Existing pipe rehabilitating method and existing pipe rehabilitating spacer device

Abstract

To surely install a spacer near an uneven part of an existing pipe, and to prevent an uneven transfer mark such as a step transfer mark from being formed on a regeneration pipe.SOLUTION: After the regeneration pipe 3 is constructed in the existing pipe 1, the existing pipe 1 is regenerated by filling the back-filling space 2 with a back-filling material. Prior to the construction of the regeneration pipe 3, a long spacer 11 is installed on the 1a of a linear part along the pipe axial direction on the inner peripheral surface of the existing pipe 1 with the longitudinal direction directed to the pipe axial direction. A shape-changeable bar-like or lump-like irregular spacer 20 is installed on the 1d in the vicinity of the uneven part including the uneven part 1b on the inner peripheral surface of the existing pipe 1.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for rehabilitating existing pipes, such as aging sewer pipes, and a spacer device used for rehabilitating existing pipes, and in particular to a rehabilitation method for constructing a rehabilitated pipe within an existing pipe, and a spacer device for rehabilitating existing pipes to ensure a backfill space between the rehabilitated pipe and the existing pipe. [Background technology]

[0002] A known method for rehabilitating existing pipes such as aging sewer pipes involves lining the inner periphery of the existing pipe with a rehabilitation pipe and filling the gap between the outer periphery of the rehabilitation pipe and the inner periphery of the existing pipe with backfill material (see Patent Documents 1 to 3, etc.). Patent Document 1 describes how, prior to lining the rehabilitating pipe, a straight, elongated steel spacer is installed on the inner surface of the upper half of the existing pipe in an adjustable height, and the outer surface of the upper half of the rehabilitating pipe is placed against the elongated spacer. This ensures a backfill space between the existing pipe and the rehabilitating pipe, i.e., a clearance for injecting backfill material. This prevents the rehabilitating pipe from floating up during backfilling.

[0003] Patent documents 2 and 3 disclose a self-propelled pipe-making device that makes a spiral-shaped rehabilitation pipe from a strip-shaped member that fits the inner circumference of an existing pipe. This pipe-making device can accommodate uneven parts of the existing pipe, such as steps and irregularities, by making the rehabilitation pipe so that the diameter of the pipe can be expanded or contracted. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-082430 [Patent Document 2] International Publication No. WO2016 / 175243 [Patent Document 3] Japanese Patent Publication No. 2021-169164 Summary of the Invention [Problem to be solved by the invention]

[0005] The long spacers of Patent Document 1 are rigid and non-deformable, so they can be installed relatively easily on straight sections of the inner surface of an existing pipe along the pipe axis, but they are difficult to install near uneven sections including steps, irregularities, bends, etc. on the inner surface of the existing pipe, and installation defects (gaps) may occur.For this reason, even if the pipe manufacturing device of Patent Documents 2 and 3 is used to expand and shrink a rehabilitating pipe so that it overcomes steps in the existing pipe, the buoyancy force generated during subsequent backfilling may cause the rehabilitating pipe to be pressed hard against the steps in the existing pipe, which may leave dents on the inner surface of the rehabilitating pipe. In view of the above circumstances, the present invention aims to provide a method for rehabilitating existing pipes and a spacer device for rehabilitating existing pipes that can reliably install spacers in areas near unevenness, including uneven sections of existing pipes, and that can prevent unevenness transfer marks such as step transfer marks from being formed on the rehabilitated pipe. [Means for solving the problem]

[0006] In order to solve the above problem, the present invention provides a method for rehabilitating an existing pipe, in which a rehabilitating pipe is constructed in an existing pipe, and then a backfill material is filled into a backfill space between the existing pipe and the rehabilitating pipe, Prior to constructing the rehabilitation pipe, a step of installing a long spacer in a linear portion along a pipe axis direction on an inner peripheral surface of the existing pipe, with the longitudinal direction of the spacer facing the pipe axis direction; a step of placing a shape-changeable strip-like or block-like irregular spacer in an area near the unevenness including the unevenness on the inner circumferential surface of the existing pipe; The present invention is characterized by carrying out the following steps.

[0007] The elongated spacers are preferably straight, rigid members that can be easily installed in straight sections. The irregular spacer can be reliably installed near uneven areas by freely changing its shape according to the unevenness of the surface, such as steps, irregularities, and bends, and it is possible to prevent the occurrence of missing spacer installation areas (gaps) in the uneven areas. The rehabilitating pipe is then constructed. A spacer device for rehabilitating an existing pipe is placed between the rehabilitating pipe and the existing pipe to ensure a backfill space, allowing the backfill material to be injected and filled reliably. During the backfilling process, the existing pipe rehabilitation spacer device can also function as a floating prevention device, preventing the rehabilitated pipe from floating up due to the buoyancy of the backfill material. In areas near unevenness, irregular spacers installed without any installation defects are interposed between the rehabilitated pipe and the uneven area, preventing the rehabilitated pipe from being pressed directly against the uneven area. This prevents unevenness transfer marks, such as step transfer marks, from being formed on the rehabilitated pipe.

[0008] Preferably, the irregular spacer is a chain in which adjacent chain elements are aligned in a row so as to be displaceable relative to each other, and the chain is installed in the vicinity of the unevenness with its extension along the pipe axis direction. The chain constitutes a strip-shaped irregular spacer. The chain can be easily reshaped to accommodate unevenness such as steps, bumps, and bends, and can be reliably installed near uneven areas without any installation defects. The chain reliably prevents the rehabilitating pipe from floating up during backfilling, and reliably prevents the formation of unevenness transfer marks on the rehabilitating pipe.

[0009] Preferably, the chain (stripe-shaped irregular spacer) is a roller chain, which has links arranged in a row and rollers that rotatably connect adjacent links, and is installed near the uneven area in the upper half or side of the existing pipe, with the rotation axes of the rollers oriented circumferentially. The roller chain is free to deform in the direction perpendicular to the rotation axis of the rollers, but is restricted from deformation in the width direction, which is parallel to the rotation axis of the rollers. By orienting the rotation axis of the rollers in the circumferential direction of the pipe, the roller chain can be stretched along the pipe diameter while freely deforming in the pipe diameter direction to fit uneven parts. In the upper half of the existing pipe, the rotation axis of the rollers of the roller chain is oriented almost horizontally, which makes it easy to install the roller chain along uneven areas such as steps in the upper half of the existing pipe. At the side of the existing pipe, the rotation axis of the rollers of the roller chain is oriented vertically, which makes it easy to install the roller chain according to the curves of the existing pipe. Roller chains exhibit high resistance to deformation (rigidity) in the circumferential direction of the pipe, which prevents irregular spacers from deforming in the circumferential direction when constructing or backfilling a rehabilitated pipe. Preferably, the links and rollers are made of a metal such as steel, which provides the roller chain with sufficient load-bearing strength against loads due to buoyancy and fluid pressure during backfilling.

[0010] Preferably, the chain is stretched from the straight portion to the portion near the unevenness, and the portion of the chain stretched over the straight portion serves as the elongated spacer. This allows one chain to be used as an irregular spacer and an elongated spacer.

