Method for laying new pipe

Abstract

To provide a laying method of a new pipe capable of improving corrosion resistance of the new pipe and shortening a construction period.SOLUTION: The method includes an excavated ditch formation step of forming an excavated ditch 70 in the ground, a temporary pipe installation step of installing a temporary pipe 12 in the excavated ditch, a main pipe member introduction step of introducing a tubular main pipe member 18 made of an uncured photocurable or thermosetting resin or a flattened thermoplastic resin into the temporary pipe, and a step of supplying compressed fluid or steam into the main pipe member to expand the diameter of the main pipe member. The laying method of the new pipe includes a main pipe member diameter expanding process for bringing the main pipe member into close contact with the inner peripheral surface of the temporary pipe, and a main pipe member hardening process for hardening the main pipe member by light irradiation, heating or cooling, and the temporary pipe has strength capable of regulating the diameter expansion of the main pipe member in the main pipe member diameter expanding process.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a method for laying a new pipe, and more particularly to a method for laying a new pipe in an excavation trench formed by excavating the ground. [Background technology]

[0002] Conventionally, when laying new sewer pipes, the ground is first excavated, a manhole is installed at a designated location along the sewer pipe's route, and the new concrete pipe is then connected to the manhole. This new pipe is installed using the so-called cut-and-cover method, which involves excavating the ground from above ground. Furthermore, because new concrete pipes are heavy, shorter new pipes are joined together to form a single sewer pipe connecting two adjacent manholes.

[0003] The work of joining new pipes together in an excavation trench is inefficient due to the limited work space, which causes the construction period to be extended. In order to improve work efficiency, Patent Document 1 discloses an open-cut construction method that reduces the work of joining new pipes together in an excavation trench by repeating the process of joining two new pipes on the ground and then lowering the two joined new pipes into the excavation trench. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-65250 Summary of the Invention [Problem to be solved by the invention]

[0005] As mentioned above, installing a new sewer pipe using the cut-and-cover method requires first digging the ground to form a trench, then joining a short concrete pipe introduced into the trench and connecting two manholes with the concrete pipe. Therefore, if the laying distance is long, for example, if the distance between manholes to be installed is long, the work of joining the new pipes and inspecting the connection status increases, lengthening the construction period and the period of traffic restrictions.

[0006] Furthermore, while concrete sewer pipes are alkaline, the environment inside them is highly acidic, which can cause corrosion inside the pipes over many years of use, resulting in premature deterioration. Concrete sewer pipes have a relatively large surface roughness, and as corrosion increases the surface roughness, the flow of sewage becomes more difficult. Therefore, there is a need to improve the corrosion resistance of newly constructed sewer pipes to prevent deterioration due to corrosion. Furthermore, in Japan, where earthquakes are frequent, high earthquake resistance is required for sewer pipes installed underground.

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a method for laying new pipes that can shorten the construction period and improve the corrosion resistance and earthquake resistance of the new pipes. [Means for solving the problem]

[0008] In order to achieve the above object, the method for laying a new pipe as set forth in claim 1 comprises: an excavation trench forming step of forming an excavation trench in the ground; a temporary pipe installation step of installing a temporary pipe, which is a tubular body that is lighter and easier to handle than concrete, in the excavation trench; a main pipe member introducing step of introducing a tubular main pipe member made of an uncured photocurable or thermosetting resin or a flattened thermoplastic resin into the inside of the temporary pipe before or after the temporary pipe installing step; a main pipe member diameter expanding step of supplying a compressed fluid or steam into the inside of the main pipe member to expand the diameter of the main pipe member and bring the main pipe member into close contact with the inner circumferential surface of the temporary pipe; a main pipe member hardening step of hardening the main pipe member by light irradiation, heating, or cooling; Including, The temporary pipe has a strength sufficient to restrict the expansion of the diameter of the main pipe member in the main pipe member expanding step.

[0009] According to this configuration, when a new pipe is to be installed at a location where it is to be installed, for example, between multiple manholes, a trench is formed along the route, and a temporary pipe is placed inside the trench, connecting the manholes. A compressed fluid or steam is then supplied to the inside of a main pipe member, made of uncured resin or flattened thermoplastic resin, introduced into the temporary pipe, thereby expanding the diameter of the main pipe member and bringing it into close contact with the inner periphery of the temporary pipe. Since the temporary pipe has sufficient strength to restrict the expansion of the main pipe member, the expansion of the main pipe member is restricted by the temporary pipe. In this state, the main pipe member is hardened by light irradiation, heating, or cooling, allowing the new pipe to be laid. The excavated trench is then backfilled at a predetermined time after the temporary pipe installation process.

[0010] Furthermore, because this new pipe is made of resin, selecting and adjusting the resin material can improve corrosion resistance in acidic environments. Furthermore, new pipes made of resin materials can have a smoother surface than concrete pipes, allowing for smooth flow of internal fluids. Furthermore, new pipes made of resin are more flexible than concrete pipes, which can improve vibration resistance.

[0011] Furthermore, temporary pipes are tubular bodies that are lighter and easier to handle than concrete and can be easily installed in excavated trenches. This makes it possible to form new pipes from a single, seamless, and highly watertight main pipe, rather than having to connect short pieces like concrete pipes. This eliminates the need to join heavy concrete pipes in narrow excavated trenches and inspect the state of the joints, thereby shortening the construction period.

