Method of laying rehabilitation pipes and rehabilitation pipes

Abstract

To provide a method for laying a rehabilitated pipe and a rehabilitated pipe that can prevent poor hardening of the lining material. [Solution] The method for laying a rehabilitated pipe comprises a first step of placing a tubular structure having a lining material that is tubular and contains a curable resin, and a sensor that is in contact with the outer surface of the lining material, inside an existing pipe, and a second step of curing the lining material after the first step, wherein the sensor has a pair of electrodes that are in contact with the outer surface and measure the electrical properties of the lining material, and in the second step, the completion of curing of the lining material is determined and / or the curing conditions of the lining material are adjusted based on the detection result of the sensor.

Description

Technical Field

[0001] The present disclosure relates to a method for laying a rehabilitation pipe and a rehabilitation pipe.

Background Art

[0002] In recent years, as a method for repairing pipelines (existing pipes) such as existing sewer pipelines, a rehabilitation method using a lining material has been implemented. In this rehabilitation method, after arranging a lining material containing a curable resin inside the pipeline, the lining material is cured to line the pipeline from the inner surface. In such a rehabilitation method, a method for determining whether the entire lining material has been sufficiently cured has not been established. In many cases, by curing the lining material in accordance with appropriately preset curing conditions, it is regarded that the entire lining material has been sufficiently cured. However, curing the lining material in accordance with appropriately preset curing conditions does not quantitatively evaluate that the outer peripheral surface of the lining material has been sufficiently cured, and it can be said that there is a risk such as construction defects.

[0003] Patent Document 1 below discloses a pipeline lining method in which a lining material impregnated or coated with an uncured curable resin is arranged inside the pipeline, the lining material is pressed against the inner wall of the pipeline, and the curable resin is cured to line the pipeline from the inner surface. In this pipeline lining method, the capacitance or dielectric constant of the curable resin impregnated or coated on the lining material is measured, and the curing of the curable resin is determined based on the decrease in the capacitance or dielectric constant. The capacitance or dielectric constant of the curable resin is obtained by measuring the capacitance or dielectric constant between a conductive member located on the inner surface of the pipeline and a conductive member located on the ground or underground.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

[0005] The measurement of electrical properties such as capacitance or dielectric constant between two conductive members disclosed in Patent Document 1 is prone to large measurement errors due to factors such as the distance between the two conductive members. Therefore, the accuracy of determining the completion of curing of the curable resin disclosed in Patent Document 1 is not necessarily high. In other words, even when using the method disclosed in Patent Document 1, there is a concern that curing defects may occur in a part of the lining material.

[0006] One aspect of this disclosure is to provide a method for laying a rehabilitated pipe and a rehabilitated pipe that can prevent hardening defects of the lining material. [Means for solving the problem]

[0007] A method for laying a rehabilitation pipe according to one aspect of this disclosure comprises a first step of placing a rehabilitation pipe, which is tubular and includes a lining material containing a curable resin, a tubular outer covering material covering the outer surface of the lining material, and a sensor in contact with the outer surface of the lining material, into an existing pipe; and a second step of curing the lining material after the first step, wherein the sensor has a pair of electrodes that are in contact with the outer surface and measure the dielectric constant of the lining material, and in the second step, the completion of curing of the lining material is determined and / or the curing conditions of the lining material are adjusted based on the detection result of the sensor.

[0008] In this pipe laying method, the dielectric constant of the outer surface of the lining material is directly detected by a sensor in the second step. Based on the detection result of the sensor, it is determined that the lining material has completed hardening, and / or the hardening conditions of the lining material are adjusted. By using the sensor's detection result, it is possible to accurately determine that the lining material has hardened sufficiently to the outer surface. Furthermore, by adjusting the hardening conditions of the lining material based on the sensor's detection result, it becomes easier to ensure that the lining material hardens sufficiently to the outer surface. Therefore, by using the above pipe laying method, it is possible to prevent hardening defects in the lining material.

[0009] In the second step, the lining material may be heat-cured or light-cured. In either case, the above method of laying the rehabilitated pipe can prevent improper curing of the lining material.

[0010] Each of the pair of electrodes may have a comb-like shape. In this case, the change in dielectric constant on the outer surface of the lining material can be detected with high accuracy.

