Repair method for underwater concrete structures

Abstract

To provide a method for repairing an underwater concrete structure, which can easily and reliably repair a portion requiring repair and reduces the risk of repair filler falling off after repair. [Solution] A method for repairing an area requiring repair that has been formed on the bottom surface 1a of an underwater concrete structure 1, comprising: a filling space forming process in which the area requiring repair is chipped away to form a filling space A for repair filler 4 having an opening 3a on the bottom surface 1a of the concrete structure 1; a filling space shaping process in which an inclined surface 3b that widens upward is formed around the entire circumference or part of the inner surface of the opening 3a; a repair filler filling process in which the repair filler 4 is filled into the filling space A; and a filling space closing process in which the opening 3a is blocked from below with a bottom plate 5, and a buoyant body 7 filled with air is placed below the bottom plate 5, and the buoyancy of the buoyant body 7 presses the bottom plate 5 against the opening 3a.

Description

[Technical Field]

[0001] The present invention relates to a method for repairing underwater concrete structures, and more particularly to a method for repairing areas that require repair due to material separation or the like of concrete cast underwater. [Background technology]

[0002] Conventionally, some underwater concrete structures, such as quay walls, are constructed by pouring concrete underwater using a concrete pumping method or the like. Figure 9 shows an example of such an underwater concrete structure. The concrete structure a shown in the figure is a structure that constitutes a quay wall, and is constructed so that all or part of it is submerged underwater. It is constructed by pouring concrete on the surface side (underwater side) of steel sheet piles b that form the quay wall surface. Specifically, the concrete structure a shown in the figure is constructed by placing formwork for pouring concrete (bottom and side plates, not shown) on the surface side of steel sheet piles b and pouring concrete into this formwork. The symbol c in the figure indicates reinforcing bars arranged in the concrete structure a.

[0003] However, underwater concrete structure a constructed in this manner may develop areas requiring repair work (areas requiring repair), such as cavities forming inside the concrete structure a due to material separation of the poured concrete, or peanut blotches where aggregate is concentrated on the surface of the concrete structure a. For areas requiring repair due to such poor construction, repair work is carried out by filling the areas requiring repair with repair filler, as shown in Patent Document 1, for example. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-184715 Summary of the Invention [Problem to be solved by the invention]

[0005] However, such conventional repair methods have the following problems, and improvements are desired.

[0006] In conventional repair methods, for example, when a cavity opens onto the bottom of an underwater concrete structure, the cavity is filled with repair filler, and a bottom plate is attached to the opening of the cavity using anchor bolts or other fixing hardware to prevent the filler from leaking until the filler hardens.However, there is a problem in that it is not easy to attach a bottom plate by going under a concrete structure underwater, and the work of attaching the bottom plate requires skill.

[0007] Furthermore, filling cavities at the bottom of underwater concrete structures with filler is not only done underwater, but also requires filling from the bottom up, making it difficult to accurately grasp the size and depth of the cavity. As a result, the filler is often filled based on a rough estimate, which can result in an insufficient amount of filler being used. This insufficient filling of filler not only leaves cavities in the concrete structure, but is also a factor in the fallout and dropping of filler after repairs.

[0008] The present invention has been made in consideration of these problems, and its purpose is to provide a method for repairing underwater concrete structures that allows for easy and reliable repair of areas requiring repair by filling with repair filler, and reduces the risk of the repair filler falling off after repair. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the method for repairing underwater concrete structures according to the present invention is a method for repairing an area requiring repair formed on the bottom surface of an underwater concrete structure, and is characterized by comprising: a filling space forming process for chipping out the area requiring repair to form a filling space for repair filler having an opening on the bottom surface of the concrete structure; a filling space shaping process for forming an inclined surface that expands upward around the entire circumference or part of the inner surface of the opening; a repair filler filling process for filling the filling space with the repair filler; and a filling space closing process for blocking the opening from below with a bottom plate, placing a buoyant body filled with air below the bottom plate, and pressing the bottom plate against the opening using the buoyancy of the buoyant body.

