Rehabilitation methods for rehabilitated pipes and existing pipes

Abstract

To provide a reform pipe which can secure strength of the reform pipe and be transported in an existing pipe, and to provide an existing pipe reforming method.SOLUTION: A second reform pipe 12 is a pipe for reforming an existing pipe 1 with which an existing branch pipe 2 is connected. The second reform pipe 12 includes a reform main pipe 15 and a branch pipe part 16. The branch pipe part 16 is branched from the reform main pipe 15 and formed having a diameter smaller than that of the reform main pipe 15. Further, an opening end 16c of the branch pipe part 16 is formed in an arc shape centered on a pipe axis 28 in a side view in which the branch pipe part 16 is viewed from a pipe axis direction of the reform main pipe 15.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a rehabilitation pipe and a method for rehabilitating an existing pipe.

Background Art

[0002] In the rehabilitation work of existing pipes in sewer and agricultural water fields, when the existing pipes are deteriorated, a method of rehabilitating the existing pipes by sequentially inserting a new rehabilitation pipe into the existing pipes (for example, the sheath pipe method) is known.

[0003] According to this type of rehabilitation method, as disclosed in Patent Document 1 for example, shafts (vertical holes) are provided upstream and downstream of the repair target portion of the existing pipe, and the rehabilitation pipe is sequentially lowered from one of the shafts into the existing pipe. Next, after lifting the rehabilitation pipe by the jack of the transport trolley installed in the shaft, the rehabilitation pipe is transported (carried) into the existing pipe using a battery car for pipe transportation or the like. At the transport destination, the insertion port of another rehabilitation pipe is connected to the receiving port of the rehabilitation pipe. By sequentially repeating this connection operation, a plurality of rehabilitation pipes are connected over the entire section between the starting shaft and the arrival shaft, and a plurality of rehabilitation pipes are constructed inside the existing pipe. Further, a backfill material such as mortar is filled in the gap between the existing pipe and the plurality of rehabilitation pipes to integrally fix the plurality of rehabilitation pipes inside the existing pipe.

[0004] Here, when an existing branch pipe (existing inflow pipe portion) connected to the rehabilitation pipe is provided in the existing pipe, a mounting hole is drilled in the rehabilitation pipe. After drilling the mounting hole, a connecting pipe is carried into the interior of the rehabilitation pipe. The carried-in connecting pipe is inserted from the interior of the rehabilitation pipe into the mounting hole and protruded to the outside. Further, the connecting pipe protruding to the outside of the rehabilitation pipe is connected to the existing branch pipe. Thereby, the existing branch pipe is communicated with the interior of the rehabilitation pipe through the connecting pipe. In this state, the gap between the mounting hole and the connecting pipe is filled with resin mortar (epoxy resin-based two-component bonding agent) to fix the connecting pipe.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2013-50203 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] In contrast, the conventional rehabilitation method involves inserting a connecting pipe into a mounting hole drilled in the rehabilitation pipe, and then connecting the inserted connecting pipe to the existing branch pipe. However, this method may affect the strength of the rehabilitation pipe when mounting holes are drilled into it.

[0007] One possible solution is to pre-connect a connecting pipe to the mounting hole of the rehabilitation pipe, thereby reinforcing the rehabilitation pipe with the connecting pipe. However, if a connecting pipe is pre-connected to the mounting hole of the rehabilitation pipe, the connecting pipe will protrude significantly outward from the outer wall of the rehabilitation pipe. As a result, when transporting the rehabilitation pipe into the pipeline, the connecting pipe may interfere with the existing pipe, making it difficult to transport the rehabilitation pipe to the connection point of the existing branch pipe.

[0008] The present invention has been made in view of the circumstances described above, and aims to provide a rehabilitated pipe and a method for rehabilitating an existing pipe that can ensure the strength of the rehabilitated pipe and can be transported within the existing pipe. [Means for solving the problem]

[0009] To solve the aforementioned problems, the present invention proposes the following means. "1" The rehabilitation pipe according to the present invention is a rehabilitation pipe for rehabilitating an existing pipe to which an existing branch pipe is connected, comprising a rehabilitation main pipe and a branch pipe section that branches off from the rehabilitation main pipe and has a smaller diameter than the rehabilitation main pipe, wherein in a side view of the branch pipe section as seen from the pipe axis direction of the rehabilitation main pipe, the open end of the branch pipe section is in the shape of an arc with respect to the pipe axis.

[0010] In the case of the rehabilitation pipe described above, a branch pipe section is provided in the rehabilitation main pipe, and the branch pipe section is branched off from the rehabilitation main pipe. Therefore, a connecting pipe can be inserted into the branch pipe section from inside the rehabilitation pipe, and the connecting pipe can be connected to the existing branch pipe. By providing a branch pipe section in the rehabilitation main pipe in this way, concerns about the strength of the rehabilitation pipe at the mounting hole, which were a concern with conventional technology, are resolved. In other words, by providing a branch pipe section in the rehabilitation main pipe, the rehabilitation main pipe can be reinforced by the branch pipe section, and the strength of the rehabilitation pipe can be ensured even when the diameter of the mounting hole is large, for example.

[0011] Furthermore, the open end of the branch pipe section is formed in an arc shape centered on the pipe axis of the rehabilitated main pipe. Therefore, the open end of the branch pipe section can be formed along the outer wall of the rehabilitated main pipe. This prevents the open end of the branch pipe section from protruding significantly from the outer wall of the rehabilitated main pipe, minimizing the amount of protrusion of the branch pipe section. Consequently, for example, even in the narrow interior of an existing pipe, the rehabilitated pipe can be transported to the connection point of the existing branch pipe (existing inflow pipe) without interfering with the existing pipe.

[0012] "2" In this embodiment, the diameter of the branch pipe section is 500 mm or more, and it may be the rehabilitation pipe described in "1".

[0013] Here, for example, if the diameter of the branch pipe section is 500 mm or more, the mounting hole in the rehabilitated main pipe into which the connecting pipe is inserted becomes larger. This increases the possibility of affecting the strength of the rehabilitated pipe. Therefore, the rehabilitated main pipe is equipped with a branch pipe section, into which the connecting pipe is inserted. This makes it possible to apply the rehabilitated pipe when the diameter of the branch pipe section is 500 mm or more, thereby expanding the applications of the rehabilitated pipe.

[0014] "3" In this embodiment, the rehabilitation main pipe and the branch pipe section may be the rehabilitation pipe described in "1" or "2", wherein the rehabilitation main pipe and the branch pipe section are made of fiber-reinforced plastic.

[0015] In this case, the strength of the rehabilitated main pipe and branch pipe sections can be increased by using fiber-reinforced plastic. This allows for even more favorable assurance of the strength of the rehabilitated pipe.

[0016] "4" In this embodiment, the rehabilitation main pipe and the branch pipe section are separate components and may be the rehabilitation pipe described in any of "1" to "3" above, bonded together with a sheet material.

[0017] In this case, the rehabilitated main pipe and the branch pipe section were constructed from separate components, and the rehabilitated main pipe and the branch pipe section were bonded together with a sheet material. Therefore, the mounting hole connecting the branch pipe section to the rehabilitated main pipe can be reinforced with the sheet material. Furthermore, the branch pipe section can be firmly fixed to the rehabilitated main pipe with the sheet material, and the rehabilitated main pipe and the branch pipe section can be integrated. This further enhances the strength of the rehabilitated pipe.