[0011] In the first step, two or more rehabilitation pipes are placed inside the existing pipe, and in the second step, the hardening conditions of the lining material may be adjusted based on the detection results of sensors contained in each of the two or more rehabilitation pipes. In this case, by utilizing the detection results of each sensor, the laying period of the rehabilitation pipes can be optimized while reducing the use of excessive energy during the laying of the rehabilitation pipes.

[0012] The rehabilitation pipe has two or more sensors, which are spaced apart from each other and aligned along the long axis of the rehabilitation pipe. In the second step, the position of the heat source or light source inside the existing pipe may be adjusted based on the detection results of each of the two or more sensors. In this case, by utilizing the detection results of each of the two or more sensors, the installation period of the rehabilitation pipe can be optimized while reducing the use of excessive energy during the installation of the rehabilitation pipe.

[0013] A rehabilitation pipe relating to one aspect of this disclosure comprises a tubular lining material containing a curable resin, and a sensor in contact with the outer surface of the lining material, the sensor having a pair of electrodes in contact with the outer surface and for measuring the electrical properties of the lining material.

[0014] This rehabilitation pipe allows for the measurement of changes in the electrical properties of the outer surface of the lining material using sensors. Therefore, when curing the lining material, the detection results from the sensors can be used to accurately determine when the outer surface of the lining material has sufficiently cured. Thus, by using the above rehabilitation pipe, it is possible to prevent curing defects in the lining material.

[0015] Each of the pair of electrodes may have a comb-like shape. In this case, the change in dielectric constant on the outer surface of the lining material can be detected with high accuracy.

[0016] The rehabilitation tube described above further comprises a tubular outer covering material that covers the outer surface of the lining material, and the pair of electrodes may be attached to the inner surface of the tubular outer covering material. In this case, the positions of each of the pair of electrodes in the rehabilitation tube are less likely to change.

[0017] The sensor may be installed at the outlet end of the tubular outer covering. In this case, it is possible to accurately determine that the entire rehabilitated pipe has hardened sufficiently.

[0018] The rehabilitation pipe described above may be equipped with two or more sensors, which may be spaced apart from each other and aligned along the long axis of the rehabilitation pipe. In this case, by utilizing the detection results of each of the two or more sensors, the installation period of the rehabilitation pipe can be optimized while reducing the use of excessive energy during the installation of the rehabilitation pipe. [Effects of the Invention]

[0019] According to one aspect of this disclosure, a method for laying a rehabilitated pipe and a rehabilitated pipe that can prevent hardening defects of the lining material can be provided. [Brief explanation of the drawing]

[0020] [Figure 1]FIG. 1 is a schematic perspective view showing a state in which a rehabilitation pipe according to an embodiment is arranged inside an existing pipe. [Figure 2] FIG. 2 is a schematic cross-sectional view showing a state in which a rehabilitation pipe according to an embodiment is arranged inside an existing pipe. [Figure 3] FIG. 3 is a schematic view showing an example of a specific shape of a sensor according to an embodiment. [Figure 4] FIG. 4 is a flowchart for explaining a method of laying a rehabilitation pipe. [Figure 5] FIG. 5 is a schematic perspective view showing a state in which a rehabilitation pipe according to a modification is arranged inside an existing pipe. [Figure 6] FIG. 6 is a diagram showing temperature change and ionic viscosity change of a laminate with respect to light irradiation time.

MODE FOR CARRYING OUT THE INVENTION

[0021] Hereinafter, embodiments of a rehabilitation pipe and a method of laying the same according to the present disclosure will be described with reference to the drawings. In the description of the drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant descriptions are omitted as appropriate. The drawings may be drawn with some parts simplified or exaggerated for ease of understanding, and dimensional ratios and the like are not limited to those described in the drawings.

