Blocking mechanism

Abstract

This invention provides a method that enables the efficient construction of a superstructure above water without requiring complicated work below precast blocks installed on supports erected on the seabed. [Solution] The closing frame 8 is temporarily positioned by using multiple suspension position changing means 9 to fit it onto the support 50 at a predetermined height L1. The precast block 2 is temporarily fixed to the support 50 with the support 50 loosely inserted into the through hole 3 of the precast block 2, and the closing frame 8 is raised by operating each of the suspension position changing means 9 from above the precast block 2, so that the closing frame 8 comes into contact with the bottom surface of the precast block 2, and the gap between the outer surface of the support 50 and the lower end of the through hole 3 is closed by the closing frame 8. The upper structure 1 is fixed to the upper part of the support 50 by filling the space between the outer surface of the support 50 and the inner surface of the through hole 3 with filling material 30 and allowing it to solidify.

Description

Technical Field

[0001] The present invention relates to a closing mechanism. More specifically, it relates to a closing mechanism that enables efficient construction of an upper structure on water without performing complicated work below a precast block installed on a support such as a pile or sheet pile erected on the underwater ground.

Background Art

[0002] As a method of constructing an upper structure on water such as a trestle or a revetment supported by a support such as a pile or a sheet pile erected on the underwater ground, for example, there is a method in which reinforcing bars are arranged on water or in water, a formwork is then installed, and fresh concrete is placed and solidified in the formwork at the construction site. In such a method of constructing an upper structure, it is necessary to install a temporary scaffold or shoring on water or in water, assemble the reinforcing bars, and then install a formwork or pour concrete to construct it. Since there are also many complicated operations on water, there is a limit to improving the construction efficiency.

[0003] Therefore, as a method of constructing a water structure (upper structure), a precast concrete slab having a pile hole through which a pile is inserted is formed on the ground, the precast concrete slab is fixed to the pile with the head of the pile loosely inserted into the pile hole of the precast concrete slab, and a scaffold is attached around the outer circumference of the precast concrete slab (see, for example, Patent Document 1). In this construction method, the gap between the pile hole of the precast concrete slab and the outer peripheral surface of the pile is blocked with a leak-proof plate provided below the precast concrete slab, and non-shrinkage mortar is filled into the above-mentioned gap to fix the precast concrete slab to the head of the pile. However, in the construction method proposed in Patent Document 1, since the work of blocking the gap between the pile hole of the precast concrete slab and the outer peripheral surface of the pile with a leak-proof plate needs to be performed from below the precast concrete slab installed on the pile, it is necessary to install a water scaffold or for workers such as divers to enter under the precast concrete slab and perform complicated work. Therefore, there is room for improvement in improving the construction efficiency of constructing an upper structure on water and the safety of workers. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2021-107631 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] The object of the present invention is to provide a blocking mechanism that enables the efficient construction of a superstructure above water without having to perform complicated work below precast blocks installed on supports such as piles or sheet piles erected in the seabed. [Means for solving the problem]

[0006] The present invention, for achieving the above objective, is a closing mechanism used to close the gap between the support and the through-hole when fixing the superstructure to the support by filling the space between the outer surface of the support and the inner surface of the through-hole with a filling material after loosely inserting the through-hole of the superstructure into the support and temporarily fixing it, and comprising a closing frame disposed on the outer surface of the support, a suspension position changing means connected to the closing frame, and an engaging portion provided on the suspension position changing means that engages with the upper part of the support, wherein the suspension position changing means comprises a suspension member extending in the vertical direction with the engaging portion engaged with the support, and a holding jig provided in the middle of the suspension member that holds the suspension member in a state where it can move relative to the support in the vertical direction. [Effects of the Invention]

[0007] According to the present invention, the closure frame is temporarily positioned on the support at a predetermined height using multiple suspension position changing means. Then, the precast block is temporarily fixed to the support with the support loosely inserted into the through-hole of the precast block, thereby completing the installation of the precast block on the support. Next, the suspension position changing means are operated from above the precast block to raise the closure frame from the predetermined height relative to the support, so that the upper surface of the closure frame comes into contact with 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 performing complicated work below the precast block installed on the support. Subsequently, by filling the space between the outer surface of the support and the inner surface of the through-hole of the precast block with a filling material and allowing it to solidify, it becomes possible to efficiently construct the superstructure above the water without performing complicated work below the precast block installed on the support. [Brief explanation of the drawing]

[0008] [Figure 1] This is an explanatory diagram illustrating a superstructure constructed on the upper part of a support using the closure mechanism of the present invention, shown in a side view. [Figure 2] This diagram illustrates, in cross-sectional view, the closure frame in a state where it has been temporarily positioned at a predetermined height on the support using the suspension position changing means, and the precast block before it is installed on the support. [Figure 3] This is an explanatory diagram illustrating, in plan view, the closure frame body temporarily positioned at a predetermined height on the support using the suspension position changing mechanism, and the precast block before installation on the support. [Figure 4] These are explanatory diagrams illustrating the suspension position changing mechanism shown in Figures 2 and 3 in a cross-sectional view with enlarged detail. [Figure 5] Figures 2 and 3 are explanatory diagrams illustrating the suspension position changing mechanism in a magnified plan view. [Figure 6] This is an explanatory diagram illustrating, in cross-sectional view, the state in which precast blocks are installed on a support structure, as shown in Figures 2 and 3. [Figure 7] This is a view from arrow A in Figure 6. [Figure 8]This is an explanatory diagram illustrating, in cross-sectional view, the state in which the closing frame is raised from a predetermined height relative to the support, from the state shown in Figures 6 and 7, so that the upper surface of the closing frame is in contact with the bottom surface of the precast block. [Figure 9] This is an explanatory diagram illustrating, in a cross-sectional view and magnified, the situation in which a suspension member constituting a suspension position changing mechanism is moved upward using an impact driver and a fitting device. [Figure 10] This is an explanatory diagram illustrating, in cross-sectional view, the state in which the filling material is filled between the outer surface of the support and the inner surface of the through-hole in the precast block, and then solidified, starting from the state shown in Figure 8. [Figure 11] This is a view from arrow B in Figure 10. [Figure 12] This is an explanatory diagram illustrating, in cross-sectional view, a closed frame body temporarily positioned at a predetermined height on the support using a suspension position changing means of another embodiment, and a precast block before being installed on the support. [Figure 13] Figure 12 is an explanatory diagram illustrating the suspension position changing mechanism in a cross-sectional view with enlargement. [Figure 14] This is an explanatory diagram illustrating, in cross-sectional view, the state in which the precast block is installed on the support structure, as shown in Figure 12. [Figure 15] This is an explanatory diagram illustrating, in cross-sectional view, the state in which the closing frame is raised from a predetermined height relative to the support, starting from the state shown in Figure 14, so that the upper surface of the closing frame comes into contact with the bottom surface of the precast block. [Figure 16] This is an explanatory diagram illustrating another embodiment of the closure mechanism of the present invention, and is a cross-sectional view illustrating a closure frame temporarily positioned at a predetermined height on the support by a suspension position changing means, and a precast block before being installed on the support. [Figure 17] This is an explanatory diagram illustrating, in cross-sectional view, the state in which the precast block is installed on the support structure, as shown in Figure 16. [Figure 18] This is an explanatory diagram illustrating, in cross-sectional view, the state in which the connection between the upper part of the closure frame and the upper part of the support body is released by multiple suspension position changing means from the state shown in Figure 17, and the upper part of the closure frame and the precast block are connected by multiple suspension position changing means. [Figure 19]It is an explanatory diagram showing in cross-section a state where the closing frame is raised from a predetermined height with respect to the support from the state of FIG. 18 and the upper surface of the closing frame is brought into contact with the bottom surface of the precast block.

Embodiments for Carrying out the Invention

[0009] Hereinafter, the closing mechanism of the present invention will be described based on the embodiments shown in the drawings.

[0010] As illustrated in FIG. 1, the closing mechanism of the present invention is used for constructing the upper structure 1 above water that is fixed to the upper part of the support 50 driven into the underwater ground WB. Examples of the support 50 include piles such as steel pipe piles and concrete piles, and sheet piles such as steel pipe sheet piles. Examples of the upper structure unit 1 include a pier and a revetment. In the embodiments illustrated in FIGS. 1 to 11 described below, the support 50 is a steel pipe pile, and the case of constructing a concrete upper structure unit 1 on the upper part of the steel pipe pile is illustrated.

[0011] In this embodiment, the case of constructing the upper structure unit 1 fixed to the upper part of one support 50 is illustrated, but the closing mechanism can also be used for constructing the upper structure unit 1 fixed to the upper parts of two or more supports 50. The underwater upper structure unit 1 constructed using this closing mechanism is not limited to the upper structure unit 1 that is always located above the water surface position WL, and also includes the upper structure unit 1 that is temporarily partially submerged in water due to tidal fluctuations or the like.