[0010] In this invention, when repairing a repair-requiring area formed on the bottom surface of an underwater concrete structure, the repair-requiring area is first scraped to form a filling space for the repair filler (filling space forming process). The filling space for the repair filler has an opening on the bottom surface of the concrete structure. After the filling space for the repair filler is formed, the entire circumference or part of the inner periphery of the opening is scraped to form an inclined surface on the inner periphery of the opening (filling space shaping process). This inclined surface widens upward. By forming such an inclined surface, the inclined surface functions as a stopper that prevents the hardened repair filler from falling out or dropping out of the filling space. This prevents the hardened repair filler from falling out or dropping out of the opening.

[0011] Once the inclined surface is formed at the opening of the filling space, the filling space is then filled with repair filler (filling process). Once the repair filler has been filled, the opening of the filling space filled with the repair filler is then blocked from below with a bottom plate (filling space blocking process). In this process, in the present invention, a buoyant body filled with air is placed below the bottom plate, and the buoyancy of this buoyant body is used to press the bottom plate against the opening of the filling space, thereby maintaining the blocked state of the opening. Therefore, repair workers can easily and reliably block the filling space filled with repair filler without having to perform the cumbersome task of fixing the bottom plate underwater using fastening hardware or the like.

[0012] In a preferred embodiment of the present invention, a resin sheet material is interposed between the opening and the bottom plate. By interposing the resin sheet material between the opening and the bottom plate in this way, it is possible to prevent the repair filler material from adhering to the bottom plate when removing the bottom plate after the repair filler material has hardened, and the removal of the bottom plate can be carried out easily and quickly.

[0013] In addition, in another embodiment of the method for repairing underwater concrete structures according to the present invention, when the filling space has a side opening that opens to the side of the concrete structure, the filling space closing process is characterized in that it includes a process of closing the opening from below with a bottom plate, placing a buoyant body filled with air below the bottom plate, and pressing the bottom plate against the opening using the buoyancy of the buoyant body, as well as a process of closing the side opening with a side plate.

[0014] This invention discloses a repair method in which the filling space formed in the filling space forming step for the repair filler has a side opening that opens to the side of the concrete structure. In this case, in the filling space closing step after filling the filling space with the repair filler, the opening on the bottom of the concrete structure is closed with a bottom plate having a buoyant body filled with air at its bottom, and side plates are placed over the side openings to close the side openings, thereby preventing the repair filler from leaking out of the side openings.

[0015] In a preferred embodiment of the present invention, a resin sheet material is interposed between the opening and the bottom plate and between the side opening and the side plate. By interposing a resin sheet material between the opening and the bottom plate and between the side opening and the side plate, respectively, it is possible to prevent the repair filler from adhering to the bottom plate and the side plate, and the bottom plate and the side plate can be easily and quickly removed.

[0016] In another preferred embodiment of the underwater concrete structure repair method according to the present invention, the step of filling the repair filler includes filling the filling space with a volume of the repair filler that exceeds the volume of the filling space so that the repair filler overflows from the filling space. By filling the repair filler so that the repair filler overflows from the filling space in this way, it is possible to avoid an insufficient volume of the repair filler and to prevent the occurrence of voids due to insufficient filling of the repair filler.

[0017] In a preferred embodiment of the present invention, in the filling space closing step, when the opening is closed from below with the bottom plate, it is confirmed whether the repair filler protrudes from the opening, and if the repair filler does not protrude from the opening, the repair filler filling step is executed again. In this way, by determining whether or not to execute the repair filler filling step again based on whether or not the repair filler protrudes from the opening, it is possible to reliably and sufficiently fill the repair filler even in underwater work where sufficient visibility is often not ensured, and to reliably repair the area requiring repair. [Effects of the Invention]

[0018] The method for repairing underwater concrete structures according to the present invention is a method for repairing areas that need repair and are formed on the bottom surface of an underwater concrete structure, and includes a filling space forming process of chipping away the area that needs repair to form a filling space for repair filler having an opening on the bottom surface of the concrete structure, a filling space shaping process of forming a slope that widens upward around the entire circumference or part of the inner surface of the opening, a repair filler filling process of filling the filling space with the repair filler, and a filling space closing process of closing the opening from below with a bottom plate and placing a buoyant body filled with air below the bottom plate, and pressing the bottom plate against the opening using the buoyancy of the buoyant body.Therefore, the area that needs repair can be easily and reliably repaired by filling the repair filler.