[0022] FIG. 1 is a schematic perspective view showing a state in which a rehabilitation pipe according to the present embodiment is arranged inside an existing pipe. FIG. 2 is a schematic cross-sectional view showing a state in which a rehabilitation pipe according to the present embodiment is arranged inside an existing pipe. The rehabilitation pipe 1 shown in FIGS. 1 and 2 is a tubular member for reinforcing an existing pipe 100 such as an aging water supply and sewer pipe. By using the rehabilitation pipe 1, infrastructure improvement of water supply and sewerage can be carried out without replacing the existing pipe 100. In the present embodiment, the rehabilitation pipe 1 has a tubular cover film 10, a tubular lining material 20, a tubular exterior material 30, and a sensor 40. The rehabilitation pipe 1 is formed from a tubular structure (not shown) having at least the lining material 20 and the sensor 40 before curing (details will be described later).

[0023] The cover film 10 is a tubular member that protects the lining material 20 when laying the rehabilitated pipe 1, and is flexible. When transporting the tubular structure, the cover film 10 defines the inner circumferential surface of the rehabilitated pipe 1. The cover film 10 has, for example, at least one of light transmittance and heat resistance. The cover film 10 is, for example, a tubular molded body of a known resin film. The cover film 10 may be peelable from the lining material 20. In this case, after laying the rehabilitated pipe 1 on the existing pipe 100, the inner circumferential surface of the rehabilitated pipe 1 can be defined by the lining material 20. The resin film that constitutes the cover film 10 is, for example, a urethane elastomer film, a polyamide film, a polyethylene terephthalate film, a polyester elastomer film, etc. The cover film 10 may be a tube with a single-layer structure or a tube with a multi-layer structure. A tube having a multilayer structure may be formed, for example, by laminating each layer or by inserting each layer.

[0024] The lining material 20 is a tubular member that becomes the main part of the rehabilitated pipe 1 after it is laid on the existing pipe 100. During transportation of the tubular structure and during the laying of the rehabilitated pipe 1 on the existing pipe 100, the inner circumferential surface 20a of the lining material 20 is covered by the cover film 10. After the rehabilitated pipe 1 is laid, the inner circumferential surface 20a can function as the inner circumferential surface of the rehabilitated pipe 1. The lining material 20 hardens when the rehabilitated pipe 1 is laid. For this reason, before the laying of the rehabilitated pipe 1, the lining material 20 is flexible. That is, the unhardened lining material 20 included in the tubular structure is flexible. The lining material 20 is thermosetting or photocuring. The thickness of the lining material 20 is, for example, 2 mm or more and 50 mm or less.

[0025] If the lining material 20 is thermosetting, it hardens by supplying, for example, hot water or steam into the rehabilitated pipe 1. If the lining material 20 is photocurable, it hardens by irradiation with light such as ultraviolet rays, electron beams, alpha rays, beta rays, or gamma rays. An example of a hardening device is a heating device (heat source) for the lining material 20, which supplies heated hot water or steam into the rehabilitated pipe 1 from a position away from the rehabilitated pipe 1. Another example of a hardening device is a light irradiation device (light source), which irradiates light toward the lining material 20 within the rehabilitated pipe 1 and may also be movable within the rehabilitated pipe 1. Examples of the light sources include germicidal lamps, ultraviolet fluorescent lamps, carbon arc lamps, xenon lamps, high-pressure mercury lamps for copying, medium-pressure or high-pressure mercury lamps, ultra-high-pressure mercury lamps, electrodeless lamps, metal halide lamps, fluorescent chemical lamps, and LED lamps. Whether the lining material 20 is thermosetting or photocurable, hardening progresses from the inner circumference to the outer circumference of the lining material 20. In other words, the outer surface 20b of the lining material 20 is the least likely to harden. The outer surface 20b only needs to function as the outer surface of the lining material 20 at least after the rehabilitated pipe 1 has been laid. Therefore, the outer surface 20b may function as the inner surface of the lining material 20 during transportation of the tubular structure.

[0026] In this embodiment, the lining material 20 is a resin and a member (prepreg) in which fibers are impregnated with the resin. The resin includes at least one of a photocurable resin and a thermosetting resin. The photocurable resin has the property of curing by irradiation with light such as ultraviolet light, and is a resin composition that includes, for example, a resin component (A) in which epoxy (meth)acrylate (a1) and an unsaturated monomer (a2) are essential components, and a photopolymerization initiator (B). The thermosetting resin is, for example, a resin composition that includes an unsaturated polyester resin, a polymerizable monomer, and a thixotropy-imparting agent as essential components. In this specification, "(meth)acrylate" means one or both of acrylate and methacrylate, and "(meth)acrylic acid" means one or both of acrylic acid and methacrylic acid.

