precast block 2 is moved downward from above the support body 50. Then, as illustrated in Figures 6 and 7, with the support body 50 loosely inserted into the through holes 3 of the precast block 2, the precast block 2 is temporarily fixed to the support body 50.

[0051] In this embodiment, by placing the beam member 6 that protrudes inside the through hole 3 on the upper end of the support body 50, the bottom surface of the precast block 2 is positioned at the planned height L2, and the precast block 2 is temporarily fixed to the top of the support body 50. Once the precast block 2 is temporarily fixed to the top of the support body 50, workers can stand on the precast block 2 to perform work. In this state, the temporarily positioned closure frame body 8 is positioned at a predetermined height L1 that is lower than the planned height L2 at which the bottom surface of the precast block 2 (block body 4) is positioned, and the top surface of the closure frame body 8 and the bottom surface of the precast block 2 are spaced apart.

[0052] When using the auxiliary lifting means 14, the bands 20 bundling the connecting members 15 constituting each auxiliary lifting means 14 are removed. Next, a connecting jig 16 is attached to the top of each connecting member 15, and the connecting jig 16 is engaged with the engaged portion 3b (the upper end of the sheath tube 5) provided on the inner periphery 3a of the through hole 3 of the precast block 2 by the engaging portion 17. The closure frame body 8 and the engaged portion 3b are then connected by the connecting jig 16 fixed to the engaged portion 3b via the engaging portion 17 and the connecting member 15 supported by the connecting jig 16. As a result, the closure frame body 8 is suspended from the precast block 2 (block body 4) by the connecting jig 16 (insertion metal fitting 16a) fixed to the engaged portion 3b via the engaging portion 17 and the connecting member 15 supported by the connecting jig 16 (insertion metal fitting 16a, nut 16b).

[0053] More specifically, in this embodiment, the insert fitting 16a and washer 16c are inserted into the upper part of the rod-shaped member 15a, which is the connecting member 15, and the hook 17a attached to the insert fitting 16a is hooked onto the edge of the upper end of the sleeve tube 5. Next, the nut 16b is screwed onto the upper end of the rod-shaped member 15a, and the nut 16b is rotated relative to the rod-shaped member 15a until the nut 16b is placed on the washer 16c.

[0054] In this embodiment, the hook 17a is hooked onto the edge of the upper end of the sheath pipe 5, thereby fixing the hook 17a and the insert fitting 16a to the precast block 2 (sheath pipe 5). The nut 16b, which is threaded into the thread groove of the rod-shaped member 15a, is placed on the insert fitting 16a via the washer 16c, so that the load of the closure frame 8 is also supported by the insert fitting 16a and hook 17a, which are fixed to the precast block 2 (sheath pipe 5), via the connecting portion 18, the rod-shaped member 15a, and the nut 16b.

[0055] As illustrated in FIG. 7 , each of the suspension position change means 9 and the suspension auxiliary means 14 is positioned to avoid the beam member 6 in plan view. When the precast block 2 is temporarily fixed to the support 50, the center of the support 50 may be misaligned with the center of the through hole 3 in the precast block 2 in plan view. Even in this case, the connecting members 15 (rod-shaped members 15a) constituting each of the suspension auxiliary means 14 can absorb the misalignment by tilting or warping in accordance with the misalignment between the support 50 and the precast block 2. As in this embodiment, when the lower end of the connecting member 15 is connected to the upper part of the closure frame 8 via a connecting portion 18 that can change the angle (direction) of the connecting member 15, the connecting member 15 tilts in accordance with the misalignment between the support 50 and the precast block 2, which is advantageous for reducing the load on the connecting member 15.

[0056] Next, as shown in Figure 8, the engaging portion 12 provided on each hanging position changing means 9 is engaged with either the upper portion of the support body 50 or the engaged portion 3b provided on the inner peripheral portion 3a of the through hole 3 of the precast block 2, and by operating each hanging position changing means 9 from above the precast block 2, the blocking frame body 8 is raised from a predetermined height L1 relative to the support body 50. Then, the upper surface of the blocking frame body 8 is brought into contact with the bottom surface of the precast block 2 (block body 4), and the blocking frame body 8 closes the gap between the outer peripheral surface of the support body 50 and the lower end of the through hole 3 of the precast block 2.

[0057] This embodiment illustrates a case where each of the hanging position changing means 9 is operated from above the precast block 2 with the engaging portions 12 provided on each of the hanging position changing means 9 engaged with the upper portion of the support body 50. In this case, the closing frame body 8 is used to close the gap between the outer peripheral surface of the support body 50 and the lower end of the through hole 3 of the precast block 2, and the closing frame body 8 is fixed to the support body 50 by the multiple hanging position changing means 9. A case where the engaging portions 12 provided on each of the hanging position changing means 9 are engaged with the engaged portions 3b provided on the inner peripheral portion 3a of the through hole 3 of the precast block 2 before operating the hanging position changing means 9 will be described in another embodiment illustrated later.

[0058] In this embodiment, the closure frame 8 is raised from a predetermined height L1 by operating each holding jig 11 from above the precast block 2 and moving the suspending member 10 upward relative to the holding jig 11. Then, the suspending member 10 is fixed to the holding jig 11 at a position where the upper surface of the closure frame 8 abuts against the bottom surface of the precast block 2.

[0059] When using the auxiliary lifting means 14, the connecting jigs 16 are operated from above the precast block 2 to move the connecting members 15 upward relative to the connecting jigs 16, thereby raising the closure frame 8 from the predetermined height L1. Then, the connecting members 15 are fixed to the connecting jigs 16 at a position where the upper surface of the closure frame 8 abuts against the bottom surface of the precast block 2.

[0060] More specifically, by rotating nuts 11b constituting each holding jig 11 on insert fittings 11a and washers 11c from above precast block 2, rod-shaped member 10a is moved upward relative to insert fittings 11a, washers 11c, and nuts 11b. Furthermore, by rotating nuts 16b constituting each connecting jig 16 on insert fittings 16a and washers 16c from above precast block 2, rod-shaped member 15a is moved upward relative to insert fittings 16a, washers 16c, and nuts 16b. Then, when the top surface of closure frame 8 abuts against the bottom surface of precast block 2, the rotation of nuts 11b and 16b is stopped.