[0019] In particular, according to the present invention, an inclined surface that widens upward is formed on the inner circumferential surface of the opening of the filling space into which the repair filler is filled, so that the repair filler that has been filled into the filling space and has hardened can be effectively prevented from dropping out or falling off from the opening. As a result, the repair filler can be reliably filled into the area requiring repair, and the repaired area will not drop out or fall off, so that the repaired condition can be maintained in good condition for a long period of time.

[0020] In addition, according to the present invention, when the opening of the filling space for repair filler is blocked from below with a bottom plate, a buoyant body filled with air is placed under the bottom plate, and the buoyancy of this buoyant body is used to block the opening of the filling space with the bottom plate, thereby avoiding troublesome work such as attaching fixing brackets underwater, and even workers who are not skilled in underwater work can easily and reliably perform the filling work of repair filler. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a cross-sectional view illustrating the work content of a filling space forming process for a portion requiring repair in the underwater concrete structure repair method according to the present invention. FIG. [Figure 2] 10 is a cross-sectional view illustrating the work content of the filling space shaping process for the area requiring repair in the underwater concrete structure repair method. FIG. [Figure 3] 10 is a cross-sectional view illustrating the work content of the filling process and the filling space closing process for the area requiring repair in the underwater concrete structure repair method. FIG. [Figure 4] 10 is a cross-sectional view illustrating the work content of the filling space closing process for the area requiring repair in the underwater concrete structure repair method. FIG. [Figure 5] FIG. 10 is a cross-sectional view illustrating the work content of a filling space forming step for a portion requiring repair in a second embodiment to which the underwater concrete structure repair method according to the present invention is applied. [Figure 6] FIG. 10 is a cross-sectional view illustrating the work content of the filling space shaping step for the area requiring repair in the second embodiment to which the underwater concrete structure repair method is applied. [Figure 7] 10 is a cross-sectional view illustrating the work contents of the filling step for the area requiring repair and the filling space closing step in a second embodiment to which the underwater concrete structure repair method is applied. FIG. [Figure 8] FIG. 10 is a cross-sectional view illustrating the work content of the filling space closing step for the area requiring repair in the second embodiment to which the underwater concrete structure repair method is applied. [Figure 9] FIG. 1 is a partially cutaway perspective view of an example of an underwater concrete structure. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of the present invention will be described in detail with reference to Figures 1 to 8. In this specification and drawings, components having substantially the same functional configurations will be denoted by the same reference numerals, and duplicated explanations will be omitted.

[0023] The underwater concrete structure repair method of the present invention relates to a method for repairing a concrete structure (underwater concrete structure) that is wholly or partially submerged underwater, such as a concrete quay, and more specifically, it is a repair method for repairing areas that require repair due to poor construction caused by separation of concrete materials, such as cavities that open to the bottom of the underwater concrete structure or peanut boards where aggregate is concentrated on the bottom of the underwater concrete structure.

[0024] Embodiment 1 A first embodiment of the present invention will be described with reference to FIGS. 1 to 4 is a structure that constitutes a quay wall of a port, and as shown in the figures, the concrete structure 1, which is roughly rectangular, is formed on the sea side (underwater side) of steel sheet piles 2 that are placed on the land side. This concrete structure 1 is formed by placing formwork (bottom plates and side plates) for pouring concrete (not shown) underwater adjacent to the steel sheet piles 2 and pouring concrete into this formwork.

[0025] 1 illustrates a state in which a cavity 3 (a portion requiring repair) due to poor construction has appeared on the bottom surface 1a of this concrete structure 1. To repair this cavity 3, the repair work is carried out in the following procedure.

[0026] (1) In carrying out repair work, first, a repair worker dives underwater to check the position, size, etc. of cavity 3, and then chips out the inside of cavity 3 to form a filling space A for repair filler 4 (filling space forming process: see Figure 1). Specifically, cavity 3 is not necessarily in a state suitable for filling with repair filler 4, so the inside of cavity 3 is machined to a shape suitable for filling with repair filler 4, for example, by chipping out the inside of cavity 3. For example, if opening 3a of cavity 3 is too narrow to fill with repair filler 4, opening 3a is widened slightly, or if the inner surface of cavity 3 is brittle and prone to crumbling, the brittle portion is chipped off, etc., to prepare cavity 3 in a state suitable for filling with repair filler 4.