[0018] "5" In this embodiment, a guide portion is attached to the connection port of the existing branch pipe, and the rehabilitation pipe may be one of the pipes described in "1" to "4".

[0019] In this case, for example, the pipe can be easily connected to the connection port of an existing branch pipe using the guide section.

[0020] "6" The method for rehabilitating an existing pipe according to the present invention is a method for rehabilitating an existing pipe to which an existing branch pipe is connected using a rehabilitated pipe described in any of "1" to "5", comprising a transport step of transporting the rehabilitated pipe inside the existing pipe, and a connection step of inserting a connecting pipe into the branch pipe section from inside the rehabilitated pipe and connecting the connecting pipe to the existing branch pipe.

[0021] With the existing pipe rehabilitation method described above, the rehabilitation pipe has an open end at the branch section that is formed in an arc shape centered on the pipe axis of the main rehabilitation pipe. Therefore, the open end at the branch section can be formed along the outer wall of the main rehabilitation pipe. This prevents the open end at the branch section from protruding significantly from the outer wall of the main rehabilitation pipe, thereby minimizing the amount of protrusion of the branch section. Therefore, when transporting the rehabilitated pipe within the existing pipe during the transport process, for example, even within a narrow existing pipe, the rehabilitated pipe can be transported to the connection point of the existing branch pipe without the branch pipe interfering with the existing pipe.

[0022] In addition, a branch pipe section branches from the main rehabilitation pipe. Therefore, in the connection process, the connection pipe can be inserted into the branch pipe section from the inside of the rehabilitation pipe, and the connection pipe can be connected to the existing branch pipe. By providing the branch pipe section in the main rehabilitation pipe in this way, concerns about the strength of the rehabilitation pipe when the diameter of the mounting hole is large, which were a concern in the prior art, are eliminated. That is, by providing the branch pipe section in the main rehabilitation pipe, the main rehabilitation pipe can be reinforced by the branch pipe section, and the strength of the rehabilitation pipe can be ensured even when the diameter of the mounting hole is large.

[0023] In the "7" embodiment, it may be a method for rehabilitating an existing pipe of a rehabilitation pipe according to "6", wherein the rehabilitation pipe is rotated around the pipe axis during the conveying process or between the conveying process and the connecting process.

[0024] In this case, during the conveying process or between the conveying process and the connecting process, the rehabilitation pipe is rotated around the pipe axis. Therefore, when the rehabilitation pipe is conveyed to the connection position of the existing branch pipe, it is arranged at a position where the branch pipe section does not interfere with the existing pipe and conveyed to the connection position. After the rehabilitation pipe is conveyed to the connection position, the rehabilitation pipe is rotated around the pipe axis, and for example, the branch pipe section can be aligned with the existing branch pipe in the vertical direction (height direction). As a result, for example, even in a narrow existing pipe, the rehabilitation pipe can be conveyed to the connection position of the existing branch pipe and connected to the existing branch pipe without interfering the branch pipe section with the existing pipe.

[0025] In the "8" embodiment, it may be a method for rehabilitating an existing pipe according to "6" or "7", which includes a guide portion attaching step of attaching a guide portion to the connection port of the existing branch pipe before the connecting step.

[0026] In this case, for example, the pipe can be made easier to connect to the connection port of the existing branch pipe by the guide portion.

Advantages of the Invention

[0027] According to the present invention, the strength of the rehabilitation pipe can be ensured, and further, the rehabilitation pipe can be conveyed inside the existing pipe.

Brief Description of the Drawings

[0028] [Figure 1] This is an explanatory diagram showing one step of a method for rehabilitating an existing pipe according to a first embodiment of the present invention. [Figure 2] This is a plan view showing a state in which multiple rehabilitation pipes are arranged in a continuous manner in the existing pipe of the first embodiment. [Figure 3] This is a cross-sectional view showing the first rehabilitation pipe of the first embodiment laid inside the existing pipe. [Figure 4] This is a cross-sectional view showing the second rehabilitation pipe of the first embodiment laid inside the existing pipe. [Figure 5] This is an enlarged cross-sectional view of section V in Figure 4. [Figure 6] This is a cross-sectional view along the line VI-VI in Figure 5. [Figure 7] This is a side view from the inside of the second rehabilitation pipe, showing the state in which the connecting pipe inserted into the branch pipe section of the first embodiment is fixed. [Figure 8] This is a side view showing the second rehabilitation tube of the first embodiment. [Figure 9] This is a cross-sectional view taken along the line IX-IX in Figure 8. [Figure 10] This is a cross-sectional view illustrating the position of the branch pipe section when transporting the first rehabilitation pipe of the first embodiment. [Figure 11] This is a cross-sectional view showing the second rehabilitation pipe of the second embodiment of the present invention laid inside an existing pipe. [Figure 12] This is a perspective view of the plate-shaped member before processing into the guide portion of the second embodiment. [Figure 13] This is a perspective view showing an example of processing a plate-shaped member. [Figure 14] This is a perspective view showing an example of processing a plate-shaped member. [Figure 15] This is a side view showing the second rehabilitation tube of the second embodiment. [Figure 16] Figure 15 is a cross-sectional view fractured along the line XV-XV. [Figure 17] This is an enlarged cross-sectional view of the main part of the first modified example of the second embodiment according to the present invention. [Figure 18] This is an enlarged cross-sectional view of the main part of a second modified example of the second embodiment according to the present invention. [Figure 19] This is an enlarged cross-sectional view of the main part of a third modified example of the second embodiment according to the present invention. [Modes for carrying out the invention]

[0029] The following describes a rehabilitation pipe and a rehabilitation method for an existing pipe according to one embodiment of the present invention, with reference to the drawings. [First Embodiment] Figure 1 is an explanatory diagram showing one step of the rehabilitation method for existing pipes according to the first embodiment of the present invention. Figure 2 is a plan view showing a state in which multiple rehabilitation pipes are arranged in a continuous manner on the existing pipe according to the first embodiment. As shown in Figures 1 and 2, before explaining the method for rehabilitating the existing pipe 1, we will briefly describe the rehabilitation pipe 10 used in the rehabilitation method for the existing pipe. The rehabilitation pipe 10 includes, for example, a first rehabilitation pipe 11 of a standard shape, a second rehabilitation pipe 12 equipped with a branch pipe section 16 (described later), and a third rehabilitation pipe (adjustment pipe) 13 for adjustment.

[0030] The first rehabilitation tube 11 is, for example, a straight tube (cylindrical shape) made of fiber-reinforced plastic having a constant inner and outer diameter, and has a receiving end 11a and a spigot end 11b. The receiving end 11a is provided at one end of the first rehabilitation tube 11 and has an inner diameter corresponding to the outer diameter of the first rehabilitation tube 11. The spigot end 11b is formed at the other end of the first rehabilitation tube 11 in a tapered shape that gradually becomes thinner outward.