[0061] If there is a large variation in the amount of lift of each of the suspending members 10 and connecting members 15 during the process of lifting the closure frame 8, the load and strain on the suspension position changing means 9, the auxiliary suspension means 14, and the closure frame 8 will increase. For this reason, it is preferable to gradually lift each of the suspending members 10 and connecting members 15 in a balanced manner by sequentially changing the suspending members 10 and connecting members 15 to be lifted so that the amount of lift of each of the suspending members 10 and connecting members 15 is roughly equal. In this embodiment, the amount of lift of each of the suspending members 10 and connecting members 15 can be finely adjusted by adjusting the amount of rotation of each of the nuts 11b and 16b.

[0062] The nut 11b that constitutes the holding jig 11 can be rotated by hand by an operator, but as shown in Figure 9, the nut 11b can be rotated more efficiently by using an impact driver 60 and fitting tool 61. A well-known impact driver 60 used for fastening screws and bolts can be used. A fitting tool 61 made to fit the shape of the nut 11b is attached to the rotation shaft of the impact driver 60, to which a bit is usually attached. The fitting tool 61 is composed of a tubular member that extends vertically, and is designed so that the nut 11b can be fitted into the lower end of the fitting tool 61.

[0063] As shown in FIG. 9, the nut 11b is fitted into the lower end of the fitting 61, and the upper portion of the rod-shaped member 15a extending above the nut 11b is inserted into the hollow portion of the fitting 61. The fitting 61 is then rotated together with the rotation shaft of the impact driver 60 to rotate the nut 11b. A drill driver may be used instead of the impact driver 60. When the nut 11b is rotated to move the rod-shaped member 15a upward relative to the connecting jig 16, the length of the portion of the rod-shaped member 15a extending above the nut 11b increases. Therefore, it is preferable to set the longitudinal dimension (vertical direction) of the fitting 61 to be longer than the distance H between the predetermined height L1 and the planned height L2. When the longitudinal dimension (vertical direction) of the fitting 61 is made shorter than the separation distance H, the work of lifting the rod-shaped member 15a can be temporarily stopped and the upper part of the rod-shaped member 15a extending above the nut 11b can be cut off. Similarly, the nut 16b constituting the connecting jig 16 can also be rotated efficiently by using the impact driver 60 and the fitting 61.

[0064] After the blocking frame 8 is fixed to the support 50, as illustrated in FIGS. 10 and 11 , the gap between the outer surface of the support 50 and the lower end of the through-hole 3 in the precast block 2 is blocked by the blocking frame 8. Then, from above the precast block 2, filler material 30 is filled between the outer surface of the support 50 and the inner surface of the through-hole 3. More specifically, filler material 30 is filled into the inside of the support 50 above the partition plate 40, the gap between the outer surface of the support 50 above the blocking frame 8 and the inner surface of the through-hole 3, and the upper part of the through-hole 3 above the support 50. Examples of filler material 30 include ready-mixed concrete and liquid resin that hardens after curing. In FIGS. 10 and 11 , the area filled with filler material 30 is indicated by diagonal lines.

[0065] During the process of filling the filler material 30, the weight of the filler material 30 is applied to the closing frame 8, but this load is supported by the multiple hanging position changing means 9. If auxiliary hanging means 14 are provided, the load of the filler material 30 is also supported by the multiple auxiliary hanging means 14. This allows the closing frame 8 to maintain a state in which the gap between the outer peripheral surface of the support body 50 and the lower end of the through hole 3 in the precast block 2 is closed.

[0066] After that, the fill material 30 is cured for a predetermined period of time to harden, and the superstructure 1, which is an integrated unit of the precast blocks 2 and the hardened fill material 30, is fixed to the top of the support 50. This completes the construction work of the superstructure 1. The respective suspension position change means 9 and suspension auxiliary means 14 are embedded in the fill material 30. The blocking frame 8 becomes part of the superstructure 1. The suspension fittings 7 may be removed from the superstructure 1, or may be left as they are.

[0067] As described above, in the method for constructing the superstructure 1, the blocking frame body 8 is fitted onto the support body 50 in a state in which it can be moved up and down, the lower ends of the multiple hanging position change means 9 are each connected to the upper part of the blocking frame body 8, and the engagement parts 12 provided on each hanging position change means 9 are engaged with the upper part of the support body 50, and the multiple hanging position change means 9 temporarily position the blocking frame body 8 at a predetermined height L1 of the support body 50. Then, the precast block 2 having the through hole 3 is moved downward from above the support body 50, and the precast block 2 is temporarily fixed to the support body 50 with the support body 50 loosely inserted into the through hole 3, thereby completing the installation of the precast block 2 on the support body 50.

[0068] Thereafter, with the engaging portion 12 provided on each of the suspension position changing means 9 engaged with either the upper portion of the support body 50 or the engaged portion 3b provided on the inner peripheral portion 3a of the through hole 3 of the precast block 2, each of the suspension position changing means 9 is operated from above the precast block 2 to raise the closure frame body 8 from the predetermined height L1 relative to the support body 50. Then, the upper surface of the closure frame body 8 is abutted against the bottom surface of the precast block 2, and the closure frame body 8 closes the gap between the outer peripheral surface of the support body 50 and the lower end of the through hole 3 of the precast block 2. This allows the closure frame body 8 to close the gap between the outer peripheral surface of the support body 50 and the lower end of the through hole 3 of the precast block 2 without requiring complicated work below the precast block 2 installed on the support body 50. By using multiple hanging position change means 9, the upper surface of the blocking frame body 8 is pressed against the bottom surface of the precast block 2, effectively preventing distortion or tilting of the blocking frame body 8 and the creation of a gap between the bottom surface of the precast block 2 and the upper surface of the blocking frame body 8.