[0027] (2) After the formation of the filling space A is completed, the repair worker next forms a predetermined inclined surface 3b on the inner peripheral surface of the opening 3a of the filling space A (filling space shaping process: see FIG. 2). This inclined surface 3b constitutes a stopper that prevents the repair filler 4, which will be filled in the filling process described below, from dropping out of the filling space A, and is formed as an inclined surface that widens upward and outward around the entire circumference or part of the opening 3a of the filling space A (cavity 3). That is, the repair worker scrapes off the inner peripheral surface of the opening 3a of the filling space A to form the inclined surface 3b on the inner peripheral surface of the opening 3a. Note that this inclined surface 3b is preferably formed around the entire circumference of the opening 3a, but is formed in at least one or more locations, preferably multiple locations, of the opening 3a.

[0028] (3) After the formation of the inclined surface 3b is completed, the filling space A is filled with the repair filler 4 (repair filler filling step: see FIG. 3). As the repair filler 4, a resin filler that has excellent water resistance and can be used underwater, such as epoxy resin putty, is preferably used.

[0029] As shown in Fig. 3, the repair filler 4 is filled in such a manner that the volume of the repair filler 4 exceeds the capacity of the filling space A, so that the filling space A is completely filled with the repair filler 4, but the repair filler 4 slightly overflows from the opening 3a of the filling space A. Specifically, as shown in Fig. 3, the repair filler 4 filled in the filling space A is filled so that it overflows from the bottom surface 1a of the concrete structure 1 by several centimeters. By filling the repair filler 4 so that it overflows from the opening 3a in this way, it is possible to avoid insufficient filling of the repair filler 4 and to avoid leaving voids in the filling space A.

[0030] (4) Once the filling of the repair filler 4 is complete, the repair worker then closes the opening 3a of the filling space A filled with the repair filler 4 from below with a bottom plate 5 until the repair filler 4 hardens, and places a buoyant body 7 filled with air under the bottom plate 5, using the buoyancy of the buoyant body 7 to keep the bottom plate 5 pressed against the opening 3a (filling space closing process: see Figures 3 and 4).

[0031] Here, a plate material that can completely cover the opening 3a, i.e., a plate material that is larger than the opening area of ​​the opening 3a, is preferably used as the bottom plate 5. In addition, a plate material made of a material that floats on water, such as a wooden plate or a polypropylene resin plate, is preferably used as the plate material.

[0032] To close the opening 3a, a resin sheet material 6 is interposed between the opening 3a of the filling space A and the bottom plate 5 (see FIG. 3). The sheet material 6 is a member for preventing the repair filler 4 from adhering to the bottom plate 5. In this embodiment, a plastic bag 61 large enough to accommodate the bottom plate 5 is used. That is, the bottom plate 5 is accommodated in the plastic bag 61, and the bottom plate 5 together with the plastic bag 61 is abutted against the opening 3a, thereby interposing the plastic bag 61 (sheet material 6) between the opening 3a and the bottom plate 5. By using the plastic bag 61 as the sheet material 6 in this way, the sheet material 6 can be easily and quickly interposed between the opening 3a and the bottom plate 5. In particular, in underwater work, the simplification of the interposition work of the sheet material 6 can contribute to a significant reduction in the overall work time required to repair the area requiring repair. When attaching the plastic bag 61 to the bottom plate 5, it is desirable to smooth out any wrinkles by pulling evenly the open end of the plastic bag 61 so that the part facing the opening 3a does not get wrinkled. This makes it easier to peel off the bottom plate 5 after repairs are complete, and allows the bottom plate 5 to be removed quickly.

[0033] Furthermore, when closing the opening 3a with the bottom plate 5, the repair worker confirms that the repair filler 4 is not spilling out of the opening 3a. As described above, in this embodiment, the repair filler 4 is filled in a volume that exceeds the volume of the filling space A. Therefore, if the repair filler 4 is filled as specified, the repair filler 4 will be spilling out of the opening 3a (see FIG. 4). When closing the opening 3a with the bottom plate 5, the repair worker visually checks whether the repair filler 4 is spilling out between the bottom plate 5 and the opening 3a. If the visual check shows that the repair filler 4 is not spilling out of the opening 3a, the repair worker removes the bottom plate 5 and repeats the repair filler filling process. On the other hand, if the visual check shows that the repair filler 4 is spilling out of the opening 3a, the repair worker places a buoyancy body 7 under the bottom plate 5 (see FIG. 4). In this way, by determining whether or not to perform the repair filler filling process again based on whether or not the repair filler 4 is protruding from the opening 3a, the repair filler 4 can be filled reliably and sufficiently even when working underwater, where it is often difficult to ensure sufficient visibility.