[0012] The invention described in claim 2 is the method for laying a new pipe described in claim 1, The temporary pipe is made of paper, cloth or resin.

[0013] This configuration allows the temporary pipe to be appropriately lightweight. In other words, the temporary pipe does not ultimately need to function as a new pipe itself; it only needs to function to restrict the expansion of the main pipe during the installation process of the new pipe, ensuring that the main pipe becomes a circular pipe of a predetermined size. Therefore, various lightweight materials can be used. Furthermore, by using a tubular body made of a non-elastic or nearly non-elastic material, the expansion of the main pipe can be easily restricted. This makes it possible to use uncured hardening tubular members, which have traditionally been used to rehabilitate existing pipes from the inside, when installing new pipes.

[0014] The invention described in claim 3 is the method for laying a new pipe described in claim 1 or 2, The trachea is characterized in that it is made of a biodegradable material.

[0015] According to this configuration, the temporary pipe can be naturally decomposed in the ground after installation. The temporary pipe does not necessarily have to be removed, and can be left buried as it is, but according to the above configuration, the temporary pipe can be eliminated without much effort.

[0016] The invention described in claim 4 is the method for laying a new pipe described in claim 1 or 2, The temporary tube is characterized by being formed of a flexible material.

[0017] With this configuration, the main pipe member can be covered with a flexible temporary pipe beforehand, and after the main pipe member is introduced inside the non-stretchable or nearly non-stretchable flexible temporary pipe on the ground, the temporary pipe and the main pipe member can be lowered into the excavation trench at the same time to install the temporary pipe. This makes it easy to introduce the main pipe member (main pipe member introduction process) on the ground where there is a large working space, and because the temporary pipe and main pipe member can be lowered into the excavation trench at the same time, work efficiency can be improved.

[0018] The invention described in claim 5 is the method for laying a new pipe described in claim 1 or 2, The temporary pipe is characterized in that it is formed of a material having a predetermined hardness.

[0019] According to this configuration, since the temporary pipe has a certain degree of shape retention, it is possible to easily introduce the unhardened main pipe member after the temporary pipe has been installed (main pipe member introduction process).

[0020] The invention described in claim 6 is the method for laying a new pipe described in claim 1 or 2, In the temporary pipe installation step, the temporary pipe is installed between a plurality of manholes installed underground, and an alignment jig is provided at a connection portion between the manhole and the temporary pipe; The temporary pipe is a standard cylindrical pipe having an inner diameter substantially the same as the inner diameter of a new pipe connection hole provided so as to penetrate the peripheral wall of the manhole, The alignment jig is characterized by having a cylindrical portion whose outer periphery simultaneously contacts the inner surface of the temporary pipe and the inner surface of the new pipe connection hole when the temporary pipe is joined to the new pipe connection hole of the manhole, and a flange portion that protrudes from the outer periphery of the cylindrical portion and has one surface abutting the outer periphery of the manhole.

[0021] According to this configuration, the alignment jig can align the temporary pipe with the manhole and prevent misalignment. Specifically, first, one end of the tubular portion of the alignment jig is inserted into the new pipe connection hole of the manhole, and one surface of the flange portion of the alignment jig is brought into contact with the outer peripheral surface of the manhole. In this state, the temporary pipe is fitted into the other end of the tubular portion of the alignment jig, and the end surface of the temporary pipe is brought into contact with the other surface of the flange portion of the alignment jig. By connecting the manhole and the temporary pipe via the alignment jig in this way, the center of the new pipe connection hole of the manhole and the temporary pipe can be easily aligned. This allows the center axis of the new pipe (i.e., the hardened main pipe) to be installed inside the temporary pipe to be aligned with the center of the new pipe connection hole of the manhole.

[0022] The invention described in claim 7 is a method for laying a new pipe described in claim 1 or 2, a drilling step of drilling a hole in a peripheral wall of the main pipe member exposed by removing a portion of the temporary pipe after the main pipe member hardening step; an attachment pipe connecting step of connecting an attachment pipe to the drilled portion of the main pipe member via a coupling member, The coupling member is characterized by having a plate-like shape with an arc-shaped cross section that conforms to the outer surface of the main pipe member, a new pipe connection portion having a through hole in the center, and a cylindrical attachment pipe connection portion that protrudes from the outer surface of the new pipe connection portion and surrounds the through hole.

