Closing mechanism and superstructure construction method

Abstract

To provide a superstructure construction method which can efficiently construct a superstructure on the water, without performing work below a precast block installed on a support erected on a water bottom ground.SOLUTION: A closing frame body 8 is externally fit to a support 40 so as to be removable in a vertical direction, and is temporarily arranged. The support 40 is freely inserted into a through hole 3 of a precast block 2, and the bottom surface of the precast block 2 is brought into contact with the upper surface of the closing frame body 8, the precast block 2 and the closing frame body 8 are moved downward up to a predetermined installation height, and a state in which the upper surface of the closing frame body 8 is brought into contact with the bottom surface of the precast block 2 is maintained by contact maintenance means 9. A filling material 20 is filled between the outer peripheral surface of the support 40 and the inner peripheral surface of the through hole 3, and a superstructure 1 in which the precast block 2 and the solidified filler 20 are integrated with each other is fixed to the upper part of the support 40.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

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

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

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

[0005] The object of the present invention is to provide a closing mechanism and a method for constructing a superstructure that can efficiently construct an above-water superstructure without performing work below precast blocks installed on supports such as piles or sheet piles erected on the bottom ground. [Means for solving the problem]

[0006] The closing mechanism of the present invention for achieving the above-mentioned object is a closing mechanism that closes the gap between the outer surface of the support and the insertion hole when a support erected on the bottom ground is inserted into the insertion hole of a precast block, which is a component of the superstructure, and a filler material is filled between the outer surface of the support and the inner surface of the insertion hole and solidified, and is characterized by having a closing frame body that is fitted onto the support and can move in the vertical direction, and has a surface facing the gap, and when the precast block abuts against the closing frame body from above and the closing member is pressed down, generates an upward force that resists the pressure, and uses the upward force to keep the closing frame body in abutment against the precast block. The method for constructing a superstructure of the present invention comprises the steps of inserting a support member erected on the bottom ground into an insertion hole of a precast block, which is a component of the superstructure; blocking the gap between the outer surface of the support member and the insertion hole using a blocking mechanism; and filling the gap between the outer surface of the support member and the inner surface of the insertion hole with a filler material and solidifying it.The blocking mechanism is characterized by comprising a blocking frame body that is fitted onto the support member and is movable in the vertical direction, and has a surface facing the gap, and a contact maintenance means that generates an upward force that resists the pressure when the precast block abuts against the blocking frame body from above and pushes down the blocking member, and uses the upward force to maintain the blocking frame body in contact with the precast block. [Effects of the Invention]

[0007] According to the present invention, a blocking frame is temporarily positioned on the support body so that it can move vertically. A precast block having a through hole is moved downward from above the support body, loosely inserting the support body into the through hole so that the bottom surface of the precast block abuts against the upper surface of the blocking frame body. From this state, the precast block and the blocking frame body are moved downward to a predetermined installation height, and the abutment maintaining means maintains the upper surface of the blocking frame abutting against the bottom surface of the precast block. This allows the blocking frame to close the gap between the outer surface of the support body and the lower end of the through hole in the precast block without requiring work below the precast block installed on the support body. Then, fill material is filled between the outer surface of the support body and the inner surface of the through hole in the precast block and solidified, allowing efficient construction of a superstructure above water without requiring work below the precast block installed on the support body. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram illustrating a side view of a superstructure constructed on top of a support using the method for constructing a superstructure on water of the present invention. [Figure 2] This is an explanatory diagram showing a cross-sectional view of a closure frame body provided with an elastic member as a means for maintaining contact when temporarily placed on the support body, and a precast block. [Figure 3] FIG. 3 is a view taken along the arrow A in FIG. 2. [Figure 4] 4 is an explanatory diagram illustrating a cross-sectional view of the state in which the precast block is installed on the support from the state shown in FIGS. 2 and 3. FIG. [Figure 5] FIG. 5 is a view taken along arrow B in FIG. 4. [Figure 6] 6 is an explanatory diagram illustrating a cross-sectional view of the state in which a fill material has been filled and solidified between the outer peripheral surface of the support body and the inner peripheral surface of the through hole of the precast block from the state of FIGS. 4 and 5. FIG. [Figure 7] FIG. 7 is a view taken along arrow C in FIG. 6. [Figure 8] FIG. 10 is an explanatory diagram illustrating, in cross section, a state in which a closure frame body provided with a buoyant body as a contact maintaining means is temporarily placed on a support body while floating on the water. [Figure 9] 9 is an explanatory diagram illustrating a cross-sectional view of the state in which the precast block is installed on the support from the state shown in FIG. 8. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] The following describes the closing mechanism and superstructure construction method of the present invention based on the embodiment shown in the drawings.

[0010] As shown in Fig. 1, the present invention is a method for constructing an overwater superstructure 1 such as a pier or revetment that is fixed to the top of supports 40 such as piles or sheet piles driven into the waterbed WB. Examples of supports 40 include piles such as steel pipe piles or concrete piles, and sheet piles such as steel pipe sheet piles. In the embodiment illustrated in Figs. 1 to 7 described below, the supports 40 are piles.

[0011] 1 to 7 illustrate the case where a superstructure 1 is constructed that is fixed to the top of one support 40, but the present invention also allows for the construction of a superstructure 1 that is fixed to the top of two or more supports 40. The superstructure 1 above water in the present invention is not limited to a superstructure 1 that is always above water level, but also includes a superstructure 1 that is temporarily partially submerged in water due to tidal fluctuations, etc.