[0034] The opening 3a is closed with the bottom plate 5 by placing a buoyant body 7 filled with air under the bottom (lower side) of the bottom plate 5 and using the buoyancy of the buoyant body 7 to press the bottom plate 5 against the opening 3a (see FIG. 4). Specifically, a polyethylene tank 71 filled with air is preferably used as the buoyant body 7. The illustrated example illustrates a case in which two polyethylene tanks 71, 71 are used to press the bottom plate 5 against the opening 3a. The number and capacity of the polyethylene tanks 71 used can be changed as needed, but in this embodiment, the buoyancy of the polyethylene tanks 71 can be used to maintain the bottom plate 5 pressed against the opening 3a. Therefore, even if the repair worker leaves the site after placing the polyethylene tanks 71 under the bottom plate 5, the bottom plate 5 remains closed.

[0035] Here, a polyethylene tank 71 is used as the buoyancy body 7 because the polyethylene tank 71 is relatively easy and inexpensive to obtain. Furthermore, with a polyethylene tank 71, the buoyancy can be easily reduced by pouring water into the tank, and by reducing the buoyancy, the bottom plate 5 can be easily separated from the bottom surface 1a of the concrete structure 1. Note that it is also possible to use a tank or bag other than the polyethylene tank 71 as the buoyancy body 7, as long as it has a structure that can push up the bottom plate 5 by buoyancy.

[0036] (5) Then, once the repair filler 4 has hardened, the bottom plate 5 that had been blocking the opening 3a is removed, completing the repair work. When removing the bottom plate 5, the plastic container 71 that had been placed underneath the bottom plate 5 is removed from below the bottom plate 5, thereby releasing the buoyancy that had been pressing the bottom plate 5 toward the opening 3a, making it possible to easily pull away the bottom plate 5 that had been blocking the opening 3a.

[0037] As described above, according to the repair method for underwater concrete structures shown in this embodiment, when repairing an area requiring repair formed on the bottom surface 1a of an underwater concrete structure 1, the method includes a filling space forming process of chipping the area requiring repair to form a filling space A for repair filler having an opening 3a on the bottom surface 1a of the concrete structure 1, a filling space shaping process of forming an inclined surface 3b that expands upward around the entire circumference or part of the inner surface of the opening 3a, a repair filler 4 filling process of filling the filling space A with the repair filler 4, and a filling space closing process of closing the opening 3a from below with a bottom plate 5 and placing a buoyant body 7 filled with air under the bottom plate 5 so that the buoyancy of the buoyant body 7 presses the bottom plate 5 against the opening 3a. Therefore, the repair of the area requiring repair by filling the repair filler 4 can be easily and reliably performed.

[0038] Furthermore, according to this embodiment, an inclined surface 3b that widens upward is formed on the inner circumferential surface of the opening 3a of the filling space A into which the repair filler 4 is filled, so that the hardened repair filler 4 that has been filled into the filling space A can be effectively prevented from dropping off or falling out of the opening 3a. As a result, the repair filler 4 can be reliably filled into the area requiring repair, and the repaired area will not drop off or fall out, so that the good condition after repair can be maintained for a long period of time.

[0039] Furthermore, according to this embodiment, when the opening 3a of the filling space A of the repair filler 4 is blocked from below with the bottom plate 5, a buoyant body 7 filled with air is placed under the bottom plate 5, and the buoyancy of this buoyant body 7 is used to block the opening 3a of the filling space A with the bottom plate, so that the opening 3a can be blocked without performing troublesome work underwater, and even workers who are not skilled in underwater work can easily and reliably perform repair work using the repair filler 4.

[0040] Embodiment 2 Next, a second embodiment of the method for repairing an underwater concrete structure according to the present invention will be described with reference to FIGS.

[0041] The repair method for underwater concrete structures shown in the second embodiment is a repair method in which the shape of the filling space A of the repair filler 4 is modified, as shown in Fig. 5, and the configuration of the concrete structure 1 is the same as in the above-mentioned embodiment 1. Therefore, the same reference numerals are used for the parts that have the same configuration, and the description thereof will be omitted.

