Pipe reinforcement method and reinforced pipe

Abstract

To improve earthquake resistance at low cost.SOLUTION: A reinforcement method is a method of reinforcing a pipe conduit composed of a plurality of protective pipes 1 and joints 2 connecting end parts of two adjacent protection pipes 1 out of the plurality of protection pipes 1, comprising a step of attaching a lining pipe 3 integrally formed to a part including the respective end parts of the two protection pipes 1 connected to each other by the joints 2.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a method for reinforcing a pipeline and a reinforced pipeline. [Background technology]

[0002] A pipeline buried in the ground is composed of multiple pipes, each of which has a length of several meters, connected by joints. The joints are formed, for example, by screwing, gluing, welding, plugging, etc. It is known that joints connecting multiple pipes that constitute the pipeline can be detached, bent, pushed in, etc. due to a large earthquake. In addition, the joints are required to have various functions in terms of workability, watertightness, airtightness, temperature expansion and contraction, vibration absorption, etc., and joints of various shapes and structures have been developed and introduced in response to such requirements. For example, joints formed by screwing and gluing have low expansion and contraction and flexibility. For this reason, it has been found that the damage rate of pipelines using such joints is relatively high compared to pipelines using other types of joints.

[0003] Furthermore, if the pipelines in supply facilities such as waterworks and gas are damaged by an earthquake, water, gas, etc. passing through the pipelines may leak. Furthermore, if the pipelines in facilities housing cables used in services such as electricity, communications, and CATV (Community Antenna TeleVision) are damaged by an earthquake, the cables may be damaged and services may be affected. Therefore, in supply facilities such as waterworks and gas, pipes and joints are being replaced with pipes and joints with higher earthquake resistance. In addition, in pipelines in cable housing facilities, new pipes are constructed on the inner surface of deteriorated pipes without excavation, thereby maintaining the quality of the pipelines and improving earthquake resistance (for example, Patent Documents 1 to 3). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 7-178816 [Patent Document 2] JP 2010-74914 A [Patent Document 3] JP 2011-101583 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, although the above-mentioned technology for replacing pipes and joints has the effect of providing high earthquake resistance, it may require high construction costs because it involves excavation work. In addition, the method for replacing pipes and joints generates waste such as removed equipment and excavated soil, which places a burden on the environment. In addition, since there are a huge number of facilities equipped with pipes and joints, it takes a huge amount of time to replace the pipes and joints equipped in all the facilities. Furthermore, in many cases, the replacement of pipes and joints involves road construction, which has the problem of affecting society and the economy due to traffic congestion.

[0006] In addition, in the techniques described in Patent Documents 1 to 3, the entire length of the pipeline is repaired, so a large amount of materials and equipment for new pipes to be constructed on the inside surface of the pipeline is required, which increases construction costs. In addition, space is required on the road near the manhole that is connected to the pipeline to store construction vehicles, equipment, and the like. For this reason, although not as much as open-cut construction, it may cause traffic obstruction on the road. Furthermore, even if only a part of the pipeline is deteriorated, a new pipe is constructed along the entire length of the pipeline, which is inefficient in terms of cost-effectiveness.

[0007] SUMMARY OF THE PRESENT EMBODIMENT In view of the above circumstances, an object of the present invention is to provide a pipeline reinforcement method and a reinforced pipeline that can improve earthquake resistance at low cost. [Means for solving the problem]

[0008] A reinforcement method according to one embodiment is a method for reinforcing a pipeline composed of a plurality of protective pipes and a joint connecting the ends of two adjacent protective pipes among the plurality of protective pipes, and includes a step of attaching a lining pipe that is constructed as an integral part of a portion of the protective pipes, including the ends of each of the two protective pipes that are connected to each other by the joint.