[0069] Thereafter, by filling and solidifying the filler material 30 between the outer peripheral surface of the support 50 and the inner peripheral surface of the through-hole 3 of the precast block 2, the superstructure 1 above water can be efficiently constructed without performing complicated work below the precast blocks 2 installed on the support 50. With this construction method, it is not necessary to perform diving work or work above water under the precast blocks 2 installed on the support 50, and therefore the construction efficiency of constructing the superstructure 1 above water and the safety of workers can be improved.

[0070] For example, if the suspension position change means 9 is welded or adhesively joined to the top of the support 50 without providing the engagement portion 12 to the suspension position change means 9, the work of fixing the suspension position change means 9 to the top of the support 50 takes a lot of time and requires tedious work to be performed on the precast block 2. If welding is performed, there is a risk that molten metal will fall onto the closure frame 8 and damage the closure frame 8. In contrast, if the suspension position change means 9 is provided with the engagement portion 12, tedious work on the precast block 2 is not required and the suspension position change means 9 can be easily fixed to the top of the support 50 with fewer work steps. Therefore, providing the engagement portion 12 to the suspension position change means 9 can improve the work efficiency of constructing the superstructure 1.

[0071] In this embodiment, the suspension position change means 9 is configured with a suspending member 10 whose lower end is connected to the upper part of the closure frame 8 and a holding jig 11 that holds the suspending member 10 in a state where it can be moved vertically relative to the closure frame 8. The holding jig 11 is provided with an engaging portion 12, which allows the suspending position change means 9 to be simply configured. To temporarily position the closure frame 8 at a predetermined height L1, simply engage and fix the engaging portion 12 with the upper part of the support 50, and the closure frame 8 can be suspended at the predetermined height L1 by the engaging portion 12, the holding jig 11, and the suspending member 10. Therefore, the temporary positioning of the closure frame 8 at the predetermined height L1 can be easily and efficiently performed. Furthermore, the closure frame 8 can be raised relative to the support 50 simply by operating the holding jig 11 from above the precast block 2 and moving the suspending member 10 upward relative to the holding jig 11. Therefore, the operation of placing the upper surface of the closure frame 8 in abutment with the bottom surface of the precast block 2 can also be easily and efficiently performed.

[0072] As in this embodiment, by using a rod-shaped member 10a with a threaded groove as the hanging member 10, and using an insert metal fitting 11a with an engaging portion 12 and a nut 11b that screws into the threaded groove of the rod-shaped member 10a as the holding jig 11, the hanging position changing means 9 can be configured very simply. When raising the closure frame 8 from the predetermined height L1, the worker does not need to lift the rod-shaped member 10a by hand, and can raise the rod-shaped member 10a simply by turning the nut 11b, so the closure frame 8 can be raised easily with a small number of workers.

[0073] Furthermore, by adjusting the amount of rotation (number of rotations) of the nut 11b, the amount of lift of the rod-shaped member 10a can be finely adjusted, allowing the lift of each of the multiple rod-shaped members 10a provided in the closure frame 8 in a balanced manner. When the closure frame 8 abuts against the bottom surface of the precast block 2, the nut 11b becomes difficult to rotate, making it easy to determine from above the precast block 2 whether the closure frame 8 abuts against the bottom surface of the precast block 2, and allowing the closure frame 8 to be pressed against the bottom surface of the precast block 2 with an appropriate amount of force. This is therefore advantageous for reducing the risk of excessive load or distortion on the suspension position change means 9 and the closure frame 8, and for the closure frame 8 to stably close the gap between the outer peripheral surface of the support 50 and the lower end of the through hole 3 in the precast block 2.

[0074] In this embodiment, the engagement portions 12 of each of the suspension position change means 9 are engaged with the upper portion of the support 50, and the closure frame 8 closes the gap between the bottom surface of the precast block 2 and the upper surface of the closure frame 8. In this case, if the engagement portion 3b provided on the inner periphery 3a of the through hole 3 of the precast block 2 is connected to the upper portion of the closure frame 8 by multiple suspension auxiliary means 14, the weight of the closure frame 8 and the fill material 30 can be supported not only by the multiple suspension position change means 9 but also by the multiple suspension auxiliary means 14. In addition, the weight of the closure frame 8 and the fill material 30 can be distributed not only to the support 50 but also to the precast block 2. Furthermore, since the closure frame 8 can be suspended at a position close to the area where it abuts against the bottom surface of the precast block 2 by the multiple suspension auxiliary means 14, the separation between the upper surface of the closure frame 8 and the bottom surface of the precast block 2 can be effectively prevented. Therefore, it is more advantageous for the closing frame 8 to stably close the gap between the outer peripheral surface of the support 50 and the lower end of the through hole 3 in the precast block 2.

[0075] Furthermore, as in this embodiment, by using a precast block 2 into which a sheath pipe 5 that forms a through hole 3 is fitted, and configuring the engaged portion 3b as the upper end of the sheath pipe 5 so that the engaging portion 17 provided on the lifting auxiliary means 14 engages with the upper end of the sheath pipe 5, the lifting auxiliary means 14 can be connected to the precast block 2 very easily.

[0076] The auxiliary lifting means 14 can be configured simply by configuring the connecting member 15, the lower end of which is connected to the upper part of the closure frame 8, and the connecting jig 16, which holds the connecting member 15 in a state where it can move relatively in the vertical direction, and by providing the connecting jig 16 with an engaging portion 17. As in this embodiment, when the closure frame 8 is temporarily positioned at a predetermined height L1, the engaging portion 17 is engaged with and fixed to the upper part of the sleeve tube 5, and the closure frame 8 is suspended at the predetermined height L1 by the engaging portion 17, the connecting jig 16, and the connecting member 15. This allows the load of the closure frame 8 to be supported not only by the multiple hanging position changing means 9, but also by the multiple auxiliary lifting means 14. When raising the blocking frame body 8 from a predetermined height L1, the hanging position change means 9 is operated together with the connecting jig 16 of the hanging auxiliary means 14, and the connecting member 15 is moved upward relative to the connecting jig 16, thereby effectively preventing the blocking frame body 8 from tilting or distorting during the process of raising the blocking frame body 8.