[0031] As will be described later, the first rehabilitation pipe 11 is transported sequentially in the direction of arrow A within the existing pipe 1 and positioned in front of and behind the pipe axis. The front of the pipe axis is the direction of transport of the first rehabilitation pipe 11 (direction of arrow A), and the rear of the pipe axis is the direction opposite to the direction of transport of the first rehabilitation pipe 11. When the first rehabilitation pipe 11 is transported continuously within the existing pipe 1, adjacent first rehabilitation pipes 11 are connected by inserting the receiving port 11a of one first rehabilitation pipe 11 into the insertion port 11b of the other first rehabilitation pipe 11. Hereinafter, the direction of the pipe axis of the first rehabilitation pipe 11, the second rehabilitation pipe 12, and the third rehabilitation pipe 13 may also be referred to as the "pipe axis direction."

[0032] The first rehabilitation pipe 11 is provided with a watertight rubber seal (not shown) on the inner surface of the receiving port 11a or the outer surface of the insertion port 11b. This makes it possible to seal the receiving port 11a and the insertion port 11b of another first rehabilitation pipe 11 by inserting the insertion port 11b of the first rehabilitation pipe 11 into the receiving port 11a of the first rehabilitation pipe 11 and connecting them via the watertight rubber seal.

[0033] The second rehabilitation pipe 12 is the first rehabilitation pipe 11 with a branch pipe section 16, and its other configurations are the same as the first rehabilitation pipe 11. The branch pipe section 16 of the second rehabilitation pipe 12 is positioned at the connection point of the existing branch pipe (existing inlet pipe) 2. The branch pipe section 16 protrudes from the outer wall of the rehabilitation main pipe 15 of the second rehabilitation pipe 12. The branch pipe section 16 is formed in a cylindrical shape and communicates with the inside of the second rehabilitation pipe 12. With the second rehabilitation pipe 12 positioned at the connection point, the connecting pipe 5 is inserted into the branch pipe section 16 from inside the second rehabilitation pipe 12. The connecting pipe 5 is then made to protrude from the branch pipe section 16 and connected (inserted) into the existing branch pipe 2. The existing branch pipe 2 is located in the existing pipe 1. The second rehabilitation pipe 12 will be explained in more detail later.

[0034] The third rehabilitation pipe 13 is formed with a longer ferrule length than the first rehabilitation pipe 11, and its other shape is the same as the first rehabilitation pipe 11. The third rehabilitation pipe 13 is interposed between the first rehabilitation pipe 11 and the second rehabilitation pipe 12, for example in the pipe axis direction, so that the branch pipe section 16 of the second rehabilitation pipe 12 is positioned at the connection point. In other words, the third rehabilitation pipe 13 is an adjustment pipe that adjusts the position of the branch pipe section 16 of the second rehabilitation pipe 12 so that it is positioned at the connection point. For example, the length of the third rehabilitation pipe 13 (for example, the length of the ferrule 13b) may be adjusted by cutting the third rehabilitation pipe 13 outside the existing pipe 1. Alternatively, the third rehabilitation pipe 13 may be omitted, and the rehabilitation pipe 10 may be formed by two types of pipes, the first rehabilitation pipe 11 and the second rehabilitation pipe 12.

[0035] Next, the method for rehabilitating an existing pipe according to the embodiment will be described with reference to Figures 1 to 7. An existing branch pipe 2 is connected to the existing pipe 1 to be rehabilitated. The existing branch pipe 2 is connected to the branch pipe section 16 of the second rehabilitated pipe 12 during the rehabilitation of the existing pipe 1. First, at the repair site of the existing pipe 1, for example, a shaft (vertical hole) M is excavated at the end of the construction section. Here, the existing pipe 1 has a rectangular opening 7 (see Figure 6) where the existing branch pipe 2 is connected. In this state, as a preliminary step before transporting the first rehabilitation pipe 11, the second rehabilitation pipe 12, and the third rehabilitation pipe 13 into the existing pipe 1, an insertion process is performed to form a recess 8 (see Figure 6) by chipping away at both side walls and the bottom of the opening 7.

[0036] Next, the first rehabilitation pipe 11 is brought into the shaft M and transported from the shaft M toward the construction section of the existing pipe 1. Specifically, the first rehabilitation pipe 11 is lowered into the shaft M in order so that the opening 11b faces the direction of transport. Then, the first rehabilitation pipe 11 is placed on a transport trolley (not shown). The transport trolley is capable of transporting the rehabilitation pipes 10 (i.e., the first rehabilitation pipe 11, the second rehabilitation pipe 12, and the third rehabilitation pipe 13) while supporting them, and is also capable of rotating the rehabilitation pipes 10 around their axis. A battery-powered cart (not shown) is attached to the transport trolley. The battery-powered cart and the transport trolley are used to transport the first rehabilitation pipe 11 to the construction section within the existing pipe 1.

[0037] Figure 3 is a cross-sectional view showing the first rehabilitation pipe of the first embodiment laid inside the existing pipe. As shown in Figure 3, a base (not shown) is installed between the first rehabilitated pipe 11 after transport and the bottom 1a of the existing pipe 1. In addition, an anti-float material (not shown) is placed on the outer surface of the approximately upper half of the first rehabilitated pipe 11, including the top 11c (see also Figure 1). For example, an arc-shaped plate material curved to an inner diameter corresponding to the outer diameter of the receiving opening 11a of the first rehabilitated pipe 11 can be used as the anti-float material. This allows the first rehabilitated pipe 11 to be supported and fixed so that its axis approximately coincides with the axis of the existing pipe 1.

[0038] Returning to Figures 1 and 2, after supporting and fixing the leading first rehabilitation pipe 11 at the designated position in the construction section, the battery car and transport trolley are retrieved into the shaft M. Next, in the shaft M, the first rehabilitation pipes 11 are lowered in sequence and supported by the transport trolley. After that, the first rehabilitation pipes 11 are transported to the construction section using the battery car and transport trolley, and the insertion opening 11b of the first rehabilitation pipe 11 is inserted into the receiving opening 11a of the leading first rehabilitation pipe 11 to connect them. After connecting the subsequent first rehabilitation pipe 11 to the leading first rehabilitation pipe 11, a base is installed on the pipe bottom 1a of the existing pipe 1 corresponding to the subsequent first rehabilitation pipe 11. Furthermore, an anti-float material is placed on the outer surface of the first rehabilitation pipe 11, and the first rehabilitation pipe 11 is supported and fixed so that its axis substantially coincides with the axis of the existing pipe 1.

[0039] Similarly, in the shaft M, the number of first rehabilitation pipes 11 required for the rehabilitation of the existing pipe 1 are lowered and laid in the construction section. After this, as will be described later, the second rehabilitation pipe 12 is installed corresponding to the existing branch pipe 2. If, at this point, the last of the multiple first rehabilitation pipes 11 is installed, the position of the second rehabilitation pipe 12 in the pipe axis direction will be misaligned with the existing branch pipe 2. In such cases, for example, a third rehabilitation pipe 13 can be used instead of the last first rehabilitation pipe 11. In this embodiment, it is assumed that a third rehabilitation pipe 13 is used, but as mentioned above, the third rehabilitation pipe 13 is not required.

[0040] Next, the steps (first step, second step (transportation step), and third step (connection step)) for implementing the rehabilitation method of the existing pipe 1 to which the existing branch pipe 2 is connected using the second rehabilitation pipe 12 will be explained in detail with reference to Figures 1, 2, 4 to 7. First, as shown in Figures 1 and 2, in the first step after laying the first rehabilitation pipe 11 and the third rehabilitation pipe 13 in the construction section, the second rehabilitation pipe 12 is lowered into the shaft M with its opening 12b facing the transport direction. This completes the first step.