[0011] A hardening viscous material having a higher hardening initiation viscosity and hardening speed than the backfilling material is brought into close contact with the uneven surface, and the chain is placed on the inner surface of the hardening viscous material. The hardening viscous material can be easily adapted to fit the unevenness of existing pipes, such as steps, bumps, and bends, and can be easily installed without causing any installation defects. This makes it possible to smooth out and smooth out unevenness, thereby facilitating the construction of rehabilitating pipes in areas near unevenness. A backfill space can be secured by placing a chain between the hardening viscous material and the rehabilitating pipe. During the backfilling process, the buoyancy force on the rehabilitating pipe can be received by the hardening viscous material and the chain. This reliably prevents the formation of unevenness marks, such as step marks, on the rehabilitating pipe. Furthermore, by supporting the chain with the hardening viscous material, it is possible to prevent the chain from being deformed near the unevenness and ultimately toward the unevenness.

[0012] As the irregular spacer, a hardening viscous material having a higher hardening initiation viscosity and hardening speed than the backfilling material may be brought into close contact with the uneven area, and the chain may be omitted. The hardening viscous material forms lumpy, irregular spacers, which can smooth out and smooth out unevenness.

[0013] Preferably, the hardening viscous body has a receiving protrusion that protrudes from a base portion that is in close contact with the uneven portion toward the inside of the existing pipe and is capable of coming into contact with the rehabilitating pipe. This allows a backfilling space of a size corresponding to the height of the receiving protrusions to be secured between the base of the hardening viscous material and the rehabilitating pipe. During the backfilling process, the rehabilitating pipe comes into contact with the receiving protrusions, preventing the rehabilitating pipe from floating.

[0014] The present invention provides a spacer device for rehabilitating an existing pipe, which is installed in a backfill space between a rehabilitation pipe to be constructed within an existing pipe and the existing pipe, and a long spacer installed in a linear portion along the pipe axis direction on the inner peripheral surface of the existing pipe, with its longitudinal direction directed in the pipe axis direction; a shape-changeable strip-like or block-like irregular spacer to be installed in the vicinity of the unevenness including the unevenness on the inner circumferential surface of the existing pipe; The present invention is characterized by the following. The elongated spacers are preferably rigid and non-deformable. The irregular spacer, which is installed near the unevenness of an existing pipe, can be freely changed in shape depending on the unevenness of the pipe. This allows the spacer to be installed reliably near the unevenness without any damage. A backfill space can be secured by interposing an existing pipe rehabilitation spacer device between the inner periphery of the existing pipe and the outer periphery of the rehabilitation pipe. The backfill material is injected and filled into the backfill space. The existing pipe rehabilitation spacer device can also function as a floating prevention device that prevents the rehabilitated pipe from floating up due to the buoyancy of the backfill material. In this case, in areas near uneven ground, irregular spacers are interposed between the rehabilitated pipe and the uneven area, preventing the formation of unevenness transfer marks, such as step transfer marks, on the rehabilitated pipe.

[0015] Preferably, the irregular spacer includes a chain in which adjacent chain members arranged in a row are linked so as to be displaceable relative to each other. The chain can be easily reshaped to fit the unevenness, allowing it to be installed near the unevenness without any installation defects. By placing the chain between the rehabilitating pipe and the unevenness, it is possible to secure backfill space and reliably prevent the rehabilitating pipe from floating up during backfilling, thereby reliably preventing the formation of unevenness transfer marks on the rehabilitating pipe.

[0016] Preferably, the end of the chain is connected to the elongated spacer. This allows the end of the chain to be fixed to the existing pipe via the long spacer.

[0017] Preferably, the chain is a roller chain having links arranged in a row and rollers rotatably connecting adjacent links. The roller chain is deformable in a direction perpendicular to the rotation axis of the rollers, but has high rigidity in the width direction parallel to the rotation axis of the rollers. Preferably, the roller chain is installed in the upper half or side of the existing pipe with the rotation axes of the rollers oriented in the circumferential direction of the pipe. In the upper half of the existing pipe, the rotation axis of the rollers of the roller chain is oriented almost horizontally, which makes it easy to install the roller chain along uneven areas such as steps in the upper half of the existing pipe. At the side of the existing pipe, the rotation axis of the rollers of the roller chain is oriented vertically, which makes it easy to install the roller chain according to the curves of the existing pipe.

[0018] Preferably, the irregular spacer further includes a housing having both longitudinal ends open, and the chain is passed through the interior of the housing. This allows the cross-sectional area of ​​the strip-shaped irregular spacer to be increased. The chain can be surrounded and protected by the housing, further increasing the strength of the irregular spacer. A plurality of housings may be arranged in a line and connected by a chain.

[0019] Preferably, the elongated spacer includes a spacer body having the same cross-sectional shape and made of the same material as the housing. This allows the member 1 to be used as a housing or as a spacer body. More preferably, the length of the housing is shorter than the spacer body, so that the spacer body can be cut to a short length and used as the housing.

[0020] Preferably, the irregular spacer further includes a mass formed by hardening a hardening viscous material having a higher hardening initiation viscosity and hardening speed than the backfilling material backfilled into the backfilling space, the mass being in close contact with the uneven area, and the chain being provided on the inner surface of the mass. The hardening viscous material and hence the mass constitute the mass-like irregular spacer. The unhardened hardening viscous material can be freely changed in shape to fit unevenness in existing pipes, such as steps, bumps, and bends, and can smooth out and smooth out unevenness. By forming an irregular spacer using a chain and a hardened mass of the hardening viscous material, the irregular spacer can be reliably installed near uneven areas without any damage. By interposing a chain between the mass and the rehabilitating pipe, a backfill space of a size corresponding to the thickness or height of the chain can be secured between the mass and the rehabilitating pipe. By providing the housing around the outer periphery of the chain, a backfill space of a size corresponding to the height of the housing can be secured, thereby making the backfill space larger. In addition, the chain can be prevented from sinking into the hardening viscous material. During backfilling, the buoyancy of the rehabilitating pipe can be supported by the mass and chain, which reliably prevents the formation of unevenness marks, such as step marks, on the rehabilitating pipe. Furthermore, by supporting the chain with the mass, it is possible to prevent the chain from being deformed near the unevenness and ultimately toward the unevenness itself.

[0021] Preferably, the irregular spacer includes a mass formed by hardening a hardening viscous material having a higher hardening initiation viscosity and a higher hardening rate than the backfilling material to be backfilled into the backfill space, and the mass may be adhered to the vicinity of the unevenness. The irregular spacer may be constituted by a mass of irregular spacers, and a strip-like irregular spacer such as a chain may be omitted. The hardening viscous material can be freely shaped to fit unevenness in the existing pipe, such as steps, bumps, and bends, and can smooth out and smooth out the unevenness. This makes it easier to build rehabilitated pipes near uneven areas. When backfilling, the mass can reliably support the buoyancy of the rehabilitated pipe.