[0042] The method for repairing an underwater concrete structure shown in this embodiment is applied when the filling space A for the repair filler formed in the filling space forming step has, in addition to the opening 3a opening in the bottom surface 1a of the concrete structure 1, a side opening 3c opening in the side surface 1b of the concrete structure 1. Specifically, this method is applied when, in the filling space forming step, the opening 3a is formed in the bottom surface 1a of the concrete structure 1 and the side opening 3c is formed in the side surface 1b of the concrete structure 1 when the part to be repaired formed in the bottom surface 1a of the underwater concrete structure 1 is chipped away to form the filling space A for the repair filler 4.

[0043] After the filling space forming process is completed, the process moves to the filling space shaping process (see FIG. 6). In the filling section shaping process, as in the first embodiment described above, an inclined surface 3b is formed on the inner peripheral surface of the opening 3a of the filling space A. However, as shown in the figure, if a part of the opening 3a is a side opening 3c that opens to the side surface 1b of the concrete structure 1, an inclined surface 3b is formed on a part of the opening 3a. Note that even in this case, the opening 3a is formed in at least one location, and preferably in multiple locations.

[0044] After the filling space shaping step is completed, the process moves to the filling step of the repair filler 4 (see FIG. 7). In the filling step, the repair filler 4 is filled in an amount that exceeds the capacity of the filling space A, as in the first embodiment described above. However, in this embodiment, as shown in FIG. 7, since the filling space A is open to both the bottom surface 1a and the side surface 1b of the concrete structure 1, it is preferable that the filling of the repair filler 4 is carried out in parallel with the next step, the filling space closing step.

[0045] Specifically, since the filling space A is open to the bottom surface 1a and the side surface 1b of the concrete structure 1, in the filling space closing process, the opening 3a opening on the bottom surface 1a of the concrete structure 1 is closed from below with the bottom plate 5, and the side opening 3c opening on the side surface 1b of the concrete structure 1 is closed from the side with the side plate 8. In this embodiment, the bottom plate 5 and the side plate 8 are attached to the concrete structure 1 with anchor bolts 9 as shown in FIG. 8 . However, it is also possible to omit the use of the anchor bolts 9 by, for example, connecting the bottom plate 5 and the side plate 8 in an L-shaped integral configuration. Here, similar to the bottom plate 5, the side plate 8 is preferably made of a plate material that can completely close the side opening 3c, i.e., a plate material that is larger than the opening area of ​​the side opening 3c. Furthermore, the side plate 8 is preferably made of, for example, wood or polypropylene resin.

[0046] When the opening 3a and the side openings 3c are closed by the bottom plate 5 and the side plates 8, resin sheet material 6 is interposed between the opening 3a and the side openings 3c and the bottom plate 5 and the side plates 8, as in the first embodiment described above (see FIG. 7). In the illustrated example, one sheet material 6 is interposed between the opening 3a and the side openings 3c and the bottom plate 5 and the side plates 8, but separate sheet materials 6 may be interposed between the opening 3a and the side openings 3c, respectively. Alternatively, the bottom plate 5 and the side plates 8 may each be housed in a plastic bag 61, as in the first embodiment.

[0047] Also in this embodiment, when the repair worker closes the opening 3a and the side opening 3c with the bottom plate 5 and the side plate 8, the repair worker checks whether the repair filler 4 is spilling out of each of the opening 3a and the side opening 3c, and if the repair filler 4 is not spilling out, the repair worker performs the filling process of the repair filler 4 again. On the other hand, if the repair filler 4 is spilling out, the buoyancy body 7 is placed under the bottom plate 5 (see FIG. 8) and maintained in this state until the repair filler 4 hardens. In this way, the buoyancy body 7 acts to push up the bottom plate 5, so the bottom plate 5 will not fall off and it is possible to wait for the repair filler 4 to harden.

[0048] Thus, according to the underwater concrete structure repair method shown in the second embodiment, when the filling space A has a side opening 3c that opens into the side surface 1b of the concrete structure 1, the filling space closing process includes a process of closing the opening 3a from below with a bottom plate 5, placing an air-filled buoyant body 7 below the bottom plate 5, and pressing the bottom plate 5 against the opening 3a using the buoyancy of the buoyant body 7, as well as a process of closing the side opening 3c with a side plate 8.Therefore, in addition to the technical effects shown in the above-mentioned embodiment 1, it is possible to prevent the repair filler material 4 from leaking to the outside through the side opening 3c.