[0023] With this configuration, by joining the new pipe joint portion of the coupling member to the outer circumferential surface of the hardened main pipe member and then joining the attachment pipe to the attachment pipe joint portion of the coupling member, the attachment pipe can be connected to the main pipe member (i.e., the new pipe), and because the connection portion is sealed by the coupling member, the connection portion can be kept waterproof. This reliably prevents groundwater and other contaminants from seeping into the new pipe from the connection portion between the new pipe and the attachment pipe. [Effects of the Invention]

[0024] According to the method for laying new pipes of the present invention, a temporary pipe is placed in an excavation trench, and an unhardened main pipe member is introduced inside the temporary pipe and hardened while the temporary pipe restricts its diameter expansion. This makes it possible to easily lay new resin pipes. This improves the corrosion resistance and earthquake resistance of the new pipes, and also makes it possible to lay long spans of new pipes using a series of main pipe members, thereby shortening the construction period. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a cross-sectional view showing a pipe structure laid by a new pipe laying method according to one embodiment of the present invention. [Figure 2] 1 is a cross-sectional view illustrating a laying system 30 for carrying out a method for laying a new pipe according to one embodiment of the present invention. [Figure 3] FIG. [Figure 4] FIG. 10 is an enlarged cross-sectional view showing the installation state of the alignment jig. [Figure 5A] FIG. 10 is a cross-sectional view showing a modified example of the alignment jig. [Figure 5B] FIG. 10 is a cross-sectional view showing a modified example of the alignment jig. [Figure 6] FIG. [Figure 7] FIG. 10 is a cross-sectional view illustrating the state in which a temporary pipe is installed in an excavation trench. [Figure 8] FIG. 7 is a plan view of FIG. [Figure 9A] FIG. 8 is a cross-sectional view taken along line AA in FIG. 7. [Figure 9B] FIG. 8 is a cross-sectional view taken along line BB in FIG. [Figure 10] 10 is a cross-sectional view illustrating another embodiment of a method for laying a new pipe. FIG. [Figure 11] FIG. 10 is a perspective view showing another embodiment of the temporary pipe. DETAILED DESCRIPTION OF THE INVENTION

[0026] FIG. 1 is a cross-sectional view showing a pipe structure 10 laid by a method for laying a new sewer pipe according to one embodiment of the present invention, and FIG. 2 is a cross-sectional view illustrating an installation system 30 for implementing the method for laying a new sewer pipe according to one embodiment of the present invention. In the following description, the new sewer pipe will also be referred to simply as the "new pipe." Note that the drawings used in the description of the present invention are schematic diagrams and do not precisely depict the dimensions of each component. The new pipe installation method of this embodiment involves laying a new buried pipe between two manholes 11-1 and 11-2 buried underground using an open-cut method. This embodiment describes a method for laying a sewer pipe 20, an example of a new pipe, using a main pipe member 18 made of resin. The sewer pipe 20 is disposed between two adjacent manholes 11-1 and 11-2 to connect them.

[0027] As shown in FIG. 1, the pipe structure 10 includes two manholes 11-1 and 11-2, a temporary pipe 12, an alignment jig 16, a sewer pipe 20 formed by a hardened main pipe member 18, an attachment pipe 22, a joint member 24, and a catch basin 28. As shown in FIG. 2, the laying system 30 includes each of the components constituting the pipe structure 10, as well as a light irradiation device 40 that irradiates light onto the main pipe member 18, a traction device 49, a compressor 32 that serves as a compressed fluid supply means, a styrene concentration detector and a carbon monoxide concentration detector (not shown), a deodorization device 36, and a control device 38. The compressor 32 and the control device 38 are mounted on a construction vehicle 50 located on the ground. Each component of the laying system 30 will be described below.

[0028] First, the main pipe member 18 constituting the sewer pipe 20 will be described. The main pipe member 18 is flexible in an uncured state and is formed into a tubular shape with an inner diameter set to match the inner diameter of the newly installed sewer pipe 20 after curing. Examples of materials that can be used for the main pipe member 18 include a fiber-impregnated base material (e.g., a fiber base material such as glass fiber or polyester fiber) impregnated with a photocurable or thermosetting resin composition (so-called fiber-reinforced resin), and a thermoplastic resin pipe. In this embodiment, the impregnated base material is impregnated with a photocurable resin composition. The photocurable resin composition can include a polymerizable resin, a polymerizable unsaturated monomer, and a photopolymerization initiator. For example, a polymerizable resin such as an unsaturated polyester resin or a vinyl ester resin dissolved in a solvent such as styrene can be used. Examples of photopolymerization initiators that can be used include ultraviolet polymerization initiators that promote resin polymerization under ultraviolet light and photopolymerization initiators that promote resin polymerization under the action of both ultraviolet light and visible light. When laying the sewer pipe 20, the main pipe member 18 is introduced into the temporary pipe 12 in a folded state so that the cross section is approximately ω-shaped.

[0029] The main pipe member 18 includes an inner film and an outer film that protect the inner and outer surfaces, respectively. Examples of materials that can be used for the inner and outer films include polyethylene film, polypropylene film, and polyethylene terephthalate film. The inner film is transparent to at least the light irradiated from the light irradiator 40, and the outer film is preferably a light-shielding film so that the light irradiated from the light irradiator 40 does not penetrate to the outside of the photocurable main pipe member 18 and is used for the photocuring reaction. Examples of light-shielding films that can be used include a laminated film having a colored coating layer, such as yellow, between two transparent polyethylene films. The inner film is peeled off after the main pipe member 18 has cured.

[0030] The temporary pipe 12 restricts the expansion of the main pipe member 18 when the main pipe member 18 hardens, and is installed to connect two manholes 11-1, 11-2 when a new sewer pipe 20 is installed. The temporary pipe 12 of this embodiment is a standard cylindrical pipe set to have the same inner diameter as the inner diameter of the new pipe connection hole 11a provided to penetrate the peripheral wall of the manholes 11-1, 11-2, and one temporary pipe 12 is formed by connecting multiple pipes 13 with pipe connection members 14.