[0022] Preferably, the mass includes a base portion that is tightly attached to the uneven area, and a receiving protrusion that protrudes from the base portion toward the inside of the existing pipe and can abut against the rehabilitation pipe, and the width of the receiving protrusion along the circumferential direction of the pipe is smaller than the width of the base portion along the circumferential direction of the pipe. This allows a backfill space of a size corresponding to the height of the receiving protrusions to be secured between the base of the hardening viscous material and the rehabilitating pipe. When backfilling, the rehabilitating pipe hits the receiving protrusions, preventing the rehabilitating pipe from floating. [Effects of the Invention]

[0023] According to the present invention, the existing pipe rehabilitation spacer can be reliably installed in the vicinity of the unevenness of the existing pipe. When backfilling, it is possible to prevent the formation of unevenness transfer marks such as step transfer marks on the rehabilitated pipe. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a cross-sectional view taken along the pipe axis of an existing pipe that has been rehabilitated using an existing pipe rehabilitating spacer device according to a first embodiment of the present invention. [Figure 2]Figure 2(a) is a cross-sectional view of the rehabilitated existing pipe taken along line IIa-IIa in Figure 1. Figure 2(b) is a cross-sectional view of the rehabilitated existing pipe taken along line IIb-IIb in Figure 1. Figure 2(c) is a cross-sectional view of the rehabilitated existing pipe taken along line IIc-IIc in Figure 1. Figure 2(d) is a cross-sectional view of the rehabilitated existing pipe taken along line IId-IId in Figure 1. [Figure 3] Figure 3(a) is a plan view of the long spacer of the existing pipe rehabilitation spacer device as seen from outside the pipe. Figure 3(b) is a bottom view of the long spacer as seen from inside the pipe. Figure 3(c) is a cross-sectional view taken along line IIIc-IIIc in Figure 3(a). Figure 3(d) is a cross-sectional view taken along line IIId-IIId in Figure 3(c). [Figure 4] Fig. 4(a) is a front view of an irregular spacer of the existing pipe rehabilitating spacer device, Fig. 4(b) is a plan view of the irregular spacer, and Fig. 4(c) is a plan view showing a modified example of the irregular spacer. [Figure 5(a)] FIG. 5(a) is a cross-sectional view showing a state in which the irregular spacer of the existing pipe rehabilitating spacer device is installed in the vicinity of an uneven portion of an existing pipe. [Figure 5(b)] FIG. 5(b) is a cross-sectional view showing a modified example of the irregular spacer of the existing pipe rehabilitating spacer device installed in the vicinity of the uneven surface. [Figure 6] FIG. 6 is a cross-sectional view of an existing pipe showing a process of lining a rehabilitating pipe after the installation of the existing pipe rehabilitating spacer device. [Figure 7] FIG. 7 shows the second embodiment of the present invention and is a plan view showing an example of an installation state of an existing pipe rehabilitating spacer device at a bend in an existing pipe. [Figure 8] FIG. 8 shows the third embodiment of the present invention and is a plan view showing another example of an installation state of an existing pipe rehabilitating spacer device at a bend in an existing pipe. [Figure 9] FIG. 9 is a cross-sectional view showing a state in which an irregular spacer of an existing pipe rehabilitating spacer device according to a fourth embodiment of the present invention is installed in the vicinity of an uneven portion of an existing pipe. [Figure 10]Fig. 10(a) is a cross-sectional view of the irregular spacer according to the fourth embodiment taken along line Xa-Xa in Fig. 9. Fig. 10(b) is a cross-sectional view showing a modified example of the irregular spacer according to the fourth embodiment. [Figure 11] FIG. 11 is a cross-sectional view taken along the pipe axis of an existing pipe that has been rehabilitated using an existing pipe rehabilitating spacer device according to a fifth embodiment of the present invention. [Figure 12] FIG. 12 is a cross-sectional view taken along the pipe axis of an existing pipe that has been rehabilitated using an existing pipe rehabilitating spacer device according to the sixth embodiment of the present invention. [Figure 13] Figure 13(a) is a cross-sectional view perpendicular to the pipe axis of the uneven portion of the existing pipe, showing the rehabilitation process in the sixth embodiment, with the hardening viscous material of the irregular spacer of the existing pipe rehabilitation spacer device installed in the uneven portion of the existing pipe. Figure 13(b) is a cross-sectional view perpendicular to the pipe axis of the uneven portion of the existing pipe, showing the rehabilitation process in the sixth embodiment, with the roller chain of the irregular spacer of the existing pipe rehabilitation spacer device installed in the uneven portion. Figure 13(c) is a cross-sectional view perpendicular to the pipe axis of the existing pipe in the uneven portion of the existing pipe, showing the rehabilitation process in the sixth embodiment, with the rehabilitated pipe constructed. Figure 13(d) is a cross-sectional view taken along line XIIId-XIIId in Figure 12, showing the rehabilitation process in the sixth embodiment, with the backfill material filled in the backfill space between the existing pipe and the rehabilitated pipe. [Figure 14] Figure 14 is a cross-sectional view along line XIV-XIV in Figure 15(a), showing an irregular spacer of the existing pipe rehabilitation spacer device of the seventh embodiment of the present invention installed near an uneven area of ​​an existing pipe. [Figure 15]Figure 15(a) is a cross-sectional view perpendicular to the pipe axis of the uneven portion of the existing pipe, showing the rehabilitation process in the seventh embodiment, with the irregular spacer of the existing pipe rehabilitation spacer device installed in the uneven portion of the existing pipe. Figure 15(b) is a cross-sectional view perpendicular to the pipe axis of the uneven portion of the existing pipe, showing the rehabilitation process in the seventh embodiment, with the rehabilitated pipe constructed. Figure 15(c) is a cross-sectional view perpendicular to the pipe axis of the uneven portion of the existing pipe, showing the rehabilitation process in the seventh embodiment, with the backfill material filled in the backfill space between the existing pipe and the rehabilitated pipe. [Figure 16] FIG. 16 is a stepped cross-sectional view showing an existing pipe rehabilitated using an existing pipe rehabilitating spacer device according to the eighth embodiment of the present invention, taken along line XVI-XVI in FIG. 17(c). [Figure 17] Figure 17(a) is a cross-sectional view perpendicular to the pipe axis of the uneven portion of the existing pipe, showing the rehabilitation process in the eighth embodiment, with the irregular spacer of the existing pipe rehabilitation spacer device installed in the uneven portion of the existing pipe. Figure 17(b) is a cross-sectional view perpendicular to the pipe axis of the uneven portion of the existing pipe, showing the rehabilitation process in the seventh embodiment, with the rehabilitated pipe constructed. Figure 17(c) is a cross-sectional view perpendicular to the pipe axis of the uneven portion of the existing pipe, showing the rehabilitation process in the seventh embodiment, with the backfill material filled in the backfill space between the existing pipe and the rehabilitated pipe. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. <First embodiment (FIGS. 1 to 6)> Figure 1 shows an existing pipe 1 that has been rehabilitated. The existing pipe 1 is a sewer pipe buried underground, but it is not limited to this and may also be a water supply pipe, an agricultural irrigation pipe, a hydroelectric power generation water pipe, a gas pipe, or a tunnel.

[0026] As shown in Figure 1, the inner surface of an aged existing pipe 1 has a straight section 1a and an uneven section 1b. The straight section 1a extends smoothly and straight along the axial direction of the existing pipe 1 (the left-right direction in Figure 1), and has no unevenness or only a sufficiently small degree of unevenness. The uneven section 1b includes uneven sections such as steps and irregularities, and their vicinity.

[0027] In this embodiment, the existing pipe 1 is made up of multiple (only two are shown in FIG. 1) straight pipes 1p connected in a row. Two adjacent pipes 1p are vertically shifted from each other, forming a step 1d (uneven portion) between these pipes 1p. The uneven portion 1b is made up of the step 1d and a portion 1ba of the pipe 1p upstream of the step 1d (left side in FIG. 1).

[0028] As shown in Figure 1, a rehabilitation pipe 3 is lined along the inner periphery of an existing pipe 1. The rehabilitation pipe 3 is a helical pipe formed by spirally winding a long strip-shaped member 5 made of synthetic resin. The rehabilitation pipe 3 has a rehabilitation straight pipe section 3a located within the straight section 1a excluding the step vicinity section 1ad downstream of the step 1d (right side in Figure 1), an in-unevenness rehabilitation pipe section 3b located within the unevenness vicinity section 1b, and a transition rehabilitation pipe section 3c located within the step vicinity section 1ad. As shown in Figures 2(a) and 2(d), the rehabilitation straight pipe section 3a is formed with a constant cross section, for example, a substantially circular shape, to match the circular cross section of the straight section 1a.