[0012] As illustrated in FIGS, 2 and 3, the closing mechanism includes a closing frame 8, a suspension position changing means 9, and an engaging portion 12. The upper structure unit 1 is constructed using the closing mechanism and the precast block 2. The precast block 2 is formed of, for example, precast concrete, prestressed concrete, resin, etc., and is prefabricated on land or on a ship. The precast block 2 may have, for example, a reinforced concrete (steel frame reinforced concrete) structure in which reinforcing bars (or steel frames) are embedded in precast concrete or prestressed concrete, or may have a structure in which no reinforcing bars or the like are embedded in precast concrete or prestressed concrete.

[0013] The precast block 2 has a through hole 3 that extends vertically through it, into which the support 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 in this embodiment is composed of a precast concrete block body 4 in which the through hole 3 is formed, a sheath pipe 5 that extends vertically and is fitted into the through hole 3, a beam member 6 that protrudes inward from the through hole 3 in a plan view, and a suspension fitting 7.

[0014] In this embodiment, the outer shape of the block body 4 is shown as a rectangular parallelepiped, but the outer shape of the block body 4 is not limited to a rectangular parallelepiped and can be other shapes. The sheath tube 5 can be optionally provided on the precast block 2, and a precast block 2 without a sheath tube 5 can also be used. As the sheath tube 5, a resin tubular member made of fiber-reinforced plastic (FRP) or the like can be used, or a metal tubular member such as a steel pipe can be used. In this embodiment, the upper end of the sheath tube 5 is positioned lower than the upper end surface of the precast block 2. That is, there is a portion above the through hole 3 of the precast block 2 where the sheath tube 5 is not provided.

[0015] In this invention, in the area where the sheath pipe 5 of the precast block 2 is provided, the inner circumferential surface of the sheath pipe 5 is defined as the inner circumferential surface of the through hole 3. In the area where the sheath pipe 5 of the precast block 2 is not provided, the inner concrete surface of the through hole 3 is defined as the inner circumferential surface of the through hole 3.

[0016] The internal dimensions of the through-hole 3 (sheath tube 5) are set to allow the support 50 to be loosely inserted. The internal dimensions of the through-hole 3 should be set such that, 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, there is a gap (clearance) of, for example, 5 cm to 25 cm, more preferably 10 cm to 15 cm, between the inner surface of the through-hole 3 and the outer surface of the support 50.

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

[0018] As illustrated in Figure 2, the beam member 6 is positioned, for example, on top of the sheath pipe 5 or on top of the sheath pipe 5. In this embodiment, grooves for fitting each beam member 6 are formed in the upper part of the sheath pipe 5, and the beam member 6 is fitted into these grooves. For example, the beam member 6 can also be placed on top of the sheath pipe 5. The portion of the beam member 6 located inside the through hole 3 is exposed, and the portion of the beam member 6 located outside the through hole 3 is embedded in the precast concrete that constitutes the block body 4. The upper end of the beam member 6 is positioned lower than the upper end surface of the precast block 2.

[0019] Multiple lifting brackets 7 are provided on the upper part of the block body 4 for use when lifting the precast block 2 with a crane. In this embodiment, lifting brackets 7 are provided at each of the four corners of the upper part of the block body 4. The lower part of the lifting brackets 7 is embedded in the precast concrete that makes up the block body 4, and the lifting brackets 7 are integrated with the block body 4. Note that the lifting brackets 7 can be optionally provided on the precast block 2. When lifting the precast block 2 by a method other than using the lifting brackets 7, a precast block 2 without lifting brackets 7 can also be used. Although not shown in this embodiment, if ancillary structures such as mooring posts are provided on the superstructure 1, the ancillary structures such as mooring posts can be integrated with the precast block 2 (block body 4).

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

[0021] As illustrated in Figures 2 and 3, the closing frame 8 is formed in an annular shape in plan view and is fitted onto the support 50 in a manner that allows it to move vertically. The dimensions (inner diameter) of the through hole inside the closing frame 8 are set to substantially the same dimensions (outer diameter) as the outer surface dimensions (outer diameter) of the support 50. In plan view, the closing frame 8 extends outward from the outer surface of the support 50. In plan view, the closing frame 8 extends outward beyond the through hole 3 of the precast block 2. The closing frame 8 is formed from a plate-like member such as metal, resin, or wood. The thickness of the closing frame 8 can be appropriately determined depending on the material of the closing 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, a closing frame 8 with a circular outer shape in plan view is illustrated, but the outer shape of the closing frame 8 in plan view can also be other shapes such as polygonal shapes.

[0022] As illustrated in Figure 3, the closing frame 8 of this embodiment is composed of four divided members, which are obtained by dividing an annular plate-shaped member radially into four sections in a plan view. Each divided member is composed of a sector-shaped plate-shaped member with a central angle of 90 degrees in a plan view, and the closing frame 8 is formed by bringing the ends of adjacent divided members into close contact with each other. The closing frame 8 can also be configured such that each divided member is composed of a sector-shaped plate-shaped 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 vertically. The number and shape of the divided members that make up the closing frame 8 are not particularly limited, and for example, the closing frame 8 can be composed of three or fewer divided members or five or more divided members. The closing frame 8 can also be composed of, for example, a single annular plate-shaped member in a plan view.

[0023] In this embodiment, an intervening member 8a is provided on the inner surface of the closing frame 8 that abuts the outer surface of the support 50 to enhance the adhesion between the outer surface of the support 50 and the inner surface of the closing frame 8. The intervening member 8a, which enhances the adhesion between the outer surface of the support 50 and the inner surface of the closing frame 8, can also be provided on the outer 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 commonly used in packing for the intervening member 8a. The intervening member 8a may be either a solid or hollow body, but it is more preferable to be solid. It is preferable that the dimensions (outer diameter) of the outer surface of the support 50 and the dimensions (inner diameter) of the inner surface of the intervening member 8a are substantially the same.

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

[0025] As illustrated in Figures 2 and 3, in this construction method using the closure mechanism, a plurality of suspension position changing means 9 are used as means to suspend the closure frame 8 from the support 50. The lower end of the suspension position changing means 9 is connected to the upper part of the closure frame 8. The suspension position changing means 9 is provided with an engaging portion 12 that can engage with the upper part of the support 50. In this embodiment, the suspension position changing means 9 consists of a suspension member 10 whose lower end is connected to the upper part of the closure frame 8 and extends in the vertical direction, and a holding jig 11 provided in the middle of the suspension member 10 to hold the suspension member 10 in a state where it can move relative to the suspension member 10 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 suspension member 10 in this embodiment is composed of a metal rod-shaped member 10a with screw threads. As the rod-shaped member 10a, for example, a known separator used in the construction of concrete formwork can be used. The suspension member 10 (rod-shaped member 10a) extends upward from the upper part of the closing frame 8. In this embodiment, the upper part of the closing frame 8 and the lower end of the suspension member 10 are connected via a connecting part 13. The connecting part 13 in this embodiment is configured to allow for variable angle (direction) of extension of the suspension member 10 relative to the closing frame 8. The connecting part 13 that allows for variable angle (direction) of extension of the suspension member 10 can be formed from, for example, an elastic material such as rubber or a flexible resin. The method of connecting the lower end of the suspension member 10 to the upper part of the closing frame 8 is not particularly limited; for example, the upper part of the closing frame 8 and the lower end of the suspension member 10 can be connected via a connector that allows for changing the angle of extension of the suspension member 10. For example, the lower end of the suspension member 10 can be fixed to the upper part of the closing frame 8 by welding or other means.

[0027] The holding jig 11 in this embodiment is composed of a through fitting 11a through which the rod-shaped member 10a is inserted, and a nut 11b positioned on the through fitting 11a and screwed into the screw groove of the rod-shaped member 10a. The through fitting 11a is composed of a cylindrical fitting having a through hole with approximately the same dimensions as the diameter of the rod-shaped member 10a. No screw groove is provided on the inner surface of the through hole of the through fitting 11a. The through fitting 11a and the nut 11b are not joined together. In this embodiment, a washer 11c through which the rod-shaped member 10a is inserted is interposed between the upper end of the through fitting 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 composed of a hook 12a that can be hooked onto the upper part (upper edge) of the support body 50 (steel pipe pile). The hook 12a can be formed, for example, by bending a reinforcing bar into a roughly U-shape. The engaging portion 12 (hook 12a) is joined to the side surface of the holding jig 11 (insertion fitting 11a). By engaging the engaging portion 12 with the upper part of the support body 50, the holding jig 11 (insertion fitting 11a) can be fixed to the upper part of the support body 50. Then, the closing frame 8 can be suspended from the support body 50 by the holding jig 11 (insertion fitting 11a) fixed to the upper part of the support body 50 via the engaging portion 12, and the suspension member 10 (rod-shaped member 10a) supported by the holding jig 11 (insertion fitting 11a, nut 11b).