[0041] Next, in the second step, the second rehabilitation pipe 12 that has been brought in is transported from the shaft M into the interior of the existing pipe 1 using a battery cart and a transport trolley to the laying position in the construction section inside the existing pipe 1. The transport trolley is, for example, a trolley that can transport the second rehabilitation pipe 12 while supporting it, and can also rotate the second rehabilitation pipe 12 around its axis. Therefore, after transporting the second rehabilitation pipe 12 to the laying position, in the rotation step, the second rehabilitation pipe 12 can be rotated around its axis to align the branch pipe section 16 (described later) vertically (height direction) with respect to the connection position of the existing branch pipe 2. The reason for rotating the second rehabilitation pipe 12 will be explained in detail later.

[0042] In this state, the spigot 12b of the second rehabilitation pipe 12 is inserted into the receptacle 13a of the third rehabilitation pipe 13 and connected. The third rehabilitation pipe 13 is an adjustment pipe that adjusts the position of the branch pipe section 16 of the second rehabilitation pipe 12 so that it is positioned to match the connection position. Therefore, by inserting the spigot 12b of the second rehabilitation pipe 12 into the receptacle 13a of the third rehabilitation pipe 13 and connecting the second rehabilitation pipe 12 to the third rehabilitation pipe 13, the branch pipe section 16 of the second rehabilitation pipe 12 is aligned in the pipe axis direction with respect to the connection position of the existing branch pipe 2. This completes the second step.

[0043] Next, in the third step, an example of connecting the branch pipe section 16 of the second rehabilitation pipe 12 to the existing branch pipe 2 will be explained based on Figures 2, 4 to 7. Figure 4 is a cross-sectional view showing the second rehabilitation pipe of the first embodiment laid inside the existing pipe. Figure 5 is an enlarged cross-sectional view of section V in Figure 4.

[0044] As shown in Figures 4 and 5, in the third step, the branch pipe section 16 of the second rehabilitation pipe 12 is aligned with the connection position of the existing branch pipe 2 in the pipe axis direction and the vertical direction (height direction). In this state, an anti-float material (not shown) is placed on the outer surface of the approximately upper half of the second rehabilitation pipe 12, including the pipe top 12c. This supports the second rehabilitation pipe 12 so that its axis approximately coincides with the axis of the existing pipe 1, and the second rehabilitation pipe 12 can be fixed in a state in which floating of the second rehabilitation pipe 12 is prevented. In this state, the connecting pipe 5 is inserted from inside the second rehabilitation pipe 12 into the branch pipe section 16. The inserted connecting pipe 5 is then made to protrude from the branch pipe section 16 and inserted into the existing branch pipe 2 to connect them. For the connecting pipe 5, for example, a pipe made of fiber-reinforced plastic or a pipe made of polyvinyl chloride can be used.

[0045] Figure 6 is a cross-sectional view along the line VI-VI in Figure 5. As shown in Figures 5 and 6, a rectangular opening 7 is formed in the existing pipe 1 at the location where the existing branch pipe 2 is connected. As mentioned above, in the pre-process of transporting the first rehabilitation pipe 11, the second rehabilitation pipe 12, and the third rehabilitation pipe 13 into the existing pipe 1, an insertion process is performed to form a recess 8 by, for example, chipping away at both side walls and the bottom of the opening 7. By forming a recess 8 in the opening 7, one end 5a of the connecting pipe 5 can be inserted into the opening 7. By inserting one end 5a of the connecting pipe 5 into the opening 7, the connecting pipe 5 and the existing branch pipe 2 are aligned. In this state, a piece of lumber or the like is driven into the gap between the connecting pipe 5 and the branch pipe section 16 to temporarily fix the connecting pipe 5 coaxially with the existing branch pipe 2.

[0046] With the connecting pipe 5 temporarily fixed coaxially to the existing branch pipe 2, resin mortar (epoxy resin-based two-component adhesive) 22 is filled into the gap between one end 5a of the connecting pipe 5 and the opening 7. As a result, the gap between one end 5a of the connecting pipe 5 and the opening 7 is filled, and the connecting pipe 5 is integrated with the existing pipe 1. In this way, the connecting pipe 5 is fixed in a state of coaxial communication with the existing branch pipe 2.

[0047] Figure 7 is a side view from inside the second rehabilitation pipe, showing the state in which the connecting pipe inserted into the branch pipe section of the first embodiment is fixed. As shown in Figures 5 and 7, the excess length of the connecting pipe 5 protruding into the inside of the second rehabilitation pipe 12 is cut off. It is preferable to cut the connecting pipe 5 in a curved shape along the curvature of the inner surface of the second rehabilitation pipe 12. After cutting off the excess length of the connecting pipe 5, while removing lumber or the like from the gap between the connecting pipe 5 and the branch pipe section 16, resin mortar (epoxy resin two-component adhesive) 24 is filled into the gap between the other end 5b of the connecting pipe 5 and the branch pipe section 16 (specifically, the second FRP sheet 18 described later). Thus, the gap between the other end 5b of the connecting pipe 5 and the branch pipe section 16 is filled with resin mortar 24, and the connecting pipe 5 is integrated with the branch pipe section 16 while connected. In this state, the second rehabilitation pipe 12 is connected to the existing branch pipe 2 via the connecting pipe 5. That is, water flowing from the existing branch pipe 2 can be guided to the second rehabilitation pipe 12 via the connecting pipe 5. This completes the rehabilitation of the existing pipe 1 using the second rehabilitation pipe 12 in the third step.

[0048] The rehabilitation method for existing pipes described above is repeated sequentially to transport the second rehabilitation pipe to each connection point and connect it to the existing branch pipe. In the process after connecting multiple second rehabilitation pipes to their respective existing branch pipes, partition walls are installed at predetermined distances to partition multiple rehabilitation pipes 10 (i.e., the first rehabilitation pipe 11, the second rehabilitation pipe 12, and the third rehabilitation pipe 13) and the existing pipe 1 in the construction section. Backfill material is poured into the gap between the inner surface of the partitioned existing pipe 1 and the outer surface of the rehabilitation pipe 10, for example, by utilizing the grout holes formed in the rehabilitation pipe 10. For the backfill material, for example, air mortar can be used. The backfill material is repeatedly filled in at regular intervals between the rehabilitated pipe 10 and the existing pipe 1, and the backfill material is sequentially poured over the entire construction section. In this way, the rehabilitated pipe 10 can be integrally fixed to the existing pipe 1. This completes the rehabilitation process of the existing pipe 1.

[0049] When the backfill material is poured, the anti-float material attached to each rehabilitation pipe 10 maintains the gap between the existing pipe 1 and the rehabilitation pipe 10, preventing the rehabilitation pipe 10 from floating up. This allows the backfill material to be poured smoothly.