[0029] As shown in Figure 2(b), the inside-unevenness rehabilitating pipe section 3b is formed with an elliptical cross section, for example, with the major axis oriented left and right and the minor axis oriented up and down. In the inside-unevenness rehabilitating pipe section 3b, the cross section changes as the circumferential length, pipe diameter (major axis and minor axis), ellipticity, etc. change depending on the position in the pipe axis direction. Specifically, as shown in Figure 1, the inside-unevenness rehabilitating pipe section 3b is reduced in diameter as it approaches the step 1d, with the circumferential length and the minor axis oriented up and down becoming smaller.

[0030] As shown in Fig. 2(c), the transition rehabilitating pipe section 3c has an elliptical cross section with its major axis oriented left and right and its minor axis oriented up and down. As shown in Fig. 1, the transition rehabilitating pipe section 3c has an increased circumferential length and an increased minor axis oriented up and down as it moves away from the step 1d, thereby expanding its diameter.

[0031] As shown in Figures 2(a) to 2(d), an annular backfill space 2 is formed between an existing pipe 1 and a rehabilitation pipe 3. The backfill space 2 is filled with a backfill material 4. The backfill material 4 is made of mortar or cement milk.

[0032] As shown in Figures 1 and 2, an existing pipe rehabilitation spacer device 10 is provided in the backfill space 2 between the inner circumferential surface of the upper half of the existing pipe 1 (the portion from the top to the side) and the rehabilitation pipe 3. Preferably, the existing pipe rehabilitation spacer device 10 is disposed on the inner circumferential surface near the top or in the upper portion of the existing pipe 1. The existing pipe rehabilitation spacer device 10 includes a plurality of elongated spacers 11 and irregular spacers 20, and extends along the axial direction of the existing pipe 1 (left and right in Figure 1). The elongated spacers 11 are disposed in the straight portion 1a (including the portion 1ad near the step).

[0033] As shown in Figure 3, the elongated spacer 11 includes a spacer body 12 and an attachment means 13. As shown in Figures 3(a) and 3(b), the spacer body 12 is made of a metal such as steel with a constant cross section and a straight shape. The spacer body 12, and therefore the elongated spacer 11, is rigid and does not easily deform. As shown in Figure 3(d), the cross section of the spacer body 12 is formed, for example, in a U-shape or C-shape (open ring). The spacer body 12 may also be made of a flat bar (flat steel).

[0034] As shown in Fig. 3(b), a plurality of nuts 14 are attached to the spacer body 12 by welding or the like at intervals in the longitudinal direction. Female threaded holes 14a are formed in the nuts 14. In other words, the spacer body 12 has a plurality of female threaded holes 14a. The female threaded holes 14a penetrate the spacer body 12 through the through holes 12a of the spacer body 12.

[0035] As shown in Figures 3(a) and 3(b), a plurality of engagement holes 15 are formed in the spacer body 12. Each engagement hole 15 is an elongated hole with its major axis directed in the longitudinal direction of the spacer body 12 (the left-right direction in Figure 3(b)). The plurality of engagement holes 15 are arranged at intervals in the longitudinal direction of the spacer body 12.

[0036] As shown in FIG. 1, the longitudinal direction of the spacer body 12 is oriented in the pipe axis direction of the existing pipe 1. As shown in FIG. 3(c), the spacer body 12 is attached to the inner circumferential surface of the existing pipe 1 via an attachment means 13. The attachment means 13 includes a plurality of set screws 16 (protruding and retracting members) and screw anchors 17 (fixing members). The set screws 16 are threaded into each female screw hole 14a. The set screws 16 are capable of protruding and retracting from the spacer body 12 toward the inner circumferential surface of the existing pipe 1. The maximum amount of protrusion of the set screws 16 from the spacer body 12 is preferably approximately 20 mm.

[0037] 3(c), a screw anchor 17 is fastened to a fastening hole 15 in a part of the spacer body 12. The screw anchor 17 is driven into the existing pipe 1 through the fastening hole 15.

[0038] By adjusting the protruding amount of the set screw 16 and the driving amount of the screw anchor 17, the spacer body 12 and therefore the elongated spacer 11 are engaged with the inner peripheral surface of the existing pipe 1 so that they can move toward and away from the inner peripheral surface of the existing pipe 1 and can be fixed thereto. As shown in Figures 3(c) and 3(d), when the elongated spacer 11 is fixed, the heads of the screw anchors 17 are caught in the engaging holes 15, preventing the spacer body 12 from moving away from the inner peripheral surface of the existing pipe 1. Furthermore, the set screw 16 protruding from the spacer body 12 abuts against the inner peripheral surface of the existing pipe 1, preventing the spacer body 12 from moving toward the inner peripheral surface of the existing pipe 1. Alternatively, although not shown, the set screw 16 may be retracted into the spacer body 12, causing the spacer body 12 to abut against the inner peripheral surface of the existing pipe 1.

[0039] 1, a plurality of long spacers 11 are arranged in a row along the pipe axis direction on the inner peripheral surface of the upper half of the straight section 1a of the existing pipe 1. Adjacent long spacers 11 may be connected to each other by a connecting means (not shown), or may simply be abutted against each other without being connected, or may be spaced apart from each other within a predetermined distance (for example, within 50 mm).

[0040] As shown in Figure 1, an irregular spacer 20 is provided in the upper half of the uneven portion 1b of the existing pipe 1. The irregular spacer 20 has no fixed shape and can be freely deformed to fit the uneven portion 1b. Preferably, the irregular spacer 20 is made of a shape-deformable elongated strip. The irregular spacer 20 has tensile strength sufficient to resist the buoyancy applied to the rehabilitating pipe 3 during backfilling.

[0041] Preferably, the strip-like irregular spacer 20 is configured by a chain made up of chain elements 21 aligned in a line in the extension direction. Adjacent chain elements 21 are connected to each other so as to be capable of relative rotation (relative displacement).

[0042] As shown in Figures 4(a) and 4(b), more preferably, the irregular spacer 20 is configured by a roller chain 22. The roller chain 22 has inner links 23 and outer links 24 arranged alternately in a line in the extension direction, and rollers 25 that rotatably connect the adjacent inner and outer links 23, 24 to each other. The rotation axis L of the roller 25 25 are oriented in the width direction of the roller chain 22 (the direction perpendicular to the plane of the paper in FIG. 4(a)). The chain body 21 is made up of one roller 25 and one link 23 or 24. Preferably, the links 23, 24 and roller 25 are made of steel (metal) having the required strength. Consequently, the roller chain 22 has sufficient load-bearing strength to withstand loads due to buoyancy and fluid pressure during backfilling. The roller chain 22 may have a single-row structure (FIG. 4(b)) or a double-row structure with two or more rows (FIG. 4(c)).

[0043] As shown in FIG. 5(a), the opposing ends of two elongated spacers 11A and 11B, which are arranged on either side of a step 1d in the existing pipe 1 in the pipe axial direction (left-right direction in FIG. 5), are offset, for example, vertically. An irregular spacer 20 is diagonally bridged between the opposing ends of these two elongated spacers 11A and 11B. As a result, the irregular spacer 20 is positioned so as to cover the unevenness-proximate portion 1b from the inside of the pipe (the lower side in FIG. 5(a)). Both ends of the irregular spacer 20 in the extension direction are preferably rotatably connected to the ends of the corresponding elongated spacers 11A and 11B via connecting pins 26. As a result, both ends of the irregular spacer 20 are fixed to the existing pipe 1 via the elongated spacers 11A and 11B.