[0029] As illustrated in Figure 3, in this embodiment, multiple suspension position changing means 9 are arranged at intervals from each other so as to surround the outside of the insertion hole of the closing frame 8 in a plan view. Suspension position changing means 9 are provided at multiple locations on each of the divided members that make up the closing frame 8. When the closing frame 8 is formed, it is preferable to arrange the multiple suspension position changing means 9 so that the distance between adjacent suspension position changing means 9 (lower ends of the suspension members 10) is equal. As illustrated in Figure 3, in this embodiment, suspension position changing means 9 are provided at 12 locations on the closing frame 8, but the number and arrangement of suspension position changing means 9 provided on the closing frame 8 can be appropriately determined according to the size and weight of the closing frame 8.

[0030] In this embodiment, each divided member constituting the closing frame 8 is provided with a projection 8b extending toward the adjacent divided member on its lower surface. When the closing frame 8 is formed by four divided members suspended by a plurality of suspension position changing means 9, the projections 8b on each divided member allow adjacent divided members to support each other's load. The projections 8b can be provided as needed.

[0031] As illustrated in Figures 2 and 3, in this embodiment, a plurality of suspension assisting means 14 are used as means to suspend the closing frame 8 from the precast block 2. The suspension assisting means 14 in this embodiment consists of a connecting member 15 whose lower end is connected to the upper part of the closing frame 8 and extends in the vertical direction, and a connecting jig 16 which engages with the sheath pipe 5 and fixes 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 circumference 3a of the through hole 3 of the precast block 2. In this embodiment, the upper end of the sheath pipe 5 is the engaged portion 3b, and the engaging portion 17 is configured to engage with the upper end of the sheath pipe 5. Figures 2 and 3 show the connecting member 15 and the connecting jig 16 provided with the engaging portion 17 separated.

[0032] In this embodiment, the connecting member 15 and the connecting jig 16 constituting the suspension assisting means 14 are made of the same material as the suspension member 10 and the holding jig 11 constituting the suspension position changing means 9. Furthermore, the engaging portion 17 provided on the suspension assisting means 14 is made of the same material as the engaging portion 12 provided on the suspension position changing means 9. The connecting member 15, like the suspension member 10, is made of a metal rod-shaped member 15a with screw threads. The connecting member 15 (rod-shaped member 15a) extends upward from the upper part of the closing frame 8. In this embodiment, the upper part of the closing 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 allow for variable angle (direction) of extension of the connecting member 15 relative to the closing frame 8. The connecting portion 18, which allows for variable angle (direction) of extension of the connecting member 15, can be formed from, for example, an elastic material such as rubber or a flexible resin. The method of connecting the lower end of the connecting member 15 to the upper part of the closing frame 8 is not particularly limited. For example, the upper part of the closing frame 8 and the lower end of the connecting member 15 can be connected via a connector that allows the angle at which the connecting member 15 extends to be changed. For example, the lower end of the connecting member 15 can be fixed to the upper part of the closing 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 that allows relative movement in the vertical direction. Similar to the holding jig 11, the connecting jig 16 of this embodiment is configured to have a through fitting 16a through which the rod-shaped member 15a can be inserted, and a nut 16b that is positioned on the through fitting 16a and can be screwed into the screw groove of the rod-shaped member 15a. The through fitting 16a is a cylindrical fitting having a through hole that is approximately the same size as the diameter of the rod-shaped member 15a. No screw groove is provided on the inner surface of the through hole of the through fitting 16a. The through fitting 16a and the nut 16b are not joined together. In this embodiment, a washer 16c through which the rod-shaped member 15a can be inserted is interposed between the upper end of the through fitting 16a and the lower end of the nut 16b. The washer 16c can be provided as needed.

[0034] In this embodiment, the engaging portion 17 is composed of a hook 17a that can be hooked onto the upper end (edge) of the sheath tube 5. In this embodiment, a groove 4a is provided on the outside of the sheath tube 5, allowing the engaging portion 17 to be engaged with the upper end (edge) of the sheath tube 5 that constitutes the engaged portion 3b. The engaging portion 17 (hook 17a) is joined to the side surface of the connecting jig 16 (insertion fitting 16a). By engaging the engaging portion 17 (hook 17a) with the engaged portion 3b (upper end of the sheath tube 5) provided on the inner circumference 3a of the through hole 3 of the precast block 2, the connecting jig 16 (insertion 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 parts 18 constituting multiple suspension support means 14 are arranged so as to surround the outside of the insertion hole of the closing frame 8 in a plan view. In a plan view, the multiple suspension support means 14 (connecting members 15) are arranged on the outside of the multiple suspension position changing means 9 (suspension members 10). Connecting members 15 are arranged at multiple locations on each of the divided members constituting the closing frame 8. When the closing frame 8 is formed, it is preferable to arrange the multiple suspension support means 14 so that the distance between adjacent suspension support means 14 (lower ends of connecting members 15) is equal. In this embodiment, suspension support means 14 are provided at 12 locations on the closing frame 8, but the number and arrangement of suspension support means 14 provided on the closing frame 8 can be appropriately determined according to the size and weight of the closing frame 8. Suspension support means 14 can be provided arbitrarily as needed.

[0036] The following describes the specific work procedure for constructing the superstructure 1 using the closure mechanism.

[0037] As illustrated in Figures 2 and 3, the precast blocks 2, the closing frame 8, and the components constituting the suspension position changing means 9 are manufactured in advance on land or on a ship to match the size of the support 50 that will construct the superstructure 1. Then, the precast blocks 2, the closing frame 8, and the components constituting the suspension position changing means 9 and the engaging part 12 are transported by a workboat equipped with a crane to the construction area where the support 50 is erected. If the suspension assisting means 14 is used, the components constituting the suspension assisting means 14 and the engaging part 17 are also manufactured in advance on land or on a ship and transported to the construction area.

[0038] In this embodiment, suspension position changing means 9 are arranged at multiple locations on the upper part of the divided members constituting the closure frame 8 on a workboat or the like. Specifically, the lower ends of the suspension members 10 (rod-shaped members 10a) constituting each suspension position changing means 9 are connected to the upper part of the divided members constituting the closure frame 8 by connecting parts 13. Then, the insertion fitting 11a constituting the holding jig 11 is inserted through the upper part of the rod-shaped member 10a, which is the suspension member 10, and a washer 11c is placed on top of the insertion fitting 11a. Then, a nut 11b is screwed 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 top of the washer 11c. An engagement part 12 (hook 12a) is attached to the side of the holding jig 11 (insertion fitting 11a).

[0039] When using the suspension support means 14, the lower end of the connecting member 15 (rod-shaped member 15a) constituting the suspension support means 14 is connected to the upper part of the divided member constituting the closing frame body 8 by the connecting part 18. The connecting jig 16 (insertion fitting 16a, nut 16b, and washer 16c) constituting the suspension support means 14 is kept separate from the connecting member 15. The engaging part 17 is attached to the side surface of the connecting jig 16 (insertion fitting 16a).

[0040] As illustrated in Figure 3, multiple suspension position changing means 9 are arranged in a plan view so as to surround the outside of the insertion hole of the closing frame 8, and connecting members 15 and connecting parts 18 constituting the suspension assisting means 14 are arranged in a plan view so as to surround the outside of the closing frame 8, and connecting members 15 and connecting parts 18 constituting the suspension assisting means 14 are arranged in a multiple location on the outside of the closing frame 8 (divided member). The work of arranging the suspension position changing means 9 and the connecting members 15 and connecting parts 18 constituting the suspension assisting means 14 on land or on a ship before heading to the construction water area, or it may be done on a work vessel in the construction water area.

[0041] As illustrated in Figures 2 and 3, during construction work in the construction water area where the superstructure 1 is to be built, the closure frame 8 is fitted onto the support 50 in a state that allows it to move vertically, the lower ends of the multiple suspension position changing means 9 are connected to the upper part of the closure frame 8, and the engaging parts 12 provided on each suspension position changing means 9 are engaged with the upper part of the support 50, thereby temporarily positioning the closure frame 8 at a predetermined height L1 of the support 50 using the multiple suspension position changing means 9. That is, the closure frame 8 is suspended from the support 50 using the multiple suspension position changing means 9. The predetermined height L1 (height of the upper surface of the closure frame 8) where the closure frame 8 is temporarily positioned is set lower than the planned height L2 where the bottom surface of the precast block 2 (block body 4) to be installed on the support 50 later will be positioned. The distance H between the predetermined height L1 and the planned height L2 mentioned above should be set to, for example, 50 mm or more and 200 mm or less. In Figure 2, the predetermined height L1 is shown by a dashed line, and the planned height L2 is shown by a dotted line.