[0009] A reinforced pipeline in one embodiment comprises a plurality of protective pipes, a joint connecting the ends of two adjacent protective pipes among the plurality of protective pipes, and a lining pipe that is integrally formed and attached to a portion of the protective pipes, including the ends of each of the two protective pipes connected to each other by the joint. Effect of the Invention

[0010] According to the present invention, there is provided a pipeline reinforcement method and a reinforced pipeline that can improve earthquake resistance at low cost. [Brief description of the drawings]

[0011] [Figure 1A] FIG. 4 is a cross-sectional view showing an example of a reinforcing pipeline according to the present embodiment. [Figure 1B] 1B is a cross-sectional view of the reinforcing pipe shown in FIG. 1A taken along line AA. [Figure 2A] FIG. 1B is a perspective view of the lining pipe shown in FIG. 1A. [Figure 2B] FIG. 3B is an enlarged view of the end of the lining pipe shown in FIG. 3A. [Figure 2C] FIG. 13 is an enlarged view of an end portion of a modified example of a lining pipe. [Diagram 3] 1B is a cross-sectional view showing a state in which a joint is disengaged in the reinforced pipe shown in FIG. 1A. [Figure 4] 4 is a flowchart showing an example of a method for reinforcing a pipeline according to the present embodiment. [Figure 5A] FIG. 2 is a diagram showing the state in which a lining pipe before hardening is installed inside a protective pipe. [Figure 5B] 5B is a cross-sectional view of the reinforcing pipe shown in FIG. 5A taken along line BB. [Figure 6A] FIG. 2 is a diagram showing a state in which a pressurizing balloon is inflated. [Figure 6B] 6B is a cross-sectional view taken along line CC of the reinforcing pipe shown in FIG. 6A. [Figure 7] 13 is a diagram showing the state in which the pressurizing balloon is inflated and the lining tube is hardened. FIG. [Figure 8] FIG. 11 is a view for explaining a first modified example of the method for reinforcing a pipeline according to the present embodiment. [Figure 9] FIG. 11 is a view for explaining a second modified example of the method for reinforcing a pipeline according to the present embodiment. [Figure 10] FIG. 1 is a cross-sectional view showing an example of a reinforced pipeline lined over its entire length according to the prior art. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0013] <Structure of reinforced pipeline> An example of the configuration of the reinforced pipeline 100 according to the embodiment of the present invention will be described.

[0014] As shown in FIGS. 1A and 1B, the reinforced pipeline 100 includes a plurality of protective pipes 1, a joint 2, and a lining pipe 3.

[0015] The protective pipe 1 is a cylindrical component made of materials such as steel, polyvinyl chloride, etc. The protective pipe 1 is buried underground, and is constructed to house cables used for electricity, communications, CATV, etc.

[0016] The joint 2 connects the ends of two adjacent protective tubes 1 among the multiple protective tubes 1. Specifically, the joint 2 connects the ends of the multiple protective tubes 1 in the extension direction (the axial direction of the cylinder that forms the protective tube 1). By connecting the multiple protective tubes 1 with the joint 2, the multiple protective tubes 1 can accommodate a cable that is longer than a single protective tube 1.

[0017] The lining pipe 3 is formed of a curable resin that is flexible before curing and is cured by a predetermined action. The curable resin may be a thermosetting resin that is cured by heating, an ultraviolet curable resin that is cured by irradiation with ultraviolet rays, or the like. That is, when the curable resin is a thermosetting resin, the predetermined action is heating, and when the curable resin is an ultraviolet curable resin, the predetermined action is irradiation with ultraviolet rays.

[0018] The lining pipe 3 is attached to a part of the protective pipe 1, including the ends of each of the two protective pipes 1 connected to each other by the joints 2, and is configured as one piece. "Configured as one piece" means that the lining pipe 3 is not divided on the opposite side of the joints 2 to the protective pipe 1, but is continuous. The lining pipe 3 is provided on only a part of the inner surface of the protective pipe 1. In other words, the lining pipe 3 is not provided over the entire protective pipe 1 in the extension direction.