[0012] As illustrated in Figures 2 and 3, in the present invention, a superstructure 1 is constructed using precast blocks 2, a closure frame 8, and abutment maintaining means 9, which have been fabricated in advance on land or on a ship. The precast blocks 2 are formed, for example, from precast concrete, prestressed concrete, resin, or the like. The precast blocks 2 may be, for example, a reinforced concrete (steel-reinforced concrete) structure in which reinforcing bars (or steel frames) are embedded in the precast concrete or prestressed concrete, or a structure in which reinforcing bars, etc., are not embedded in the precast concrete or prestressed concrete.

[0013] The precast block 2 has a through hole 3 that passes through vertically, into which the support body 40 can be loosely inserted. In this embodiment, the through hole 3 is formed in one location in the center of the precast block 2. The precast block 2 of this embodiment is configured to include a block body 4 made of precast concrete and having the through hole 3 formed therein, a sheath pipe 5 that extends vertically and is fitted into the through hole 3, a beam member 6 that protrudes inside the through hole 3 in a plan view, and a hanging hardware 7.

[0014] In this embodiment, the block body 4 has a rectangular parallelepiped outer shape, but the outer shape of the block body 4 is not limited to a rectangular parallelepiped shape and may have other shapes. In this embodiment, a through hole 3 is formed in one location in the center of the block body 4.

[0015] The sheath pipe 5 can be optionally provided in the precast block 2, and a precast block 2 without the sheath pipe 5 can also be used. The sheath pipe 5 can be a resin tubular member formed from fiber reinforced plastic (FRP) or a metal tubular member such as a steel pipe. In this embodiment, the upper end of the sheath pipe 5 is located at a position lower than the upper end surface of the precast block 2. In other words, there is a portion above the through hole 3 of the precast block 2 where the sheath pipe 5 is not provided.

[0016] In the present invention, in the area where the sheath pipe 5 of the precast block 2 is provided, the inner peripheral surface of the sheath pipe 5 is the inner peripheral surface of the lower part of the through hole 3. In the area where the sheath pipe 5 of the precast block 2 is not provided, the concrete surface inside the through hole 3 is the inner peripheral surface of the through hole 3.

[0017] The inner dimensions of the through hole 3 (in this embodiment, the inner dimensions of the sheath tube 5) are set to dimensions that allow loose insertion of the support body 40. The inner dimensions of the through hole 3 are preferably set to dimensions that leave a gap (clearance) of, for example, 5 cm or more and 20 cm or less, more preferably 10 cm or more and 15 cm or less, between the inner circumferential surface of the through hole 3 and the outer circumferential surface of the support body 40 when the support body 40 is inserted into the through hole 3 with the center position of the through hole 3 and the center position of the support body 40 aligned in a plan view.

[0018] The beam members 6 are made of steel such as H-shaped steel or channel steel, or rod-shaped members made of resin. In this embodiment, H-shaped steel is used as the beam members 6. The beam members 6 extend horizontally, and in plan view, the beam members 6 protrude into the inside of the through hole 3 (sheath pipe 5). At least a portion of the beam members 6 extends to the outside of the through hole 3 in plan view. As illustrated in Figures 2 and 3, in this embodiment, the beam members 6 are arranged so as to cross each other in a plan view, and the beam members 6 span across the through hole 3.

[0019] As illustrated in FIG. 2, the beam members 6 are arranged, for example, above the sheath pipes 5 or on top of the sheath pipes 5. In this embodiment, grooves into which the respective beam members 6 are fitted are formed in the upper part of the sheath pipes 5, and the beam members 6 are fitted into the grooves. For example, the beam members 6 can also be placed on the sheath pipes 5. The portions of the beam members 6 located inside the through holes 3 are exposed, and the portions of the beam members 6 located outside the through holes 3 are embedded in the precast concrete that constitutes the block body 4. The upper ends of the beam members 6 are arranged at a position lower than the upper end surface of the precast block 2.

[0020] The upper part of the block body 4 is provided with a plurality of lifting fittings 7 that are used when lifting the precast blocks 2 with a crane or the like. In this embodiment, a lifting fitting 7 is provided at each of the four corners of the upper part of the block body 4. The lower part of each lifting fitting 7 is embedded in the precast concrete that makes up the block body 4, and the lifting fittings 7 are integrated into the block body 4. The lifting fittings 7 can be optionally provided on the precast blocks 2. If the precast blocks 2 are to be lifted using a method that does not use the lifting fittings 7, a precast block 2 without the lifting fittings 7 can also be used. Although not shown in this embodiment, if accessories such as mooring bollards are to be provided on the superstructure 1, the accessories such as mooring bollards can also be integrated into the precast blocks 2 (block body 4).

[0021] As illustrated in Figures 2 and 3, the closure frame 8 is temporarily positioned on the support body 40 before the precast block 2 is installed on the support body 40. The closure frame 8 is fitted onto the support body 40 in a state in which it can move up and down relative to the support body 40. In a plan view, the closure frame 8 extends outward from the outer peripheral surface of the support body 40. In a plan view, the closure frame 8 extends outward beyond the through hole 3 of the precast block 2. The closure frame 8 is made of a plate-like member made of, for example, metal, resin, or wood. In this embodiment, the closure frame 8 has a circular outer shape in a plan view, but the outer shape of the closure frame 8 in a plan view can also be other shapes, such as a polygonal shape.

[0022] In this embodiment, a flexible gap filling member 8a is provided on the inner circumferential side of the closure frame 8 in a ring shape in a plan view. The rear end of the gap filling member 8a is joined to the closure frame 8, and the tip end of the gap filling member 8a on the inner circumferential side abuts against the outer circumferential surface of the support body 40. The gap filling member 8a may be made of a member that has flexibility, conformability, and airtightness, such as a rubber plate-like member or sponge. This embodiment illustrates the case where a rubber plate-like member is used as the gap filling member 8a. The gap filling member 8a can be made of a single ring-shaped member, or it can be made of a combination of multiple divided members to form a ring shape.

