Method for Drilling a Concrete Structure

Abstract

To reinforce a structure in which an open hole is penetrated with efficiency and effectively and avoid a harmful effect by drilling to the structure.SOLUTION: In a drilling method of a concrete structure 1 for forming an open hole in the concrete structure by a cutter of a drill, a reinforcement step of adhering a reinforcement sheet 10 with reinforcement fiber to an exterior surface area 5 to be reinforced on an outer peripheral side of a drilling corresponding part 1A at an exterior surface 1a of the structure 1 is performed before performing a drilling work step by the drill.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a drilling technique required, for example, when performing pipeline addition work in a water storage tank such as an existing reinforced concrete water purification tank or water distribution tank, or pipe connection work accompanying the addition of a reinforced concrete water storage area. Specifically, the present invention relates to a method for drilling a concrete structure in which a through hole is formed by a cutter of a drilling machine in a concrete structure,

Background Art

[0002] In a conventional method for drilling a concrete structure, as shown in Patent Document 1, a connecting flange on one end side of a short pipe through which a cylindrical cutter of a drilling machine can pass is fixed to a portion corresponding to the drilling on the outer surface of the structure in a watertight state with bolts. A drilling machine is attached to the connecting flange on the other end side of the short pipe via a shut-off valve. The cutter of this drilling machine is sent into the short pipe from the open shut-off valve, and a through hole is formed at a portion corresponding to the drilling of the structure. The cutter storing the columnar section generated by this drilling is extracted from the short pipe and the shut-off valve. Thereafter, the shut-off valve is closed and the drilling machine is removed.

[0003] In the above-described method for drilling a concrete structure, when a through hole is formed in the concrete structure, the load-bearing capacity of the structure decreases due to the cross-sectional defect. In particular, when the reinforcing bars located at the portion corresponding to the drilling among the reinforcing bars in the structure are cut and removed by the cutter, the load-bearing capacity of the structure significantly decreases. If the strength of the structure is impaired by the cutting and removal of the reinforcing bars at the portion corresponding to the drilling, the safety of the structure on which water pressure, earth pressure, etc. act may not be guaranteed.

[0004] Therefore, as a reinforcing technique for a concrete structure in which a through hole is formed, for example, there is a reinforcing method shown in Patent Document 2. This reinforcing method is a method of reinforcing the outer surface of the structure after the through hole is formed with a plastic sheet provided with reinforcing fibers, and can be simply reinforced in a short construction period without changing the weight of the structure. As one embodiment of the reinforcement method of Patent Document 2, after pasting two plastic sheets of the first set in parallel along one direction with the opening periphery of the through-hole sandwiched between them on the outer surface of the structure, two plastic sheets of the second set are pasted in parallel along a direction orthogonal to the first set of plastic sheets with the opening periphery of the through-hole sandwiched between them. A method is disclosed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] When the above-described reinforcement method of Patent Document 2 is applied to the drilling method of the concrete structure of Patent Document 1, the cutter of the drilling machine is sent into the short pipe from the partition valve that has been opened, and a through-hole is formed at the location corresponding to the drilling of the structure. After that, a plastic sheet is pasted and reinforced on the outer surface of the structure where the connecting flange of the short pipe is bolted. Therefore, a considerable period of time is required from the end of the drilling operation until the reinforcement operation by pasting the plastic sheet is completed, and during that time, there is a possibility of adversely affecting the structure whose load-bearing capacity has been reduced due to the cross-sectional defect caused by the drilling.

[0007] Moreover, the starting position of pasting the plastic sheet is to start from the outer periphery of the flange contact part where the connecting flange of the short pipe is in contact or a position near the outer periphery thereof on the outer surface of the structure. Therefore, the range from the opening periphery of the through-hole to the outer periphery of the connecting flange of the short pipe becomes a non-reinforced area where the plastic sheet does not exist, and there is room for improvement on the reinforcement surface of the structure. Furthermore, since the plastic sheet pasting operation needs to be performed with the short pipe and the shut-off valve attached, the working space is limited, which has the disadvantage of reducing the working efficiency of pasting the plastic sheet.

[0008] In view of this actual situation, the main problem of the present invention is to provide a method for drilling a concrete structure that can efficiently and effectively reinforce a structure in which a through hole is formed and avoid adverse effects on the structure due to drilling.

Means for Solving the Problems

[0009] A first characteristic configuration of the present invention is a method for drilling a concrete structure in which a through hole is formed with a cutter of a drilling machine in a concrete structure, before executing the drilling operation process by the drilling machine, a reinforcement work process of pasting a reinforcement sheet provided with reinforcing fibers on the outer surface region to be reinforced on the outer periphery side of the portion corresponding to the drilling on the outer surface of the structure is executed.

[0010] According to this configuration, before attaching a short pipe, a shut-off valve, etc. for executing the drilling operation process, a reinforcement work process by pasting a reinforcement sheet provided with reinforcing fibers is executed on the outer surface region to be reinforced on the outer periphery side of the portion corresponding to the drilling on the outer surface of the structure. Therefore, since the drilling operation is executed after the reinforcement work of the structure is completed, adverse effects on the structure due to drilling can be avoided. Moreover, the reinforcement sheet can be pasted from the position corresponding to the opening periphery of the through hole over the entire area of the outer surface region to be reinforced. Furthermore, since the working space is not restricted by a short pipe, a shut-off valve, etc., the concrete structure can be efficiently and effectively reinforced.