[0050] Next, the second rehabilitation pipe 12 according to the first embodiment will be described with reference to Figures 5, 8, and 9. Figure 8 is a side view showing the second rehabilitation pipe of the first embodiment. Figure 9 is a cross-sectional view broken along the line IX-IX in Figure 8. As shown in Figures 5, 8, and 9, the second rehabilitation pipe 12 comprises a rehabilitation main pipe 15, a branch pipe section 16, a first FRP sheet (FRP sheet, sheet material) 17, and a second FRP sheet (FRP sheet, sheet material) 18. The rehabilitation main pipe 15 is formed by opening (perforating) a mounting hole 26 in the first rehabilitation pipe 11, and its other shape is formed in the same way as the first rehabilitation pipe 11. That is, the rehabilitation main pipe 15 is, for example, a straight pipe (cylindrical shape) made of fiber-reinforced plastic with a certain inner and outer diameter. The rehabilitation main pipe 15 has a receiving opening 12a, a spigot opening 12b, and a mounting hole 26.

[0051] The receiving port 12a is provided at one end of the rehabilitation main pipe 15 and has an inner diameter corresponding to the outer diameter of the second rehabilitation pipe 12. The spigot 12b is located at the other end of the rehabilitation main pipe 15 and has been ground (thinned) over a certain width around its entire outer circumference. The rehabilitation main pipe 15 (i.e., the second rehabilitation pipe 12) is transported into the existing pipe 1 and connected, for example, by inserting the spigot 12b into the receiving port 13a (see Figures 1 and 2) of the adjacent third rehabilitation pipe 13 in the pipe axis direction (or the receiving port 11a of the first rehabilitation pipe 11 if there is no third rehabilitation pipe 13). The rehabilitation main pipe 15 is provided with a watertight rubber seal (not shown) on the inner surface of the receiving port 12a or the outer surface of the spigot 12b. As a result, for example, when the spigot 12b of the rehabilitation main pipe 15 is inserted into the receiving port 13a of the third rehabilitation pipe 13 (or the receiving port 11a of the first rehabilitation pipe 11) and connected, the spigot 12b and the receiving port 13a are sealed via the watertight rubber seal.

[0052] Mounting holes 26 are provided in the outer circumferential wall of the rehabilitation main pipe 15. The mounting holes 26 are circular in shape, centered at the center in the direction of the pipe axis and eccentrically offset downward by a distance H1 relative to the pipe axis 28, when viewed from the side of the rehabilitation main pipe 15 (as shown in Figure 8). The diameter of the mounting holes 26 is set to 500 mm or more when viewed from the side of the rehabilitation main pipe 15. The branch pipe section 16 is connected to the periphery of the mounting holes 26 (i.e., the outer wall of the rehabilitation main pipe 15).

[0053] The branch pipe section 16 is formed in a cylindrical shape coaxially with the mounting hole 26, centered at the center in the direction of the pipe axis and eccentrically offset downward by a distance H1 relative to the pipe axis 28, when viewed from the side of the rehabilitation main pipe 15. The base end of the branch pipe section 16 is connected to the periphery of the mounting hole 26 on the outer wall of the rehabilitation main pipe 15. In other words, the branch pipe section 16 branches outward from the rehabilitation main pipe 15. The branch pipe section 16 is a pipe made of fiber-reinforced plastic, just like the rehabilitation main pipe 15. By making the rehabilitation main pipe 15 and the branch pipe section 16 from fiber-reinforced plastic, the strength of the rehabilitation main pipe 15 and the branch pipe section 16 can be increased.

[0054] Furthermore, in a side view of the rehabilitated main pipe 15, the inner circumferential wall 16b of the branch pipe section 16 is formed flush with the mounting hole 26. In addition, the branch pipe section 16 is formed with a diameter (inner diameter) of 500 mm or more, and with a smaller diameter than the rehabilitated main pipe 15. Therefore, the existing branch pipe 2 to which the branch pipe section 16 connects is also formed with a diameter of 500 mm or more. In the first embodiment, as an example, the main rehabilitated pipe 15 is formed with a diameter of 1650 mm, and the branch pipe section 16 is formed with a diameter of 1000 mm. The diameters of the main rehabilitated pipe 15 and the branch pipe section 16 can be arbitrarily selected.

[0055] In addition, in a side view of the branch pipe section 16 as seen from the pipe axis direction of the rehabilitation main pipe 15 (side view shown in Figure 9), the open end 16c of the branch pipe section 16 is formed in an arc shape centered on the pipe axis 28. Therefore, the open end 16c of the branch pipe section 16 can be formed along the outer circumferential wall of the rehabilitation main pipe 15. This prevents the open end 16c of the branch pipe section 16 from protruding significantly from the outer circumferential wall of the rehabilitation main pipe 15. The reason why the open end 16c of the branch pipe section 16 is formed in an arc shape to prevent it from protruding significantly from the outer wall of the rehabilitated main pipe 15 will be explained in detail later.

[0056] A first FRP sheet 17 is bonded with resin (not shown) to the outer circumferential wall of the branch pipe section 16 and the outer circumferential wall of the rehabilitated main pipe 15 around the mounting hole 26. The first FRP sheet 17 is a sheet made of fiber-reinforced plastics. In addition, a second FRP sheet 18 is bonded with resin (not shown) to the inner circumferential wall of the branch pipe section 16 and the inner circumferential wall of the rehabilitated main pipe 15 around the mounting hole 26. The second FRP sheet 18 is a sheet made of fiber-reinforced plastics. In other words, the rehabilitated main pipe 15 and the branch pipe section 16, which are separate components, are integrally bonded together with the first FRP sheet 17 and the second FRP sheet 18.

[0057] Here, the reason why the open end 16c of the branch pipe section 16 is formed in an arc shape to prevent it from protruding significantly from the outer wall of the rehabilitated main pipe 15 will be explained based on Figures 4, 9, and 10. As shown in Figures 4 and 9, when the branch pipe section 16 of the second rehabilitation pipe 12 is connected to the existing branch pipe 2 of the existing pipe 1, the branch pipe section 16 is positioned below the second rehabilitation pipe 12. Therefore, when transporting the second rehabilitation pipe 12, it is conceivable that, for example, the branch pipe section 16 may interfere with the bottom 1a of the existing pipe 1. To address this, the second rehabilitation pipe 12 is rotated around its axis during the rotation process in the second process.

[0058] Figure 10 is a cross-sectional view illustrating the position of the branch pipe section when transporting the first rehabilitation pipe of the first embodiment. As shown in Figures 4 and 10, when the second rehabilitation pipe 12 is rotated around its axis in the direction of arrow B shown in Figure 4, the branch pipe section 16 moves upward. This allows the branch pipe section 16 to be moved upward away from the bottom 1a of the existing pipe 1 and to face the side wall 1b of the existing pipe 1. The side wall 1b of the existing pipe 1 is positioned at a relatively large distance from the outer wall of the rehabilitation main pipe 15. Therefore, by positioning the branch pipe section 16 to face the side wall 1b of the existing pipe 1, it is possible to prevent the branch pipe section 16 from interfering with the existing pipe 1 when transporting the second rehabilitation pipe 12 to the connection position of the existing branch pipe 2.