[0019] As shown in FIG. 2A, the lining pipe 3 has a cylindrical shape. The end of the lining pipe 3 may be tapered. For example, as shown in FIG. 2B, which is an enlarged view of the area surrounded by the dashed line in FIG. 2A, the inner diameter of the lining pipe 3 may be tapered so that it linearly increases toward the end. Also, as shown in FIG. 2C, the inner diameter of the lining pipe 3 may be tapered so that it exponentially increases toward the end. In this way, by configuring the end of the lining pipe 3 to be tapered, when the cable is drawn into the protective pipe 1 having the lining pipe 3 on its inner surface and when the cable is removed from the protective pipe 1, the cable can smoothly pass near the end of the lining pipe 3 in the protective pipe 1. Accordingly, the operator can easily draw in and remove the cable.

[0020] The length of the lining pipe 3 can be designed so that the continuity of the pipeline formed by the protective pipe 1 and the lining pipe 3 is maintained even if the joint 2 comes off due to the occurrence of an earthquake. As an example, the length of the lining pipe 3 can be designed by the method described in the following document. "Guidelines for Earthquake-Resistant Construction Methods for Waterworks Facilities: Commentary 2009 Edition I General Overview", Japan Water Works Association, pp.87-92, pp.195-197, 2009

[0021] Specifically, the thickness of the surface layer in the soft ground of the alluvial plain is H = 30m, and the shear wave velocity of the surface layer is Vs = 100m / s. In this example, the natural period T G is calculated using equation (1).

[0022]

number

[0023] Furthermore, according to the above literature, the natural period T G Design response spectrum S per unit seismic intensity of L2 ground motion of 1.2 s v The horizontal displacement amplitude U of the L2 design earthquake motion used in the response displacement method is 70 to 100 cm / s. h (X) is calculated using the depth X from the ground surface by equation (2). From equation (2), the displacement amplitude U h At x=0, where (X) is maximum, the displacement amplitude U h (X) is calculated to be 17.0 to 24.3 cm.

[0024]

number

[0025] According to past research and observations, it is known that the effect of the inertial force generated by an earthquake on the protective pipe 1 buried in the ground can be ignored, and the behavior of the protective pipe 1 is governed by ground displacement. It is also known that when the ground displacement exceeds a certain magnitude, slippage occurs between the pipeline and the ground. When ground displacement occurs that can have a non-negligible effect on the pipeline, the joint 2 connecting the protective pipes 1 may come off from the protective pipe 1, as shown in FIG. 3. In this case, the distance La between the center position of the joint 2 and the end of the protective pipe 1 is a maximum of 243 mm. Therefore, in order for the pipeline to protect the entire contents such as cables even if the joint 2 comes off, the length Lb of the lining pipe 3 from the position corresponding to the center position of the joint 2 to one end must be at least 243 mm. As an example, if the first digit is rounded up to take into account construction errors and the like, and the safety factor is set to, for example, 2, the length from one end of the lining pipe 3 to the other end, i.e., the total length Lb×2 of the lining pipe 3, can be set to 250 mm×2=500 mm. The safety factor may be appropriately designed by the operator or other person who owns the reinforced pipeline.

[0026] <Method of reinforcing pipes> Here, the steps of reinforcing a pipeline according to this embodiment will be described with reference to Fig. 4. Fig. 4 is a flow chart showing an example of the steps of reinforcing a pipeline according to this embodiment. The steps of reinforcing a pipeline described with reference to Fig. 4 correspond to an example of a method of reinforcing a pipeline according to this embodiment. This reinforcement method starts from a state in which protective pipes 1 have already been buried in the ground and joints 2 are connecting protective pipes 1 to each other.