[0042] More specifically, in this embodiment, when temporarily positioning the closing frame 8 at a predetermined height L1, the engaging portions 12 of the multiple suspension position changing means 9, which are arranged on each of the divided members constituting the closing frame 8, are engaged with the upper part of the support 50. Then, the holding jig 11, which is fixed to the upper part of the support 50 via the engaging portions 12, and the suspension member 10, which is supported by the holding jig 11, are used to suspend each of the divided members constituting the closing frame 8 at the predetermined height L1.

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

[0044] The length of the suspension member 10 extending between the retaining jig 11 (insertion fitting 11a) and the connecting part 13 is adjusted so that the closing frame 8 is positioned at a predetermined height L1 when the engaging part 12 is engaged with the support 50. In this embodiment, when the nut 11b is rotated in one direction on the insertion 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 fitting 11a and washer 11c, the rod-shaped member 10a moves downward relative to the nut 11b. Therefore, by rotating the nut 11b and adjusting the length of the rod-shaped member 10a extending between the retaining jig 11 and the connecting part 13, the height position of the closing frame 8 can be adjusted.

[0045] The inner surfaces of each divided member constituting the closing frame 8 (the inner surfaces of the intervening member 8a) are in contact with the outer surface of the support 50. Each divided member is arranged so that there are no gaps between adjacent divided members. In this embodiment, the protrusions 8b provided on the lower surface of each divided member are positioned below the lower surfaces of adjacent divided members, so that the divided members support each other's loads via the protrusions 8b.

[0046] When the closure frame 8 is composed of a single annular plate-shaped member in plan view, the closure frame 8, with multiple suspension position changing means 9 installed, is moved downward from above to fit onto the support 50, and the engaging portions 12 provided on each suspension position changing means 9 are engaged with the upper part of the support 50. Then, the height position of the closure frame 8 is adjusted to a predetermined height L1 using the suspension position changing means 9.

[0047] As illustrated in Figures 2 and 3, before the precast block 2 is installed on the support 50, the upper end of the connecting member 15 constituting the suspension support means 14 is a free end. If the connecting member 15 is tilted outward, it may hinder the subsequent installation of the precast block 2 on the support 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 tilt inward toward the support 50. For example, an annular rubber member or a string-like member can be used as the band 20.

[0048] Furthermore, during work in the construction water area, a partition plate 40 is provided at a predetermined depth from the upper end of the support 50 to divide the interior of the support 50 vertically. The outer dimensions of the partition plate 40 are set to be approximately the same as the inner dimensions of the support 50. The method of installing the partition plate 40 inside the support 50 is not particularly limited, but for example, the partition plate 40 can be fixed inside the support 50 by supporting it with a suspension member such as a wire suspended from the upper end of the support 50.

[0049] Since the closure frame 8 equipped with multiple lifting position changing means 9 is relatively lightweight, it can be lifted by one or a few workers. Therefore, the closure frame 8 equipped with multiple lifting position changing means 9 can be moved to the vicinity of the support 50 using a small boat (or raft) floating on the water, and workers can manually temporarily position the closure frame 8 at a predetermined height L1 on the support 50 from the boat. The installation work of the closure frame 8 and lifting position changing means 9 on the support 50 can also be performed, for example, using a crane on a workboat.

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

[0051] In this embodiment, by placing the beam member 6, which protrudes inward from the through-hole 3, on the upper end of the support 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 upper part of the support 50. When the precast block 2 is temporarily fixed to the upper part of the support 50, workers can stand on the precast block 2 and perform work. In this state, the temporarily positioned closing frame 8 is positioned at a predetermined height L1, which is lower than the planned height L2 where the bottom surface of the precast block 2 (block body 4) is positioned, and the upper surface of the closing frame 8 and the bottom surface of the precast block 2 are separated.

[0052] When using the suspension support means 14, the band 20 that bundled the connecting members 15 constituting each suspension support means 14 is removed. Next, a connecting jig 16 is attached to the upper part of each connecting member 15, and the connecting jig 16 is engaged with the engaged portion 3b (upper end of the sheath pipe 5) provided on the inner circumference 3a of the through hole 3 of the precast block 2 by the engaging portion 17. Then, 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 connect the closing frame 8 and the engaged portion 3b. As a result, the closing frame 8 is suspended from the precast block 2 (block body 4) by the connecting jig 16 (insertion 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 fitting 16a, nut 16b).

[0053] More specifically, in this embodiment, the connecting member 15, which is a rod-shaped member 15a, has a through fitting 16a and a washer 16c inserted through its upper part, and the hook 17a attached to the through fitting 16a is hooked onto the edge of the upper end of the sheath 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 so that the nut 16b is placed on top of the washer 16c.

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

[0055] As illustrated in Figure 7, each of the suspension position changing means 9 and suspension assisting means 14 is positioned in a location that avoids the beam member 6 in a plan view. When the precast block 2 is temporarily fixed to the support 50, the center of the support 50 and the center of the through hole 3 in the precast block 2 may be misaligned in a plan view. In this case as well, the connecting member 15 (rod-shaped member 15a) constituting each of the suspension assisting means 14 can absorb the misalignment by tilting or bending in accordance with the misalignment between the support 50 and the precast block 2. In this embodiment, the lower end of the connecting member 15 and the upper part of the closing frame 8 are connected via a connecting part 18 that can change the angle (direction) of the connecting member 15, so the connecting member 15 tilts in accordance with the misalignment between the support 50 and the precast block 2, which is advantageous in reducing the load on the connecting member 15.

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

[0057] In this embodiment, an example is shown in which each suspension position changing means 9 is operated from above the precast block 2 with the engaging portion 12 provided on each suspension position changing means 9 engaged with the upper part of the support 50. In this case, the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2 is closed by the closing frame 8, and the closing frame 8 is fixed to the support 50 by the multiple suspension position changing means 9. The case in which the engaging portion 12 provided on each suspension position changing means 9 is engaged with the engaged portion 3b provided on the inner circumference 3a of the through hole 3 of the precast block 2 before operating the suspension position changing means 9 will be explained in another embodiment which will be illustrated later.

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

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

[0060] More specifically, the nuts 11b constituting each holding jig 11 are rotated on the insertion fitting 11a and washer 11c from above the precast block 2, thereby moving the rod-shaped member 10a upward relative to the insertion fitting 11a, washer 11c and nut 11b. Furthermore, the nuts 16b constituting each connecting jig 16 are rotated on the insertion fitting 16a and washer 16c from above the precast block 2, thereby moving the rod-shaped member 15a upward relative to the insertion fitting 16a, washer 16c and nut 16b. Finally, the rotation of the respective nuts 11b and 16b is stopped when the upper surface of the closing frame 8 contacts the bottom surface of the precast block 2.

[0061] If the amount of lifting of each suspension member 10 and connecting member 15 becomes large during the process of raising the closing frame 8, the load and distortion on the suspension position changing means 9, the suspension assisting means 14, and the closing frame 8 will increase. Therefore, it is preferable to gradually raise each suspension member 10 and connecting member 15 in a balanced manner by sequentially changing the suspension member 10 and connecting member 15 being raised so that the amount of lifting of each suspension member 10 and connecting member 15 is approximately equal. In this embodiment, the amount of lifting of each suspension member 10 and connecting member 15 can be finely adjusted by adjusting the amount of rotation of each nut 11b and 16b.

[0062] The nut 11b that constitutes the holding jig 11 can be rotated by hand by the operator, but as illustrated in Figure 9, the nut 11b can be rotated more efficiently by using an impact driver 60 and a fitting device 61. A known impact driver 60 used for fastening screws and bolts can be used. The fitting device 61, which is made to match the shape of the nut 11b, is attached to the rotating shaft of the impact driver 60, to which the bit is normally attached. The fitting device 61 is made of a cylindrical member that extends in the vertical direction, and is structured so that the nut 11b can be fitted into the lower end of the fitting device 61.