[0044] As shown in FIG. 5(a), the distance L along the tube axis from the step 1d to the end of the irregular spacer 20 on the side of the elongated spacer 11A is A The length of the unevenness vicinity 1b depends on the level of the unevenness such as the height of the step 1d, but is at least the length of one link 23 or 24 or the length of one chain body 21, and is preferably L A = several tens of centimeters to several meters, more preferably L A = about 1m.

[0045] As shown in FIG. 5(a), the rotation axis L of the roller 25 of the roller chain 22 when installed in the existing pipe 1 25 are oriented along the circumferential direction of the existing pipe 1 (the direction perpendicular to the plane of the paper in FIG. 5). This allows each link 23, 24 to rotate and displace in the radial direction of the existing pipe 1. Therefore, the irregular spacer 20 as a whole is flexibly deformable in the radial direction of the pipe, but has high rigidity and is immovable in the circumferential direction of the pipe. In this embodiment, the roller chain 22 is disposed near the upper part or top of the existing pipe 1, so that the rotation axis L of the rollers 25 is 25 The irregular spacer 20 as a whole is flexibly deformable in the vertical direction, but is unable to deform horizontally.

[0046] 5(a), the irregular spacer 20 is preferably installed so as to extend straight with almost no slack, so that tension acts on the irregular spacer 20.

[0047] As shown by the solid line in Fig. 5(b), the irregular spacer 20 may be installed so as to be slightly loose. In this case, the straight line L connecting both ends of the irregular spacer 20 20 Distance d from the maximum separation part of the irregular spacer 20 20 max is preferably d 20 max = about 1 mm to 5 mm. The amount of slack in the irregular spacer 20 in Figure 5(b) is exaggerated relative to the size of the links 23, 24 and the rollers 25. As shown by the two-dot chain line in Figure 5(b), the irregular spacer 20 with slack can deform toward the step 1d when it receives a force F toward the outside of the pipe from the rehabilitating pipe 3 or the like that will be constructed after installation. On the other hand, the irregular spacer 20 cannot deform until it completely conforms to the step 1d (the state shown by the three-dot chain line in Figure 5), as the slack is eliminated and tension is applied to the spacer before it conforms to the step 1d.

[0048] Using the existing pipe rehabilitation spacer device 10, the existing pipe 1 is rehabilitated as follows. As shown in FIG. 5(a), prior to lining (pipe manufacturing) of the rehabilitation pipe 3, an installation work of an existing pipe rehabilitation spacer device 10 is carried out. A long spacer 11 is placed on the straight portion 1a (long spacer placing step). An irregular spacer 20 is installed in the uneven area 1b (irregular spacer installation process). Both ends of the irregular spacer 20 are connected to the elongated spacers 11A and 11B. The irregular spacer 20 can be freely deformed according to the height of the step 1d, etc., and can be installed reliably and easily in the uneven area 1b. There is no need to tilt or forcibly bend the rigid elongated spacer 11 to fit the step 1d, and there is no risk of installation defects.

[0049] As shown in Figure 6, next, a rehabilitating pipe 3 is constructed (rehabilitating pipe construction process). For example, a self-propelled pipe production device 6 (see Patent Documents 2 and 3) is propelled spirally along the inner circumference of the existing pipe 1, for example from left to right in Figure 6, while a strip-shaped member 5 is supplied to the pipe production device 6. In the pipe production device 6, opposing edges of the spirally wound strip-shaped member 5, which are one turn apart, are joined by a concave-convex fit. As a result, a helical rehabilitating pipe 3 is produced so as to extend forward (upward in Figure 6) as the pipe production device 6 is propelled.

[0050] Within the straight section 1a (excluding the section 1ab near the step) of the existing pipe 1, the rehabilitated straight pipe section 3a is formed by manufacturing the rehabilitated pipe 3 to have a constant cross section. In addition, the protrusion amount of the set screw 16 and the driving amount of the screw anchor 17 are adjusted so that the bottom surface 12b of the spacer body 12 contacts the outer circumferential surface of the rehabilitated straight pipe section 3a.

[0051] As shown by the solid line in Figure 6, when the front extension end 3e of the rehabilitating pipe 3 enters the uneven section 1b from the straight section 1a on the upstream side (left side in Figure 6), the pipe is manufactured so that the circumferential length of the front extension end 3e decreases. This results in the formation of an in-uneven rehabilitating pipe section 3b whose diameter decreases toward the step 1d. At this time, the pipe is manufactured so that the front extension end 3e passes inside the pipe (lower in Figure 6) than the irregular spacer 20. The front extension end 3e may also be pressed against the irregular spacer 20 from below. This applies a downward force to the front extension end 3e toward the inside of the pipe (downward in Figure 6) due to the tension of the irregular spacer 20. This ensures that the front extension end 3e is reduced in diameter when manufactured. As a result, the pipe can be manufactured so that the front extension end 3e passes under the step 1d, as shown by the two-dot chain line in Figure 6. That is, it is possible to prevent the front extension end 3e from hitting the step 1d, which would make it impossible to manufacture the pipe.

[0052] When the front end 3e of the rehabilitating pipe 3 passes through the step 1d and enters the step vicinity 1ad, the circumferential length of the front end 3e is increased (see Figure 1), thereby producing a transitional rehabilitating pipe section 3c whose diameter increases as it moves away from the step 1d. Eventually, the bottom of the extension front end 3e comes into contact with the bottom of the existing pipe 1 and the top of the extension front end 3e comes into contact with the long spacer 11 (see Figure 1), and the pipe is transitioned to pipe production of the rehabilitation straight pipe section 3a, which is further forward in the extension (to the right in Figure 1) than the transition rehabilitation pipe section 3c.

[0053] As shown in Figure 1, after constructing the rehabilitation pipe 3 in this manner, a backfill material 4 is injected into the backfill space 2 (backfilling process). By placing an existing pipe rehabilitation spacer device 10 between the existing pipe 1 and the rehabilitation pipe 3, the backfill space 2 can be secured and the backfill material 4 can be filled into the backfill space 2. The backfilling material 4 is a low viscosity fluid when injected.

[0054] When the rehabilitating pipe 3 attempts to float up due to the buoyancy from the backfill material 4 during injection and before hardening, the rehabilitating pipe 3 is pressed against the existing pipe rehabilitating spacer device 10. This prevents the rehabilitating pipe 3 from floating up. Therefore, the existing pipe rehabilitating spacer device 10 functions to prevent the rehabilitating pipe 3 from floating up due to the buoyancy from the backfill material 4.

[0055] More specifically, in the straight section 1a, the long spacer 11 comes into contact with the upper side or top of the rehabilitating pipe 3, thereby preventing the rehabilitating pipe 3 from floating up. In the uneven area 1b, when the rehabilitating pipe section 3b of the rehabilitating pipe 3 attempts to float up due to the buoyancy of the backfill material 4, the rehabilitating pipe section 3b is pressed against the irregular spacer 20, causing tension corresponding to the buoyancy to act on the irregular spacer 20. The roller chain 25 constituting the irregular spacer 20 has sufficient tensile strength to resist the buoyancy. This prevents the rehabilitating pipe section 3b from floating up. Furthermore, the roller chain 25 has sufficient load-bearing strength to withstand loads such as those caused by the fluid pressure of the backfill material 4, and maintains its original erected state without being crushed. This prevents the rehabilitating pipe 3 from being pressed directly against the step 1d. As a result, it is possible to prevent the formation of depression-like step transfer marks (unevenness transfer marks) on the inner surface of the rehabilitating pipe 3. Prior to the injection of the backfill material 4, a dedicated anti-floating device (not shown) may be installed in the rehabilitating pipe 3 separately from the existing pipe rehabilitating spacer device 10.