[0031] The temporary pipe 12 is formed of a tubular body that is lighter and easier to handle than concrete, and has the strength to restrict the expansion of the main pipe member 18 in the main pipe member expansion process described below. Examples of such temporary pipes 12 include tubular bodies made of paper, cloth, or resin, and tubular bodies made of lightweight, thin metals such as stainless steel. The temporary pipe 12 is preferably formed of a biodegradable material (e.g., paper or biodegradable resin). The temporary pipe 12 is preferably formed of a material having a predetermined strength. Furthermore, from the viewpoint of workability, the temporary pipe 12 is preferably made of a material that is lighter than the main pipe member 18, and more preferably is a tubular body thinner than the main pipe member 18. For example, the thickness of the main pipe member 18 can be 3 mm to 15 mm, and the thickness of the temporary pipe 12 can be 3 mm or less. In this embodiment, a paper void pipe having a predetermined strength and thinner than the main pipe member 18 is used.

[0032] In this embodiment, a single temporary pipe 12 is formed by connecting multiple pipes 13, which are void pipes, using a pipe connection member 14. The pipe connection member 14 is an annular member attached to the outer circumferential surface of two adjacent pipes 13 so as to straddle the ends of the pipes 13. In this embodiment, a paper pipe connection member 14 is used, and the outer circumferential surfaces of the two adjacent pipes 13 are joined to the inner circumferential surface of the pipe connection member 14 with an adhesive. Both ends of the temporary pipe 12 are installed in a state where they are aligned with respect to the manholes 11-1 and 11-2 using an alignment jig 16.

[0033] FIG. 3 is a perspective view of the alignment jig 16, and FIG. 4 is an enlarged cross-sectional view showing the alignment jig 16 in an installed state. The alignment jig 16 includes a cylindrical portion 16a whose outer periphery contacts both the inner periphery of the temporary pipe 12 and the inner periphery of the new pipe connection hole 11a when the temporary pipe 12 is joined to the new pipe connection hole 11a of the manholes 11-1 and 11-2, and a flange portion 16b protruding from the outer periphery of the cylindrical portion 16a. The cylindrical portion 16a is formed in a thin cylindrical shape whose outer diameter is set to be the same as the inner diameter of the new pipe connection hole 11a. The flange portion 16b is an annular plate protruding from the outer periphery of the axial center of the cylindrical portion 16a. In an installed state, one surface abuts the outer periphery of the manholes 11-1 and 11-2, and the other surface abuts the end face of the temporary pipe 12. The thickness of the tubular portion 16a and the flange portion 16b is preferably 2 mm or less, and more preferably 1 mm or less. The alignment jig 16 can be made of metal or resin, and in this embodiment, the tubular portion 16a and the flange portion 16b are formed from a thin stainless steel plate. Note that the alignment jig 16 may be set so that the end face of the tubular portion 16a on the manhole 11 side is approximately flush with the inner surface of the manhole 11 when installed.

[0034] 5A and 5B are diagrams illustrating modified examples of the alignment jig 16. As shown in FIG. 5A, the tubular portion 16a of the alignment jig 16 has a water stop ring insertion portion 16c formed on the peripheral wall that is closer to the temporary pipe 12 than the flange portion 16b when the jig is installed. The water stop ring insertion portion 16c is an annular groove formed by the peripheral wall of the tubular portion 16a projecting radially outward to form a large inner diameter. A water stop ring 17 formed in an annular shape is inserted into the water stop ring insertion portion 16c. The water stop ring 17 may be, for example, a rubber O-ring, and is preferably water-swellable. Because the temporary pipe 12 is formed from a material such as paper or cloth, it can be easily reshaped to match the shape of the water stop ring insertion portion 16c.

[0035] In another modification of the positioning jig 16 shown in Fig. 5B, a portion of the waterstop ring insertion portion 16c is formed by a part of the flange portion 17. In this manner, the flange portion 17 and the waterstop ring insertion portion 16c may be formed adjacent to each other. In the positioning jig 16 shown in Fig. 5B, the waterstop ring insertion portion 16c is formed with a rectangular cross section, and in the installed state, the edge of the temporary pipe 12 abuts against the outer wall surface of the waterstop ring insertion portion 16c.

[0036] Next, the light irradiation device 40, compressor 32, styrene concentration detector, carbon monoxide concentration detector, deodorizing device 36, and control device 38 used when curing the main pipe member 18 will be described with reference to FIG.

[0037] The light irradiation device 40 includes a light irradiation unit 41, a support unit 42, a temperature sensor 43, an imaging unit 44, and traveling means 46, such as wheels, for moving the light irradiation device 40. The light irradiation device 40 is connected to a traction device 49 via a cable 48. During the light curing operation of the main pipe member 18, which will be described later, the light irradiation device 40 can be advanced from one end (the side of one manhole 11-2) to the other end (the side of the other manhole 11-1) within the main pipe member 18 by pulling the cable 48. The light irradiation device 40 is also connected via the cable 48 to a control device 38 mounted on a construction vehicle 50 on the ground. In the following description, the forward side of the light irradiation device 40 in the traveling direction (the left side in FIG. 2) is referred to as the forward side, and the rearward side of the traveling direction (the right side in FIG. 2) is referred to as the rearward side.