[0077] For example, if the connecting jig 16 is joined to the sheath pipe 5 by welding or adhesive without providing the engaging portion 17 on the connecting jig 16, the task of fixing the connecting jig 16 to the sheath pipe 5 takes a lot of time and requires complicated work to be done on the precast block 2. If welding is performed, there is a risk that molten metal will fall onto the closure frame 8 and damage the closure frame 8. In contrast, if the connecting jig 16 is provided with the engaging portion 17, it is not necessary to perform complicated work on the precast block 2, and the connecting jig 16 can be easily fixed to the sheath pipe 5 with few work steps.

[0078] Furthermore, as in this embodiment, by using rod-shaped member 15a with a thread as connecting member 15, and using insert fitting 16a with engaging portion 17 as connecting jig 16 and nut 16b that screws into the thread of connecting member 15, it is possible to configure auxiliary lifting means 14 very simply. When raising closure frame body 8 from predetermined height L1 relative to support body 50, the worker does not need to manually lift rod-shaped member 15a, and can raise rod-shaped member 15a simply by rotating nut 16b, so that closure frame body 8 can be easily raised with a small number of workers.

[0079] Furthermore, by adjusting the amount of rotation (number of rotations) of nut 16b, the amount of lift of rod-shaped member 15a can be finely adjusted, allowing for balanced lifting of each of the multiple rod-shaped members 15a provided on closure frame 8. When closure frame 8 abuts against the bottom surface of precast block 2, nut 16b becomes difficult to rotate. This makes it easy to determine from above precast block 2 whether closure frame 8 abuts against the bottom surface of precast block 2, allowing closure frame 8 to be pressed against the bottom surface of precast block 2 with an appropriate amount of force. This is therefore advantageous for reducing the risk of excessive load or distortion on suspension auxiliary means 14, suspension position change means 9, and closure frame 8, and is more advantageous for stably sealing the gap between the outer peripheral surface of support 50 and the lower end of through-hole 3 in precast block 2 with closure frame 8.

[0080] In this embodiment, the hoisting position changing means 9 and the auxiliary hoisting means 14 are provided at 12 locations on the closure frame 8, but the number and arrangement of the hoisting position changing means 9 and the auxiliary hoisting means 14 provided on the closure frame 8 can be determined appropriately depending on the size and weight of the closure frame 8. It is preferable that the hoisting position changing means 9 and the auxiliary hoisting means 14 be provided at 8 to 16 locations, for example. Providing the hoisting position changing means 9 and the auxiliary hoisting means 14 at 8 to 16 locations on the closure frame 8 is advantageous for stably sealing the gap between the outer peripheral surface of the support body 50 and the lower end of the through hole 3 in the precast block 2 using the closure frame 8 while relatively reducing the amount of work required to operate the hoisting position changing means 9 and the auxiliary hoisting means 14.

[0081] In this embodiment, an example is given of the case where the upper end of the sheath pipe 5 provided on the precast block 2 is used as the engaged part 3b, but for example, instead of providing a sheath pipe 5 on the precast block 2, it is also possible to provide a groove or metal fitting on the concrete surface of the inner periphery 3a of the through hole 3 of the precast block 2 as the engaged part 3b, with which the engaging part 17 provided on the lifting auxiliary means 14 can engage.

[0082] As in this embodiment, when fabricating the precast block 2, if a beam member 6 is provided that protrudes inside the through hole 3 of the precast block 2, then by placing the beam member 6 on the upper end of the support body 50, the precast block 2 can be easily and stably temporarily fixed to the top of the support body 50. After the precast block 2 is temporarily fixed to the top of the support body 50, workers can stand on the precast block 2 to perform work, which is advantageous for improving construction efficiency.

[0083] The number and arrangement of the beam members 6 constituting the precast block 2 are not limited to the embodiment exemplified above, and for example, there can be one or three or more beam members 6 protruding inside the through hole 3. Also, for example, a configuration can be adopted in which the end of the beam member 6 is arranged inside the through hole 3 in a plan view, and the beam member 6 does not cross the through hole 3. Also, for example, a configuration can be adopted in which two beam members 6 are arranged side by side inside the through hole 3 in a plan view.

[0084] In this construction method, the hanging members 10 and holding jigs 11 that make up the hanging position change means 9, the engagement parts 12 provided on the hanging position change means 9, the connection members 15 and connecting jigs 16 that make up the hanging auxiliary means 14, and the engagement parts 17 provided on the hanging auxiliary means 14 can also be configured as shown, for example, in Figures 12 to 15. The functions of the hanging position change means 9, engagement parts 12, hanging auxiliary means 14, and engagement parts 17 are the same as those of the embodiment illustrated in Figures 1 to 11. The other components used in constructing the superstructure 1 are the same as those of the embodiment illustrated in Figures 1 to 11.

[0085] As shown in Figure 12, in this embodiment, string-like members 10b are used as the hanging members 10 constituting the hanging position changing means 9, and a restraining jig 11d is used as the holding jig 11, which is capable of switching between a restrained state and an unrestrained state for the string-like members 10b. The holding jig 11 (restraining jig 11d) is provided with an inserting tool 12b as the engaging part 12. Furthermore, similar to the hanging position changing means 9, string-like members 15b are used as the connecting members 15 constituting the hanging auxiliary means 14, and a restraining jig 16d is used as the connecting jig 16, which is capable of switching between a restrained state and an unrestrained state for the string-like members 15b. The connecting jig 16 (restraining jig 16d) is provided with an inserting tool 17b as the engaging part 17.