[0011] A second characteristic configuration of the present invention is that the amount of the reinforcement sheet used in the reinforcement work process is set to an amount that satisfies the Young's modulus × cross-sectional area of the reinforcement sheet equivalent to the Young's modulus × cross-sectional area of the reinforcing bar that is located at the portion corresponding to the drilling and cut and removed among the steel reinforcements in the structure.

[0012] According to this configuration, even when the reinforcing bars located at the perforation-equivalent positions among the reinforcing bars in the concrete structure are cut and removed, the amount of the reinforcing sheet used is set to an amount that satisfies the Young's modulus × cross-sectional area of the reinforcing sheet equivalent to the Young's modulus × cross-sectional area of the reinforcing bars to be cut and removed. Therefore, the concrete structure can be firmly reinforced with the tensile strength of the cut and removed reinforcing bars or higher tensile strength.

[0013] The third characteristic configuration of the present invention includes a hanging work process for hanging the perforation-equivalent position of the structure from the outer surface until a part of the reinforcing bars in the structure is exposed. The hanging work process is to be executed before the reinforcement work process.

[0014] According to this configuration, by performing the hanging work process and hanging the perforation-equivalent position on the outer surface of the concrete structure until a part of the reinforcing bars in the concrete structure is exposed, the volume of the chips cut by the cutter of the perforator is reduced by the amount of the hanging holes, and the load burden at the end of the perforation acting on the cutter can be reduced. Furthermore, if the reinforcing bars exposed in the hanging holes are cut and removed in advance before the perforation work process, the perforation load of the cutter can be reduced. Moreover, it is possible to avoid the adhesion of dust during the hanging work on the surface of the reinforcing sheet layer formed by pasting the reinforcing sheet, like the case of performing the hanging work process after the reinforcement work process, and then the subsequent work can be facilitated and the efficiency can be improved.

[0015] The fourth characteristic configuration of the present invention is that, among the reinforcing sheet layers formed by pasting the reinforcing sheets, on the outer peripheral side of the flange contact part where the connecting flange of the short pipe into which the cutter of the perforator can be inserted abuts, there is an additional pasting reinforcement work process of pasting a reinforcing sheet for reinforcement for hole processing for bolting the connecting flange to the structure.

[0016] According to this configuration, the outer surface region to be reinforced of the structure including the flange contact portion where the connection flange of the short pipe abuts is firmly reinforced with a reinforcing sheet layer formed by pasting a reinforcing sheet. The flange contact portion of this reinforcing sheet layer is drilled for bolting the connection flange of the short pipe to the structure. A part of the reinforcing sheet is lost due to this drilling. However, since a reinforcing sheet for reinforcement against the drilling is pasted on the outer peripheral side of the flange contact portion by performing an additional pasting reinforcement work process, the concrete structure can be reinforced and maintained in a strong state.

[0017] The fifth characteristic configuration of the present invention lies in that there is a smoothing work process for smoothing the flange contact portion where the connection flange of the short pipe into which the cutter of the perforator can be inserted abuts among the reinforcing sheet layers formed by pasting the reinforcing sheet.

[0018] According to this configuration, while firmly reinforcing the outer surface region to be reinforced of the structure including the flange contact portion with a reinforcing sheet layer formed by pasting a reinforcing sheet, in the smoothing work process, the flange contact portion where unevenness, gaps, etc. have occurred in the reinforcing sheet layer is smoothed, so that the joint surface between the flange contact portion and the connection flange of the short pipe can be easily configured in an appropriate surface contact state.

[0019] The sixth characteristic configuration of the present invention lies in that the reinforcing work process includes a first roughening work process for roughening the outer surface of the reinforcing sheet layer located on the inner side in the stacking direction, with one layer being formed by a plurality of reinforcing sheet layers pasted along at least two intersecting directions of the reinforcing sheet.

[0020] According to this configuration, by forming a plurality of reinforcing sheet layers by pasting the reinforcing sheet along at least two intersecting directions, the outer surface region to be reinforced of the concrete structure can be firmly reinforced. Moreover, in the first roughening work process, by roughening the outer surface of the reinforcing sheet layer located on the inner side in the stacking direction, the bonding force with the outer reinforcing sheet layer pasted thereto can be increased.

[0021] The seventh characteristic configuration of the present invention includes a second roughening operation step of roughening the outer surface of the reinforcing sheet layer formed in the reinforcing operation step, and a support concrete construction step of constructing the support concrete that supports the short pipe fixed to the flange contact portion of the structure against the ground in a state of being joined to the outer surface of the reinforcing sheet layer.

[0022] According to this configuration, the short pipe fixed to the flange contact portion of the structure can be firmly supported against the ground by the support concrete against uneven forces due to water pressure and the like. Moreover, since the support concrete is joined to the outer surface of the reinforcing sheet layer, and the outer surface of the reinforcing sheet layer is roughened in the second roughening operation step, the reinforcing sheet layer and the support concrete are firmly bonded, and the structure can be reinforced more firmly.

[0023] The eighth characteristic configuration of the present invention is to execute a pretreatment operation step of smoothing the reinforcing target outer surface area on the outer surface of the structure by primer treatment, base adjustment, etc. between the hanging operation step and the reinforcing operation step.