[0038] A plurality of light irradiation units 41 are provided in a row in the direction of travel of the light irradiation device 40. Each light irradiation unit 41 is configured with a plurality of LEDs (light-emitting diodes) on the outer surface of a cylindrical main body. As shown in FIG. 2, both ends of each light irradiation unit 41 are supported by a support 42, and a conductor for supplying power to each LED of the light irradiation unit 41 is inserted between the main body of the light irradiation unit 41 and the support 42. This conductor passes through a cable 48 and is connected to a power supply unit mounted on a ground construction vehicle 50. The on / off and irradiation output of each light irradiation unit 41 can be individually controlled by the control device 38. Traveling means 46 are provided between each light irradiation unit 41 to enable movement within the pipeline while preventing the light irradiation unit 41 from colliding with the inner wall of the main pipe member 18 during the light curing operation.

[0039] The temperature sensor 43 measures the inner surface temperature of the main pipe member 18 and the atmospheric temperature inside the main pipe member 18, and is attached to the support body 42. Note that a plurality of temperature sensors 32 may be provided. The measurement data of the temperature sensor 43 is transmitted to the control device 38 via a conductor in the cable material 48. The imaging means 44 is, for example, a television camera capable of capturing images inside the pipe, and is installed at the rear end and / or front end of the light irradiation device 40. The captured image data is transmitted to the control device 38 and displayed on a display means (for example, a monitor screen) of the control device 38.

[0040] The compressor 32 supplies compressed air to the inside of the main pipe member 18 via a hose 33A. The amount of compressed air supplied by the compressor 32 can be adjusted automatically or manually by a control device 38. The laying system 30 may be configured to include a cooler that cools the air together with the compressor 32, so that cooled compressed air can be supplied.

[0041] The styrene concentration detector and carbon monoxide concentration detector are disposed downstream of main pipe member 18 in the direction of compressed air supply and upstream of deodorizing device 16, and measure the styrene concentration and carbon monoxide concentration, respectively, in the air that has passed through main pipe member 18. Deodorizing device 36 is disposed on the ground, and the gas discharged from main pipe member 18 is taken into deodorizing device 36, which is also disposed on the ground, via hose 33B, thereby performing odor treatment to remove odor-causing substances contained in the gas that has passed through main pipe member 18.

[0042] The control device 38 is configured to include, for example, a microcomputer having operation means such as an operation panel and switch buttons, and display means such as a monitor screen, as well as information processing means such as a CPU, storage means such as RAM and ROM, an input / output interface, etc. The control device 38 is connected to each of the light irradiation device 40, compressor 32, styrene concentration detector, carbon monoxide concentration detector, and deodorization device 36 by wire or wirelessly, and is capable of recording data received from these devices. Furthermore, the control device 38 can control the operating states of the light irradiation device 40, compressor 32, and deodorization device 36 based on the received data. For example, the control device 38 is configured to be able to control the traveling speed of the light irradiation device 40, the irradiation output of the light irradiation unit 41, the amount of compressed air supplied by the compressor 32, etc., based on the measurement results of the temperature sensor 43.

[0043] Next, we will explain the attachment pipe 22 attached to the sewer pipe 20. As shown in Figure 1, the attachment pipe 22 connects the sewer pipe 20 to a catchment basin 28 installed on the ground side, and is a pipe that sends sewage in the catchment basin 28 into the sewer pipe 20, and one end of the attachment pipe 22 is connected to the circumferential surface of the sewer pipe 20. The attachment pipe 22 is connected to the hardened main pipe member 18 that constitutes the sewer pipe 20 via a coupling member 24.

[0044] As shown in Figures 1 and 6, the coupling member 24 has a new pipe coupling portion 24a and an attachment pipe coupling portion 24b. The new pipe coupling portion 24a is formed in the shape of a plate with an arc-shaped cross section that conforms to the outer circumferential surface of the hardened main pipe member 18 and has a through-hole in the center. The attachment pipe coupling portion 24b protrudes from the convex outer surface of the new pipe coupling portion and is formed in a cylindrical shape that surrounds the through-hole of the new pipe coupling portion 24a. The inner surface of the new pipe coupling portion 24a is joined to the outer circumferential surface of the main pipe member 18, and the outer circumferential surface of the attachment pipe coupling portion 24b is joined to the inner circumferential surface of the attachment pipe 22 using an adhesive or the like. These joinings can be performed using an adhesive, welding, or the like.

[0045] Next, a method for laying a sewer pipe 70 using the above-described laying system 30 will be described. The laying method includes an excavation trench formation step of forming an excavation trench 70 in the ground, a temporary pipe installation step of installing a temporary pipe 12 in the excavation trench 70, a main pipe member introduction step of introducing an unhardened main pipe member 18 into the temporary pipe 12, a main pipe member expansion step of expanding the diameter of the main pipe member 18 to fit closely against the inner circumferential surface of the temporary pipe 12, a main pipe member hardening step of hardening the main pipe member 18, a hole drilling step of drilling a hole in the peripheral wall of the main pipe member 18, a lateral pipe connection step of connecting an lateral pipe 22 to the drilled portion, and a backfilling step. Each step will be described in detail below.