[0056] The backfill material 4 is allowed to harden over a period of one to several days after injection. As the backfill material 4 hardens, the existing pipe 1 and the rehabilitating pipe 3 are structurally integrated via the backfill material 4, and a composite pipe is constructed. In this way, the existing pipe 1 is rehabilitated. The rehabilitating pipe 3 may be a self-supporting pipe that has the required strength by itself.

[0057] Next, other embodiments of the present invention will be described. In the following embodiments, the same components as those already described will be denoted by the same reference numerals in the drawings, and the description will be simplified. <Second embodiment (FIG. 7)> As shown in FIG. 7, the pipe axis of an existing pipe 1 may be bent or curved. In FIG. 7, the pipe axes of two straight sections 1a consisting of two straight pipe bodies 1p form an angle with each other, and a bent section 1c (a section near the unevenness including the uneven section) is formed between these straight sections 1a. An irregular spacer 20 in the form of a strip made of a roller chain 22 is provided on the upper side or top of the bent section 1c (the front side of the paper in FIG. 7). The irregular spacer 20 is stretched between the ends of elongated spacers 11 provided on each of the two straight sections 1a. In a plan view, the irregular spacer 20 extends obliquely relative to each elongated spacer 11. By using the strip-shaped irregular spacer 20, the existing pipe rehabilitating spacer device 10 can be reliably installed without any installation defects even at the bend 1c.

[0058] <Third embodiment (FIG. 8)> As shown in Fig. 8, an existing pipe rehabilitating spacer device 10 may be provided on the side of an existing pipe 1. In Fig. 8, an existing pipe rehabilitating spacer device 10 is provided on each side in the pipe diameter direction of an existing pipe 1 having a bent portion 1c. Long spacers 11 are installed on both side in the pipe diameter direction of straight portions 1a on both sides in the pipe axial direction, sandwiching the bent portion 1c. The long spacers 11 make it possible to secure a backfill space 2 between the inner periphery of the straight portion 1a and the side portions of the outer periphery of the rehabilitating pipe 3.

[0059] An irregular spacer 20A made of a roller chain 22 is provided on a side portion 1ca on the inner side of the bent portion 1c. An irregular spacer 20B made of a roller chain 22 is provided on a side portion 1cb on the outer side of the bent portion 1c. The rotation axes of the rollers 25 of these irregular spacers 20A, 20B are oriented in the vertical direction (the direction perpendicular to the paper surface in FIG. 8) and are aligned along the circumferential direction of the pipe. This allows each irregular spacer 20A, 20B to deform to match the curve of the bent portion 1c.

[0060] Specifically, the irregular spacer 20A on the inner periphery is bent to fit the inner periphery side portion 1ca by being applied to the inner periphery side portion 1ca. Both ends of the irregular spacer 20A are connected to the inner periphery elongated spacer 11. The irregular spacer 20B on the outer periphery side portion 1cb extends straight with almost no slack along the outer periphery side portion 1cb. Both ends of the irregular spacer 20B are connected to the outer periphery elongated spacer 11. These irregular spacers 20A, 20B ensure a backfill space 2 between the inner periphery of the bent portion 1c and the side portions of the outer periphery of the rehabilitating pipe 3.

[0061] <Fourth embodiment (FIGS. 9 and 10)> As shown in Fig. 9, in an existing pipe rehabilitating spacer device 10D according to a fourth embodiment of the present invention, an irregular spacer 20D includes one or more housings 30 in addition to a roller chain 22 (a string of chains). As shown in Fig. 10(a), the housing 30 is formed in the shape of a square tube with a U-shaped (C-shaped) cross section, for example. Both ends of the housing 30 in the longitudinal direction (the direction perpendicular to the paper surface in Fig. 10(a)) are open. An opening 31 is formed in the wall of the housing 30 facing the inside of the pipe (the lower side in Fig. 10(a)). The housing 30 is made of a metal such as steel.

[0062] Preferably, the housing 30 has the same cross-sectional shape and is made of the same material as the spacer body 12 (see FIG. 3(d)) of the elongated spacer 11. The length of the housing 30 is shorter than the length of the spacer body 12. This allows the spacer body 12 to be used as the housing 30 by cutting it short.

[0063] 10(b), the housing 30 may be formed in a cylindrical shape with a closed ring-shaped rectangular cross section without the opening 31. In this case, it is preferable that the spacer body 12 also has the same closed ring-shaped rectangular cross section.

[0064] 9, a plurality of housings 30 are arranged in a row. The roller chain 22 is passed through the interiors of the row of housings 30. Therefore, the irregular spacer 20D can be deformed by bending between the adjacent housings 30. In the existing pipe rehabilitating spacer device 10D, the cross-sectional area of ​​the irregular spacer 20D can be increased by the amount of the housing 30. Also, the housing 30 can protect the roller chain 22. Furthermore, the strength of the irregular spacer 20D can be increased.

[0065] <Fifth embodiment (FIG. 11)> 11, in an existing pipe rehabilitation spacer device 10E according to a fifth embodiment of the present invention, a strip-shaped irregular spacer 20E made of a roller chain 22 extends not only in the uneven portion 1b of the existing pipe 1 but also from the straight portion 1a to the uneven portion 1b. Preferably, the irregular spacer 20E extends over the entire axial direction of the existing pipe 1. The irregular spacer 20E is fixed to the existing pipe 1 via screw anchors 28 (fixing means) provided at intervals in the axial direction of the existing pipe 1.

[0066] The portion 29 arranged in the linear portion 1a of the irregular spacer 20E constitutes an elongated spacer. In other words, the elongated spacer 29 in the existing pipe rehabilitating spacer device 10E is strip-shaped and can change its shape. In the existing pipe rehabilitating spacer device 10E, the rigid elongated spacer 11 can be omitted.

[0067] Sixth Embodiment (FIGS. 12 and 13) As shown in FIG. 12, in an existing pipe rehabilitating spacer device 10F according to a sixth embodiment of the present invention, an irregular spacer 20F includes a mass 40, i.e., a mass-shaped irregular spacer, in addition to a roller chain 22 (strip), which is a strip-shaped irregular spacer. The mass 40 is a hardened hardening viscous material 49, and has a required compressive strength. Preferably, the hardening viscous material 49 is made of a high-viscosity, fast-drying mortar, and has a higher hardening start viscosity (i.e., initial viscosity) and hardening speed than the backfill material 4. The unhardened hardening viscous material 49 can freely change shape depending on the surface shape of the unevenness-proximate portion 1b, including the step 1d. The hardening time of the hardening viscous material 49 is preferably several minutes to several hours.

[0068] As shown in Figure 12, the hardening viscous material 49 and hence the mass 40 are placed in close contact with the unevenness vicinity 1b. Preferably, the mass 40 is placed in close contact from the step vicinity 1ba to the step 1d. The thickness of the mass 40 in the pipe diameter direction (vertical direction) preferably increases as it approaches the step 1d. The thickness of the mass 40 in the pipe diameter direction (vertical direction) immediately adjacent to the step 1d is preferably approximately equal to the height of the step 1d, and the mass 40 covers the entire surface of the step 1d.