[0023] In this embodiment, an intervening member 8b is further provided on the inner surface of the closure frame 8, which abuts against the outer surface of the support 40, to fill the gap between the outer surface of the support 40 and the inner surface of the closure frame 8. The intervening member 8b, which fills the gap between the outer surface of the support 40 and the inner surface of the closure frame 8, can also be provided on the outer surface of the support 40, for example. The intervening member 8b is made of an elastic material such as rubber. The intervening member 8b may be made of a highly elastic rubber material commonly used in packing. Either a solid or hollow member can be used, but a solid member is preferred. The outer diameter of the support 40 and the inner diameter of the intervening member 8b are preferably substantially the same. The width (radial thickness) of the intervening member 8b is preferably set to, for example, 5 mm to 15 mm, more preferably 8 mm to 12 mm. The intervening member 8b can also be made of a material, such as fluororesin, that reduces friction between the outer surface of the support 40 and the inner surface of the closure frame 8. As a method for reducing friction between the outer peripheral surface of the support body 40 and the inner surface of the closure frame 8, for example, a lubricant can be applied to the outer peripheral surface of the support body 40 or the inner surface of the closure frame 8. For example, wheels or bearings can be provided on the inner surface of the closure frame 8 as a member for reducing friction between the outer peripheral surface of the support body 40 and the inner surface of the closure frame 8. Note that the intervening member 8b can also be configured from a member that does not have the effect of reducing friction between the outer peripheral surface of the support body 40 and the inner surface of the closure frame 8.

[0024] The closure frame 8 of this embodiment is composed of multiple divided members that are radially divided in a plan view. The closure frame 8 of this embodiment is composed of two divided members. One side of each of the two divided members is connected by a hinge portion 8c, and a connecting portion 8d is provided on the other side of each of the two divided members. Each divided member is fitted onto the support body 40, and the connecting portions 8d of a pair of divided members are connected to each other, for example, by bolting, so that the closure frame 8 is fitted onto the support body 40. The closure frame 8 can also be composed of, for example, three or more divided members. The closure frame 8 can also be composed of, for example, a single member that is annular in a plan view. In this case, the closure frame 8 is moved downward from above the support body 40 to be fitted onto it. Constructing the closure frame 8 from a single member that is annular in a plan view has the advantage of allowing the closure frame 8 to be constructed very simply.

[0025] 4 and 5, the contact maintaining means 9 is a means for maintaining the upper surface of the closure frame 8 in contact with the bottom surface of the precast block 2 when the closure frame 8 closes the gap between the outer peripheral surface of the support 40 and the lower end of the through-hole 3 in the precast block 2. In this embodiment, an elastic member 9a is used as the contact maintaining means 9. The elastic member 9a may be, for example, a rubber string-like member, a band-like member, or a spring member.

[0026] As illustrated in FIGS. 2 and 3 , in this embodiment, the fixing portion 11 is fixed to the upper portion of the support body 40, which is positioned above the closure frame 8, and the fixing portion 11 and the upper end of the closure frame 8 are connected at multiple locations by elastic members 9a. A plurality of elastic members 9a are arranged so as to surround the insertion holes inside the closure frame 8 in a plan view. In this embodiment, the fixing portion 11, which is annular in a plan view, is fixed in a state in which it is fitted onto the support body 40. More specifically, the fixing portion 11 in this embodiment is composed of two separate members. One side of each of the two separate members is connected by a hinge portion 11a, and the other side of each of the two separate members is provided with a connecting portion 11b. Each separate member is fitted onto the support body 40, and the connecting portions 11b of the separate members are connected to each other, for example, by bolting, so that the fixing portion 11 is fitted onto the support body 40 and fixed thereto.

[0027] The fixing portion 11 can also be formed, for example, from a single member that is annular in plan view. In that case, the fixing portion 11 is moved downward from above the support 40 and fitted onto the outside. Forming the fixing portion 11 from a single member that is annular in plan view has the advantage of allowing the fixing portion 11 to be formed very simply. The fixing portion 11 can also be fixed to the support 40, for example, by other methods. Also, in this embodiment, the upper ends of the multiple elastic members 9a are fixed to a single fixing portion 11, but, for example, a separate fixing portion 11 can be provided on the support 40 for each elastic member 9a. For example, a configuration can be adopted in which the upper ends of the respective elastic members 9a are directly joined to the support 40 without providing the fixing portion 11.

[0028] As illustrated in Figures 2 and 3, in this embodiment, before the precast block 2 is installed on the support 40, the closure frame 8 is temporarily positioned on the support 40 by connecting the closure frame 8 to a fixing portion 11 provided on the upper portion of the support 40, which is located above the closure frame 8, with multiple elastic members 9a. In other words, the closure frame 8, which can move up and down relative to the support 40, is suspended by multiple elastic members 9a. The number and arrangement of the elastic members 9a are not limited to this embodiment, and various other configurations are possible, as long as the closure frame 8 can be suspended by the elastic members 9a. Note that the elastic members 9a do not necessarily need to be formed entirely longitudinally from an elastic material; at least a portion of the elastic members 9a in the longitudinal direction may be formed from an elastic material. In other words, a portion of the elastic members 9a may be formed from a non-elastic material.

[0029] In this embodiment, a plurality of hanging members 10 are further provided on the closure frame 8. The hanging members 10 are, for example, string-like or cable-like members made of metal or resin. The resin hanging members 10 may be formed, for example, from fiber-reinforced plastic (FRP). In this embodiment, a plurality of hanging members 10 are arranged so as to surround the insertion holes inside the closure frame 8 in a plan view. A plurality of lower connection portions 8e are provided at the upper end of the closure frame 8, and the lower ends of the hanging members 10 are connected to each of the lower connection portions 8e. As illustrated in FIG. 3, in this embodiment, a plurality of upper connection portions 6a are provided on the beam member 6, to which the upper portions of the hanging members 10 can be connected.