[0027] The epoxy (meth)acrylate (a1) contained in the resin component (A) of the photocurable resin can be obtained, for example, by reacting an epoxy resin with (meth)acrylic acid. The reaction between the epoxy resin and (meth)acrylic acid is carried out, for example, at 60°C to 140°C using an esterification catalyst. Polymerization inhibitors may be used at this time.

[0028] Examples of epoxy resins include novolac epoxy resins, alicyclic epoxy resins, heterocyclic epoxy resins, glycidyl ethers of phenols, glycidyl ethers of polyhydric alcohols, glycidyl esters, and glycidylamines. Examples of novolac epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol fluorene type epoxy resin, biscresol fluorene type bisphenol epoxy resin, phenol novolac type epoxy resin, and cresol novolac type epoxy resin. Examples of alicyclic epoxy resins include 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate and 1-eposiethyl-3,4-epoxycyclohexane. Examples of heterocyclic epoxy resins include 1,3-diglycidyl-5,5-dimethylhydantoin and triglycidyl isocyanurate. Glycidyl ethers of phenols include oxodoridone-modified epoxy resins and brominated epoxy resins of these resins. Glycidyl ethers of polyhydric alcohols include dipropylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, diglycidyl ether of alkylene oxide adducts of bisphenol A, and diglycidyl ether of hydrogenated bisphenol A. Glycidyl esters include diglycidyl esters of phthalates, diglycidyl esters of tetrahydrophthalates, diglycidyl-p-oxybenzoic acid, and dimer acid glycidyl esters. Glycidylamines include tetraglycidyldiaminodiphenylmethane, tetraglycidyl-m-xylenediamine, triglycidyl-p-aminophenol, and N,N-diglycidylaniline. From the viewpoint of refractive index stability and thick film curing properties of resin component (A), the epoxy resin may also be a bisphenol A type epoxy resin. Furthermore, epoxy resins may be used individually or in combination of two or more types.

[0029] The unsaturated monomer (a2) contained in resin component (A) is, for example, monofunctional (meth)acrylate compounds, di(meth)acrylate compounds, diallyl phthalate, and divinylbenzene. Functional (meth)acrylate compounds are, for example, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, polyethylene glycol (meth)acrylate alkyl ether, polypropylene glycol (meth)acrylate alkyl ether, 2-ethylhexyl methacrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, isotridecyl (meth)acrylate, n-stearyl (meth)acrylate, tetrahydrofurfuryl methacrylate, isobornyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, and dicyclopentanyl methacrylate. Di(meth)acrylate compounds include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, bisphenol di(meth)acrylate, and 1,4-cyclohexanedimethanol di(meth)acrylate. From the viewpoint of the refractive index of resin component (A) and thick-film curing properties, the unsaturated monomer (a2) may also be phenoxyethyl (meth)acrylate. These unsaturated monomers (a2) can be used alone or in combination of two or more.

[0030] From the viewpoint of balancing the impregnation and curability of the fibers in the resin, the mass ratio (a1 / a2) of epoxy (meth)acrylate (a1) and unsaturated monomer (a2) can be, for example, 30 / 70 to 70 / 30, or 40 / 60 to 60 / 40.