[0059] Furthermore, after transporting the second rehabilitation pipe 12 to the connection position of the existing branch pipe 2, rotating the second rehabilitation pipe 12 around its axis in the direction of arrow C shown in Figure 10 causes the branch pipe section 16 to move downward. This allows the branch pipe section 16 of the second rehabilitation pipe 12 to be aligned vertically with respect to the existing branch pipe 2. Therefore, for example, when regenerating a narrow existing pipe 1, the second rehabilitated pipe 12 can be transported to the connection point of the existing branch pipe 2 without the branch pipe section 16 interfering with the existing pipe 1. Furthermore, after transporting the second rehabilitation pipe 12 to the connection position of the existing branch pipe 2, the branch pipe section 16 can be aligned vertically with respect to the existing branch pipe 2, allowing the connecting pipe 5 inserted into the branch pipe section 16 to be inserted into the existing branch pipe 2 and connected.

[0060] As described above, according to the second rehabilitation pipe 12 of the first embodiment, as shown in Figures 5, 8, and 9, the rehabilitation main pipe 15 is provided with a branch pipe section 16, and the branch pipe section 16 is branched from the rehabilitation main pipe 15. Therefore, the connecting pipe 5 can be inserted into the branch pipe section 16 from inside the second rehabilitation pipe 12, and the connecting pipe 5 can be inserted into the existing branch pipe 2 for connection. In this way, by providing the rehabilitation main pipe 15 with a branch pipe section 16, the concerns regarding the strength of the second rehabilitation pipe 12 when the diameter of the mounting hole 26 is large, which were a concern in the prior art, are resolved. In other words, by providing the rehabilitation main pipe 15 with a branch pipe section 16, the rehabilitation main pipe 15 can be reinforced by the branch pipe section 16, and the strength of the second rehabilitation pipe 12 can be ensured even when the diameter of the mounting hole 26 is large.

[0061] Furthermore, the open end 16c of the branch pipe section 16 is formed in an arc shape centered on the pipe axis 28 of the rehabilitated main pipe 15. Therefore, the open end 16c of the branch pipe section 16 can be formed along the outer circumferential wall of the rehabilitated main pipe 15. This prevents the open end 16c of the branch pipe section 16 from protruding significantly from the outer circumferential wall of the rehabilitated main pipe 15, thereby minimizing the amount of protrusion of the branch pipe section 16. Consequently, for example, even inside a narrow existing pipe 1, the second rehabilitated pipe 12 can be transported to the connection point of the existing branch pipe 2 without the branch pipe section 16 interfering with the existing pipe 1.

[0062] Here, for example, if the diameter of the branch pipe section 16 is 500 mm or more, the mounting hole 26 of the rehabilitation main pipe 15 into which the connecting pipe 5 is inserted becomes larger. This may affect the strength of the rehabilitation main pipe 15 (i.e., the second rehabilitation pipe 12). Therefore, the branch pipe section 16 is provided in the mounting hole 26 of the rehabilitation main pipe 15, and the connecting pipe 5 is inserted into the mounting hole 26 and the branch pipe section 16. This makes it possible to apply the second rehabilitation pipe 12 even when the diameter of the branch pipe section 16 is 500 mm or more, thereby expanding the applications of the second rehabilitation pipe 12.

[0063] Furthermore, by making the rehabilitated main pipe 15 and the branch pipe section 16 from fiber-reinforced plastic, the strength of the rehabilitated main pipe 15 and the branch pipe section 16 can be increased. This makes it possible to more effectively ensure the strength of the second rehabilitated pipe 12.

[0064] Furthermore, the rehabilitated main pipe 15 and the branch pipe section 16 were constructed from separate components, and the rehabilitated main pipe 15 and the branch pipe section 16 were bonded together with a first FRP sheet 17 and a second FRP sheet 18. As a result, the mounting hole 26 connecting the branch pipe section 16 to the rehabilitated main pipe 15 can be reinforced with the first FRP sheet 17 and the second FRP sheet 18. In addition, the branch pipe section 16 can be firmly fixed to the rehabilitated main pipe 15 with the first FRP sheet 17 and the second FRP sheet 18, and the rehabilitated main pipe 15 and the branch pipe section 16 can be integrated. This further enhances the strength of the second rehabilitated pipe.

[0065] Furthermore, according to the rehabilitation method for existing pipes of the first embodiment, as shown in Figures 4, 5, and 10, the branch pipe section 16 of the second rehabilitation pipe 12 is formed so that its open end 16c is arc-shaped and does not protrude significantly from the outer wall of the rehabilitation main pipe 15. Therefore, the amount of protrusion of the branch pipe section 16 from the outer wall of the rehabilitation main pipe 15 can be minimized. As a result, when transporting the second rehabilitation pipe 12 inside the existing pipe 1 in the second process, the second rehabilitation pipe 12 can be transported to the connection point of the existing branch pipe 2 without interfering with the existing pipe 1, even inside the narrow existing pipe 1, for example.

[0066] Furthermore, the second rehabilitation pipe 12 has a branch pipe section 16 that branches off from the main rehabilitation pipe 15. Therefore, in the third step, the connecting pipe 5 can be inserted from inside the second rehabilitation pipe 12 into the branch pipe section 16, and the connecting pipe 5 can be inserted into the existing branch pipe 2 for connection. In this way, by providing the branch pipe section 16 to the second rehabilitation pipe 12, the concern regarding the strength of the second rehabilitation pipe 12 when the diameter of the mounting hole 26 is large, which was a concern in the conventional technology, is resolved. In other words, by providing the branch pipe section 16 to the main rehabilitation pipe 15, the main rehabilitation pipe 15 can be reinforced by the branch pipe section 16, and the strength of the second rehabilitation pipe 12 can be ensured even when the diameter of the mounting hole 26 is large.

[0067] In addition, during the rotation process in the second step, the second rehabilitation pipe 12 is rotated around its axis to move the branch pipe section 16 upward. As a result, the branch pipe section 16 can be moved away from the bottom 1a of the existing pipe 1 and positioned opposite the side wall 1b of the existing pipe 1. This prevents the branch pipe section 16 from interfering with the bottom 1a of the existing pipe 1 when transporting the first rehabilitation pipe 11 to the connection point of the existing branch pipe 2 in a narrow existing pipe, for example.

[0068] [Second Embodiment] Next, the rehabilitation method for the second rehabilitation pipe 62 and the existing pipe in the second embodiment will be described with reference to Figures 11 to 19. In the rehabilitation method for the second rehabilitation pipe 62 and the existing pipe in the second embodiment, the same or similar components as in the first embodiment are denoted by the same reference numerals and detailed explanations are omitted. The rehabilitation method for existing pipes in the second embodiment differs from the first embodiment mainly in that the connecting pipe 5 is connected to the existing branch pipe 2 using the guide section 50; the other rehabilitation methods are the same as in the first embodiment.

[0069] Figure 11 is a cross-sectional view showing the second rehabilitation pipe of the second embodiment of the present invention laid inside an existing pipe. As shown in Figure 11, the method for rehabilitating an existing pipe in the second embodiment involves fixing (installing) a guide section (guide plate) 50 to the connection port 2a of the existing branch pipe 2 using anchor bolts 51 on the pipe side wall 1b of the existing pipe 1. That is, the method for rehabilitating an existing pipe includes a guide section installation step of attaching the guide section 50 to the connection port 2a of the existing branch pipe 2. The guide section 50 is attached to the connection port 2a of the existing branch pipe 2. The guide section installation step is performed before the third step. The guide section (guide plate) 50 has an opening 57 that is located coaxially with the connection port 2a.