[0063] As illustrated in Figure 9, the nut 11b is fitted into the lower end of the fitting device 61, and the upper part of the rod-shaped member 15a, which extends above the nut 11b, is inserted into the internal part of the fitting device 61. Then, the fitting device 61 is rotated together with the rotation axis of the impact driver 60, thereby rotating the nut 11b. A drill driver can also be used instead of the impact driver 60. When the nut 11b is rotated and the rod-shaped member 15a is moved upward relative to the connecting jig 16, the length of the portion of the rod-shaped member 15a that extends above the nut 11b becomes longer. Therefore, it is preferable to set the longitudinal (vertical) dimension of the fitting device 61 to be longer than the distance H between the predetermined height L1 and the planned height L2 described above. If the longitudinal (vertical) dimension of the fitting device 61 is to be shorter than the separation distance H, the process of raising the rod-shaped member 15a can be temporarily interrupted, and the upper part of the rod-shaped member 15a that extends above the nut 11b can be cut off. Similarly, the nut 16b that constitutes the connecting jig 16 can also be rotated efficiently using the impact driver 60 and the fitting device 61.

[0064] After fixing the closing frame 8 to the support 50, as illustrated in Figures 10 and 11, with the closing frame 8 sealing the gap between the outer surface of the support 50 and the lower end of the through-hole 3 in the precast block 2, the filling material 30 is filled from above the precast block 2 between the outer surface of the support 50 and the inner surface of the through-hole 3. More specifically, the filling material 30 is filled inside the support 50 above the partition plate 40, in the gap between the outer surface of the support 50 above the closing frame 8 and the inner surface of the through-hole 3, and above the through-hole 3 above the support 50. Examples of the filling material 30 include ready-mix concrete and a liquid resin that solidifies after curing. In Figures 10 and 11, the areas where the filling material 30 is filled are indicated by shaded lines.

[0065] During the process of filling with the filling material 30, the load of the filling material 30 is applied to the closing frame 8, but this load is supported by multiple suspension position changing means 9. If suspension support means 14 are provided, the load of the filling material 30 is also supported by multiple suspension support means 14. As a result, the closing frame 8 maintains a state in which the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2 is sealed.

[0066] Afterward, the filling material 30 is allowed to cure for a predetermined period to solidify, thereby fixing the superstructure 1, which integrates the precast block 2 and the solidified filling material 30, to the top of the support 50. With this, the construction of the superstructure 1 is completed. Each of the suspension position changing means 9 and suspension assisting means 14 becomes embedded in the filling material 30. The closing frame 8 becomes part of the superstructure 1. The suspension fittings 7 may be removed from the superstructure 1 or left in place.

[0067] As described above, in this construction method using the closure mechanism, the closure frame 8 is fitted onto the support 50 in a state that allows it to move vertically, the lower ends of the multiple suspension position changing means 9 are connected to the upper part of the closure frame 8, and the engaging parts 12 provided on each suspension position changing means 9 are engaged with the upper part of the support 50, thereby temporarily positioning the closure frame 8 at a predetermined height L1 of the support 50 using the multiple suspension position changing means 9. Then, the precast block 2 having a through hole 3 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, thereby completing the installation of the precast block 2 on the support 50.

[0068] Subsequently, with the engaging portion 12 provided on each suspension position changing means 9 engaged with either the upper part of the support 50 or the engaged portion 3b provided on the inner circumference 3a of the through hole 3 of the precast block 2, the suspension position changing means 9 are operated from above the precast block 2 to raise the closing frame 8 from a predetermined height L1 relative to the support 50. Then, the upper surface of the closing frame 8 is brought into contact with the bottom surface of the precast block 2, and the closing frame 8 closes the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2. This allows the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2 to be closed by the closing frame 8 without having to perform complicated work below the precast block 2 installed on the support 50. Multiple suspension position changing means 9 effectively suppress distortion and tilting of the closing frame 8, as well as the formation of gaps between the bottom surface of the precast block 2 and the closing frame 8, by pressing the top surface of the closing frame 8 against the bottom surface of the precast block 2.

[0069] Subsequently, by filling the space between the outer surface of the support 50 and the inner surface of the through-hole 3 of the precast block 2 with the filling material 30 and allowing it to solidify, the superstructure 1 above the water can be efficiently constructed without performing complicated work beneath the precast block 2 installed on the support 50. This construction method does not require diving or working on the water beneath the precast block 2 installed on the support 50, thus improving the construction efficiency and worker safety of the superstructure 1 above the water.

[0070] For example, if the suspension position changing means 9 is not provided with an engaging portion 12 and is joined to the upper part of the support 50 by welding or adhesive, a lot of time will be required to fix the suspension position changing means 9 to the upper part of the support 50, and complicated work will need to be performed on the precast block 2. If welding is performed, there is also a risk that molten metal will fall onto the closing frame 8 and damage the closing frame 8. In contrast, if the suspension position changing means 9 is provided with an engaging portion 12, complicated work will not need to be performed on the precast block 2, and the suspension position changing means 9 can be easily fixed to the upper part of the support 50 with fewer work steps. Therefore, by providing the suspension position changing means 9 with an engaging portion 12, the work efficiency of constructing the superstructure 1 can be improved.

[0071] As in this embodiment, the suspension position changing means 9 can be simplified by configuring it with a suspension member 10 whose lower end is connected to the upper part of the closing frame 8, and a holding jig 11 that holds the suspension member 10 in a state where it can move relative to the vertical, and by providing an engaging portion 12 on the holding jig 11. In the operation of temporarily positioning the closing frame 8 at a predetermined height L1, the closing frame 8 can be suspended at the predetermined height L1 simply by engaging the engaging portion 12 with the upper part of the support 50 and fixing it in place, using the engaging portion 12, the holding jig 11, and the suspension member 10. Therefore, the operation of temporarily positioning the closing frame 8 at a predetermined height L1 can be performed easily and efficiently. Furthermore, by operating the holding jig 11 from above the precast block 2 and moving the suspension member 10 upward relative to the holding jig 11, the closing frame 8 can be raised relative to the support 50. Therefore, the operation of bringing the upper surface of the closing frame 8 into contact with the bottom surface of the precast block 2 can also be performed easily and efficiently.

[0072] As in this embodiment, by using a rod-shaped member 10a with a screw groove as the suspension member 10, and using an insertion fitting 11a with an engaging portion 12 and a nut 11b that screws into the screw groove of the rod-shaped member 10a as the holding jig 11, the suspension position changing means 9 can be constructed very simply. In the operation of raising the closing frame 8 from a predetermined height L1, the worker does not need to lift the rod-shaped member 10a by hand, and the rod-shaped member 10a can be raised simply by rotating the nut 11b, so the closing frame 8 can be easily raised with fewer workers.

[0073] Furthermore, by adjusting the amount of rotation (number of rotations) of the nut 11b, the amount of upward movement of the rod-shaped member 10a can be finely adjusted, allowing multiple rod-shaped members 10a provided on the closing frame 8 to be raised in a balanced manner. When the closing frame 8 is in contact with the bottom surface of the precast block 2, the nut 11b becomes difficult to rotate, so it is easy to determine from above the precast block 2 whether or not the closing frame 8 is in contact with the bottom surface of the precast block 2, and the closing frame 8 can be pressed against the bottom surface of the precast block 2 with an appropriate force. Therefore, it is advantageous to reduce the risk of excessive load or distortion on the suspension position changing means 9 and the closing frame 8, and is advantageous for stably sealing the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2 with the closing frame 8.

[0074] In this embodiment, with the engaging portion 12 provided on each suspension position changing means 9 engaged with the upper part of the support 50, the gap between the bottom surface of the precast block 2 and the upper surface of the closing frame 8 is closed by the closing frame 8. In this case, if the engaged portion 3b provided on the inner circumference 3a of the through hole 3 of the precast block 2 and the upper part of the closing frame 8 are connected by multiple suspension support means 14, the load of the closing frame 8 and the filling material 30 can be supported not only by the multiple suspension position changing means 9 but also by the multiple suspension support means 14. Furthermore, the load of the closing frame 8 and the filling material 30 can be distributed not only to the support 50 but also to the precast block 2. Moreover, since the position of the closing frame 8 close to the area that contacts the bottom surface of the precast block 2 can be suspended by the multiple suspension support means 14, the separation between the upper surface of the closing frame 8 and the bottom surface of the precast block 2 can be effectively suppressed. Therefore, the closing frame 8 is more advantageous for stably sealing the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2.

[0075] Furthermore, as in this embodiment, by using a precast block 2 in which a sheath tube 5 constituting the through hole 3 is fitted, and by configuring the engaged portion 3b to be the upper end of the sheath tube 5, and engaging the engaging portion 17 provided on the suspension assisting means 14 with the upper end of the sheath tube 5, the suspension assisting means 14 can be connected to the precast block 2 very easily.