[0049] The above-described embodiments are merely preferred embodiments of the present invention, and the present invention is not limited to these, and various design modifications are possible within the scope of the present invention.

[0050] For example, in the above-described embodiment, the method for repairing underwater concrete structures according to the present invention is shown as being applied to repairing areas of the concrete structure 1 that require repair due to poor construction, but if the area requiring repair is formed on the bottom surface of the underwater concrete structure 1, it can also be applied to repairing areas that require repair other than those due to poor construction (for example, cracks due to deterioration over time).

[0051] In the above-described embodiment, wooden boards or polypropylene resin boards are used as the bottom board 5 and the side boards 8, but boards made of other materials can also be used as long as they can cover the opening 3a and the side opening 3c. In the above-described embodiment, a vinyl bag 61 is used as the sheet material 6, but resin sheets or resin bags other than vinyl can also be used as long as the sheet material is made of a material to which the repair filler 4 does not adhere strongly.

[0052] Furthermore, in the above-described embodiment, the case where the closing state of the opening 3a by the bottom plate 5 is maintained solely by the buoyancy of the buoyant body 7 is shown, but it is also possible to configure the closing state of the opening 3a to be maintained by using both the buoyancy of the buoyant body 7 and the fixing metal fittings that attach the bottom plate 5 to the concrete structure 1. In this case, the buoyancy of the buoyant body 7 is used supplementarily to close the opening 3a, so it becomes possible to use fixing metal fittings with a simple configuration that are easy to attach to the concrete structure 1 as fixing metal fittings to the concrete structure 1.

[0053] Furthermore, in the above-described embodiment, a concrete structure that constitutes a quay wall of a port was used as an example of concrete structure 1, but the present invention can of course also be applied to the repair of concrete structures other than quay walls, as long as the concrete structure is submerged in water in whole or in part. [Explanation of symbols]

[0054] 1. Concrete structures 1a Bottom of concrete structure 1b Side of concrete structure 2 Steel sheet piles 3 Cavity (area requiring repair) 3a opening 3b Slope 3c Side opening 4 Repair filler 5 Bottom plate 6 Sheet material 61 Plastic Bags 7 Buoyancy body 71 Poly tank 8 Side Panel 9 anchor bolts

Claims

1. A method for repairing a part requiring repair formed on the bottom surface of an underwater concrete structure, comprising: a filling space forming step of chipping the portion to be repaired to form a filling space for a repair filler having an opening on the bottom surface of the concrete structure; a filling space shaping step of forming an inclined surface expanding upward on the entire circumference or a part of the inner circumferential surface of the opening; a repair filler filling step of filling the filling space with the repair filler; a filling space closing step of closing the opening from below with a bottom plate, disposing a buoyant body filled with air under the bottom plate, and pressing the bottom plate against the opening by the buoyancy of the buoyant body. A method for repairing an underwater concrete structure, comprising:

2. In the case where the filling space has a side opening that opens to a side surface of the concrete structure, The filling space closing step includes a step of closing the opening from below with a bottom plate, placing a buoyant body filled with air under the bottom plate, and pressing the bottom plate against the opening by the buoyancy of the buoyant body, as well as a step of closing the side opening with a side plate.

2. The method for repairing an underwater concrete structure according to claim 1, wherein the method comprises:

3. A resin sheet material is interposed between the opening and the bottom plate.

2. The method for repairing an underwater concrete structure according to claim 1, wherein the method comprises:

4. A resin sheet material is interposed between the opening and the bottom plate and between the side opening and the side plate.

3. The method for repairing an underwater concrete structure according to claim 2, wherein the method comprises:

5. The filling step of the repair filler includes filling the filling space with the repair filler in an amount exceeding the volume of the filling space so that the repair filler overflows from the filling space.

5. A method for repairing an underwater concrete structure according to claim 1, wherein the underwater concrete structure is a submerged concrete structure.

6. In the filling space closing step, when the opening is closed from below with the bottom plate, it is confirmed whether the repair filler protrudes from the opening, and if the repair filler does not protrude from the opening, the filling step of the repair filler is performed again.

6. The method for repairing an underwater concrete structure according to claim 5.

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