[0024] According to this configuration, the dust in the hanging operation step adhering to the reinforcing target outer surface area on the outer surface of the concrete structure can be removed by the smoothing treatment in the pretreatment operation step. Moreover, since the reinforcing target outer surface area on the outer surface of the structure where depressions, unevenness, etc. occur can be smoothed, the work of attaching the reinforcing sheet can be efficiently and properly performed.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Mode for Carrying Out the Invention

[0026] Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an example of a concrete structure, and shows a concrete wall 1 made of reinforced concrete of a water storage tank R. Among this concrete wall 1, in a portion below the water surface level of the stored water W, a through hole 6 (see FIGS. 18 and 19) for pipeline connection for taking out the stored water W is formed by a cylindrical cutter (hole saw) 51 of a drilling machine 50 shown in FIGS. 16 to 18. The drilling method of the concrete structure is provided with the following steps [1] to

[16] .

[0027] [1] Foundation construction work process As shown in FIG. 1, in the ground 2 continuous with the concrete wall 1, and in a construction work area corresponding to the pipeline laying route of a short pipe 30 (see FIG. 13) and a shut-off valve 40 (see FIG. 15) to be attached to a drilling corresponding portion 1A of the concrete wall 1, a groove is excavated in a predetermined width in a groove shape. Crushed stones 3 are laid in layers at the bottom of the excavated excavation groove 2A. On the upper part of this crushed stone 3 layer, a reinforced base concrete 4 is constructed. As shown in FIGS. 3 and 4, the lateral width of this base concrete 4 is set to be the same as or substantially the same as the lateral width 5W of a reinforcement target outer surface area 5 that extends in a rectangular shape in the vertical and horizontal directions on the outer peripheral side of the drilling corresponding portion 1A on the outer surface 1a of the concrete wall 1. In the figure, 5H indicates the vertical width of the reinforcement target outer surface area 5. The base concrete 4 constructed by placing and curing the concrete receives the masses of the short pipe 30, the shut-off valve 40, the drilling machine 50, a short pipe support concrete 31 (see FIG. 15) that supports the short pipe 30 against the ground, a shut-off valve support 41 (see FIG. 15) that supports the lower end portion of the shut-off valve 40 against the ground, etc., and prevents the ground subsidence of the construction work area.

[0028] [2] Hanging work process As shown in FIG. 2, a circular hanging range 7 centered on the drilling axis (drilling axis core) X is marked on a drilling corresponding portion 1A of the outer surface 1a of the concrete wall 1. The diameter of this hanging range 7 is set to be the same as or substantially the same as the drilling diameter (outer diameter) of the cutter 51 of the drilling machine 50. The hanging range 7 marked on the outer surface 1a of the concrete wall 1 is hung in a circular shape with a hanging tool. The hanging hole 6A formed in this hanging operation constitutes a part of the through hole 6 penetrating the concrete wall 1. As shown in FIGS. 2 and 3, the depth of the hanging hole 6A is set to a depth at which a part of the outer surface side reinforcing bar 9 arranged at a position close to the outer surface 1a side among the inner and outer reinforcing bars 8 and 9 arranged in the concrete wall 1 is exposed. This hanging operation process is executed before the reinforcement operation process described later.

[0029] By performing the above-described hanging operation process and hanging the perforation equivalent portion 1A on the outer surface 1a of the concrete wall 1 to a state where a part of the reinforcement in the concrete wall 1 is exposed, the volume of the slice cut by the cutter 51 of the perforator 50 is reduced by the amount of the hanging hole 6A, and the load burden at the end of the perforation acting on the cutter 51 can be reduced. Further, when the outer surface side reinforcing bar 9 exposed at the bottom in the hanging hole 6A is cut and removed in advance before the perforation operation process, the perforation load of the cutter 51 can be reduced. Moreover, it is possible to avoid the adhesion of dust during the hanging operation to the surface of the reinforcing sheet 10 attached to the outer surface region 5 to be reinforced of the concrete wall 1, as in the case where the hanging operation process is executed after the reinforcement operation process.

[0030] [3] Substrate adjustment treatment work process As shown in FIG. 3, among the outer surface 1a of the concrete wall 1, an annular flange contact portion 1B where the connecting flange 30 on one end side (upstream side) of the short pipe 30 into which the cutter 51 of the perforator 50 can be inserted abuts from the perforation axis direction, and a region having a horizontal width 5W and a vertical width 5H that spreads in a rectangular shape in the vertical and horizontal directions becomes the outer surface region 5 to be reinforced with the reinforcing sheet 10. A primer treatment is performed on this outer surface region 5 to be reinforced to enhance the adhesiveness with the reinforcing sheet 10 to be attached in the reinforcement operation process described later. After this primer treatment, the grooves 5a, recesses 5b, scratches 5c, etc. on the substrate of the outer surface region 5 to be reinforced are filled with putty, and a substrate adjusting material is applied to the entire substrate of the substrate adjustment target portion, and a substrate adjustment treatment for adjusting the entire substrate to a smooth surface is executed as shown in FIG. 4.

[0031] [4] Reinforcement work process For the outer surface 1a of the concrete wall 1 in the reinforcement target outer surface area 5 where the base adjustment process has been completed, a roughening process is performed to form minute irregularities with a roughening tool. When the roughening process is completed, a cleaning process is executed to remove dust and the like adhering to the outer surface 1a of the concrete wall 1 in the reinforcement target outer surface area 5 with a blower or the like.