[0076] The suspension assisting means 14 can be simplified by comprising a connecting member 15 whose lower end is connected to the upper part of the closing frame 8, and a connecting jig 16 that holds the connecting member 15 in a state where it can move relative to it in the vertical direction, and by providing an engaging portion 17 on the connecting jig 16. In this embodiment, when temporarily positioning the closing frame 8 at a predetermined height L1, the engaging portion 17 is engaged with the upper part of the sheath pipe 5 and fixed in place, and the closing 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 closing frame 8 to be supported not only by the multiple suspension position changing means 9 but also by the multiple suspension assisting means 14. When raising the closure frame 8 from a predetermined height L1, the connecting jig 16 of the suspension assisting means 14 is operated in conjunction with the operation of the suspension position changing means 9 to move the connecting member 15 upward relative to the connecting jig 16, thereby effectively suppressing tilting or distortion of the closure frame 8 during the raising process.

[0077] For example, if the connecting jig 16 is not provided with an engaging portion 17 and is joined to the sheath pipe 5 by welding or adhesive, a lot of time is required to fix the connecting jig 16 to the sheath pipe 5, and complicated work must be performed on the precast block 2. If welding is performed, there is also a risk that molten metal will fall onto the closing frame 8 and damage the closing frame 8. In contrast, if the connecting jig 16 is provided with an engaging portion 17, complicated work on the precast block 2 is not required, and the connecting jig 16 can be easily fixed to the sheath pipe 5 with fewer work steps.

[0078] Furthermore, as in this embodiment, by using a rod-shaped member 15a with a screw groove as the connecting member 15, and using a through fitting 16a with an engaging portion 17 and a nut 16b that screws into the screw groove of the connecting member 15 as the connecting jig 16, the lifting assisting means 14 can be constructed very simply. In the operation of raising the closing frame 8 from a predetermined height L1 relative to the support 50, the worker does not need to lift the rod-shaped member 15a by hand, and the rod-shaped member 15a can be raised simply by rotating the nut 16b, so the closing frame 8 can be easily raised with fewer workers.

[0079] Furthermore, by adjusting the amount of rotation (number of rotations) of the nut 16b, the amount of upward movement of the rod-shaped member 15a can be finely adjusted, allowing multiple rod-shaped members 15a provided on the closing frame 8 to be raised in a balanced manner. When the closing frame 8 is in contact with the bottom surface of the precast block 2, the nut 16b becomes difficult to rotate, so it is easy to determine from above the precast block 2 whether or not the closing frame 8 is in contact with the bottom surface of the precast block 2, and the closing frame 8 can be pressed against the bottom surface of the precast block 2 with an appropriate force. Therefore, it is advantageous to reduce the risk of excessive load or distortion on the suspension assisting means 14, the suspension position changing means 9, and the closing frame 8, and is more advantageous for stably sealing the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2 with the closing frame 8.

[0080] In this embodiment, the suspension position changing means 9 and the suspension assisting means 14 are provided at 12 locations on the closing frame 8. However, the number and arrangement of the suspension position changing means 9 and the suspension assisting means 14 provided on the closing frame 8 can be appropriately determined according to the size and weight of the closing frame 8. It is preferable that the number of locations for each of the suspension position changing means 9 and the suspension assisting means 14 provided on the closing frame 8 be between 8 and 16. Arranging the suspension position changing means 9 and the suspension assisting means 14 at 8 to 16 locations on the closing frame 8 is advantageous for stably closing the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2 with the closing frame 8, while relatively reducing the amount of work required to operate the suspension position changing means 9 and the suspension assisting means 14.

[0081] In this embodiment, the upper end of the sheath pipe 5 provided in the precast block 2 is shown as the engaged portion 3b. However, for example, instead of providing the sheath pipe 5 in the precast block 2, a groove or fitting that can engage with the engaging portion 17 provided in the suspension assisting means 14 can be provided on the concrete surface of the inner circumference 3a of the through hole 3 in the precast block 2, which serves as the engaged portion 3b.

[0082] As in this embodiment, when manufacturing the precast block 2, if a beam member 6 is provided that protrudes inside the through hole 3 of the precast block 2, the precast block 2 can be easily and stably temporarily fixed to the upper part of the support 50 by placing the beam member 6 on the upper end of the support 50. After the precast block 2 is temporarily fixed to the upper part of the support 50, workers can stand on the precast block 2 and 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 embodiments exemplified above. For example, the number of beam members 6 protruding into the through-hole 3 can be one or three or more. Also, for example, the ends of the beam members 6 can be positioned inside the through-hole 3 in a plan view, so that the beam members 6 do not cross the through-hole 3. Furthermore, for example, two beam members 6 can be arranged side by side inside the through-hole 3 in a plan view.

[0084] In this closure mechanism, the suspension member 10 and holding jig 11 constituting the suspension position changing means 9, the engaging portion 12 provided on the suspension position changing means 9, the connecting member 15 and connecting jig 16 constituting the suspension assisting means 14, and the engaging portion 17 provided on the suspension assisting means 14 can be configured as illustrated in Figures 12 to 15. The functions of the suspension position changing means 9, the engaging portion 12, the suspension assisting means 14, and the engaging portion 17 are the same as those of the embodiments illustrated in Figures 1 to 11. The other components of the closure mechanism are the same as those of the embodiments illustrated in Figures 1 to 11.

[0085] As illustrated in Figure 12, in this embodiment, a string-like member 10b is used as the suspension member 10 constituting the suspension position changing means 9, and a restraining jig 11d that can switch between a restrained state and an unrestrained state of the string-like member 10b is used as the holding jig 11. The holding jig 11 (restraining jig 11d) is provided with an insertion tool 12b as an engaging portion 12. Also, similar to the suspension position changing means 9, a string-like member 15b is used as the connecting member 15 constituting the suspension assisting means 14, and a restraining jig 16d that can switch between a restrained state and an unrestrained state of the string-like member 15b is used as the connecting jig 16. The connecting jig 16 (restraining jig 16d) is provided with an insertion tool 17b as an engaging portion 17.

[0086] The string-like members 10b and 15b can be made of, for example, wire, wire rope, resin rope or string, or belt. For the restraint fixtures 11d and 16d, for example, known ratchets used for fall prevention in mountaineering can be used. The restraint fixture 11d (16d) in this embodiment has a self-locking function (automatic tightening function) in which the string-like members 10b (15b) inserted through the restraint fixture 11d (16d) can move to one side relative to the restraint fixture 11d (16d) but not to the other side.

[0087] As illustrated in Figures 12 and 13, when temporarily positioning the closing frame 8 at a predetermined height L1, the closing frame 8 is suspended at the predetermined height L1 by a restraining jig 11d fixed to the upper part of the support 50 via an engaging portion 12, and by a string-like member 10b restrained by the restraining jig 11d. More specifically, in this embodiment, the lower ends of the string-like member 10b are connected to the ring-shaped connecting portions 13 provided at multiple locations on the upper part of the closing frame 8, and the lower ends of the string-like member 15b are connected to the ring-shaped connecting portions 18 provided at multiple locations on the upper part of the closing frame 8. In this embodiment, engaging devices 50a are provided at multiple locations on the outer circumferential surface of the upper part of the support 50. The restraining jig 11d is fixed to the upper part of the support 50 by engaging (inserting) the insertion device 12b provided on the restraining jig 11d into the engaging devices 50a.

[0088] The middle portion of the string-like member 10b is inserted through the restraint jig 11d, and the string-like member 10b extending between the restraint jig 11d and the connecting portion 13 is tensed (stretched), thereby restraining the middle portion of the string-like member 10b with the restraint jig 11d. That is, the restraint jig 11d, which is fixed to the upper part of the support body 50 via the insertion device 12b, and the string-like member 10b, which is supported by the restraint jig 11d, suspend the closing frame body 8 from the support body 50. The upper part of the string-like member 10b protruding from the upper part of the restraint jig 11d is left hanging inside the support body 50.

[0089] When the closure frame 8 is temporarily positioned at a predetermined height L1, it is preferable 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, the precast block 2 does not have a groove 4a, and instead, multiple engaging parts 5a are provided at multiple locations on the inner surface of the upper part of the sheath tube 5 as engaging parts 3b, which can engage with the engaging part 17 (insertion part 17b) provided on the suspension assisting means 14.

[0090] As illustrated in Figure 14, after the precast block 2 is installed and temporarily fixed to the support 50, the adhesive tape 21 that was bonding the restraint jig 11d and the string-like member 15b is removed. Next, the middle of each string-like member 15b is inserted into the restraint jig 16d that constitutes the connecting jig 16. Then, the insertion device 17b provided on the restraint jig 16d is engaged (inserted) with the engaging device 5a provided on the inner surface of the upper part of the sheath tube 5, thereby fixing the restraint jig 16d to the upper part of the sheath tube 5.