[0086] The string-like members 10b, 15b can be formed, for example, from wire, wire rope, resin rope, string, belt, etc. The restraining jigs 11d, 16d can be formed, for example, from a known ratchet used for fall prevention in mountain climbing, etc. The restraining jig 11d (16d) of this embodiment has a self-locking function (automatic tightening function) in which the string-like member 10b (15b) inserted into the restraining jig 11d (16d) can move only to one side of the restraining jig 11d (16d) and cannot move to the other side.

[0087] As illustrated in FIGS. 12 and 13 , when the closure frame 8 is temporarily positioned at a predetermined height L1, the closure frame 8 is suspended at the predetermined height L1 by a restraining jig 11d fixed to the upper part of the support body 50 via the engaging portion 12 and a string-like member 10b restrained by the restraining jig 11d. More specifically, in this embodiment, the lower ends of the string-like members 10b are connected to ring-shaped connecting portions 13 provided at multiple locations on the upper part of the closure frame 8, respectively, and the lower ends of the string-like members 15b are connected to ring-shaped connecting portions 18 provided at multiple locations on the upper part of the closure frame 8, respectively. In this embodiment, engaging members 50a are disposed at multiple locations on the outer peripheral surface of the upper part of the support body 50. The restraining jig 11d is fixed to the upper part of the support body 50 by engaging (inserting) the inserting members 12b provided on the restraining jig 11d with the engaging members 50a.

[0088] The middle portion of string-like member 10b is inserted into restraining jig 11d, and string-like member 10b extending between restraining jig 11d and connecting portion 13 is put into a taut state (stretched state), so that the middle portion of string-like member 10b is restrained by restraining jig 11d. That is, closure frame 8 is suspended relative to support body 50 by restraining jig 11d fixed to the upper part of support body 50 via insertion tool 12b and string-like member 10b supported by restraining jig 11d. The upper part of string-like member 10b protruding from the upper part of restraining jig 11d is hung down inside support body 50.

[0089] With the closure frame 8 temporarily positioned at a predetermined height L1, it is advisable to use adhesive tape 21 to attach the middle of the string-like member 15b, which is the connecting member 15, to the outer surface of the restraining jig 11d, which is the holding jig 11. In this embodiment, no groove 4a is provided in the precast block 2, and instead, engaged parts 5a are arranged as engaged parts 3b at multiple locations on the inner surface of the upper part of the sheath tube 5, which can engage with engaging parts 17 (insertion parts 17b) provided on the suspension auxiliary means 14.

[0090] 14, after the precast block 2 is placed on the support body 50 and temporarily fixed, the adhesive tape 21 that has been bonding the restraining jig 11d and the string-like members 15b together is removed. Next, the middle of each string-like member 15b is inserted into the restraining jig 16d that constitutes the connecting jig 16. Then, the inserting member 17b provided on the restraining jig 16d is engaged with (inserted into) the engaged member 5a provided on the inner surface of the upper part of the sleeve pipe 5, thereby fixing the restraining jig 16d to the upper part of the sleeve pipe 5.

[0091] Through the above-described work, the closure frame 8 and the sheath pipe 5 are connected by the restraining jig 16d fixed to the upper part of the sheath pipe 5 via the inserting tool 17b and the string-like member 15b supported by the restraining tool 16d. Next, the string-like member 15b is pulled upward from above the precast block 2, bringing the string-like member 15b extending between the restraining jig 16d and the connecting portion 18 into a taut state (stretched state), and the middle portion of the string-like member 15b is restrained by the restraining jig 16d. In other words, the closure frame 8 is suspended relative to the sheath pipe 5 by the restraining jig 16d fixed to the upper part of the sheath pipe 5 via the inserting tool 17b and the engaged tool 5a, and the string-like member 15b supported by the restraining tool 16d.

[0092] 14 and 15, when the closure frame 8 is raised from the predetermined height L1 relative to the support 50, the string-shaped member 10b is released from the restraining state of the restraining jig 11d, which is the holding jig 11, by lifting the upper part of the string-shaped member 10b upward, thereby moving the string-shaped member 10b upward relative to the restraining jig 11d. Furthermore, the string-shaped member 15b is released from the restraining state of the restraining jig 16d, which is the connecting jig 16, by lifting the upper part of the string-shaped member 15b upward, thereby moving the string-shaped member 15b upward relative to the restraining jig 16d. Then, as shown in FIG. 15, when the top surface of the closure frame 8 abuts against the bottom surface of the precast block 2, the string-shaped member 10b is restrained by the restraining jig 11d, which is the holding jig 11, and the string-shaped member 15b is restrained by the restraining jig 16d, which is the connecting jig 16. By performing the above operations, the closure frame 8 closes the gap between the outer peripheral surface of the support 50 and the lower end of the through hole 3 in the precast block 2.

[0093] If the variation in the length to which each string-like member 10b, 15b is lifted increases during the process of lifting the closure frame 8, the load and strain on the hanging position changing means 9, the lifting auxiliary means 14, and the closure frame 8 will increase. Therefore, it is preferable to lift each string-like member 10b, 15b in a balanced manner by sequentially changing the string-like members 10b, 15b being lifted so that the lengths to which each string-like member 10b, 15b is lifted are approximately equal. When the closure frame 8 abuts against the bottom surface of the precast block 2, the string-like members 10b, 15b cannot be lifted. Therefore, it is easy to determine from above the precast block 2 whether the closure frame 8 abuts against the bottom surface of the precast block 2, and the closure frame 8 can be pressed against the bottom surface of the precast block 2 with an appropriate force.

[0094] After the gap between the outer peripheral surface of the support 50 and the lower end of the through-hole 3 in the precast block 2 is sealed with the closure frame 8, the filler material 30 is filled between the outer peripheral surface of the support 50 and the inner peripheral surface of the through-hole 3 from above the precast block 2, as in the embodiment illustrated in Figures 10 and 11. The filler material 30 is then cured for a predetermined period of time to harden, thereby fixing the superstructure 1, which integrates the precast block 2 and the hardened filler material 30, to the top of the support 50. This completes the construction of the superstructure 1. The lifting position change means 9 and lifting auxiliary means 14 are each embedded in the filler material 30.