[0032] As shown in FIG. 5, before executing the drilling work process by the drill 50, a reinforcement work process is executed in which a reinforcing sheet 10 provided with reinforcing fibers is attached with an adhesive to the reinforcement target outer surface area 5 on the outer peripheral side of the drilling equivalent portion 1A on the outer surface 1a of the concrete wall 1 where the cleaning process has ended. As described above, before attaching the short pipe 30, the shut-off valve 40, etc. for executing the drilling work process, a reinforcement work process by attaching the reinforcing sheet 10 provided with reinforcing fibers is executed for the reinforcement target outer surface area 5, so that the adverse effect on the concrete wall 1 due to drilling can be avoided. Moreover, the reinforcing sheet 10 can be attached from the opening periphery of the lifting hole 6A (through hole 6) or its vicinity position to the entire reinforcement target outer surface area 5. Furthermore, since the working space is not restricted by the short pipe 30, the shut-off valve 40, etc., the concrete wall 1 can be efficiently and effectively reinforced.

[0033] In the present embodiment, as the reinforcing sheet 10, carbon fiber reinforced plastic in which carbon fibers, which are an example of reinforcing fibers, are arranged in one direction to form a sheet-like fabric is used. The amount of the reinforcing sheet 10 used in this reinforcement work process is set to an amount that satisfies the Young's modulus × cross-sectional area of the reinforcing sheet 10 equivalent to the Young's modulus × cross-sectional area of the reinforcing bars 8 and 9 located at the drilling equivalent portion and cut and removed among the steel reinforcements in the concrete wall 1. Therefore, the concrete wall 1 can be firmly reinforced with the tensile strength of the cut and removed reinforcing bars 8 and 9 or more.

[0034] In the reinforcement work process, in the reinforcement target outer surface area 5 of the outer surface 1a of the concrete wall 1, a reinforcement sheet layer in which the reinforcement sheet 10 is attached along at least two intersecting (orthogonal) directions is regarded as one layer, and a plurality of layers (four layers in this embodiment) are formed. With this plurality of layers of reinforcement sheet layers, the reinforcement target outer surface area 5 of the concrete wall 1 can be firmly reinforced. In the method of attaching the reinforcement sheet 10 in this embodiment, the following steps (1) to (4) are executed.

[0035] (1) As shown in FIGS. 5 and 6, among the reinforcement target outer surface areas 5 on the outer surface 1a of the concrete wall 1, the upper side reinforcement target outer surface area 5A above the upper boundary line L1 that horizontally crosses the position corresponding to the upper edge of the opening of the suspension hole 6A (through hole 6) or a position in the vicinity thereof, and the lower side reinforcement target outer surface area 5B below the lower boundary line L2 that horizontally crosses the position corresponding to the lower edge of the opening of the suspension hole 6A (through hole 6) or a position in the vicinity thereof, a room temperature curing impregnating adhesive resin is applied. On the application surface of this impregnating adhesive resin, the first layer of the reinforcement sheet 10 is attached along the horizontal lateral direction. This is the first layer of horizontal attachment process. Next, as shown in FIG. 7, among the reinforcement target outer surface areas 5 where the first layer of horizontal attachment process has been completed, the left side reinforcement target outer surface area 5C on the left side of the left boundary line L3 that vertically crosses the position corresponding to the left edge of the opening of the suspension hole 6A (through hole 6) or a position in the vicinity thereof, and the right side reinforcement target outer surface area 5D on the right side of the right boundary line L4 that vertically crosses the position corresponding to the right edge of the opening of the suspension hole 6A (through hole 6) or a position in the vicinity thereof, a room temperature curing impregnating adhesive resin is applied. On the application surface of this impregnating adhesive resin, the first layer of the reinforcement sheet 10 is attached along the vertical longitudinal direction. This is the first layer of vertical attachment process. By the above-described first layer of horizontal attachment process and the first layer of vertical attachment process, the first layer of reinforcement sheet layer is formed.

[0036] (2) On the reinforcing target outer surface area 5 where the first-layer reinforcing sheet layer is formed, the second-layer horizontal pasting process is performed in the same procedure as the above-described first-layer horizontal pasting process. Next, the second-layer vertical pasting process is performed in the same procedure as the above-described first-layer vertical pasting process. By this second-layer horizontal pasting process and the second-layer vertical pasting process, the second-layer reinforcing sheet layer is formed.

[0037] (3) In this embodiment, there is a number of days between the construction time of the second-layer reinforcing sheet layer and the construction time of the third-layer reinforcing sheet layer, and the adhesive of the second-layer reinforcing sheet layer has hardened. Therefore, a first roughening operation process is performed in which an abrasive such as sand is sprayed onto the surface of the second-layer reinforcing sheet layer, which is an example of the reinforcing sheet layer located on the inner side in the lamination direction, to roughen (finish-grit) it. By roughening the surface of this second reinforcing sheet layer, the bonding strength between layers with the third reinforcing sheet layer can be increased. When this first roughening operation process is completed, the third-layer horizontal pasting process is performed in the same procedure as the above-described first-layer horizontal pasting process on the reinforcing target outer surface area 5 where the second-layer reinforcing sheet layer is formed. Next, the third-layer vertical pasting process is performed in the same procedure as the above-described first-layer vertical pasting process. By this third-layer horizontal pasting process and the third-layer vertical pasting process, the third-layer reinforcing sheet layer is formed.