[0030] The specific work procedures for the method of constructing the superstructure 1 of the present invention will be described below.

[0031] As illustrated in Figures 2 and 3, the precast blocks 2 and closure frame body 8 having the above-described configuration are fabricated in advance on land or on a ship to match the size of the support body 40 that will construct the superstructure 1. The precast blocks 2 and closure frame body 8 are then transported to the construction waters where the support body 40 is erected. In this embodiment, the fixing parts 11 having the above-described configuration are also fabricated in advance on land or on a ship to match the size of the support body 40, and then transported to the construction waters. In this embodiment, the closure frame body 8 and the fixing parts 11 are connected in advance by a plurality of elastic members 9a, and the lower ends of the hanging members 10 are connected to the plurality of lower connection parts 8e provided at the upper end of the closure frame body 8, respectively, before the entire assembly is transported to the construction waters.

[0032] During work in the construction water area where the superstructure 1 is to be constructed, a partition plate 30 is installed at a predetermined depth from the upper end of the support 40 to separate the interior of the support 40 into upper and lower sections. The outer dimensions of the partition plate 30 are set to be approximately the same as the inner dimensions of the support 40. There are no particular restrictions on the method for installing the partition plate 30 inside the support 40, but for example, the partition plate 30 is fixed inside the support 40 by supporting it with a hanging member such as a wire suspended from the upper end of the support 40.

[0033] As illustrated in FIGS. 2 and 3 , the closure frame 8 is temporarily positioned by fitting it onto the support 40 in a manner that allows it to move up and down. In this embodiment, each of the divided members constituting the closure frame 8 is fitted onto the support 40, and the connecting portions 8d provided on each divided member are connected to each other, thereby fitting the closure frame 8 onto the support 40. In this embodiment, a gap filling member 8a is provided in advance on the inner periphery of the closure frame 8, and the gap filling member 8a is fitted onto the support 40 together with the closure frame 8. The inner periphery of the gap filling member 8a is abutted against the outer periphery of the support 40, so that no gap is formed between the outer periphery of the support 40 and the tip of the gap filling member 8a. As illustrated in FIG. 2 , the tip of the gap filling member 8a is pressed against the outer periphery of the support 40, and the tip of the gap filling member 8a is curved.

[0034] Next, the fixing part 11 is fixed to the upper part of the support body 40, which is positioned above the closure frame body 8. In this embodiment, each divided member constituting the fixing part 11 is fitted onto the support body 40, and the connecting parts 11b provided on each divided member are connected to each other, thereby fitting and fixing the fixing part 11 onto the support body 40. Then, the closure frame body 8, which is movable up and down relative to the support body 40, is suspended by multiple elastic members 9a, thereby temporarily positioning the closure frame body 8 relative to the support body 40. In this embodiment, the closure frame body 8 is temporarily positioned above the water surface position WL. The upper ends of each hanging member 10 are hooked onto the upper part of the support body 40.

[0035] Next, wire rope hoists suspended from a crane are connected to each of the hoisting fittings 7 on the precast block 2, and the precast block 2 is lifted above the support body 40 by the crane. Then, with the through holes 3 in the precast block 2 and the support bodies 40 aligned, the precast block 2 is moved downward from above the support bodies 40, and the support bodies 40 are loosely inserted into the through holes 3 of the precast block 2, so that the bottom surface of the precast block 2 abuts against the upper surface of the closure frame body 8.

[0036] 4 and 5, the precast block 2 and the closure frame 8 are then moved downward from the aforementioned state to a predetermined installation height, and the contact maintaining means 9 maintains the upper surface of the closure frame 8 in contact with the bottom surface of the precast block 2. In this embodiment, the beam member 6 protruding into the inside of the through hole 3 is placed on the upper end of the support 40, thereby positioning the precast block 2 at the predetermined installation height and supporting the precast block 2 on the upper side of the support 40. The closure frame 8 then closes the gap between the outer peripheral surface of the support 40 and the lower end of the through hole 3 in the precast block 2. Once the precast block 2 is supported on the upper side of the support 40, a worker can stand on the precast block 2 and perform work.

[0037] More specifically, in this embodiment, when the bottom surface of the precast block 2 is placed in contact with the upper surface of the closure frame 8 and the precast block 2 and the closure frame 8 are then moved downward from that state to a predetermined installation height, the elastic members 9a that make up the contact maintaining means 9 are extended. Then, due to the elastic force of the extended elastic members 9a attempting to contract, an upward force F (biasing force) acts on the closure frame 8, maintaining the state in which the upper surface of the closure frame 8 is in contact with the bottom surface of the precast block 2. Furthermore, when the precast block 2 and the closure frame 8 are moved downward to a predetermined installation height, the tip of the gap filling member 8a is maintained in contact with the outer peripheral surface of the support body 40.

[0038] Next, the closure frame body 8 and the precast block 2 are connected with the hanging members 10, and the closure frame body 8 is supported (fixed) by the hanging members 10 in a taut state (tensioned state). In this embodiment, the upper ends of the hanging members 10 hooked onto the upper ends of the supports 40 from above the precast block 2 are pulled up to the upper connection parts 6a provided on the beam members 6, and the upper ends of the taut hanging members 10 are fixed to the upper connection parts 6a.

[0039] 6 and 7, with the gap between the outer peripheral surface of the support body 40 and the lower end of the through hole 3 in the precast block 2 blocked by the blocking frame 8 (including the gap filling member 8a), filler material 20 is poured into the inside of the through hole 3 in the precast block 2. Then, filler material 20 is filled into the inside of the support body 40 above the partition plate 30, the gap between the outer peripheral surface of the support body 40 above the blocking frame 8 and the inner peripheral surface of the through hole 3, and the upper part of the through hole 3 above the support body 40.