[0095] As in this embodiment, by using string-like members 10b as the hanging members 10 constituting the hanging position changing means 9 and by using restraining jig 11d having engaging portions 12 as the holding jig 11, the hanging position changing means 9 can be configured simply. In addition, by using string-like members 15b as the connecting members 15 constituting the hanging auxiliary means 14 and by using restraining jig 16d having engaging portions 17 as the connecting jig 16, the hanging auxiliary means 14 can be configured simply.

[0096] To temporarily position the closure frame 8 at the predetermined height L1, the engagement portion 12 provided on the suspension position changing means 9 is simply engaged with and fixed to the upper portion of the support 50, allowing the closure frame 8 to be suspended at the predetermined height L1 by the engagement portion 12, the restraining jig 11d, and the string-like member 10b. Therefore, the temporary positioning of the closure frame 8 at the predetermined height L1 can be easily and efficiently performed. Furthermore, the closure frame 8 can be raised relative to the support 50 simply by pulling the string-like member 10b (15b) upward from above the precast block 2 and moving the string-like member 10b (15b) upward relative to the restraining jig 11d (16d). Therefore, the operation of bringing the upper surface of the closure frame 8 into contact with the bottom surface of the precast block 2 can also be easily and efficiently performed.

[0097] When the restraining jig 11d (16d) having a self-locking function (automatic tightening function) is used as in this embodiment, even if the worker releases the string-like member 10b (15b) when raising the closure frame 8 from the predetermined height L1, the string-like member 10b (15b) is automatically restrained by the restraining jig 11d (16d). This reduces the risk of the closure frame 8 unintentionally falling, which is advantageous for performing the work of raising the closure frame 8 more safely.

[0098] The method for constructing an above-water superstructure 1 of the present invention can also be configured as shown in Figures 16 to 19. As shown in Figure 16, the configurations of the precast blocks 2, closure frame 8, lifting position change means 9, and engagement portion 12 used in this embodiment are the same as those of the previous embodiment shown in Figures 1 to 11. This embodiment differs from the previous embodiment shown in Figures 1 to 11 in that it does not use the lifting auxiliary means 14. Other differences are explained below.

[0099] 16, in this embodiment, the suspension position changing means 9 are arranged at multiple locations so as to surround the outside of the insertion hole of the blocking frame body 8 in a plan view. Then, during work in the construction water area where the superstructure 1 is to be constructed, the blocking frame body 8 is fitted onto the support body 50 in a state where it can be moved up and down, the lower ends of the multiple suspension position changing means 9 are each connected to the upper part of the blocking frame body 8, and the engagement parts 12 provided on each suspension position changing means 9 are engaged with the upper part of the support body 50, so that the multiple suspension position changing means 9 temporarily position the blocking frame body 8 at a predetermined height L1 above the support body 50.

[0100] More specifically, in this embodiment, when the closure frame body 8 is temporarily placed at a predetermined height L1, the engagement portions 12 (hooks 12a) provided on the plurality of hanging position changing means 9 are each brought into a state of being engaged with the upper part of the support body 50. Then, by means of the holding jig 11 (insertion fitting 11a, nut 11b, washer 11c) fixed to the upper part of the support body 50 via the engagement portions 12 and the hanging member 10 supported by the holding jig 11, each of the divided members constituting the closure frame body 8 is brought into a state of being suspended at the predetermined height L1.

[0101] 17, a precast block 2 having a through hole 3 that passes through vertically and into which the support 50 can be loosely inserted is moved downward from above the support 50, and the precast block 2 is temporarily fixed to the support 50 with the support 50 loosely inserted into the through hole 3. In this state, the closure frame 8 is suspended from the support 50 by a holding jig 11 (insertion metal fitting 11a) fixed to the top of the support 50 via an engagement portion 12, and a hanging member 10 supported by the holding jig 11 (insertion metal fitting 11a, nut 11b).

[0102] 18, in this embodiment, the engaging portions 12 provided on each of the suspension position changing means 9 are removed from the upper portion of the support body 50, and the engaging portions 12 provided on each of the suspension position changing means 9 are brought into engagement with the engaged portions 3b provided on the inner periphery 3a of the through hole 3 of the precast block 2. More specifically, in this embodiment, the engaging portions 12 (hooks 12a) provided on the holding jigs 11 arranged on the upper portion of each of the suspension members 10 (rod-shaped members 10a) are removed from the upper portion of the support body 50, and the removed engaging portions 12 are brought into engagement with the upper end of the sleeve tube 5, which is the engaged portion 3b. As a result, the closure frame 8 is suspended from the precast block 2 by the holding jigs 11 (insertion fittings 11a) fixed to the engaged portions 3b (upper portion of the sleeve tube 5) via the engaging portions 12, and the suspension members 10 supported by the holding jigs 11 (insertion fittings 11a, nuts 11b). The operation of removing the engaging portion 12 provided on the hanging position change means 9 from the top of the support body 50 and engaging it with the engaged portion 3b should not be performed simultaneously on multiple hanging position change means 9, but should be performed sequentially on each location.

[0103] In this embodiment, nut 11b is rotated relative to rod-shaped member 10a, moving nut 11b upward relative to rod-shaped member 10a and moving insert fitting 11a, washer 11c, and engaging portion 12 (hook 12a) upward, thereby removing engaging portion 12 and holding jig 11 from the top of support body 50. Next, by engaging the removed engaging portion 12 with the top of sleeve tube 5, insert fitting 11a and washer 11c are positioned near the top of sleeve tube 5 with rod-shaped member 10a inserted. Then, nut 11b is rotated relative to rod-shaped member 10a, moving nut 11b downward relative to rod-shaped member 10a, so that nut 11b is positioned on top of insert fitting 11a.