[0031] The photopolymerization initiator (B) contained in the photocurable resin is, for example, acetophenone compounds, benzoin compounds, benzophenone compounds, thioxanthone compounds, anthraquinone compounds, acylphosphine oxide compounds, 3,3',4,4'-tetra(tert-butyloperoxycarbonyl)benzophenone, acrylic benzophenone, etc. Examples of acetophenone compounds are 4-phenoxydichloroacetophenone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, 4-(2-hydroxyethoxy)-phenyl(2-hydroxy-2-propyl)ketone, 2-methyl-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2,2-dimethoxy-2-phenylacetophenone, etc. Benzoin compounds include, for example, benzoin, benzoin methyl ether, benzoin isoethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether. Benzophenone compounds include, for example, benzophenone, benzoyl benzoic acid, benzoyl methyl benzoate, 4-phenylbenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, and 3,3'-dimethyl-4-methoxybenzophenone. Thioxanthone compounds include, for example, thioxanthone, 2-chlorothioxanthone, 2,4-dichlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, isopropylthioxanthone, and 2,4-diisopropylthioxanthone. Examples of anthraquinone compounds include 4,4'-dimethylaminothioxanthone (also known as mineral ketone), 4,4'-diethylaminobenzophenone, α-acyloxime ester, benzyl, methylbenzoyl formate ("ViaCure 55"), and 2-ethylanthraquinone. Examples of acylphosphine oxide compounds include 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.These photopolymerization initiators (B) can be used individually or in combination of two or more.

[0032] From the viewpoint of rapid curing and thick film curing properties, the content of the photopolymerization initiator (B) in the photocurable resin may be, for example, 0.1 parts by mass or more and 3 parts by mass or 0.1 parts by mass or more and 2 parts by mass per 100 parts by mass of resin component (A). The photocurable resin contains resin component (A) and photopolymerization initiator (B), but may also contain various additives as needed. Examples of additives include polymerization inhibitors, antioxidants, light stabilizers, solvents, defoamers, thixotropes, sensitizers, leveling agents, tackifiers, antistatic agents, flame retardants, curing accelerators, pigments, fillers, reinforcing materials, aggregates, etc.

[0033] The unsaturated polyester resin contained in thermosetting resins is, for example, a reaction product of a polybasic acid component and a polyhydric alcohol component. The polybasic acid component is, for example, an essential component of α,β-ethylenically unsaturated dibasic acid (I) and terephthalic acid (II). The polyhydric alcohol component is, for example, an essential component of neopentyl glycol (III) and ethylene glycol (IV).

[0034] The α,β-ethylenically unsaturated dibasic acid (I) is, for example, maleic acid, fumaric acid, or chlormaleic acid. The α,β-ethylenically unsaturated dibasic acid (I) may also be an acid anhydride of maleic acid, an acid anhydride of fumaric acid, or an acid anhydride of chlormaleic acid. The polybasic acid component may be a saturated dibasic acid different from terephthalic acid (II). Examples of such saturated dibasic acids include isophthalic acid, phthalic acid, phthalic anhydride, nitrophthalic acid, tetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, halogenated phthalic anhydride, oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, etc., and their acid anhydrides. The above saturated dibasic acid may be used in combination with terephthalic acid as needed.

[0035] The polyhydric alcohol component may include, for example, neopentyl glycol (III) and ethylene glycol (IV), as well as other polyhydric alcohols. Examples of such other polyhydric alcohols include diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, trimethylolpropane, and hydrogenated bisphenol A. The amount of polyhydric alcohol component is between 1.0 mole and 1.2 moles per mole of the polybasic acid component.

[0036] The weight-average molecular weight of the unsaturated polyester resin (determined using gel permeation chromatography on a standard polystyrene basis, the same applies hereinafter) may be between 8,000 and 50,000, or between 10,000 and 45,000. The acid value of the unsaturated polyester resin may be between 3KOH mg / g and 35KOH mg / g, or between 5KOH mg / g and 30KOH mg / g.

[0037] Unsaturated polyester resins are used, for example, by dissolving them in polymerizable monomers. Examples of polymerizable monomers include aromatic vinyl monomers, alkyl methacrylates, alkyl acrylates, methacrylates of polyhydric alcohols, diallyl phthalates, triallyl cyanurates, and acrylonitrile. Examples of aromatic vinyl monomers include styrene, vinyltoluene, α-methylstyrene, chlorostyrene, dichlorostyrene, divinylbenzene, and t-butylstyrene. Examples of alkyl methacrylates include methyl methacrylate, ethyl methacrylate, and butyl methacrylate. Examples of alkyl acrylates include methyl acrylate, ethyl acrylate, and butyl acrylate. Examples of methacrylates of polyhydric alcohols include neopentyl glycol dimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentamethacrylate, and dipentaerythritol hexamethacrylate. Examples of polyhydric alcohol methacrylates include neopentyl glycol diacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate. From a cost perspective, styrene may be used as the polymerizable monomer.