[0040] Filling the through-hole 3 with the fill material 20 in one pour is advantageous for reducing the number of steps. The fill material 20 can also be poured in multiple pours, for example. Figure 6 illustrates an example in which the fill material 20 is poured in two pours. In this case, in the first pour, a first fill material 20a is poured between the outer circumferential surface of the support 40 and the inner circumferential surface of the through-hole 3 onto the closure frame 8 to a thickness of approximately 5 cm to 20 cm. The first fill material 20a is then solidified, forming a thin bottom plate on the closure frame 8. The remaining fill material 20 is then poured and solidified to fill the through-hole 3. The elastic member 9a and the hanging member 10 are buried in the fill material 20. In Figures 6 and 7, the area filled with the fill material 20 is indicated by diagonal lines.

[0041] After that, after a predetermined curing period has passed and the fill material 20 has hardened, the superstructure 1, in which the precast blocks 2 and the hardened fill material 20 are integrated, is fixed to the top of the support 40. This completes the construction work of the superstructure 1.

[0042] In this way, in the present invention, the blocking frame 8 is temporarily positioned by fitting it onto the support 40 in a manner that allows it to move up and down, and the precast block 2 having the through-hole 3 is moved downward from above the support 40, loosely inserting the support 40 into the through-hole 3 so that the bottom surface of the precast block 2 abuts against the upper surface of the blocking frame 8. From this state, the precast block 2 and the blocking frame 8 are moved downward to a predetermined installation height, and the abutment maintaining means 9 maintains the upper surface of the blocking frame 8 abutting against the bottom surface of the precast block 2. This allows the blocking frame 8 to close the gap between the outer surface of the support 40 and the lower end of the through-hole 3 in the precast block 2 without requiring any work below the precast block 2 installed on the support 40. Thereafter, the fill material 20 is filled between the outer surface of the support 40 and the inner surface of the through-hole 3 in the precast block 2 and solidified, allowing the superstructure 1 to be efficiently constructed above water without requiring any work below the precast block 2 installed on the support 40.

[0043] As in this embodiment, an elastic member 9a is used as the contact maintaining means 9, and when the blocking frame body 8 is temporarily placed on the support body 40, the upper part of the support body 40, which is located above the blocking frame body 8, is connected to the blocking frame body 8 by the elastic member 9a, thereby allowing the contact maintaining means 9 to be configured simply. When the precast block 2 and the blocking frame body 8 are moved downward to a predetermined installation height and an upward force F is applied to the blocking frame body 8 by the elastic force of the extended elastic member 9a, the upper surface of the blocking frame body 8 can be pressed against the bottom surface of the precast block 2, which is advantageous for preventing the upper surface of the blocking frame body 8 from separating from the bottom surface of the precast block 2.

[0044] Furthermore, as in this embodiment, by providing a fixing part 11 connected to the upper end of the elastic member 9a and configuring the fixing part 11 to be fixed to the upper part of the support body 40 located above the closure frame body 8 when temporarily positioning the closure frame body 8 relative to the support body 40, the work of connecting the upper part of the support body 40 and the closure frame body 8 with the elastic member 9a can be carried out very efficiently. Note that, without providing the fixing part 11, it is also possible to directly join the upper end of the elastic member 9a to the upper part of the support body 40, for example, by bolting, adhesive, welding, or the like.

[0045] As in this embodiment, after the precast block 2 and the closure frame 8 are moved downward to a predetermined installation height, the closure frame 8 and the precast block 2 are connected with the hanging members 10, and the closure frame 8 is supported by the tensioned hanging members 10. This allows the load on the closure frame 8 when filling it with fill material 20 to be supported not only by the contact maintaining means 9 but also by the hanging members 10. Therefore, providing the hanging members 10 is more effective in preventing the upper surface of the closure frame 8 from separating from the bottom surface of the precast block 2 during filling with fill material 20, resulting in leakage of the fill material 20. As in this embodiment, providing the beam member 6 with an upper connecting portion 6a to which the upper end of the hanging member 10 can be connected allows the work of connecting the closure frame 8 and the precast block 2 with the hanging members 10 to be performed efficiently. It should be noted that, without providing the upper connecting portion 6a, the upper end of the hanging member 10 can also be directly joined to the beam member 6, the sheath pipe 5, the inner surface of the through hole 3, or the like by bolting, adhesive, welding, or the like.

[0046] In this embodiment, the case where the closure frame 8 and the precast block 2 are connected with the hanging members 10 is illustrated. However, for example, after the precast block 2 and the closure frame 8 are moved downward to a predetermined installation height, the closure frame 8 and the upper part of the support 40 can be connected with the hanging members 10, and the closure frame 8 can be supported by the tensioned hanging members 10. In this case, too, the load applied to the closure frame 8 when filling it with the fill material 20 can be supported not only by the contact maintaining means 9 but also by the hanging members 10, which is more advantageous in preventing the upper surface of the closure frame 8 from separating from the bottom surface of the precast block 2 during filling, causing the fill material 20 to leak. Note that the case where the closure frame 8 and the upper part of the support 40 are connected with the hanging members 10 will be illustrated later in another embodiment.

[0047] As in this embodiment, if flexible gap filling members 8a are provided in a ring shape in plan view on the inner periphery of the blocking frame 8, and the tip of the inner periphery of the gap filling members 8a is kept in contact with the outer periphery of the support body 40 when the precast block 2 and the blocking frame 8 are moved downward to a predetermined installation height, this is more effective in preventing the fill material 20 from leaking out below the blocking frame 8 while it is being filled. Note that the gap filling members 8a can be provided arbitrarily as needed.