[0104] 19, by operating each of the hanging position changing means 9 from above the precast block 2, the blocking frame body 8 is raised from a predetermined height L1 relative to the support body 50, and the upper surface of the blocking frame body 8 is brought into contact with the bottom surface of the precast block 2 (block body 4), so that the blocking frame body 8 closes the gap between the outer peripheral surface of the support body 50 and the lower end of the through hole 3 of the precast block 2. That is, in this embodiment, the blocking frame body 8 is fixed to the precast block 2 by the multiple hanging position changing means 9.

[0105] Thereafter, as in the embodiment illustrated in Figure 10, fill material 30 is filled between the outer surface of the support 50 and the inner surface of the through hole 3 and allowed to solidify, thereby fixing the superstructure 1, which is an integral part of the precast block 2 and the solidified fill material 30, to the top of the support 50.

[0106] 1 to 11. In this embodiment, even when the engaging portions 12 provided on each of the suspension position change means 9 are engaged with the engaged portions 3b provided on the inner peripheral portion 3a of the through hole 3 of the precast block 2 after the precast block 2 is temporarily fixed to the support body 50, the same effects as those of the previous embodiment illustrated in Figures 1 to 11 can be achieved. With the configuration of this embodiment, the closure frame body 8 is fixed to the precast block 2 by the multiple suspension position change means 9 while the closure frame body 8 closes the gap between the outer peripheral surface of the support body 50 and the lower end of the through hole 3 of the precast block 2, which is more advantageous in preventing the upper surface of the closure frame body 8 and the bottom surface of the precast block 2 from separating.

[0107] On the other hand, as in the embodiment illustrated in Figures 1 to 11, if the precast block 2 is temporarily fixed to the support body 50 and then the engaging portion 12 provided on each hanging position change means 9 is left engaged with the upper part of the support body 50, there is no need to remove the engaging portion 12 from the upper part of the support body 50 and engage it with the engaged portion 3b, which is advantageous in reducing the amount of work required to construct the superstructure 1.

[0108] In this embodiment, the case where the upper end of the sheath pipe 5 provided on the precast block 2 is used as the engaged portion 3b has been exemplified, but for example, instead of providing the sheath pipe 5 on the precast block 2, a configuration is also possible in which a groove or metal fitting is provided on the concrete surface of the inner periphery 3a of the through hole 3 of the precast block 2 as the engaged portion 3b that can engage with the engaging portion 12 provided on the hanging position changing means 9. For example, a configuration is also possible in which the sheath pipe 5 is provided on the precast block 2, and a groove or metal fitting is provided on the inner surface of the sheath pipe 5 as the engaged portion 3b.

[0109] In the above-described embodiment, the support body 50 is placed at a position higher than the water surface level WL with the closure frame 8 temporarily placed at a predetermined height L1 of the support body 50, but for example, the predetermined height L1 can also be set to the water surface level WL. In that case, a buoyant body can be provided below the closure frame 8, and the closure frame 8 can be temporarily placed in a state where it floats on the water by the buoyant body. The buoyant body can be, for example, a hollow box, or a foam having many air bubbles inside, such as polystyrene foam.

[0110] The hanging position changing means 9 and the auxiliary hanging means 14 of the embodiment illustrated in Figures 1 to 11, the hanging position changing means 9 and the auxiliary hanging means 14 of the embodiment illustrated in Figures 12 to 15, and the hanging position changing means 9 of the embodiment illustrated in Figures 16 to 19 are not limited to the combinations illustrated above, and can be combined in any appropriate manner. For example, the hanging position changing means 9 of the embodiment illustrated in Figures 1 to 11 can be combined with the auxiliary hanging means 14 of the embodiment illustrated in Figures 12 to 15. For example, the hanging position changing means 9 of the embodiment illustrated in Figures 16 to 19 can also be used as the hanging position changing means 9 of the embodiment illustrated in Figures 12 to 15. 16 to 19, for example, it is also possible to configure the holding jig 11 (restraint jig 11d) to have insertion tools 12b as engaging parts 12, to have engaged parts 50a disposed at multiple locations on the outer peripheral surface of the upper part of the support body 50, and to have engaged parts 5a disposed as engaged parts 3b at multiple locations on the inner surface of the upper part of the sleeve tube 5. For example, it is also possible to configure the embodiments illustrated in FIGS. 1 to 11 and the embodiments illustrated in FIGS. 12 to 15 without providing auxiliary lifting means 14.

[0111] 16 to 19, the example illustrates a case in which the precast block 2 is temporarily fixed to the support body 50, and then the engaging portions 12 provided on all of the hanging position changing means 9 arranged on the closure frame body 8 are moved from the top of the support body 50 to the engaged portion 3b. However, with this construction method, for example, the engaging portions 12 provided on some of the hanging position changing means 9 of the multiple hanging position changing means 9 arranged on the closure frame body 8 can be moved from the top of the support body 50 to the engaged portion 3b, and the engaging portions 12 provided on the other hanging position changing means 9 can be left engaged with the top of the support body 50. In other words, it is also possible to connect the closure frame body 8 and the support body 50 by some of the multiple hanging position changing means 9 arranged on the closure frame body 8, and connect the closure frame body 8 and the precast block 2 by the other hanging position changing means 9.

[0112] The suspension position changing means 9 is not limited to the configuration exemplified above, and can have various other configurations as long as it has the function of the above-mentioned suspension position changing means 9. The suspension auxiliary means 14 is also not limited to the configuration exemplified above, and can have various other configurations as long as it has the function of the above-mentioned suspension auxiliary means 14. Furthermore, the structures of the engaging portion 12 provided on the suspension position changing means 9, the engaging portion 17 provided on the suspension auxiliary means 14, the engaged part 50a provided on the support body 50, and the engaged part 3b (engaged part 5a) provided on the precast block 2 are not limited to the above-mentioned embodiment, and can have various other configurations.

[0113] A major advantage of this construction method is that it minimizes or reduces the need to go under the precast blocks 2 installed on the support 50 to perform work, but it does not completely eliminate the need to go under the precast blocks 2 to perform work. For example, when visually checking that there is no gap between the bottom surface of the precast blocks 2 and the top surface of the closure frame body 8, work can be done under the precast blocks 2 as needed.