[0038] The fibers are dispersed or woven into the lining material 20 and include, for example, polyvinyl alcohol fibers, polyamide fibers, polyethylene fibers, polypropylene fibers, polyester fibers, polyarylate fibers, ultra-high molecular weight polyethylene fibers, polyaramid fibers, carbon fibers, glass fibers, and liquid crystal polyester fibers. In this embodiment, glass fiber reinforcement is used as the fiber. Examples of the glass fiber reinforcement include roving cloth, chopped strand mat, unidirectional sheet, multiaxial stitch base material, and stitch mat. Roving cloth is made by plain weaving roving. Chopped strand mat is a nonwoven fabric obtained by fixing randomly oriented 2-inch chopped strands with a binder. A unidirectional sheet is made by aligning multiple rovings in the same direction and integrating them with auxiliary weft threads, binders, etc. A multiaxial stitch base material is made by laminating sheets aligned in one direction in multiple directions and integrating them with stitch threads. Stitch mats are made by stitching together sheet material aligned in one direction with randomly oriented chopped strands. The above-mentioned glass fiber reinforced material can be used alone or in combination of two or more types.

[0039] Glass fibers are obtained from raw materials such as alkali-containing glass (C glass), low-alkali glass, and alkali-free glass (E glass). From the viewpoint of infrastructure repair applications (mechanical properties, corrosion resistance, etc.), acid-resistant glass (ECR glass) may be used as the glass fiber. From the viewpoint of mechanical properties, the fiber content in the lining material 20 may be 20% by mass or more and 70% by mass or 30% by mass or more and 60% by mass or less.

[0040] The tubular outer covering material 30 is a tubular member for protecting the lining material 20 during transportation of the rehabilitation pipe 1, during the laying of the rehabilitation pipe 1 on the existing pipe 100, etc. It is flexible and covers the outer surface 20b. The tubular outer covering material 30 defines the outer surface of the rehabilitation pipe 1. The tubular outer covering material 30 has, for example, water resistance, abrasion resistance, heat resistance, etc. From the viewpoint of preventing water from reaching the lining material 20 during the laying of the rehabilitation pipe 1 on the existing pipe 100, the tubular outer covering material 30 may be impermeable to water. The tubular outer covering material 30 is, for example, a tubular molded body of a known resin film. Unlike the cover film 10, the tubular outer covering material 30 functions as the outer surface of the rehabilitation pipe 1 even after the rehabilitation pipe 1 has been laid on the existing pipe 100. The resin film constituting the tubular outer casing 30 is, like the cover film 10, for example, a urethane elastomer film, a polyamide film, a polyethylene terephthalate film, a polyester elastomer film, etc. The tubular outer casing 30 may be a tube with a single-layer structure or a tube with a multi-layer structure, similar to the cover film 10.

[0041] Sensor 40 is a device that measures the electrical properties of the surface of the lining material 20 and is in contact with the outer circumferential surface 20b of the lining material 20. By detecting changes in the electrical properties of the lining material 20 using sensor 40 during the laying of the rehabilitated pipe 1, it is possible to accurately determine whether or not the outer circumferential surface 20b of the lining material 20 has hardened. Changes in the electrical properties of the lining material 20 are detected, for example, by an external device (measuring device) electrically connected to sensor 40. For this reason, although not shown in the figures, the rehabilitated pipe 1 may have terminals, wiring, etc. for connecting sensor 40 and the external device. In one example, sensor 40 is provided at the outlet end (not shown) of the tubular outer covering material 30. This outlet end is the end located downstream of the existing pipe 100 in direction X when the rehabilitated pipe 1 is laid on the existing pipe 100. In this case, the external device or the wiring connected to the external device may be in direct contact with sensor 40. If the rehabilitation pipe 1 has the above-mentioned terminal, the terminal is located, for example, at the outlet end or the inlet end (not shown) of the tubular outer covering material 30.