[0046] First, as shown in Figures 7 and 8, the ground is excavated to form an excavation trench 70 in the path between the manholes 11-1 and 11-2 installed underground (excavation trench forming step). After that, a temporary pipe 12 connecting the manholes 11-1 and 11-2 is installed inside the excavation trench 70 (temporary pipe installation step). The excavation trench 70 is formed using an excavator (not shown), and is formed in a substantially trapezoidal shape with a width dimension W2 of the trench bottom that is smaller than a width dimension W1 of the upper opening, as shown in Figure 9A.

[0047] The temporary pipe 12 is installed between multiple manholes installed underground. The installed temporary pipe 12 is constructed as a tubular body that is lighter and easier to handle than concrete, making it easy to lower into the excavation trench 70 and install within the excavation trench 70. An alignment jig 16 is disposed at the connection between the temporary pipe 12 and the manhole 11, and the temporary pipe 12 is connected to the new pipe connection holes 11a of the manholes 11-1 and 11-2 via the alignment jig 16. Specifically, one end of the tubular portion 16a of the alignment jig 16 is inserted into the new pipe connection hole 11a, and one surface of the flange portion 16b is brought into contact with the outer peripheral surfaces of the manholes 11-1 and 11-2. In this state, one end of the temporary pipe 12 is fitted into the other end of the tubular portion of the alignment jig 16, and the end face of the temporary pipe 12 is brought into contact with the other surface of the flange portion 16b. By joining them in this manner, the temporary pipe 12 is aligned with the manholes 11-1 and 11-2 so that the inner peripheral surface of the new pipe connection hole 11a of the manholes 11-1 and 11-2 and the inner peripheral surface of the temporary pipe 12 are flush with each other.

[0048] After the temporary pipe installation process, an unhardened main pipe member 18 is introduced into the installed temporary pipe 12 (main pipe member introduction process). The main pipe member 18 is introduced into the temporary pipe 12 in a folded state so that its cross section has an ω-shaped shape. The folded main pipe member 18 can be introduced into the temporary pipe 12, for example, by installing a towing device (not shown) on the ground and attaching a towing rope from this towing device to the tip of the main pipe member 18 and towing it. Specifically, the main pipe member 18 is introduced into the temporary pipe 12 from one manhole 11-1, and the main pipe member 18 can be pulled into the temporary pipe 12 by pulling the towing rope attached to the main pipe member 18 from the other manhole 11-2 side.

[0049] After the main pipe member 18 has been introduced, as shown in Figure 2, the compressor 32 is driven to supply compressed fluid into the inside of the main pipe member 18 via the hose 33A, thereby expanding the diameter of the main pipe member 18 and bringing the main pipe member 18 into close contact with the inner circumferential surface of the temporary pipe 12 (main pipe member diameter expansion process). In this process, the openings at both ends of the main pipe member 18 are closed by the closing members 34. The temporary pipe 12 has enough strength to restrict the movement of the main pipe member 18 in expanding its diameter, so the expansion of the main pipe member 18 is restricted by the temporary pipe 12. The light irradiation device 40 is introduced into the main pipe member 18 after expanding the main pipe member 18 to a required size with compressed air.

[0050] Next, the main pipe member 18 is cured by irradiating it with light from inside the main pipe member 18 using the light irradiation device 40 (main pipe member curing process). In this process, compressed air is supplied to the inside of the main pipe member 18 while light irradiation is performed, and gas heated by the heat generated by the curing reaction is sent from one end of the main pipe member 18 to the other end, as indicated by the white arrow. The air is sent in the opposite direction to the direction of travel of the light irradiation device 40 (the direction indicated by the black arrow in Figure 2). During movement, the image capture means 44 captures images of the inner surface of the main pipe member 18 to check for curing defects, etc. Furthermore, the temperature sensor 43 and various detectors are used to confirm that the measured temperature, measured concentration, etc. are within the specified control value ranges while the process is performed.

[0051] When the main pipe member 18 is made of a thermosetting fiber-reinforced resin, the main pipe member 18 is hardened by heating the main pipe member 18 from the inside. Heating can be performed, for example, by supplying a high-temperature fluid (e.g., air or hot water) into the inside of the main pipe member 18.

[0052] After the curing operation is completed, the light irradiation device 40 is removed, the inner film is peeled off, and the pipe opening process is performed on the cured main pipe member 18. In the pipe opening process, the main pipe member 18 is cut at the joint between the cured main pipe member 18 and the manholes 11-1 and 11-2 to match the opening shapes of the manholes 11-1 and 11-2.

[0053] After the main pipe member hardening step, a portion of the temporary pipe 12 is removed to expose the peripheral wall of the main pipe member 18, and a hole is drilled in the peripheral wall (hole drilling step). The attachment pipe 22 is then connected to the drilled portion of the main pipe member 18 via the coupling member 24 (attachment pipe connecting step). In this embodiment, after the new pipe coupling portion 24a of the coupling member 24 is coupled to the outer peripheral surface of the exposed main pipe member 18, a hole is drilled in the peripheral wall of the main pipe member 18 to match the inner diameter of the attachment pipe coupling portion 24b of the coupling member 24. One end of the attachment pipe 22 is then coupled to the attachment pipe coupling portion 24b. This allows the attachment pipe 22 to be formed, branching off from the main pipe member 18.