[0027] The reinforcing method according to this embodiment includes a step of attaching a lining pipe 3 that is configured as one unit to a part of the protective pipe 1, including each end of two protective pipes 1 that are connected to each other by joints 2. Specifically, the step of attaching the lining pipe 3 includes a step of attaching the lining pipe 3 from the inner surface of the end side of one of the two protective pipes 1 to the inner surface of the end side of the other protective pipe 1 that faces the one protective pipe 1. Details of this will be described below.

[0028] In step S1, the inside of the protective tube 1 is cleaned by using a water jet or the like.

[0029] In step S2, as shown in Figures 5A and 5B, the lining pipe 3 before hardening is installed in a part of the inside of the protective pipe 1, including the ends of each of the two protective pipes 1 connected by the joints 2. At this time, as shown in Figure 5A, an imaging device 11 such as a pipe camera may be pulled inside the protective pipe 1. In such a configuration, the lining pipe 3 may be installed in a predetermined position by having the towing device tow the lining pipe 3 while grasping the position of the lining pipe 3 from a captured image including an image of the lining pipe 3 captured by the imaging device 11.

[0030] In step S3, the pressurizing balloon 12 is drawn into the lining pipe 3 formed from the uncured curable resin, which was placed at a predetermined position in step S2. Note that the pressurizing balloon 12 may be drawn into the lining pipe 3 prior to step S2, and the lining pipe 3 with the pressurizing balloon 12 drawn therein may be placed at a predetermined position in step S2.

[0031] 6A and 6B, in step S4, gas is supplied to the pressurizing balloon 12 by the pressure supply hose 13 to inflate the pressurizing balloon 12, thereby expanding the diameter of the lining pipe 3. As a result, the lining pipe 3 with the expanded diameter is pressed against the inner surface of the protective pipe 1.

[0032] In step S5, the hardening resin forming the lining pipe 3 is hardened.

[0033] As an example of steps S4 and S5, in a configuration in which the curable resin is a thermosetting resin, the pressurizing balloon 12 is filled with hot water or steam to expand the pressurizing balloon 12 and expand the diameter of the lining pipe 3. At this time, the thermosetting resin forming the lining pipe 3 is cured by heating with the hot water or steam filling the inside of the pressurizing balloon 12. The thermosetting resin forming the lining pipe 3 is cured by being heated for a predetermined time. In this example, steps S4 and S5 are executed at the same timing.

[0034] As another example of steps S4 and S5, in a configuration in which the curable resin is an ultraviolet curable resin, the pressurizing balloon 12 is transparent. The transparent pressurizing balloon 12 arranged in the lining pipe is filled with air, and the pressurizing balloon 12 is expanded to expand the diameter of the lining pipe 3. At this time, as shown in FIG. 7, the ultraviolet curable resin forming the lining pipe 3 is cured by ultraviolet light irradiated from an ultraviolet lamp 15 installed inside the pressurizing balloon 12. The ultraviolet curable resin forming the lining pipe 3 is cured by being irradiated with ultraviolet light for a predetermined time. The ultraviolet lamp 15 can irradiate ultraviolet light by being supplied with power through a power cable 16. In this example, steps S4 and S5 may be performed at the same time, or step S5 may be performed after step S4.

[0035] In step S6, the gas in the pressurizing balloon 12 is removed by the decompression hose 14, thereby reducing the pressure in the pressurizing balloon 12.

[0036] In step S7, the pressurizing balloon 12 that has deflated due to the reduction in pressure in step S6 is removed from inside the protective tube 1.

[0037] As a result of the above, the lining pipe 3, which is constructed as one unit, is attached to a part of the protective pipe 1, including each end of the two protective pipes 1 connected to each other by the joints 2.

[0038] <First modified example of the method for reinforcing the pipeline> In the above steps S1 to S7, the process of attaching the lining pipe 3 to a position on the inner surface of the pipeline corresponding to one joint 2 has been described, but the lining pipe 3 may be attached to each of multiple joints 2 at the same time.