[0038] (4) On the reinforcing target outer surface area 5 where the third-layer reinforcing sheet layer is formed, the fourth-layer horizontal pasting process is performed in the same procedure as the above-described first-layer horizontal pasting process. Next, the fourth-layer vertical pasting process is performed in the same procedure as the above-described first-layer vertical pasting process. By this fourth-layer horizontal pasting process and the fourth-layer vertical pasting process, the fourth-layer reinforcing sheet layer is formed.

[0039] As described above, when there is an elapsed time (number of days) sufficient for the adhesive applied during the construction of the previous reinforcing sheet layer to harden by the start of construction of the next reinforcing sheet layer, a roughening operation process for roughening the surface of the previous reinforcing sheet layer is performed. When the construction of the previous reinforcing sheet layer and the construction of the next reinforcing sheet layer are on the same day, without performing the above-mentioned roughening operation process, the process proceeds to the construction of the next reinforcing sheet layer.

[0040] [5] First Pattern Overlay Reinforcement Work Process As shown in FIG. 8, in the reinforcing target outer surface area 5 where a four-layer reinforcing sheet layer is formed, on the outer peripheral side of the flange contact part 1B where one end side connecting flange 30A of the short pipe 30 abuts from the perforation axis direction, a first pattern overlay reinforcement work process of attaching a second reinforcing sheet 11 for reinforcement against hole processing for bolting the connecting flange 30A to the concrete wall 1 is executed. The second reinforcing sheet 11 used in this first pattern overlay reinforcement work process also uses carbon fiber reinforced plastic formed by arranging carbon fiber, which is an example of reinforcing fiber, in one direction into a sheet-like fabric.

[0041] As described above, the entire reinforcing target outer surface area 5 of the concrete wall 1 including the flange contact part 1B where the connecting flange 30A of the short pipe 30 abuts from the perforation axis direction is firmly reinforced with a reinforcing sheet layer formed by attaching the reinforcing sheet 10. The flange contact part 1B of this reinforcing sheet layer is subjected to hole processing for bolting the connecting flange 30A of the short pipe 30 to the concrete wall 1. A part of the reinforcing sheet 10 is damaged by this hole processing. However, on the outer peripheral side of the flange contact part 1B, a second reinforcing sheet 11 for reinforcement against hole processing is attached by executing the first pattern overlay reinforcement work process, so that the concrete wall 1 can be reinforced and maintained in a strong state.

[0042] The first pattern overlay method in this embodiment is executed according to the following procedures (1) to (2). (1) As shown in Fig. 8, among the outer surface regions 5 to be reinforced where four layers of reinforcing sheet layers are formed, along the left attachment line L5 that vertically bisects the position P1 corresponding to the left end of the outer peripheral edge of the flange contact portion 1B or a position near it on the left side, and the right attachment line L6 that vertically bisects the position P2 corresponding to the right end of the outer peripheral edge of the flange contact portion 1B or a position near it on the right side, an impregnating adhesive resin that cures at room temperature is applied at least over the width of the second reinforcing sheet 11. On the application surface of this impregnating adhesive resin, the second reinforcing sheet 11 for vertical lapping is attached along the vertical direction. This process is repeated four times (a plurality of times) to form a four-layer structure of the second reinforcing sheet 11 for vertical lapping. In this embodiment, the bolt missing length La due to the mounting holes 16 of the anchor bolts 15 (see Fig. 12) located at the left end or the right end is set to 50 mm with a margin, the overlapping length Lb extending upward and downward from it is set to 200 mm, and the total length L is set to 450 mm.

[0043] (2) Among the outer surface regions 5 to be reinforced where four layers of reinforcing sheet layers are formed, along the upper attachment line L7 that horizontally bisects the position P3 corresponding to the upper end of the outer peripheral edge of the flange contact portion 1B or a position near it above, and the lower attachment line L8 that horizontally bisects the position P4 corresponding to the lower end of the outer peripheral edge of the flange contact portion 1B or a position near it below, an impregnating adhesive resin that cures at room temperature is applied at least over the width of the second reinforcing sheet 11. On the application surface of this impregnating adhesive resin, the second reinforcing sheet 11 for horizontal lapping is attached along the horizontal direction. This process is repeated four times (a plurality of times) to form a four-layer structure of the second reinforcing sheet 11 for horizontal lapping. In this embodiment, the bolt missing length La due to the mounting holes 16 of each pair of anchor bolts 15 located on the upper side or the lower side is set to 50 mm with a margin, the overlapping length Lb extending to the left and right from it is set to 200 mm, and the total length L is set to 700 mm.

[0044] [6] Second roughening operation process Of the surfaces of the vertically laminated second reinforcing sheet 11 laminated in a four-layer structure and the surface of the horizontally laminated second reinforcing sheet 11, a second roughening work step is performed in which an abrasive such as sand is blown onto a region larger than the flange contact portion 1B where the connecting flange 30A of the short pipe 30 abuts from the perforation axis direction to roughen (rough-grind) it. The roughening treatment in this second roughening work step increases the adhesion to the putty material to be executed in the subsequent smoothing work step of the flange contact portion 1B.