[0054] After the attachment pipe 22 is connected to the main pipe member 18, the excavation trench 70 is backfilled (backfilling process). Note that the backfilling process does not have to be performed after the attachment pipe 22 is connected, but can be performed at a predetermined time after the temporary pipe installation process. The excavation trench 70 can be backfilled using the original ground, for example.

[0055] As described above, in the laying method of this embodiment, the unhardened main pipe member 18 introduced into the temporary pipe 12 is adhered to the inner surface of the temporary pipe 12 by compressed fluid, and the main pipe member 18 is then hardened in this state, thereby laying the sewer pipe 20. Because the newly installed sewer pipe 20 is made of fiber-reinforced resin, it can have improved corrosion resistance in environments where acidic liquids flow. Furthermore, the fiber-reinforced resin sewer pipe 20 can have a smoother surface than a concrete pipe, allowing sewage to flow smoothly downstream. Furthermore, because the sewer pipe 20 is made of a resin material that is more flexible than concrete, it can also have improved vibration resistance. Furthermore, the temporary pipe 12 used to harden the main pipe member 18 is a tubular body that is lighter and easier to handle than concrete, allowing it to be easily installed even in a narrow excavation trench 70. Furthermore, the newly installed sewer pipe 20 can be formed from a continuous, seamless main pipe member 18, even over long installation distances. In this way, the laying method of this embodiment can improve the corrosion resistance of the newly installed pipe, and can eliminate the work of joining heavy concrete pipes in a narrow excavation trench and inspecting the joining condition, allowing a long-span sewer pipe 20 to be laid using a series of main pipe components 18, thereby shortening the construction period.

[0056] The temporary pipe 12 used in the installation method of this embodiment can be appropriately lightweight. That is, the temporary pipe 12 does not ultimately need to function as a new pipe itself; it is sufficient if it functions to support the main pipe member 18 during the installation process and to restrict the expansion of the main pipe member 18. Therefore, various lightweight materials can be used for the temporary pipe 12. Furthermore, by using a tubular body made of a non-elastic or nearly non-elastic material for the temporary pipe 12, the expansion of the main pipe member 18 can be easily restricted. This allows the use of tubular members made of uncured curable fiber-reinforced resin, which have previously been used to rehabilitate existing pipes from the inside, when installing a new pipe. Furthermore, in this embodiment, the temporary pipe 12 is a void pipe and has a certain degree of shape retention, so that after the temporary pipe 12 is installed, the uncured main pipe member 18 can be easily introduced later.

[0057] After the sewer pipe 20 is installed, the temporary pipe 12 does not necessarily need to be removed, and can be left buried as is. In this embodiment, a lightweight paper tubular body is used as the temporary pipe 12, which makes it easy to install the temporary pipe 12, and after the excavation trench 70 is backfilled, the temporary pipe 12 can be naturally decomposed in the ground. This allows the temporary pipe 12 to disappear without the effort of removing it.

[0058] Furthermore, in the laying method of this embodiment, the alignment jig 16 can easily align the center of the new pipe connection hole 11a of the manholes 11-1 and 11-2 with the central axis of the temporary pipe 12, thereby aligning the center of the temporary pipe 12 with the manhole 11 and preventing misalignment. This allows alignment so that the central axis of the sewer pipe 20 installed inside the temporary pipe 12 coincides with the center of the new pipe connection hole 11a of the manholes 11-1 and 11-2.

[0059] When the alignment jig 16 has a watertight ring 17 as shown in Figures 5A and 5B, even if the sewer pipe 20 is displaced axially after being laid, for example due to an earthquake, the watertightness of the connection between the manhole 11 and the sewer pipe 20 can be maintained, and it is possible to prevent groundwater from seeping into the sewer pipe 20 or manhole 11 through this connection.

[0060] Furthermore, the sewer pipe 20 and the attachment pipe 22 are connected via an integrated joint member 24 having a new pipe joint portion 24a and an attachment pipe joint portion 24b, and the connection portion is sealed by the joint member 24, thereby maintaining the waterproofing of the connection portion. This reliably prevents groundwater and the like from seeping into the sewer pipe 20 from the connection portion between the sewer pipe 20 and the attachment pipe 22.

[0061] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the invention.

[0062] For example, if the section between two adjacent manholes 11 is considered to be one section, it is possible to simultaneously install two or more sections of sewer pipe 20 using one main pipe member 18, as shown in Figure 10. A temporary pipe 12 is also installed inside a manhole 11 located within the section, and the main pipe member 18 is introduced into the temporary pipe 12 so as to pass through the manhole 11 located within the section. The temporary pipe 12 and main pipe member 18 inside the manhole 11 are removed during pipe mouth processing after the main pipe member 18 has hardened. This allows for efficient installation of sewer pipe 20 over multiple sections, and shortens the construction period.