[0070] Here, we will explain the guide section 50 in detail. As shown in Figure 12, the guide portion 50 is a plate-like member with a thickness of 10 mm to 50 mm. Note that Figure 12 shows the plate-like member 50A before it is processed into the guide portion 50. For example, the guide portion 50 has a rectangular shape when viewed in the thickness direction. The guide portion 50 has an opening 57 that has a circular shape when viewed in the thickness direction. The opening 57 penetrates the guide portion 50 in the thickness direction. The width and length of the plate-shaped member 50A are not particularly limited, and it is sufficient if it is large enough to be transported to the construction site. This is because the plate-shaped member 50A can be cut to size to form the guide section 50. For example, the plate-shaped member 50A may have a width of 600 mm and a length of 1200 mm.

[0071] The material of the guide portion 50 (plate-shaped member 50A) may be any of the following: wood, concrete, thermoplastic resin, thermosetting resin, etc., and is not particularly limited. From the viewpoint of processability and workability at the construction site, it is more preferable that the material of the guide portion 50 be a fiber-reinforced composite material. The fiber-reinforced composite material is, for example, a cured product of glass long fibers and a rigid urethane resin composition. This cured product may contain foaming agents, additives, etc.

[0072] In order to attach the guide section 50 to the connection port 2a of the existing branch pipe 2, the following processing is performed to match the diameter (nominal diameter) of the connection port 2a of the existing branch pipe 2.

[0073] [Table 1]

[0074] For example, if the diameter of the connection port 2a of the existing branch pipe 2 is 75A, then the outer diameter a (mm) of the connection pipe 5 is 89mm. In this case, the diameter b (mm) of the opening (drilled hole) 57 formed in the plate-shaped member 50A can be expressed by the formula "a + (30~50)". Specifically, the diameter b is 119mm to 139mm. The width c (mm) of the guide section 50 can be expressed by the formula "b + (100~150)".

[0075] The processing of the plate-shaped member 50A is performed before the rehabilitation pipe 10 is brought into the shaft M. As shown in Figure 12, before processing the plate-shaped member 50A, marking lines 51A may be drawn on the plate-shaped member 50A to match the processing dimensions. For example, a nail 150 is inserted into the center of the plate-shaped member 50A. The first end of a string 151 is connected to this nail 150, and the second end of the string 151, opposite to the first end, is connected to a writing instrument 152. While keeping the string 151 taut, a circular scribed line 51A is drawn on the plate-shaped member 50A using the writing instrument 152.

[0076] The tools used to process the plate-shaped member 50A into the guide portion 50 are not limited. For example, let's consider the case where the plate-shaped member 50A is made of a fiber-reinforced composite material. For ease of processing at the construction site, it is desirable to use processing tools such as power tools like the jigsaw 155 shown in Figure 13, or manual tools such as saws. Using the processing tools, cut the plate-shaped member 50A along the marking line 51A to form an opening 57 in the plate-shaped member 50A. The guide section 50 is fixed to the existing branch pipe 2 with anchor bolts 51. For this purpose, as shown in Figure 14, bolt holes 52A are drilled in the plate-shaped member 50A (guide section 50) at the positions through which the anchor bolts 51 will pass, using an electric drill 160 or the like. By performing the above steps, the guide portion 50 is manufactured from the plate-shaped member 50A.

[0077] As shown in Figure 11, the opening 57 of the guide plate 50 and the connection port 2a of the existing branch pipe 2 are arranged substantially coaxially with each other, and the opening 57 of the guide plate 50 is in communication with the connection port 2a of the existing branch pipe 2. One end 5a of the connecting pipe 5 is positioned inside the opening 57 of the guide section 50, and the connecting pipe 5 is in communication with the existing branch pipe 2.

[0078] In the second embodiment, an example in which an opening 57 is formed in a flat guide portion 50 will be described, but a cylindrical portion may be provided in the guide portion 50, and the opening of the cylindrical portion may be used as the opening.

[0079] With the guide section 50 fixed to the connection port 2a of the existing branch pipe 2, the branch pipe section 66 of the second rehabilitation pipe (rehabilitation pipe) 62 is aligned with the opening 57 of the guide section 50 in the pipe axis direction and the vertical direction (height direction). The aligned second rehabilitation pipe 62 is fixed in a state that prevents it from floating up. The second rehabilitation pipe 62 will be explained in detail later.

[0080] With the branch pipe section 66 aligned with the guide section 50, the connecting pipe 5 is inserted into the branch pipe section 66 from inside the second rehabilitation pipe 62. The inserted connecting pipe 5 is made to protrude from the branch pipe section 66, and one end 5a of the connecting pipe 5 is inserted into the opening 57 of the guide section 50 to align the connecting pipe 5 and the existing branch pipe 2. In this state, a piece of lumber or the like is driven into the gap between the connecting pipe 5 and the branch pipe section 66 to temporarily fix the connecting pipe 5 coaxially with the existing branch pipe 2.

[0081] With the connecting pipe 5 temporarily fixed coaxially to the existing branch pipe 2, the gap between one end 5a of the connecting pipe 5 and the opening 57 is filled with a resin mortar (epoxy resin-based two-component adhesive) not shown. As a result, the gap between one end 5a of the connecting pipe 5 and the opening 57 is filled, and the connecting pipe 5 is integrated with the guide section 50 and the existing pipe 1. In this way, the connecting pipe 5 is fixed in a state where it is generally coaxially connected to the existing branch pipe 2.

[0082] Next, the second rehabilitation pipe 62 of the second embodiment will be described with reference to Figures 15 and 16. The second rehabilitation pipe 62 of the second embodiment differs from the first embodiment only in that the branch pipe section 66 is eccentrically positioned upward with respect to the pipe axis 28; all other configurations are the same as those of the first embodiment.

[0083] Figure 15 is a side view showing the second rehabilitation pipe of the second embodiment. Figure 16 is a cross-sectional view broken along the line XV-XV in Figure 15. As shown in Figures 15 and 16, the second rehabilitation pipe 62 is provided with a mounting hole 76 in the outer circumferential wall of the rehabilitation main pipe 65. The mounting hole 76 is circular in shape, centered at the center in the direction of the pipe axis and eccentrically positioned upward by a distance H2 relative to the pipe axis 28, when viewed from the side of the rehabilitation main pipe 65. The branch pipe section 66 is connected to the periphery of the mounting hole 76 (i.e., the outer wall of the rehabilitation main pipe 65).

[0084] The branch pipe section 66 is formed in a cylindrical shape coaxially with the mounting hole 76, centered at the center in the direction of the pipe axis and eccentrically positioned upward by a distance H2 relative to the pipe axis 28, in a side view of the rehabilitated main pipe 65 (side view shown in Figure 15). In a side view of the rehabilitated main pipe 65 from the direction of the pipe axis (side view shown in Figure 16), the open end 66c of the branch pipe section 66 is formed in an arc shape centered on the pipe axis 28. Therefore, the open end 66c of the branch pipe section 66 can be formed along the outer circumferential wall of the rehabilitated main pipe 65. This prevents the open end 66c of the branch pipe section 66 from protruding significantly from the outer circumferential wall of the rehabilitated main pipe 65. Furthermore, the rehabilitated main pipe 65 and the branch pipe section 66 are integrally bonded together with the first FRP sheet 17 and the second FRP sheet 18. In the second embodiment, as an example, the main rehabilitated pipe 65 is formed with a diameter of 1650 mm, and the branch pipe section 66 is formed with a diameter of 800 mm. Note that the diameters of the main rehabilitated pipe 65 and the branch pipe section 66 can be arbitrarily selected.