[0045] [7] Smoothing work step of the flange contact portion 1B As shown in FIGS. 9 and 10, in the reinforcing target outer surface region 5 where the first pattern lamination reinforcement work step has been completed, a smoothing work step is performed to smooth the flange contact portion 1B where the connecting flange 30A of the short pipe 30 abuts from the perforation axis direction among the reinforcing sheet layers formed by the reinforcing sheet 10 and the second reinforcing sheet 11. While firmly reinforcing the reinforcing target outer surface region 5 of the concrete wall 1 including the flange contact portion 1B with the reinforcing sheet 10 and the second reinforcing sheet 11, in the smoothing work step, the flange contact portion 1B where unevenness, gaps, etc. have occurred in the reinforcing sheet layer is smoothed, so that the joint surface between the flange contact portion 1B and the connecting flange 30A of the short pipe 30 can be easily configured in an appropriate surface contact state.

[0046] In the smoothing work step, as shown in FIG. 9(a), a putty filling range 18 is marked with a putty filling circular template 17 having an outer diameter set larger than the outer peripheral edge of the flange contact portion 1B at the center portion including the flange contact portion 1B of the reinforcing sheet layer. As shown in FIG. 9(b), a masking tape 19 is attached along the outer peripheral side of the marked circular putty filling range 18. A first layer of putty filling treatment is performed by applying a putty material to the putty filling range 18 surrounded by the masking tape 19, and a curing treatment is performed on the first layer of putty that has been putty filled. A second layer of putty filling treatment is performed by applying a putty material to the upper surface of the cured first layer of putty, and a curing treatment is performed on the second layer of putty that has been putty filled. Perform unevenness adjustment to correct the upper surface of the second-layer pate that has been subjected to health care treatment to a smooth surface. After confirming the unevenness, apply a finishing pate material to the upper surface of the second-layer pate. As a result, an annular smooth flange mounting surface 20 serving as the surface of the finishing pate can be formed in the pate filling range 18 including the flange contact portion 1B. The flange mounting surface 20 and the connecting flange 30A of the short pipe 30 are configured in a surface-contact state in which they are substantially evenly in surface contact from the perforation axis direction.

[0047] [8] Second pattern additional pasting reinforcement work process As the sheet pasting patterns in the additional pasting reinforcement work process, there are a first pattern shown in FIG. 8 and a second pattern shown in FIG. 11. Either one of the additional pasting reinforcement in the first pattern or the additional pasting reinforcement in the second pattern may be adopted, or the additional pasting reinforcement combining the first pattern and the second pattern may be adopted. In this embodiment, an embodiment in which the second pattern additional pasting reinforcement work process is executed after the first pattern additional pasting reinforcement work process is described, but in the first pattern additional pasting reinforcement work process, the second pattern additional pasting reinforcement work process may be executed. In the additional pasting reinforcement work process of the second pattern shown in FIG. 11, on the outer peripheral side of the flange contact portion 1B where the connecting flange 30A of the short pipe 30 abuts, among the reinforcing sheet layers of the outer surface region 5 to be reinforced where the smoothing work process has ended, a third reinforcing sheet 12 for reinforcement against hole processing for bolting the connecting flange 30A to the concrete wall 1 is pasted. The third reinforcing sheet 12 used in this additional pasting reinforcement work process of the second pattern also uses carbon fiber reinforced plastic in which carbon fiber, an example of a reinforcing fiber, is arranged in one direction to form a sheet-like fabric.

[0048] The additional pasting reinforcement work process of the second pattern in this embodiment executes the following steps (1) to (2). (1) Among the outer surface regions 5 to be reinforced where the reinforcing sheet layer is formed, along the upper right rising inclined line L9 and the lower right rising inclined line L10 that are in contact with or close to the outer peripheral edge of the circular flange mounting surface 20 formed in the pate filling range 18 at a rising inclination angle of approximately 45 degrees to the right, apply an impregnating adhesive resin that cures at room temperature with a width of at least that of the third reinforcing sheet 12. Affix the third reinforcing sheet 12 on the application surface of this impregnating adhesive resin to form an additional patch in the rising inclination direction to the right.

[0049] (2) Next, along the upper left rising inclined line L11 and the lower left rising inclined line L12 that are in contact with or close to the outer peripheral edge of the circular flange mounting surface 20 at a rising inclination angle of approximately 45 degrees to the left, apply an impregnating adhesive resin that cures at room temperature with a width of at least that of the third reinforcing sheet 12. Affix the third reinforcing sheet 12 on the application surface of this impregnating adhesive resin to form an additional patch in the rising inclination direction to the left. Repeat this process four times (multiple times) to form a four-layer structure of the third reinforcing sheet 12 that is an additional patch in the rising inclination direction to the right and the third reinforcing sheet 12 that is an additional patch in the rising inclination direction to the left. Note that the sheet attachment pattern in the additional patch reinforcement work process is not limited to the above-described first pattern and second pattern. For example, an annular pattern such as a circle, triangle, quadrilateral, pentagon, etc. may also be used.

[0050] [9] is the steel bar cutting and removing process in the suspension hole 6A As shown in FIG. 12, cut and remove the outer surface side steel bar 9 exposed at the bottom inside the suspension hole 6A with a cutting tool. At the time of cutting this outer surface side steel bar 9, since the concrete wall 1 has been reinforced to a strong state by performing the reinforcement work process, the first additional patch reinforcement work process, and the second additional patch reinforcement work process, it will not have an adverse effect on the concrete wall 1. Also, by previously cutting and removing the outer surface side steel bar 9 exposed at the bottom inside the suspension hole 6A before the drilling work process, the drilling load on the cutter 51 can be reduced.