[0114] The shape and size of the superstructure 1 (precast blocks 2) are not limited to the embodiment exemplified above, and various other configurations are possible. While this embodiment illustrates the construction of a superstructure 1 fixed to a single support 50, it is also possible to construct a superstructure 1 extending across multiple supports 50 by, for example, fabricating a precast block 2 with multiple through-holes 3 and loosely inserting separate supports 50 into each through-hole 3. It is also possible to construct a superstructure 1 that is L-shaped, polygonal, or circular when viewed from above. While the embodiment exemplified above illustrates the case where the supports 50 are piles, similar construction methods and effects can be achieved even when the supports 50 are sheet piles. [Explanation of symbols]

[0115] 1 Superstructure 2 Precast blocks 3 Through holes 3a Inner circumference 3b Engaged part 4 Block letters 4a Groove 5 Sheath tube 5a Engaged tool 6 Beam members 7 Hanging hardware 8 Closure frame 8a Intervening member 8b Protrusion 9. Hanging position change means 10 Hanging members 10a Rod-shaped member 10b String-like member 11 Holding jig 11a Insertion fitting 11b Nut 11c washer 11d Restraint jig 12 Engagement portion 12a hook 12b Insert 13 Connecting part 14 Lifting aids 15 Connecting member 15a Rod-shaped member 15b String-like member 16 Connecting jig 16a Insertion fitting 16b Nut 16c washer 16d Restraint jig 17 Engagement part 17a Hook 17b Insert 18 Connection part 20 bands 21 Adhesive tape 30 Filling material 40 Divider 50 Support 50a Engaged tool 60 Impact driver 61 Fitting WB Underwater ground WL water surface position L1 (Temporarily place the closure frame) Predetermined height L2 (Planned height for installing precast blocks)

Claims

1. A method for constructing a superstructure on water, which is fixed to the top of a support erected on the bottom ground, comprising: a blocking frame body extending outward from the outer peripheral surface of the support body in a plan view is fitted onto the support body in a state in which it can move up and down relative to the support body, the lower ends of the plurality of hanging position change means are respectively connected to the upper part of the blocking frame body, and the engaging parts provided on each of the hanging position change means are engaged with the upper part of the support body, so that the blocking frame body is temporarily positioned at a predetermined height on the support body by the plurality of hanging position change means, A precast block having a through hole penetrating vertically into which the support can be loosely inserted is moved downward from above the support, and the precast block is temporarily fixed to the support in a state in which the support is loosely inserted into the through hole; a second suspending means for suspending the precast block from above the precast block, and a second suspending means for suspending the precast block from above the precast block, the second suspending means being operable from above the precast block to raise the blocking frame body from the predetermined height relative to the support body, so that the upper surface of the blocking frame body abuts against the bottom surface of the precast block, thereby sealing the gap between the outer surface of the support body and the lower end of the through hole; and a second suspending means for suspending the precast block from above the precast block, the second suspending means being operable to raise the blocking frame body from the predetermined height relative to the support body, so that the upper surface of the blocking frame body abuts against the bottom surface of the precast block, thereby sealing the gap between the outer surface of the support body and the lower end of the through hole, and a second suspending means being operable to

2. The suspension position changing means is configured by a suspension member whose lower end is connected to the upper part of the closure frame body and extends in the vertical direction, and a holding jig that is provided in the middle of the suspension member and holds the suspension member in a state where it can move relatively in the vertical direction, and the engaging portion is provided on the holding jig, When the closure frame body is temporarily placed at the predetermined height, the engaging portion is engaged with the upper portion of the support body, and the closure frame body is suspended at the predetermined height by the holding jig fixed to the upper portion of the support body via the engaging portion and the hanging member supported by the holding jig, A method for constructing an above-water superstructure as described in claim 1, wherein when the blocking frame body is raised from the predetermined height relative to the support body, the holding jig is operated to raise the blocking frame body by moving the hanging member upward relative to the holding jig, and the hanging member is fixed to the holding jig at a position where the upper surface of the blocking frame body abuts the bottom surface of the precast block.

3. a rod-shaped member having a thread groove formed therein is used as the hanging member, a metal insert having the engaging portion formed therein and through which the rod-shaped member is inserted is used as the holding jig, and a nut disposed on the metal insert and screwed into the thread groove of the rod-shaped member is used, When the closure frame is temporarily placed at the predetermined height, the closure frame is suspended at the predetermined height by the insert and the nut fixed to the upper part of the support via the engaging portion, and the rod-shaped member supported by the insert and the nut, A method for constructing an above-water superstructure as described in claim 2, wherein when the blocking frame body is raised from the predetermined height relative to the support, the nut is rotated to move the rod-shaped member upward relative to the insert and the nut, and the rotation of the nut is stopped at a position where the upper surface of the blocking frame body abuts the bottom surface of the precast block.

4. A string-like member is used as the hanging member, and a restraining jig is used as the holding jig, which is provided with the engaging portion and can switch between a restrained state and an unrestrained state of the string-like member, When the closure frame body is temporarily placed at the predetermined height, the closure frame body is suspended at the predetermined height by the restraining jig fixed to the upper part of the support body via the engaging portion and the string-like member restrained by the restraining jig, A method for constructing a superstructure above water as described in claim 2, wherein when the blocking frame body is raised from the predetermined height relative to the support body, the upper part of the string-like member is pulled upward while the restraining state of the string-like member by the restraining jig is released, thereby moving the string-like member upward relative to the restraining jig, and the string-like member is restrained by the restraining jig at a position where the upper surface of the blocking frame body abuts the bottom surface of the precast block.

5. A method for constructing an above-water superstructure as described in claim 1 or 2, wherein when the gap is blocked by the blocking frame body with the engaging portion provided on each of the lifting position change means engaged with the upper part of the support body, the engaged portion provided on the inner periphery of the through hole of the precast block and the upper part of the blocking frame body are connected by multiple lifting auxiliary means.

Images