[0039] 8, the step of drawing the uncured lining pipe 3 into the inside of the protective pipe 1 may include a step of drawing a plurality of lining pipes 3, the ends of which are connected to each other using a connecting member 17, into the inside of the protective pipe 1. The connecting member 17 may be, for example, a string.

[0040] <Second modified example of the method for reinforcing the pipeline> 9, the pressurizing balloon 18 may be installed over the entire length of a pipeline formed by a plurality of protective pipes 1 connected by joints 2. In such a configuration, the pressurizing balloon 18 is inflated to expand the diameter of each of the plurality of lining pipes 3. As a result, each of the plurality of lining pipes 3 with an expanded diameter is pressed against the inner surface of the protective pipe 1. Then, the curable resin forming each of the plurality of lining pipes 3 is cured.

[0041] <Third modified example of the pipe reinforcement method> The lining pipe 3 is expected to be attached to the protective pipe 1 by friction between the lining pipe 3 and the inner surface of the protective pipe 1. However, the lining pipe 3 may be bonded to the inner surface of the protective pipe 1 by an adhesive so that the lining pipe 3 is attached to the protective pipe 1 more firmly. For example, in the above-mentioned step S2, a bag that breaks when the pressure becomes higher than a predetermined value may be attached to the outside of the lining pipe 3 before curing, which contains the adhesive. As a result, in step S4, the bag breaks and the contained adhesive is applied to the outer surface of the lining pipe 3 and the inner surface of the protective pipe 1. Therefore, the lining pipe 3 is attached to the protective pipe 1 more firmly by the adhesive. Note that a bag that breaks when the temperature becomes higher than a predetermined value may be used instead of the bag that breaks when the pressure becomes higher than a predetermined value. In such a configuration, for example, the bag breaks and the contained adhesive is applied to the outer surface of the lining pipe 3 and the inner surface of the protective pipe 1 by the heat used in the first example of steps S4 and S5.

[0042] <Experimental Results> If the protective tube 1 is displaced only in the extension direction due to ground vibrations caused by an earthquake, the displacement of the protective tube 1 will not apply much force to the cable. Therefore, the services provided using the cable will not be affected much. However, in reality, when an earthquake occurs, the ground will continuously vibrate in various three-dimensional directions. For this reason, the joint 2 may come off the protective tube 1, causing repeated collisions between the joint 2 and the protective tube 1, or the protective tube 1 may be displaced in a direction perpendicular to the extension direction, applying a shear force to the cable housed in the protective tube 1.

[0043] The following literature describes the results of analysis and experiments that reproduced a case in which the 2007 Chuetsu-oki earthquake caused the interruption of services provided using cables housed in pipelines. Koji Tanaka et al., "Evaluation method for cable protection effect of lining-reinforced communication pipes during earthquakes," Journal of the Japan Society of Civil Engineers, Vol. 68, No. 4, I_959-I_968, 2012

[0044] In the experiment in the above-mentioned document, a test specimen consisting of a protective pipe 1 and a joint 2 without a lining pipe 3 and a test specimen consisting of a protective pipe 1 and a joint 2 each with a plurality of types of lining pipes 3 were used. The protective pipe 1 of these test specimens was forcibly pulled out to displace the joint 2 by an amount equivalent to the amount of separation, and then the protective pipe 1 was pushed in the opposite direction to the direction in which it was pulled out, and this was repeated. As a result, in the test specimen consisting of a protective pipe 1 and a joint 2 without a lining pipe 3, the end of the protective pipe 1 from which the joint 2 had been separated was deformed by repeatedly colliding with the joint 2, and the cable inside was sometimes damaged. In contrast, in the test specimen consisting of a protective pipe 1 and a joint 2 with a lining pipe 3, the surface of the lining pipe 3 was scratched, the protective pipe 1 was bitten into the lining pipe 3, and further, depending on the type of the lining pipe 3, the lining pipe 3 was sometimes broken. However, the cable housed in the protective pipe 1 with the lining pipe 3 was not damaged. This is thought to be because, even if the joint 2 detaches from the protective pipe 1, the central axis of the pipeline is not shifted due to the lining pipe 3 provided on the protective pipe 1, and although the protective pipe 1 and the joint 2 may collide against each other in the extension direction, collision in a direction perpendicular to the extension direction is suppressed.