[0051]

[10] Anchor bolt mounting work process As shown in Fig. 12, at the outer surface area 5 of the concrete wall 1 to be reinforced and on the annular smooth flange mounting surface 20 formed within the putty filling range 18, mark the drilling center positions of the mounting holes 16 for a plurality of (six in this embodiment) anchor bolts 15. Next, drill (core out) the marked drilling center positions with the core cutter of the drilling drill. Put an adhesive into the drilled mounting holes 16, and in this state, place the anchor bolts 15. Fix the anchor bolts 15 to the concrete wall 1 by curing and curing the adhesive.

[0052]

[11] Short pipe mounting operation process As shown in Fig. 13, attach an elastic sealing material (such as a rubber ring) 33 to the annular seal mounting groove (not shown) formed on the contact surface side of the connecting flange 30A at one end of the short pipe 30. Insert the anchor bolts 15 protruding from the flange mounting surface 20 of the concrete wall 1 into the respective bolt insertion holes (not shown) formed in the connecting flange 30A of the short pipe 30. By tightening the nuts 34 screwed onto the respective anchor bolts 15, fix the connecting flange 30A of the short pipe 30 to the flange mounting surface 20 of the concrete wall 1 in a watertight state.

[0053]

[12] Hydrostatic test process for short pipe As shown in Fig. 14, connect the connecting flange 35A at one end (upstream side) of the hydrostatic test short pipe 35 to the connecting flange 30B at the other end (downstream side) of the short pipe 30 in a watertight state. Connect a flange cover 38 equipped with a test water supply pipe 37 with a pressure gauge 36 to the connecting flange 35B at the other end (downstream side) of the hydrostatic test short pipe 35 in a watertight state. Next, inject pressure water at the set test water pressure into the short pipe 30 and the hydrostatic test short pipe 35, and check for any water leakage between the connecting flange 30A of the short pipe 30 and the flange mounting surface 20 of the concrete wall 1. After the hydrostatic test is completed, remove the hydrostatic test device such as the hydrostatic test short pipe 35 from the connecting flange 30B at the other end of the short pipe 30.

[0054]

[13] Installation operation process of the isolation valve 15, a connecting flange 40A at one end (upstream side) of a gate valve 40 is watertightly connected to a connecting flange 30B at the other end (downstream side) of the short pipe 30. A gate valve support 41 made of metal or concrete that supports the gate valve 40 on the ground is arranged between the bottom of a valve box 40C of the gate valve 40 and the upper surface of the base concrete 4. In this embodiment, the water pressure test is performed when the short pipe 30 is installed, but the water pressure test may be performed when the gate valve 40 is installed. In this case, a flange cover 38 with a water pressure gauge 36 is connected in a watertight manner to the connecting flange 40B on the other end side (downstream side) of the gate valve 40.

[0055]

[14] Support concrete construction process As shown in FIG. 15, a support concrete construction step is carried out to construct short pipe support concrete 31 that supports the short pipe 30 on the ground. In this supporting concrete construction process, the reinforcing sheet layer of the outer surface region 5 to be reinforced of the roughened concrete wall 1 is used as the front formwork surface. A rear formwork (not shown) is placed at a distance from the reinforcing sheet layer equivalent to the thickness of the supporting concrete 31 for short pipes. In addition, side formwork (not shown) is placed at positions corresponding to the left and right side surfaces of the supporting concrete 31 for short pipes. Steel bars are placed in the molding space surrounded by the reinforcing sheet layer and the formwork. Thereafter, concrete is poured into the molding space and cured to construct the supporting concrete 31.

[0056]

[15] Drilling work process As shown in Figures 16 to 18, after the supporting concrete 31 has been cured, a drilling operation step is carried out in which a cylindrical cutter (hole saw) 51 of a drilling machine 50 is used to drill a chipping hole 6A at a drilling-corresponding location 1A in the concrete wall 1, to form a through hole 6 for connecting to a pipeline for taking in the stored water. There have conventionally been various types of drilling machines 50, and any type of drilling machine 50 can be used.

[0057] In this embodiment, as shown in FIG. 16, a connecting flange 52A of a drilling work case 52 capable of accommodating a cutter 51 is connected in a watertight state to a connecting flange 40B on the other end side (downstream side) of a partition valve 40. The drilling work case 52 is provided with a drive support portion 55 that supports a drive shaft 53 of the cutter 51 so as to be movable in the feeding direction along the drilling axis and that has a drive motor 54 for the drive shaft 53. The drive support portion 55 moves along a feeding guide shaft 56 provided in the drilling work case 52 along the drilling axis direction.

[0058] As shown in FIG. 17, while rotating the drive shaft 53 of the cutter 51, it is fed into a drilling corresponding portion 1A of the concrete wall 1, and a through hole 6 is formed so as to be continuous with a suspension hole 6A in the concrete wall 1. When the through hole 6 is formed, as shown in FIG. 18, the cutter 51 at the through hole forming position is recovered into the drilling work case 52.

[0059]

[16] Drilling machine removal process As shown in FIG. 19, the valve body 40D of the partition valve 40 is closed, and the drilling machine 50 including the drilling work case 52 is removed from the connecting flange 40B on the other end side of the partition valve 40.