[0042] The electrical properties measured by the sensor 40 are, for example, at least one of the following: electrical resistance, impedance, capacitance, absolute dielectric constant, dielectric loss, phase difference, and ionic viscosity of the outer surface 20b of the lining material 20. The above electrical properties change depending on whether or not the lining material 20 has hardened. In particular, the ionic viscosity of the lining material 20 changes significantly due to the hardening of the lining material 20 (i.e., the change from liquid or gel to solid). On the other hand, after the lining material 20 has hardened, the change in ionic viscosity is small. For this reason, from the viewpoint of accurately detecting the degree of hardening of the outer surface 20b of the lining material 20, the sensor 40 may measure at least the ionic viscosity of the outer surface 20b of the lining material 20. Note that ionic viscosity is the reciprocal of ionic conductivity and can also be used as an indicator of the degree of hardening.

[0043] In this embodiment, the sensor 40 is located between the lining material 20 and the tubular outer covering material 30 in the radial direction of the rehabilitated pipe 1. In one example, when the rehabilitated pipe 1 is laid on an existing pipe 100, the sensor 40 is located above the central axis (not shown) of the rehabilitated pipe 1, but is not limited to this. The sensor 40 may be located at the top of the lining material 20 or at the bottom of the lining material 20. The sensor 40 has, for example, a thin shape. In this case, the presence of the sensor 40 is less likely to be a problem during the laying work of the rehabilitated pipe 1.

[0044] Figure 3 is a schematic diagram showing an example of the specific shape of the sensor according to this embodiment. As shown in Figure 3, the sensor 40 has a pair of electrodes 41 and 42 that contact the outer circumferential surface 20b of the lining material 20 and measure the electrical properties of the lining material 20. The pair of electrodes 41 and 42 are conductive members spaced apart from each other. In one example, each of the electrodes 41 and 42 has a comb-like shape. In this case, the electrical properties of the lining material 20 located between the electrodes 41 and 42 are detected. Each of the electrodes 41 and 42 is made of, for example, metal or an alloy. From the viewpoint of being located inside the rehabilitation pipe 1, the electrodes 41 and 42 may have corrosion resistance.

[0045] The electrodes 41 and 42 only need to be in contact with the outer circumferential surface 20b of the lining material 20. In one example, the electrodes 41 and 42 may be embedded in the lining material 20 from the outer circumferential side. In another example, the pair of electrodes 41 and 42 may be attached to the inner circumferential surface 30a of the tubular outer covering material 30. In this case, the pair of electrodes 41 and 42 may be formed on the inner circumferential surface 30a. A conductor that functions as the pair of electrodes 41 and 42 may be printed on the inner circumferential surface 30a. In this case, the position of the sensor 40 inside the rehabilitation pipe 1 can be fixed.

[0046] Electrodes 41 and 42 each have bases 41a and 42a extending in a direction perpendicular to direction X. Electrode 41 also has a plurality of protrusions 41b extending along direction X from base 41a toward base 42a, and electrode 42 has a plurality of protrusions 42b extending along direction X from base 42a toward base 41a. The base 41a and the plurality of protrusions 41b are integrated with each other, and the base 42a and the plurality of protrusions 42b are integrated with each other. At least one of the bases 41a and 42a may extend in direction X or in a direction intersecting direction X. At least one of the protrusions 41b and 42b may extend in a direction intersecting direction X or in a direction perpendicular to direction X.

[0047] Next, an example of a method for laying a rehabilitation pipe according to this embodiment will be described in detail with reference to Figure 4. Figure 4 is a flowchart illustrating the method for laying a rehabilitation pipe.

[0048] First, a tubular structure, which will later become the rehabilitated pipe 1, is placed inside the existing pipe 100 (first step ST1). In the first step ST1, a tubular structure is first prepared, which is manufactured by a known method and has a cover film 10, a tubular lining material 20, a tubular outer covering material 30 that covers the outer surface 20b of the lining material 20, and a sensor 40 that is in contact with the outer surface 20b of the lining material 20. For example, in the manufacture of the tubular structure, the sensor 40 is placed between the lining material 20 and the tubular outer covering material 30 at a predetermined timing.

[0049] Next, the tubular structure is placed inside the existing pipe 100 by a known method. Subsequently, the gap between the tubular structure and the existing pipe 100 is filled by expanding the tubular structure. The expansion of the tubular structure ensures contact between the outer surface 20b of the lining material 20 and the sensor 40.