[0091] As described above, the restraining jig 16d, fixed to the upper part of the sheath pipe 5 via the insertion tool 17b, and the string-like member 15b, supported by the restraining jig 16d, connect the closing frame 8 and the sheath pipe 5. Next, the string-like member 15b is pulled upward from above the precast block 2 to tension the string-like member 15b extending between the restraining jig 16d and the connecting part 18, thereby restraining the middle portion of the string-like member 15b with the restraining jig 16d. In other words, the closing frame 8 is suspended from the sheath pipe 5 by the restraining jig 16d, fixed to the upper part of the sheath pipe 5 via the insertion tool 17b and the engaging part 5a, and the string-like member 15b, supported by the restraining jig 16d.

[0092] Next, as illustrated in Figures 14 and 15, when raising the closing frame 8 from a predetermined height L1 relative to the support 50, the restraint of the string-like member 10b by the restraint jig 11d, which is the holding jig 11, is released, and the upper part of the string-like member 10b is pulled upward, thereby moving the string-like member 10b upward relative to the restraint jig 11d. Similarly, the restraint of the string-like member 15b by the restraint jig 16d, which is the connecting jig 16, is released, and the upper part of the string-like member 15b is pulled upward, thereby moving the string-like member 15b upward relative to the restraint jig 16d. Then, as illustrated in Figure 15, at the position where the upper surface of the closing frame 8 contacts the bottom surface of the precast block 2, the string-like member 10b is restrained by the restraint jig 11d, which is the holding jig 11, and the string-like member 15b is restrained by the restraint jig 16d, which is the connecting jig 16. By performing the above steps, the closing frame 8 seals the gap between the outer surface of the support 50 and the lower end of the through hole 3 in the precast block 2.

[0093] If the length of each string-like member 10b and 15b is pulled up during the process of raising the closing frame 8 becomes large, the load and distortion on the suspension position changing means 9, the suspension assisting means 14, and the closing frame 8 will increase. Therefore, it is preferable to pull up each string-like member 10b and 15b in a balanced manner by sequentially changing which string-like member 10b and 15b is being pulled up, so that the length of each string-like member 10b and 15b is pulled up to be approximately equal. When the closing frame 8 comes into contact with the bottom surface of the precast block 2, the string-like members 10b and 15b can no longer be pulled up, so it is possible to easily determine from above the precast block 2 whether or not the closing frame 8 is in contact with the bottom surface of the precast block 2, and the closing frame 8 can be pressed against the bottom surface of the precast block 2 with an appropriate amount of force.

[0094] After the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2 is sealed with the closing frame 8, the filling material 30 is filled between the outer surface of the support 50 and the inner surface of the through hole 3 from above the precast block 2, similar to the embodiments illustrated in Figures 10 and 11. After that, the filling material 30 is allowed to harden after curing for a predetermined period, thereby fixing the superstructure 1, which integrates the precast block 2 and the hardened filling material 30, to the top of the support 50. With this, the construction of the superstructure 1 is completed. The respective suspension position changing means 9 and suspension assisting means 14 become embedded in the filling material 30.

[0095] As in this embodiment, by using a string-like member 10b as the suspension member 10 constituting the suspension position changing means 9, and using a restraining jig 11d equipped with an engaging portion 12 as the holding jig 11, the suspension position changing means 9 can be constructed simply. Furthermore, by using a string-like member 15b as the connecting member 15 constituting the suspension assisting means 14, and using a restraining jig 16d equipped with an engaging portion 17 as the connecting jig 16, the suspension assisting means 14 can be constructed simply.

[0096] In the process of temporarily positioning the closure frame 8 at a predetermined height L1, the closure frame 8 can be suspended at the predetermined height L1 simply by engaging the engaging portion 12 provided on the suspension position changing means 9 with the upper part of the support 50 and fixing it in place, using the engaging portion 12, the restraining jig 11d, and the string-like member 10b. Therefore, the process of temporarily positioning the closure frame 8 at a predetermined height L1 can be performed easily and efficiently. 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 process of bringing the upper surface of the closure frame 8 into contact with the bottom surface of the precast block 2 can also be performed easily and efficiently.

[0097] As in this embodiment, when using a restraining jig 11d (16d) having a self-locking function (automatic tightening function), even if the worker releases their hand from the string-like member 10b (15b) when raising the closure frame 8 from a predetermined height L1, the string-like member 10b (15b) will be automatically restrained by the restraining jig 11d (16d). Therefore, the risk of the closure frame 8 falling unintentionally can be reduced, which is advantageous for performing the operation of raising the closure frame 8 more safely.

[0098] The closure mechanism of the present invention can also be configured as illustrated in Figures 16 to 19. As illustrated in Figure 16, the configuration of the precast block 2, closure frame 8, suspension position changing means 9, and engaging part 12 used in this embodiment is the same as in the previous embodiment illustrated in Figures 1 to 11. This embodiment differs from the previous embodiment illustrated in Figures 1 to 11 in that the suspension assisting means 14 is not used. Other differences are described below.

[0099] As illustrated in Figure 16, in this embodiment, multiple suspension position changing means 9 are arranged in a plan view so as to surround the outside of the insertion hole of the closing frame 8. Then, during work in the construction water area where the superstructure 1 is to be constructed, the closing frame 8 is fitted onto the support 50 in a state that allows it to move vertically, the lower ends of the multiple suspension position changing means 9 are connected to the upper part of the closing frame 8, and the engaging parts 12 provided on each suspension position changing means 9 are engaged with the upper part of the support 50, thereby temporarily positioning the closing frame 8 at a predetermined height L1 of the support 50 using the multiple suspension position changing means 9.

[0100] More specifically, in this embodiment, when temporarily positioning the closing frame 8 at a predetermined height L1, the engaging parts 12 (hooks 12a) provided on the multiple suspension position changing means 9 are engaged with the upper part of the support 50. Then, the holding jig 11 (insertion fitting 11a, nut 11b, washer 11c) fixed to the upper part of the support 50 via the engaging parts 12, and the suspension member 10 supported by the holding jig 11, suspend each of the divided members constituting the closing frame 8 at the predetermined height L1.

[0101] Next, as illustrated in Figure 17, the precast block 2, which has through holes 3 that penetrate 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 holes 3. In this state, the closing frame 8 is suspended from the support 50 by the holding jig 11 (insertion fitting 11a) fixed to the upper part of the support 50 via the engaging part 12, and the suspension member 10 supported by the holding jig 11 (insertion fitting 11a, nut 11b).

[0102] Subsequently, as illustrated in Figure 18, in this embodiment, the engaging portion 12 provided on each suspension position changing means 9 is removed from the upper part of the support 50, and the engaging portion 12 provided on each suspension position changing means 9 is engaged with the engaged portion 3b provided on the inner circumference 3a of the through hole 3 of the precast block 2. More specifically, in this embodiment, the engaging portion 12 (hook 12a) provided on the holding jig 11 located on the upper part of each suspension member 10 (rod-shaped member 10a) is removed from the upper part of the support 50, and the removed engaging portion 12 is engaged with the upper end of the sheath tube 5, which is the engaged portion 3b. As a result, the closing frame 8 is suspended from the precast block 2 by the holding jig 11 (insertion fitting 11a) fixed to the engaged portion 3b (upper part of the sheath tube 5) via the engaging portion 12, and the suspension member 10 supported by the holding jig 11 (insertion fitting 11a, nut 11b). The process of detaching the engaging portion 12 provided on the suspension position changing means 9 from the upper part of the support 50 and engaging it with the engaged portion 3b should not be performed simultaneously at multiple suspension position changing means 9 locations, but rather one location at a time.

[0103] In this embodiment, the nut 11b is rotated relative to the rod-shaped member 10a to move the nut 11b upward relative to the rod-shaped member 10a, thereby moving the insertion fitting 11a, washer 11c, and engaging part 12 (hook 12a) upward, and thus the engaging part 12 and holding jig 11 are removed from the upper part of the support 50. Next, the removed engaging part 12 is engaged with the upper part of the sheath tube 5, so that the insertion fitting 11a and washer 11c are positioned near the upper part of the sheath tube 5 with the rod-shaped member 10a inserted through it. Then, the nut 11b is rotated relative to the rod-shaped member 10a to move the nut 11b downward relative to the rod-shaped member 10a, so that the nut 11b is positioned on top of the insertion fitting 11a.

[0104] Next, as illustrated in Figure 19, by operating each of the suspension position changing means 9 from above the precast block 2, the closing frame 8 is raised from a predetermined height L1 relative to the support 50, so that the upper surface of the closing frame 8 comes into contact with the bottom surface of the precast block 2 (block body 4), and the closing frame 8 closes the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2. In other words, in this embodiment, the closing frame 8 is fixed to the precast block 2 by multiple suspension position changing means 9.