[0063] Furthermore, in each embodiment, the temporary pipe 12 may be a deformable tubular body made of a flexible material, as shown in FIG. 11 , rather than a rigid, standard tubular body, as long as it has the strength to restrict the radial expansion of the main pipe member 18. The deformable temporary pipe 12 may be, for example, a tubular body formed by rolling a fabric or sheet material into a cylindrical shape. When using a deformable temporary pipe 12, the temporary pipe 12 may be lowered into the excavation trench 70 with the main pipe member 18 folded into an ω shape and pre-inserted inside the temporary pipe 12, as shown in FIG. 11 , and both ends of the temporary pipe 12 may be joined to the periphery of the new pipe connection hole 11a of the manhole 11. In this way, the main pipe member introduction process may be performed before the temporary pipe installation process. In such a case, the main pipe member introduction process can be easily performed on the ground with a large working space. Furthermore, the temporary pipe 12 and the main pipe member 18 can be lowered into the excavation trench 70 at the same time. This reduces the amount of work required in the excavation trench 70 and improves work efficiency.

[0064] Alternatively, the main pipe member 18 may be made of a thermoplastic resin pipe such as polyvinyl chloride or polyethylene. For example, the main pipe member 18, which is a flattened thermoplastic resin pipe, is introduced into the temporary pipe 12 (main pipe member introduction process), and the main pipe member 18 is then heated to expand the diameter of the main pipe member 18 and bring the outer circumferential surface of the main pipe member 18 into close contact with the inner wall surface of the temporary pipe 12 (main pipe member diameter expansion process). In this state, the main pipe member 18 is cooled to harden the main pipe member 18 (main pipe member hardening process). The cylindrical thermoplastic resin pipe is flattened in a factory and transported to the site wound around a winding drum. The flattened thermoplastic resin pipe has an ω-shaped cross section. After being introduced into the temporary pipe 12, it can be heated from the inside by heated compressed air or steam, thereby recovering its cylindrical shape and expanding its diameter. The new pipes laid by the laying method according to the present invention are not limited to new sewage pipes, but may also be new pipes for industrial water or agricultural water, for example. [Explanation of symbols]

[0065] 10 Pipe structure 11-1, 11-2 Manhole 11a New pipe connection hole 12 Temporary tube 16 Alignment jig 16a Cylindrical part 16b Flange part 16c Water stop ring insertion part 17 Water stop ring 18 Main pipe member 20 Sewer pipe (new pipe) 22 Mounting pipe 24 Joint member 24a New pipe joint 24b Mounting pipe joint 32 Compressor 38 Control Device 40 Light irradiation device

Claims

1. an excavation trench forming step of forming an excavation trench in the ground; a temporary pipe installation step of installing a temporary pipe, which is a tubular body that is lighter and easier to handle than concrete, in the excavation trench; a main pipe member introducing step of introducing a tubular main pipe member made of an uncured photocurable or thermosetting resin or a flattened thermoplastic resin into the inside of the temporary pipe before or after the temporary pipe installing step; a main pipe member diameter expanding step of supplying a compressed fluid or steam into the inside of the main pipe member to expand the diameter of the main pipe member and bring the main pipe member into close contact with the inner circumferential surface of the temporary pipe; a main pipe member hardening step of hardening the main pipe member by light irradiation, heating, or cooling; Including, A method for laying a new pipe, characterized in that the temporary pipe has a strength that is capable of restricting the expansion of the main pipe member during the main pipe member expansion step.

2. 2. The method for laying a new pipe according to claim 1, wherein the temporary pipe is made of paper, cloth or resin.

3. 3. The method for laying a new pipe according to claim 1, wherein the temporary pipe is made of a biodegradable material.

4. 3. The method for laying a new pipe according to claim 1, wherein the temporary pipe is made of a flexible material.

5. 3. The method for laying a new pipe according to claim 1, wherein the temporary pipe is made of a material having a predetermined hardness.

6. In the temporary pipe installation step, the temporary pipe is installed between a plurality of manholes installed underground, and an alignment jig is provided at a connection portion between the manhole and the temporary pipe; The temporary pipe is a standard cylindrical pipe having an inner diameter substantially the same as the inner diameter of a new pipe connection hole provided so as to penetrate the peripheral wall of the manhole, A method for laying a new pipe as described in claim 1 or 2, characterized in that the alignment jig has a cylindrical portion whose outer periphery simultaneously contacts the inner surface of the temporary pipe and the inner surface of the new pipe connection hole when the temporary pipe is joined to the new pipe connection hole of the manhole, and a flange portion that protrudes from the outer periphery of the cylindrical portion and has one surface abutting the outer periphery of the manhole.

7. a drilling step of drilling a hole in a peripheral wall of the main pipe member exposed by removing a portion of the temporary pipe after the main pipe member hardening step; an attachment pipe connecting step of connecting an attachment pipe to the drilled portion of the main pipe member via a coupling member, A method for laying a new pipe as described in claim 1 or 2, characterized in that the coupling member is a plate-shaped member with an arc-shaped cross section that conforms to the outer surface of the main pipe member, and has a new pipe connection portion with a through hole in the center, and a cylindrical attachment pipe connection portion that protrudes from the outer surface of the new pipe connection portion and surrounds the through hole.

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