[0045] As described above, the method for reinforcing a pipeline according to the present embodiment is a method for reinforcing a pipeline that is configured by a plurality of protective pipes 1 and joints 2 that connect the ends of two adjacent protective pipes 1 among the plurality of protective pipes 1, and includes a step of attaching a lining pipe 3 that is configured as one unit to a part of the protective pipe 1, including the ends of each of the two protective pipes 1 that are connected to each other by the joints 2. This makes it possible to reinforce the pipeline at a low cost so as to improve earthquake resistance. Specifically, the method for reinforcing a pipeline according to the present embodiment allows the lining pipes 3 to be attached at regular intervals. Therefore, as shown in FIG. 10, construction costs can be reduced compared to the case where the lining pipe 93 is attached over the entire length of the pipeline 900 that is configured by the protective pipes 91 connected by the joints 92. Furthermore, since the lining pipe 3 is attached near the joints 2 that are likely to come off from the protective pipe 1 due to the occurrence of an earthquake, the continuity of the pipeline can be maintained even if the joints 2 come off from the protective pipe 1. This makes it possible to suppress the impact on services provided using the cables and the like housed in the protective pipe 1.

[0046] Furthermore, in the pipeline reinforcement method according to this embodiment, the step of attaching the lining pipe 3 includes a step of attaching the lining pipe 3 that is continuous from the inner surface of the end side of one of the two protective pipes 1 to the inner surface of the end side of the other protective pipe 1 that faces the one protective pipe 1 at the end side. As a result, even if the joint 2 comes off the protective pipe 1 due to the occurrence of an earthquake, the lining pipe 3 is unlikely to come off the protective pipe 1, and therefore the continuity of the pipeline can be more reliably maintained.

[0047] Furthermore, in the pipeline reinforcement method according to this embodiment, the lining pipe 3 is made of a hardening resin that is flexible before hardening and is hardened by a predetermined action. This allows the lining pipe 3 to be easily drawn into the protective pipe 1, and the lining pipe 3 can be formed into a shape that matches the shape of the inner surface of the protective pipe 1. This allows the lining pipe 3 to be securely attached to the protective pipe 1, and therefore the continuity of the pipeline can be more reliably maintained.

[0048] Furthermore, in the pipeline reinforcement method according to this embodiment, the step of drawing the uncured lining pipe 3 into the protective pipe 1 includes a step of drawing a plurality of lining pipes 3, the ends of which are connected together using a connecting member 17, into the protective pipe 1. This allows the lining pipes 3 to be attached more efficiently than when the lining pipes 3 are attached one by one to each of the plurality of joints 2 connecting the ends of the protective pipes 1 together.

[0049] Moreover, in the pipeline reinforcement method according to this embodiment, the pressurizing balloon 12 is installed over the entire length of the pipeline formed by a plurality of protective pipes 1 connected by joints 2. This makes it possible to enlarge the diameters of the plurality of lining pipes 3 more efficiently than in the case where a pressurizing balloon 12 is installed one by one corresponding to each of the plurality of lining pipes 3.

[0050] Moreover, the reinforced pipeline 100 according to this embodiment includes a plurality of protective pipes 1, a joint 2 that connects ends of two adjacent protective pipes 1 among the plurality of protective pipes 1, and a lining pipe 3 that is integrally formed with a portion of the protective pipe 1 including each end of the two protective pipes 1 that are connected to each other by the joint 2. This enables the pipeline to have improved earthquake resistance at low cost.

[0051] The present invention is not limited to the above-mentioned embodiment and modified examples. For example, the above-mentioned various processes may be executed not only in chronological order as described, but also in parallel or individually depending on the processing capacity of the device executing the processes or as necessary. In addition, appropriate modifications are possible within the scope of the present invention.