[0069] As shown in Figure 13(a), the hardening viscous material 49 and therefore the mass 40 form an arc shape along the circumferential direction of the pipe in the upper half of the unevenness-proximal portion 1b. As a result, the mass 40 covers a wide area of ​​the step 1d in the circumferential direction of the pipe. As shown in Figure 12, the mass 40 fills the recessed corner 1g formed by the step-proximal portion 1ba and the step 1d. As a result, the unevenness caused by the step 1d is leveled.

[0070] As shown in Figures 12 and 13(b), a roller chain 22 is installed on the inner surface of the mass 40 facing the inside of the pipe. As shown in Figures 12 and 13(c), the roller chain 22 is interposed between the mass 40 and the unevenness-proximate portion 1b of the rehabilitating pipe 3. In addition, the mass 40 is interposed between the roller chain 22 and the unevenness-proximate portion 1b.

[0071] 13(a), prior to the construction of the rehabilitating pipe 3, a hardening viscous material 49 is rubbed against the unevenness-proximate portion 1b. Preferably, the hardening viscous material 49 is filled into the recessed portion 1g of the inside corner. The hardening viscous material 49 hardens in a short time after being rubbed, and becomes a mass 40 .

[0072] Next, as shown in FIG. 13(b), a roller chain 22 is laid over the hardening viscous body 49 and the inner surface of the mass 40 facing the inside of the tube. As shown in Figure 12, an end of the roller chain 22 is connected to a long spacer 11 that is separately installed in the straight section 1a. This allows the end of the roller chain 22 to be fixed to the existing pipe 1 via the long spacer 11.

[0073] Thereafter, as shown in Figure 13(c), a rehabilitating pipe 3 is constructed within the existing pipe 1. Because the hardening viscous material 49 and, ultimately, the mass 40 smooth out the unevenness of the unevenness-proximate portion 1b, it is possible to easily manufacture the rehabilitating pipe 3 in the unevenness-proximate portion 1b, i.e., the rehabilitating pipe portion 3b within the unevenness. By interposing a roller chain 22 between the rehabilitating pipe 3 and the mass 40, it is possible to secure a backfill space 2 of a size corresponding to the thickness of the roller chain 22.

[0074] As shown in Figures 12 and 13(d), after the rehabilitating pipe 3 is constructed, the backfill space 2 is filled with the backfill material 4. At this time, the mass 40 and the roller chain 22 apply buoyancy to the rehabilitating pipe section 3b within the unevenness, thereby reliably preventing the rehabilitating pipe section 3b from floating up. Furthermore, by supporting the roller chain 22 with the mass 40, it is possible to prevent the roller chain 22 from deforming toward the unevenness-proximate portion 1b and, ultimately, the step 1d. This reliably prevents the formation of unevenness transfer marks, such as step transfer marks, on the rehabilitating pipe 3. Since the inside corner recess 1g is filled in advance with the hardening viscous material 49 and eventually the mass 40, it is possible to prevent a void (a space where the back-filling material 4 has not been poured) from being formed in the inside corner recess 1g.

[0075] Seventh Embodiment (FIGS. 14 and 15) As shown in Fig. 14, in an existing pipe rehabilitating spacer device 10G according to the seventh embodiment of the present invention, similar to the sixth embodiment (Figs. 12 and 13), an irregular spacer 20G includes a roller chain 22 (a strip-shaped irregular spacer) and a mass 40 (a mass-shaped irregular spacer). Furthermore, a housing 30 similar to that of the fourth embodiment (Figs. 9 and 10) is provided on the outer periphery of the roller chain 22. A plurality of housings 30 are arranged in a line, and the roller chain 22 is passed through these housings 30.

[0076] As shown in Figure 15(a), the surface of the casing 30 facing the outside of the pipe (upper side in the figure) is in contact with the mass 40. As shown in Figure 15(b), the surface of the casing 30 facing the inside of the pipe (lower side in the figure) is in contact with the top of the rehabilitation pipe 3.

[0077] In the seventh embodiment, prior to the construction of the rehabilitating pipe 3, a hardening viscous material 49 is rubbed against the unevenness-proximate portion 1b as shown in Fig. 15(a). A roller chain 22 with a housing 30 is installed on the inner surface of the hardening viscous material 49 and, consequently, the mass 40. The housing 30 prevents the roller chain 22 from sinking into the hardening viscous material 49.

[0078] Next, as shown in Figure 15(b), a rehabilitating pipe 3 is constructed. A strip-shaped irregular spacer consisting of a housing 30 and a roller chain 22 is interposed between the rehabilitating pipe section 3b of the rehabilitating pipe 3 and the mass 40, thereby ensuring a backfill space 2. Because the size of the backfill space 2 depends on the height of the housing 30, it is possible to make the backfill space 2 larger than when the strip-shaped spacer is composed only of the roller chain 22. This allows the backfill material 4 to be reliably filled between the rehabilitating pipe section 3b of the rehabilitating pipe 3 and the mass 40 in the subsequent backfilling process, as shown in Figure 15(c).

[0079] Eighth embodiment (FIGS. 16 and 17) 16, in an existing pipe rehabilitating spacer device 10H according to the eighth embodiment of the present invention, an irregular spacer 20H is composed only of a mass 40 (a mass-like irregular spacer) made of a hardening viscous material 49, and does not include a strip-like irregular spacer such as a roller chain 25. As shown in FIGS. 16 and 17(a), the hardening viscous material 49 and hence the mass 40 include a base portion 41 and a receiving protrusion 42.

[0080] As shown in FIG. 16, the base portion 41 is installed in close contact with the unevenness-proximal portion 1b so as to fill the inside corner recess 1g. The thickness of the base portion 41 in the pipe diameter direction (vertical direction) increases as it approaches the step 1d. The thickness of the base portion 41 in the pipe diameter direction (vertical direction) immediately adjacent to the step 1d is preferably approximately equal to the height of the step 1d, and the base portion 41 covers the entire surface of the step 1d. As shown in FIG. 17(a), the base portion 41 is arc-shaped along the pipe circumferential direction of the upper half of the unevenness-proximal portion 1b. As a result, the base portion 41 covers a wide range of the step 1d in the pipe circumferential direction.

[0081] 16 and 17(a), a receiving protrusion 42 is integrally formed in the center of the base portion 41 in the circumferential direction of the pipe. The receiving protrusion 42 protrudes from the base portion 41 toward the inside of the pipe (downward in FIG. 17(a)), and extends over almost the entire area of ​​the base portion 41 in the axial direction of the pipe (the direction perpendicular to the plane of FIG. 17(a)). As shown in FIG. 17(a), the width of the receiving protrusion 42 in the circumferential direction of the pipe is smaller than the width of the base portion 41 in the circumferential direction of the pipe.

[0082] As shown in Figure 17(b), the end of the receiving portion 42 facing the inside of the pipe abuts against the inland rehabilitating pipe portion 3b of the rehabilitating pipe 3. Preferably, as shown in Figure 16, most of the extending portion of the receiving portion 42 abuts against the inland rehabilitating pipe portion 3b.