[0048] If an intervening member 8b is provided on at least one of the outer peripheral surface of the support 40 or the inner surface of the closure frame 8 to fill the gap between the outer peripheral surface of the support 40 and the inner surface of the closure frame 8, it is more effective in preventing the filler material 20 from leaking below the closure frame 8 during filling. If the intervening member 8b is made of an elastic material, even if the closure frame 8 (intervening member 8b) comes into contact with the support 40 when the precast block 2 and the closure frame 8 are moved downward to the predetermined installation height, the intervening member 8b will function as a buffer material, which is advantageous for protecting the outer peripheral surface of the support 40. Since a corrosion-resistant layer (corrosion-resistant cover) made of resin or the like may be provided on the outer peripheral surface of the support 40, this is very effective in preventing wear and damage to the corrosion-resistant layer. If the intervening member 8b is constructed of a material that reduces friction between the outer peripheral surface of the support 40 and the inner surface of the closure frame 8, the closure frame 8 can move smoothly relative to the support 40 when moving the precast block 2 and the closure frame 8 downward to a predetermined installation height. This is therefore advantageous for smooth construction. In this embodiment, the intervening member 8b is provided on the inner surface of the closure frame 8. However, for example, the intervening member 8b may be provided on the outer peripheral surface of the support 40, or on both the outer peripheral surface of the support 40 and the inner surface of the closure frame 8. A configuration that includes both the gap filling member 8a and the intervening member 8b is even more advantageous in preventing the fill material 20 from leaking below the closure frame 8 during filling. The intervening member 8b can be provided as needed.

[0049] As in this embodiment, when fabricating the precast block 2, if a beam member 6 is provided that protrudes inside the through hole 3 of the precast block 2, then by placing the beam member 6 on the upper end of the support 40, the precast block 2 can be easily and stably installed on top of the support 40. After the precast block 2 is installed on top of the multiple support bodies 40, workers can work by standing on top of the precast block 2, which is advantageous for improving construction efficiency.

[0050] The number and arrangement of the beam members 6 constituting the precast block 2 are not limited to the embodiment exemplified above, and for example, there can be one or three or more beam members 6 protruding inside the through hole 3. Also, for example, a configuration can be adopted in which the end of the beam member 6 is arranged inside the through hole 3 in a plan view, and the beam member 6 does not cross the through hole 3. Also, for example, a configuration can be adopted in which two beam members 6 are arranged side by side inside the through hole 3 in a plan view.

[0051] Pouring the fill material 20 in one go to fill the through-holes 3 is advantageous in reducing the number of steps required. On the other hand, when pouring the fill material 20, the weight of the fill material 20 is applied to the blocking frame 8. However, if the fill material 20 is poured in multiple steps and a thin bottom plate of approximately 5 cm to 20 cm is formed on the blocking frame 8 by the solidified fill material 20a in the first pour, this thin bottom plate functions together with the blocking frame 8 as a bottom plate to support the weight of the fill material 20 poured thereafter. Therefore, pouring the fill material 20 in multiple steps requires more steps than pouring all of the fill material 20 in one pour, but has the advantage of reducing the load on the blocking frame 8. Accordingly, the contact maintaining means 9 and the hanging member 10 that support the blocking frame 8 can be simplified.

[0052] As illustrated in Figures 8 and 9, in the present invention, the contact maintaining means 9 can also be configured, for example, by a buoyant body 9b provided on the closure frame body 8. In this embodiment, the configuration of the contact maintaining means 9 and the method of holding the closure frame body 8 in a suspended state by the hanging members 10 are different from those of the embodiment illustrated in Figures 1 to 7. The other configurations are the same as those of the embodiment illustrated in Figures 1 to 7.

[0053] As shown in Fig. 8, in this embodiment, a buoyant body 9b is provided on the closure frame 8 as the contact maintaining means 9. The buoyant body 9b is a member having a density lower than that of water (or seawater if the construction water area is an ocean area), and is made of, for example, resin or wood. The buoyant body 9b can be made of, for example, a hollow box, or a foam having many air bubbles inside, such as polystyrene foam.

[0054] As shown in Figure 8, in this embodiment, when the precast block 2 is temporarily placed on the support body 40, the closure frame body 8 provided with the buoyant body 9b is set to float on the water. As in the embodiment shown in Figures 1 to 7, the closure frame body 8 is fitted onto the support body 40 in a state in which it can move up and down. When the closure frame body 8 is temporarily placed on the support body 40, part of the buoyant body 9b is submerged, and the upper end surface of the closure frame body 8 is located above the water surface level WL. In this embodiment, a sponge with a closed-cell structure is used as the gap filling member 8a.

[0055] In this embodiment, a connection portion 12 for connecting the suspension member 10 to the support body 40 is provided on the upper portion of the support body 40, which is located above the closure frame 8. In this embodiment, the connection portion 12, which is annular in plan view, is fixed in a state in which it is fitted onto the support body 40. More specifically, the connection portion 12 in this embodiment is composed of two divided members. One side of each of the two divided members is connected by a hinge portion 12a, and the other side of each of the two divided members is provided with a connecting portion 12b. Each divided member is fitted onto the support body 40, and the connecting portions 12b of the pair of divided members are connected to each other, so that the connection portion 12 is fitted onto the support body 40 and fixed thereto. The connection portion 12 can also be composed of a single member that is annular in plan view, for example. In this case, the connection portion 12 is moved downward from above the support body 40 to be fitted onto it. Constructing the connection portion 12 from a single member that is annular in plan view has the advantage of allowing the connection portion 12 to be configured very simply.