[0060] 〔Alternative embodiment〕 (1) In the above-described embodiment, carbon fiber is exemplified as the reinforcing fiber of the reinforcing sheet 10, but other reinforcing fibers such as aramid fiber, glass fiber, and PET fiber may be adopted.

[0061] (2) In the above-described embodiment, in the suspension work process, a suspension hole 6A having a depth at which a part of the reinforcing bar 9 arranged in the concrete wall 1 is exposed is formed at a drilling corresponding portion 1A on the outer surface 1a of the concrete wall 1, but this suspension work process may be omitted.

Explanation of reference numerals

[0062] 1 Structure (concrete wall) 1A Drilling corresponding portion 1B Flange contact portion 1a Outer surface 5 Reinforcement target outer surface area 6 Through-hole 8 Rebar (inner-side rebar) 9 Rebar (outer-side rebar) 10 Reinforcing sheet 11 Reinforcing sheet (second reinforcing sheet) 12 Reinforcing sheet (third reinforcing sheet) 30 Short pipe 30A Connecting flange 31 Support concrete (support concrete for short pipe) 50 Drilling machine 51 Cutter X Drilling axis

Claims

1. A method for drilling a concrete structure to form a through-hole with a cutter of a drilling machine, comprising: Before performing the drilling operation step by the drilling machine, a reinforcement operation step of attaching a reinforcing sheet provided with reinforcing fibers to a reinforcement target outer surface region on the outer peripheral side of the drilling equivalent portion on the outer surface of the structure is performed. The reinforcement target outer surface region to which the reinforcing sheet is attached in the reinforcement operation step does not include the drilling equivalent portion, and is a method for drilling a concrete structure including a flange contact portion where a connection flange of a short pipe into which the cutter of the drilling machine can be inserted abuts.

2. The amount of the reinforcing sheet used in the reinforcement operation step is set to an amount that satisfies the Young's modulus × cross-sectional area of the reinforcing sheet equivalent to the Young's modulus × cross-sectional area of the reinforcing bars that are located at the drilling equivalent portion and are cut and removed among the steel reinforcements in the structure. The method for drilling a concrete structure according to Claim 1.

3. A method for drilling a concrete structure to form a through-hole with a cutter of a drilling machine, comprising: Before performing the drilling operation step by the drilling machine, a reinforcement operation step of attaching a reinforcing sheet provided with reinforcing fibers to a reinforcement target outer surface region on the outer peripheral side of the drilling equivalent portion on the outer surface of the structure is performed. The method for drilling a concrete structure includes a peeling operation step of peeling the drilling equivalent portion of the structure from the outer surface until a part of the steel reinforcement in the structure is exposed, and the peeling operation step is performed before the reinforcement operation step.

4. A method for drilling a concrete structure to form a through-hole with a cutter of a drilling machine, comprising: Before performing the drilling operation step by the drilling machine, a reinforcement operation step of attaching a reinforcing sheet provided with reinforcing fibers to a reinforcement target outer surface region on the outer peripheral side of the drilling equivalent portion on the outer surface of the structure is performed. Among the reinforcing sheet layers formed by pasting the reinforcing sheet, a reinforcing work process of pasting a reinforcing sheet for reinforcement against hole processing for bolting the connecting flange to the structure is provided on the outer peripheral side of the flange contact portion where the connecting flange of the short pipe into which the cutter of the perforator can be inserted abuts. A method for drilling a concrete structure.

5. A method for drilling a concrete structure in which a through hole is formed by a cutter of a drilling machine in a concrete structure, Before performing the drilling operation step by the drilling machine, a reinforcing operation step of pasting a reinforcing sheet provided with reinforcing fibers is performed on the outer surface region to be reinforced on the outer peripheral side of the portion corresponding to the drilling on the outer surface of the structure, Among the reinforcing sheet layers formed by pasting the reinforcing sheet, a smoothing operation step of smoothing the flange contact portion where the connecting flange of the short pipe into which the cutter of the perforator can be inserted abuts is provided. A method for drilling a concrete structure.

6. A method for drilling a concrete structure in which a through hole is formed by a cutter of a drilling machine in a concrete structure, Before performing the drilling operation step by the drilling machine, a reinforcing operation step of pasting a reinforcing sheet provided with reinforcing fibers is performed on the outer surface region to be reinforced on the outer peripheral side of the portion corresponding to the drilling on the outer surface of the structure, In the reinforcing operation step, a plurality of layers are formed with a single layer of a reinforcing sheet layer pasted along at least two intersecting directions of the reinforcing sheet, and a first roughening operation step of roughening the outer surface of the reinforcing sheet layer located inside in the lamination direction is provided. A method for drilling a concrete structure.

7. A second roughening operation step of roughening the outer surface of the reinforcing sheet layer formed in the reinforcing operation step, and a support concrete construction step of constructing the support concrete for supporting the short pipe fixed to the flange contact portion of the structure in a state of being joined to the outer surface of the reinforcing sheet layer. The method for drilling a concrete structure according to claim 4 or 5.

8. The method for drilling a concrete structure according to claim 3, wherein a pretreatment work step of smoothing the outer surface region to be reinforced on the outer surface of the structure by primer treatment, base adjustment, etc. is performed between the hanging work step and the reinforcement work step.

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