[0052] Although the above-mentioned embodiment has been described as a representative example, it is obvious to those skilled in the art that many modifications and substitutions can be made within the spirit and scope of the present disclosure. Therefore, the present invention should not be interpreted as being limited by the above-mentioned embodiment, and various modifications and changes are possible without departing from the scope of the claims. [Explanation of symbols]

[0053] 1 Protection tube 2. Joints 3. Lining pipe 11 Imaging device 12 Pressure balloon 13 Pressure supply hose 14 Pressure Reducing Hose 15. Ultraviolet Lamp 16 Power Cable 17 Connecting members 18 Pressure balloon 100 Reinforced Pipe

Claims

1. A method for reinforcing a pipeline including a plurality of protective pipes and a joint for connecting ends of two adjacent protective pipes among the plurality of protective pipes, comprising the steps of: The method includes a step of attaching a lining pipe that is integrally formed to a portion of the protective pipe, the portion including the ends of the two protective pipes that are connected to each other by the joints; A reinforcement method, wherein the step of attaching the lining pipes includes a step of pulling a plurality of lining pipes, the ends of which are connected together using connecting members, into the inside of the protective pipe.

2. The reinforcement method described in claim 1, wherein the step of attaching the lining pipe includes a step of attaching the lining pipe from the inner surface of the end side of one of the two protective pipes to the inner surface of the end side of the other protective pipe that faces the one of the two protective pipes at the end side.

3. 3. The reinforcing method according to claim 1, wherein the lining pipe is made of a hardening resin which is flexible before hardening and which is hardened by a predetermined action.

4. the curable resin is a thermosetting resin, The step of drawing the lining pipe into the inside of the protective pipe is a step of drawing the lining pipe before hardening into the inside of the protective pipe, The step of attaching the lining pipe further comprises: placing the lining pipe before hardening in a portion of the protective pipe including each end of the two protective pipes; A step of expanding a diameter of the lining pipe by filling the inside of a pressurizing balloon arranged in the lining pipe with hot water or steam, thereby expanding the pressurizing balloon; hardening the thermosetting resin forming the lining pipe with the hot water or steam; removing the pressurizing balloon from inside the protective tube; The reinforcing method according to claim 3 , comprising:

5. the curable resin is an ultraviolet curable resin, The step of drawing the lining pipe into the inside of the protective pipe is a step of drawing the lining pipe before hardening into the inside of the protective pipe, The step of attaching the lining pipe further comprises: placing the lining pipe before hardening in a portion of the protective pipe including each end of the two protective pipes; A step of expanding a diameter of the lining pipe by filling the inside of a transparent pressurizing balloon disposed in the lining pipe with air and expanding the pressurizing balloon; curing the ultraviolet curing resin forming the lining tube with ultraviolet light irradiated from an ultraviolet lamp installed inside the pressurizing balloon; removing the pressurizing balloon from inside the protective tube; The reinforcing method according to claim 3 , comprising:

6. A reinforcement method as described in claim 4 or 5, wherein the pressurizing balloon is installed over the entire length of the pipeline formed by the multiple protective tubes connected by the joints.

7. A method for reinforcing a pipeline that is composed of a plurality of protective tubes and a joint that connects ends of two adjacent protective tubes among the plurality of protective tubes, comprising: A reinforcement method comprising the step of attaching a lining tube which is integrally formed with a portion of the protective tube, including the respective ends of the two protective tubes which are connected to each other by the joints, and whose ends are formed in a tapered shape.

8. A plurality of protective tubes; a joint for connecting ends of two adjacent protective tubes among the plurality of protective tubes; A lining tube is attached to a portion of the protective tube, including the ends of the two protective tubes connected to each other by the joints, and is integrally formed, with the ends being tapered; A reinforced pipeline comprising:

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