[0083] In the eighth embodiment, prior to the construction of the rehabilitating pipe 3, as shown in Fig. 17(a), a hardening viscous material 49 is rubbed against the unevenness vicinity 1b. At this time, a base portion 41 and a receiving protrusion 42 are formed. Next, as shown in FIG. 17(b), a rehabilitating pipe 3 is constructed. In the unevenness-proximal portion 1b, the top of the rehabilitating pipe section 3b of the rehabilitating pipe 3 abuts against the receiving protrusion 42 of the mass 40. A backfilling space 2 equal to the height of the receiving protrusion 42 can be secured between the base 41 and the unevenness-proximal rehabilitating pipe section 3b. This allows the backfilling material 4 to be reliably filled between the unevenness-proximal rehabilitating pipe section 3b and the base 41 in the subsequent backfilling process, as shown in FIG. 17(c). Furthermore, the mass 40 applies buoyancy to the rehabilitating pipe 3, preventing the rehabilitating pipe 3 from floating up. Furthermore, the mass 40 reliably prevents the formation of step transfer marks (unevenness transfer marks) on the rehabilitating pipe 3.

[0084] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention. For example, the strip-shaped irregular spacer is not limited to the roller chain 22, but may be a ball chain or a general chain made up of elliptical ring-shaped chain bodies (chain elements). For each pipe 1p of the existing pipe 1, a strip-like irregular spacer such as a roller chain 22 having approximately the same length as the pipe 1p may be installed. An existing pipe rehabilitation spacer device may be installed in the lower half or bottom of the existing pipe 1. An irregular spacer may be installed in the vicinity of the unevenness, including the unevenness in the lower half or bottom of the existing pipe 1.

[0085] Two or more of the above-described embodiments may be combined with each other. For example, in the fifth embodiment (FIG. 11) in which the roller chain 22 (strand) extends from the straight portion 1a of the existing pipe 1 to the uneven portion 1b, the mass 40 made of the hardening viscous material 49 of the sixth embodiment (FIGS. 12 and 13) may be installed in close contact with the uneven portion 1b. In addition, the housing 30 of the fourth embodiment (Figures 9 to 10) may be provided on the outer periphery of at least a portion of the roller chain 22 (strand) extending from the straight section 1a to the uneven section 1b in the fifth embodiment (Figure 11) (particularly the outer periphery of the portion installed in the uneven section 1b). The curved portion 1c (1ca, 1cb) of the second embodiment (Figure 7) or the third embodiment (Figure 8) may be provided with a hardening viscous body 40 (lump) of the sixth embodiment (Figures 12 to 13) or the seventh embodiment (Figure 14). [Industrial Applicability]

[0086] The present invention can be applied to, for example, a technology for rehabilitating aged sewer pipes. [Explanation of symbols]

[0087] 1 Existing pipes 1a Straight section 1b Uneven areas 1c Bends (areas near uneven ground, including uneven areas) 1d Steps (uneven areas) 2 Backfill space 3 Rehabilitation pipe 3b Unland Rehabilitation Pipe Section 4 Backfill material 5. Belt-shaped member 6. Self-propelled pipe making equipment 10. Spacer device for rehabilitating existing pipes 10D~10H Spacer device for rehabilitating existing pipes 11 Long spacer 12 Spacer body 13 Attachment means 16 Set screw (protruding part) 17 Screw anchor (fixing member) 20 Irregular Spacer 20D~20H irregular spacer 21 Chain body 22 Roller chain (strand, chain) 25 Laura L 25 Rotation axis 29 Parts that make up the long spacer 30 Case 40 lumps 41 Base 42 Receiving protrusion 49 Curing viscous material

Claims

1. A method for rehabilitating an existing pipe, comprising: constructing a rehabilitation pipe in an existing pipe; and then filling a backfill material into a backfill space between the existing pipe and the rehabilitation pipe; Prior to constructing the rehabilitation pipe, a step of installing a long spacer in a linear portion along a pipe axis direction on an inner peripheral surface of the existing pipe, with the longitudinal direction of the spacer facing the pipe axis direction; a step of placing a shape-changeable strip-like or block-like irregular spacer in an area near the unevenness including the unevenness on the inner circumferential surface of the existing pipe; A method for rehabilitating existing pipes, characterized by:

2. A method for rehabilitating an existing pipe as described in claim 1, in which a chain in which adjacent chain bodies arranged in a row as the irregular spacer are connected so that they can be displaced relative to each other is installed in the vicinity of the unevenness with its extension direction aligned with the pipe axis direction.

3. A method for rehabilitating an existing pipe as described in claim 2, in which a roller chain having links arranged in a row and rollers that rotatably connect adjacent links is installed in an area near the unevenness in the upper half or side part of the existing pipe, with the rotation axis of the rollers facing circumferentially around the pipe.

4. The chain is laid from the straight section to the uneven section, The method for rehabilitating an existing pipe according to claim 2, wherein the portion of the chain that is stretched over the straight portion is provided as the elongated spacer.

5. A method for rehabilitating an existing pipe described in any one of claims 2 to 4, wherein a hardening viscous material having a higher hardening initiation viscosity and hardening speed than the backfill material is adhered to the area near the unevenness, and the chain is placed on the inner surface of the hardening viscous material.

6. 2. The method for rehabilitating an existing pipe according to claim 1, wherein the irregular spacer is a hardening viscous material having a hardening initiation viscosity and hardening speed higher than those of the backfill material, and the hardening viscous material is adhered to the vicinity of the unevenness.

7. A method for rehabilitating an existing pipe as described in claim 6, wherein the hardening viscous body has a receiving protrusion that protrudes from a base portion that is in close contact with the uneven area toward the inside of the existing pipe and is capable of abutting the rehabilitated pipe.

8. An existing pipe rehabilitation spacer device that is installed in a backfill space between a rehabilitation pipe constructed in an existing pipe and the existing pipe, a long spacer installed in a linear portion along the pipe axis direction on the inner peripheral surface of the existing pipe, with its longitudinal direction directed in the pipe axis direction; a shape-changeable strip-like or block-like irregular spacer to be installed in the vicinity of the unevenness including the unevenness on the inner circumferential surface of the existing pipe; A spacer device for rehabilitating existing pipes, comprising:

9. 9. The spacer device for rehabilitating an existing pipe according to claim 8, wherein the irregular spacer includes a chain in which adjacent chain members arranged in a row are linked together so as to be displaceable relative to each other.

10. 10. The spacer device for rehabilitating an existing pipe according to claim 9, wherein an end of the chain is connected to the long spacer.

11. 10. The spacer device for rehabilitating an existing pipe according to claim 9, wherein the chain is a roller chain having links arranged in a row and rollers rotatably connecting adjacent links to each other.

12. 10. The spacer device for rehabilitating an existing pipe according to claim 9, wherein the irregular spacer further includes a housing having both longitudinal ends open, and the chain is passed through the interior of the housing.

13. 13. The spacer device for rehabilitating an existing pipe according to claim 12, wherein the elongated spacer includes a spacer body having the same cross-sectional shape and material as the housing.

14. A spacer device for rehabilitating existing pipes as described in any one of claims 9 to 13, wherein the irregular spacer further includes a mass formed by hardening a hardening viscous material having a higher hardening initiation viscosity and hardening speed than the backfill material to be backfilled into the backfill space, the mass being in close contact with the uneven area, and the chain being provided on the inner surface of the mass.

15. The irregular spacer includes a mass formed by hardening a hardening viscous material having a higher hardening initiation viscosity and hardening speed than the backfill material backfilled into the backfill space, and the mass is in close contact with the uneven area.

16. A spacer device for rehabilitating existing pipes as described in claim 15, wherein the mass includes a base portion that is tightly attached to the area near the unevenness, and a receiving protrusion that protrudes from the base portion toward the inside of the existing pipe and is capable of abutting the rehabilitating pipe, and the width of the receiving protrusion along the circumferential direction of the pipe is smaller than the width of the base portion along the circumferential direction of the pipe.

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