[0056] As illustrated in Figure 8, in this embodiment, ring-shaped (annular) lower connection portions 8e are provided at multiple locations on the upper end of the closure frame 8. In this embodiment, a binding jig 13 is provided as a tool for adjusting the length of the hanging member 10 extending between the support body 40 (fixing portion 11) and the closure frame 8. The binding jig 13 has a self-locking function (automatic tightening function) that allows the hanging member 10 inserted into the binding jig 13 to move only to one side relative to the binding jig 13 and not to the other side.

[0057] 1 to 7, in this embodiment, too, the precast blocks 2 and the closure frame 8 are fabricated in advance on land, on a ship, or the like, to match the size of the support body 40 that will construct the superstructure 1. In this embodiment, the connecting portion 12 having the above-described configuration is also fabricated in advance on land, on a ship, or the like, to match the size of the support body 40. In this embodiment, the closure frame 8 and the connecting portion 12 are connected in advance by a plurality of hanging members 10, and the integrated body is then transported to the construction waters.

[0058] 8, one end of the hanging member 10 is fixed to the connection part 12, and the middle part of the hanging member 10 extending downward from the connection part 12 is inserted into the binding jig 13. Then, the middle part of the hanging member 10 extending downward from the binding jig 13 is inserted into the loop of the lower connection part 8e, and the middle part of the hanging member 10 extending upward from the lower connection part 8e is inserted into the binding jig 13. The other end of the hanging member 10 extending upward from the binding jig 13 is left in a free state.

[0059] During work in the construction waters where the superstructure 1 is to be constructed, the partition plate 30 is fixed inside the support body 40. In addition, the closure frame body 8 provided with the buoyancy body 9b is fitted onto the outside of the support body 40 in a state in which it can move up and down relative to the support body 40, and the closure frame body 8 provided with the buoyancy body 9b is temporarily positioned relative to the support body 40 in a state in which it is floating on the water.

[0060] Furthermore, the connection portion 12 is fixed to the upper part of the support 40, which is located above the closure frame 8. In this embodiment, each divided member constituting the connection portion 12 is fitted onto the support 40, and the connecting portions 12b provided on the pair of divided members are connected to each other, thereby fitting and fixing the connection portion 12 to the support 40. In this embodiment, the closure frame 8 can also be configured, for example, as a single member that is annular in plan view. In this case, the closure frame 8 is moved downward from above the support 40 to be fitted onto the support 40. When the closure frame 8 is temporarily placed on the support 40, a certain amount of slack is provided in the intermediate portion of the hanging member 10 located between the binding jig 13 and the lower connecting portion 8e. The other end of each hanging member 10, which is the free end, is hooked onto the upper part of the support 40.

[0061] Next, a crane is used to move the precast block 2 downward from above the support body 40, and the support body 40 is loosely inserted into the through hole 3 of the precast block 2 so that the bottom surface of the precast block 2 abuts against the upper surface of the blocking frame body 8.

[0062] Then, as illustrated in Figure 9, the precast block 2 and the closure frame 8 are moved downward from the above-described state to a predetermined installation height, and the contact maintaining means 9 maintains the state in which the top surface of the closure frame 8 is in contact with the bottom surface of the precast block 2. In this embodiment, when the bottom surface of the precast block 2 is in contact with the top surface of the closure frame 8 and the precast block 2 and the closure frame 8 are moved downward from that state to a predetermined installation height, an upward force F (biasing force) acts on the closure frame 8 due to the buoyancy of the portion of the buoyant body 9b that is submerged below the water surface. When the precast block 2 and the closure frame 8 are positioned at the predetermined installation height, the bottom surface of the precast block 2 and the closure frame 8 are positioned below the water surface level WL.

[0063] Next, the closure frame 8 and the upper part of the support 40 are connected with the hanging members 10, and the closure frame 8 is supported by the hanging members 10 in a taut (tensioned) state. As illustrated in FIG. 9 , in this embodiment, a worker from above the precast block 2 pulls up the other end of each hanging member 10 hooked to the upper part of the support 40, tautening the intermediate portion of the hanging member 10 located between the connection portion 12 and the lower connection portion 8e. In this embodiment, by providing the bundling jig 13, the worker can taut the intermediate portion of the hanging member 10 located between the connection portion 12 and the lower connection portion 8e simply by pulling up the other end of the hanging member 10. After that, even if the worker releases his / her hand from the other end of the hanging member 10, the self-locking function of the bundling jig 13 keeps the intermediate portion of the hanging member 10 located between the connection portion 12 and the lower connection portion 8e taut.

[0064] Before pouring the filler material 20, the other end of the hanging member 10 protruding outside the precast block 2 is cut off and collected. Alternatively, the other end of the hanging member 10 is placed inside the through hole 3 so that it does not protrude outside the precast block 2. Thereafter, as in the embodiment illustrated in FIGS. 1 to 7, the filler material 20 is poured into the through hole 3 of the precast block 2 while the gap between the outer peripheral surface of the support body 40 and the lower end of the through hole 3 of the precast block 2 is blocked by the blocking frame 8. After that, after a predetermined curing period has elapsed and the filler material 20 has hardened, the superstructure 1, in which the precast block 2 and the hardened filler material 20 are integrated, is fixed to the top of the support body 40.

[0065] As in this embodiment, by using a buoyant body 9b as the contact maintaining means 9 and temporarily placing the blocking frame body 8 on the support body 40, the blocking frame body 8 with the buoyant body 9b can be floated on the water, allowing the contact maintaining means 9 to be constructed very simply.

[0066] When connecting the closure frame 8 and the support 40 with the hanging member 10 as in this embodiment, providing a connection part 12 on the upper part of the support 40 to which one end of the hanging member 10 can be connected makes it possible to very efficiently connect the closure frame 8 and the support 40 with the hanging member 10. In addition, using a binding jig 13 makes it very easy to keep the hanging member 10 in a taut state.