[0105] Subsequently, similar to the embodiment illustrated in Figure 10, the filling material 30 is filled between the outer surface of the support 50 and the inner surface of the through hole 3 and solidified, thereby fixing the superstructure 1, which integrates the precast block 2 and the solidified filling material 30, to the top of the support 50.

[0106] As in this embodiment, even when the precast block 2 is temporarily fixed to the support 50 and then the engaging portion 12 provided on each suspension position changing means 9 is engaged with the engaged portion 3b provided on the inner circumference 3a of the through hole 3 of the precast block 2, the same effects as those of the previous embodiment illustrated in Figures 1 to 11 can be achieved. With this configuration, the gap between the outer surface of the support 50 and the lower end of the through hole 3 of the precast block 2 is closed by the closing frame 8, and the closing frame 8 is fixed to the precast block 2 by the multiple suspension position changing means 9. This is more advantageous in suppressing the separation between the upper surface of the closing frame 8 and the bottom surface of the precast block 2.

[0107] On the other hand, as illustrated in the embodiments shown in Figures 1 to 11, if the precast block 2 is temporarily fixed to the support 50 and the engaging portion 12 provided on each suspension position changing means 9 is left engaged with the upper part of the support 50, there is no need to remove the engaging portion 12 from the upper part of the support 50 and engage it with the engaged portion 3b, which is advantageous in reducing the number of man-hours required to construct the superstructure 1.

[0108] In this embodiment, the upper end of the sheath pipe 5 provided in the precast block 2 is shown as the engaged portion 3b. However, for example, the precast block 2 may not have a sheath pipe 5, and a groove or fitting may be provided on the concrete surface of the inner circumference 3a of the through hole 3 of the precast block 2 as the engaged portion 3b to which the engaging portion 12 provided in the suspension position changing means 9 can be engaged. For example, the precast block 2 may have a sheath pipe 5, and a groove or fitting may be provided on the inner surface of the sheath pipe 5 as the engaged portion 3b.

[0109] In the embodiment described above, an example was given in which the support 50 is positioned higher than the water surface level WL while the closure frame 8 is temporarily placed at a predetermined height L1 of the support 50. However, for example, the predetermined height L1 can also be set to the water surface level WL. In that case, a buoyancy body can be provided at the bottom of the closure frame 8, and the closure frame 8 can be temporarily placed floating on the water by the buoyancy body. The aforementioned buoyancy body can be made of, for example, a hollow box, or a foam with many air bubbles inside, such as polystyrene foam.

[0110] The suspension position changing means 9 and suspension assisting means 14 of the embodiment illustrated in Figures 1 to 11, the suspension position changing means 9 and suspension assisting means 14 of the embodiment illustrated in Figures 12 to 15, and the suspension 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 arbitrarily as appropriate. For example, the suspension position changing means 9 of the embodiment illustrated in Figures 1 to 11 can be combined with the suspension assisting means 14 of the embodiment illustrated in Figures 12 to 15. For example, the suspension position changing means 9 of the embodiment illustrated in Figures 16 to 19 can be the suspension position changing means 9 of the embodiment illustrated in Figures 12 to 15. That is, in the embodiments illustrated in Figures 16 to 19, for example, an inserting tool 12b can be provided as an engaging part 12 on the holding jig 11 (restraining jig 11d), engaging devices 50a can be arranged at multiple locations on the outer peripheral surface of the upper part of the support 50, and engaging devices 5a can be arranged as engaging parts 3b at multiple locations on the inner surface of the upper part of the sheath tube 5. For example, the embodiments illustrated in Figures 1 to 11 and the embodiments illustrated in Figures 12 to 15 can be configured without providing the suspension assisting means 14.

[0111] In the embodiment illustrated in Figures 16 to 19, the precast block 2 is temporarily fixed to the support body 50, and then the engaging portions 12 provided on all the suspension position changing means 9 arranged on the closing frame 8 are moved from the upper part of the support body 50 to the engaged portion 3b. However, in this closing mechanism, for example, the engaging portions 12 provided on some of the suspension position changing means 9 arranged on the closing frame 8 can be moved from the upper part of the support body 50 to the engaged portion 3b, while the engaging portions 12 provided on the other suspension position changing means 9 remain engaged with the upper part of the support body 50. That is, the closing frame 8 and the support body 50 can be connected by some of the suspension position changing means 9 arranged on the closing frame 8, and the closing frame 8 and the precast block 2 can be connected by the other suspension position changing means 9.

[0112] The suspension position changing means 9 is not limited to the configuration exemplified above, and can be configured in various ways as long as it has the function of the suspension position changing means 9 as described above. The suspension assisting means 14 is also not limited to the configuration exemplified above, and can be configured in various ways as long as it has the function of the suspension assisting means 14 as described above. Furthermore, the structure of the engaging portion 12 provided on the suspension position changing means 9, the engaging portion 17 provided on the suspension assisting means 14, the engaged device 50a provided on the support 50, and the engaged portion 3b (engaged device 5a) provided on the precast block 2 is not limited to the embodiment described above, and can be configured in various ways.

[0113] A major advantage of this construction method using the closure mechanism is that it minimizes or eliminates the need to work under the precast blocks 2 installed on the support 50. However, it does not completely eliminate the need to work under the precast blocks 2. For example, if it is necessary to visually confirm that there is no gap between the bottom surface of the precast block 2 and the top surface of the closure frame 8, work can be performed under the precast blocks 2 as needed.

[0114] The shape and size of the superstructure 1 (precast block 2) are not limited to the embodiment exemplified above, and various other configurations are possible. In this embodiment, the case of constructing a superstructure 1 fixed to a single support 50 was exemplified, but for example, it is also possible to construct a superstructure 1 that extends across multiple support 50 by manufacturing a precast block 2 having multiple through holes 3 and loosely inserting separate support 50 into each through hole 3. Furthermore, for example, it is possible to construct a superstructure 1 that is L-shaped, polygonal, or circular in shape when viewed from above. In the embodiment exemplified above, the case where the support 50 is a pile was exemplified, but the same construction method can be used to achieve the same effect even when the support 50 is a sheet pile. [Explanation of symbols]

[0115] 1 Superstructure 2 Precast Blocks 3 Through hole 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. Means for changing the suspension position 10 Hanging members 10a Rod-shaped member 10b String-like member 11. Holding fixture 11a Insertion fitting 11b Nut 11c washer 11d Restraint fixture 12 Engaging part 12a Hook 12b Insert 13 Connecting part 14 Lifting aids 15 Connecting Members 15a Rod-shaped member 15b String-like member 16. Connecting jig 16a Insertion fitting 16b Nut 16c washer 16d Restraint fixture 17 Engaging part 17a Hook 17b Insert 18 Connection part 20 bands 21 Adhesive Tape 30 Filling material 40 partition plates 50 Support 50a Engaged tool 60 Impact Driver 61 Fittings WB Underwater ground WL water surface position L1 (Predetermined height for temporarily positioning the closing frame) L2 (Planned height for installing precast blocks)

Claims

1. A sealing mechanism used to seal the gap between the support and the through-hole when temporarily fixing the superstructure to the support by filling the space between the outer surface of the support and the inner surface of the through-hole with a filling material, after loosely inserting the through-hole of the superstructure into the support and fixing it in place, A closing frame body is disposed on the outer surface of the support, A means for changing the suspension position connected to the aforementioned closing frame, The suspension position changing means is provided with an engaging portion that engages with the upper part of the support, The closure mechanism is characterized by comprising a suspension member extending vertically with the engaging portion engaged with the support, and a holding jig provided midway along the suspension member to hold the suspension member in a state where it can move relative to the suspension member in the vertical direction.

2. The suspension member is a rod-shaped member provided with screw threads. The closing mechanism according to claim 1, wherein the retaining jig comprises an insertion fitting provided in the engagement portion through which the rod-shaped member is inserted, and a nut disposed in the insertion fitting and screwed into the screw groove of the rod-shaped member.

3. The suspension member is a string-like member, The closure mechanism according to claim 1, wherein the retaining jig is provided on the engaging portion and has a restraining jig that can be switched between a state in which the string-like member is restrained and a state in which it is not restrained.

4. It has a suspension assisting means connected to the aforementioned closing frame, The closure mechanism according to claim 1, wherein the suspension assisting means comprises an engaging portion that engages with a through hole in the superstructure while the superstructure is temporarily fixed to the support, a connecting member connected to the closure frame, and a connecting jig that holds the connecting member in a state where it can move relative to the support in the vertical direction.

5. The closing mechanism according to claim 1, wherein the closing frame is composed of a plurality of divided members.

Images