[0085] As described above, the second rehabilitation pipe 62 of the second embodiment achieves the same effects and advantages as the second rehabilitation pipe 12 of the first embodiment. Furthermore, the guide section 50 is attached to the connection port 2a of the existing branch pipe 2. This makes it easier to connect pipes such as the connecting pipe 5 to the connection port 2a of the existing branch pipe 2 using the guide section 50. Furthermore, the rehabilitation method for existing pipes includes a guide section installation step. Therefore, pipes such as connecting pipes 5 can be easily connected to the connection port 2a of the existing branch pipe 2 using the guide section 50. Furthermore, the rehabilitation method for existing pipes does not necessarily require the installation of a guide section.

[0086] The second rehabilitation pipe 12 of this embodiment can be modified in various ways, as described below. In the first modified example of the second embodiment shown in Figure 17, a guide portion 80 is provided instead of the guide portion 50 of the second embodiment. The guide portion 80 has a cylindrical sleeve portion 81 and a flange portion 82 formed on the outer circumference of one end of the sleeve portion 81. The flange portion 82 is formed in an annular shape. Multiple bolt holes 82a are formed in the flange portion 82.

[0087] The installation work for attaching the guide section 80 to the existing pipe 1 is carried out as follows. Prior to installation, multiple anchor bolts 51 are attached to the periphery of the connection port 2a of the existing branch pipe 2 on the inner surface of the existing pipe 1. It is preferable that the multiple anchor bolts 51 are arranged at equal intervals around the connection port 2a of the existing branch pipe 2. First, the flange portion 82 of the guide portion 80 is placed against the connection port 2a of the existing branch pipe 2, and the flange portion 82 is brought into contact with the inner surface of the existing pipe 1. At this time, the sleeve portion 81 of the guide portion 80 is positioned to protrude toward the inside of the existing pipe 1. Multiple bolt holes 82a of the flange portion 82 are placed against multiple anchor bolts 51. The shafts of the anchor bolts 51 are inserted through the multiple bolt holes 82a of the flange portion 82. The guide portion 80 is fastened to the existing pipe 1 by screwing nuts 83 onto the anchor bolts 51.

[0088] In addition to fastening with anchor bolts 51 and nuts 83, a two-component epoxy resin adhesive capable of joining concrete and polyvinyl chloride resin members may also be used to attach the guide section 80 to the existing pipe 1.

[0089] As shown in the second modified example of the second embodiment in Figure 18, the guide portion 85 does not necessarily have a sleeve portion 81 for each component of the guide portion 80. That is, the guide portion 85 has a flange portion 82.

[0090] As shown in the third modified example of the second embodiment in Figure 19, the existing branch pipe 2 and the connecting pipe 5 may be connected. That is, the connecting pipe 5 is temporarily fixed coaxially with the existing branch pipe 2. In this state, joint filling is performed between the connection port 2a of the existing branch pipe 2 and one end 5a of the connecting pipe 5. The joint filling process is carried out by removing the aforementioned timber and filling the joint with, for example, a two-component epoxy resin-based adhesive such as resin mortar (not shown). As a result, the gap between one end 5a of the connecting pipe 5 and the connection port 2a of the existing branch pipe 2 is filled, and the connecting pipe 5 is integrated with the guide section 80 and the existing pipe 1. In addition, the connecting pipe 5 is fixed in a state where it is in roughly coaxial communication with the existing branch pipe 2.

[0091] The connection between the existing branch pipe 2 and the connecting pipe 5, and the joint between the guide section 80 and the connecting pipe 5, are sealed by applying or filling them with caulking material (sealant) 90. The caulking material 90 is preferably composed mainly of synthetic resin materials such as silicone resin, acrylic resin, or urethane resin. The caulking material 90 is applied or filled into these parts using an extruder 92 such as a caulking gun. This allows for watertight sealing of joints between the existing branch pipe 2 and the connecting pipe 5. Furthermore, since the existing branch pipe 2 and the connecting pipe 5 can be closely joined so that their inner surfaces are almost continuous, the watertight sealing effect is significantly enhanced, and all the water flowing from the existing branch pipe 2 can be guided to the rehabilitated pipe 10.

[0092] It should be noted that the technical scope of the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention.

[0093] For example, in the first embodiment described above, an example was described in which the second rehabilitation pipe 12 is rotated around its axis by performing a rotation process in the middle of the second process to align the branch pipe section 16 in the vertical direction (height direction) with respect to the connection position, but the invention is not limited to this. As another example, the rotation process may be performed between the second process and the third process. That is, the second rehabilitation pipe 12 may be rotated around its axis by performing a rotation process between the second process and the third process to align the branch pipe section 16 in the vertical direction (height direction) with respect to the connection position.

[0094] Furthermore, without departing from the spirit of the present invention, the components in the above embodiments may be replaced with well-known components as appropriate, and the above-described modifications may be combined as appropriate. [Explanation of Symbols]

[0095] 1...Existing pipe, 2...Existing branch pipe, 12, 62...Second rehabilitation pipe (rehabilitation pipe), 15, 65...Rehabilitation main pipe, 16, 66...Branch pipe section, 28...Pipe axis, 16c, 66c...Open end, 17...First FRP sheet (FRP sheet), 18...Second FRP sheet (FRP sheet), 50, 80, 85...Guide section, M...Shaft (vertical hole).

Claims

1. A rehabilitation pipe for rehabilitating an existing pipe to which an existing branch pipe is connected, The rehabilitation headquarters and, It comprises a branch pipe section that is branched from the main rehabilitation pipe and has a smaller diameter than the main rehabilitation pipe, A rehabilitated pipe characterized in that, in a side view of the branch pipe section viewed from the direction of the pipe axis of the rehabilitated main pipe, the open end of the branch pipe section is in the shape of an arc centered on the pipe axis.

2. The rehabilitation pipe according to claim 1, characterized in that the diameter of the branch pipe section is 500 mm or more.

3. The rehabilitation pipe according to claim 1 or 2, characterized in that the rehabilitation main pipe and the branch pipe section are made of fiber-reinforced plastic.

4. The rehabilitation pipe according to claim 1 or 2, characterized in that the rehabilitation main pipe and the branch pipe section are separate components and are bonded together with a sheet material.

5. The rehabilitation pipe according to claim 1, characterized in that a guide portion is attached to the connection port of the existing branch pipe.

6. A method for rehabilitating an existing pipe to which an existing branch pipe is connected, using a rehabilitation pipe as described in claim 1 or 2, A transport process for transporting the rehabilitation pipe within the existing pipe, A method for rehabilitating an existing pipe, characterized by comprising a connection step of inserting a connecting pipe into the branch pipe section from inside the rehabilitated pipe and connecting the connecting pipe to the existing branch pipe.

7. The method for rehabilitating an existing pipe according to claim 6, characterized in that the rehabilitated pipe is rotated around its axis during the transport process or between the transport process and the connection process.

8. The method for rehabilitating an existing pipe according to claim 6, further comprising a guide part installation step of installing a guide part at the connection port of the existing branch pipe before the connection step.

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