[0067] Note that, for example, the hanging members 10 may be tensioned by other methods without using the binding jig 13. The connection portion 12 may also be fixed to the support body 40 by other methods, such as bonding with an adhesive or welding. Also, in this embodiment, one end of a plurality of hanging members 10 is fixed to one connection portion 12, but, for example, a separate connection portion 12 may be provided on the support body 40 for each hanging member 10. For example, one end of the hanging member 10 may be directly joined to the outer circumferential surface of the support body 40 by adhesive or welding without providing a connection portion 12.

[0068] While the above examples illustrate the use of an elastic member 9a and a buoyant body 9b as the contact maintaining means 9, the contact maintaining means 9 is not limited to the elastic member 9a or the buoyant body 9b, and various other configurations are possible as long as the contact maintaining means 9 is configured to maintain the upper surface of the closure frame 8 in contact with the bottom surface of the precast block 2 when the precast block 2 and the closure frame 8 are moved downward to the predetermined installation height. For example, the contact maintaining means 9 can be configured to maintain the upper surface of the closure frame 8 in contact with the bottom surface of the precast block 2 without applying an upward force F to the closure frame 8 when the precast block 2 and the closure frame 8 are moved downward to the predetermined installation height. Specifically, for example, the contact maintaining means 9 can be a locking device (a device with a function similar to a door stop stay) that stops the closure frame 8 at the predetermined installation height when the precast block 2 and the closure frame 8 are moved downward to the predetermined installation height.

[0069] In the present invention, it is possible to adopt a configuration in which only the elastic member 9a is used as the contact maintaining means 9, as in the embodiment illustrated in Figures 1 to 7, or a configuration in which only the buoyant body 9b is used as the contact maintaining means 9, as in the embodiment illustrated in Figures 8 and 9. In the present invention, for example, it is also possible to adopt a configuration in which both the elastic member 9a and the buoyant body 9b are used as the contact maintaining means 9. Furthermore, the combination of the contact maintaining means 9 and the method of supporting the closure frame body 8 with the tensioned suspension member 10 is not limited to the combinations exemplified above, and any appropriate combination can be used.

[0070] Furthermore, the shape and size of the superstructure 1 (precast blocks 2) are not limited to the above-described embodiment, and various other configurations are possible. While this embodiment illustrates the construction of a superstructure 1 fixed to a single support 40, it is also possible to construct a superstructure 1 extending across multiple supports 40 by, for example, fabricating a precast block 2 with multiple through-holes 3 and loosely inserting separate supports 40 into each through-hole 3. It is also possible to construct a superstructure 1 that is L-shaped, polygonal, or circular in top view, for example. While the above-described embodiment illustrates the case where the supports 40 are piles, similar construction methods and effects can be achieved even when the supports 40 are sheet piles. [Explanation of symbols]

[0071] 1 Superstructure 2 Precast blocks 3 Through holes 4 Block letters 5 Sheath tube 6 Beam members 6a Upper connection part 7 Hanging hardware 8 Closure frame 8a Gap filling material 8b Intervening member 8c Hinge part 8d Connecting part 8e Lower connection 9 Contact maintenance means 9a Elastic member 9b Buoyant body 10 Hanging member 11 Fixed part 11a Hinge part 11b Connection part 12 Connection 12a Hinge part 12b Connection part 13 Binding jig 14 Fasteners 20 Filling material 20a First filling material 30 Divider 40 Support WB Underwater ground WL water surface position

Claims

1. A blocking mechanism that blocks the gap between the outer circumferential surface of the support and the insertion hole when inserting a support erected on the bottom ground into the insertion hole of a precast block that is a component of the superstructure, and filling and solidifying a fill material between the outer circumferential surface of the support and the inner circumferential surface of the insertion hole, a closing frame body fitted onto the support body, movable in the up and down direction, and having a surface facing the gap; A blocking mechanism characterized by having an abutment maintenance means that generates an upward force that resists the pushing when the precast block abuts the blocking frame body from above and pushes down the blocking member, and uses the upward force to keep the blocking frame body abutted against the precast block.

2. the contact maintaining means is an elastic member connected between the closure frame and an upper portion of the support member located above the closure frame, The closing mechanism according to claim 1 , wherein the upward force is an elastic force generated in the elastic member by the pressing.

3. the contact maintaining means is a buoyant body provided on the closure frame, 2. The closing mechanism according to claim 1, wherein the upward force is a buoyancy generated in a portion of the buoyant body that is submerged below the water surface due to the pressing.

4. A string-like or cord-like hanging member is provided, A closure mechanism described in any one of claims 1 to 3, characterized in that one end of the hanging member is fixed to the closure frame body in advance, and after the pressing, the other end is fixed in a tensile state to the support body or the precast block.

5. 4. The closing mechanism according to claim 1, further comprising a gap filling member disposed annularly on the closing frame so as to abut against the outer peripheral surface of the support body.

6. 4. The closing mechanism according to claim 1, further comprising an intervening member for filling a gap that occurs when the closing frame is fitted onto the support body.

7. 7. The closing mechanism according to claim 6, wherein the intervening member is a member that reduces friction with the outer peripheral surface of the support body.

8. a step of inserting a support body to be erected on the bottom ground into an insertion hole of a precast block which is a component of the superstructure; a step of closing a gap between an outer peripheral surface of the support body and the insertion hole using a closing mechanism; a step of filling a filler material between an outer peripheral surface of the support body and an inner peripheral surface of the insertion hole and solidifying the filler material; The closing mechanism includes: a closing frame body fitted onto the support body, movable in the up and down direction, and having a surface facing the gap; A method for constructing a superstructure, characterized in that it comprises a contact maintenance means that generates an upward force that resists the pushing when the precast block abuts against the blocking frame body from above and pushes down the blocking member, and uses the upward force to keep the blocking frame body abutted against the precast block.

Images