[0050] Next, after the first step ST1, the lining material 20 is cured (second step ST2). If the lining material 20 is thermosetting, the tubular structure (especially the lining material 20) is heated using a known method that utilizes the heat source described above. This causes the lining material 20 to be thermosetting. If the lining material 20 is photocurable, light irradiation of the tubular structure (especially the lining material 20) is performed using a light source described above. This causes the lining material 20 to be photocured. In the second step ST2, while the lining material 20 is curing, the sensor 40 detects the electrical properties of the outer surface 20b of the lining material 20 and its vicinity. Based on the detection results of the sensor 40, it is determined that the curing of the lining material 20 is complete, and / or the curing conditions of the lining material 20 are adjusted. The cover film 10 may be peeled off from the lining material 20 before the second step ST2, or it may be peeled off from the lining material 20 after the second step ST2.

[0051] During the curing of the lining material 20 in the second step ST2, the sensor 40 detects changes in the electrical properties of the lining material 20. In one example, the sensor 40 detects a change in the ionic viscosity on the outer surface 20b of the lining material 20. In another example, if the change in the ionic viscosity of the lining material 20 is less than a predetermined value for a predetermined period (e.g., 1 minute), it may be determined that the outer surface 20b of the lining material 20 has sufficiently cured. In yet another example, if the ionic viscosity of the lining material 20 is still less than a predetermined value even after a predetermined time has elapsed from the start of the second step ST2, the curing conditions of the lining material 20 may be adjusted to accelerate the curing of the lining material 20. This makes it less likely for curing defects to occur on the outer surface 20b of the lining material 20. It also shortens the curing time of the lining material 20. The curing conditions can be adjusted by, for example, the flow rate, inflow time, and / or temperature of the hot water or steam supplied into the tubular structure, and the intensity of the light (light source output) irradiated onto the lining material 20.

[0052] In one example, in the second step ST2, the curing of the lining material 20 is completed faster the closer it is to the inlet end of the tubular exterior material 30. Specifically, first, a device for curing the lining material 20 (for example, a light source) is installed inside the tubular structure from the inlet end of the tubular exterior material 30. Next, the device is moved toward the outlet end of the tubular exterior material 30. In this case, the timing of the completion of the overall curing of the lining material 20 can be accurately determined by using the detection results of a sensor 40 located at the outlet end of the tubular exterior material 30. Adjusting the curing conditions of the lining material 20 also includes adjusting the position of the light source and adjusting the speed at which the light source moves.

[0053] According to the method for laying the rehabilitated pipe 1 according to this embodiment described above, in the second step ST2, the electrical characteristics of the outer surface 20b of the lining material 20 are directly detected by the sensor 40. That is, the electrical characteristics of the outer surface 20b can be detected selectively and accurately. Based on the detection result of the sensor 40, it is determined that the lining material 20 has completed curing, and / or the curing conditions of the lining material 20 are adjusted. By utilizing the detection result of the sensor 40, it is possible to accurately determine that the lining material 20 has sufficiently cured up to the outer surface 20b. Furthermore, by adjusting the curing conditions of the lining material 20 based on the detection result of the sensor 40, it becomes easier to sufficiently cure the lining material 20 up to the outer surface 20b. For this reason, the above-described method using the rehabilitated pipe 1 according to this embodiment makes it possible to prevent curing defects of the lining material 20.

[0054] Furthermore, in this embodiment, the detection results of the sensor 40 allow for accurate determination of the time and energy required for sufficient hardening of the entire lining material 20 (especially the outer surface 20b). This reduces the use of excessive energy during the laying of the rehabilitation pipe 1 while optimizing the laying period of the rehabilitation pipe 1. Therefore, the use of the rehabilitation pipe 1 improves the laying efficiency of the rehabilitation pipe 1. In addition, if the sensor 40 has a thin shape, the presence of the sensor 40 is less likely to be a problem during the laying work of the rehabilitation pipe 1. Here, sensors that utilize comb-shaped electrodes, such as electrodes 41 and 42, are usually used to measure members with a thickness on the order of μm (micro-field). However, in this embodiment, the sensor 40 is applied to the lining material 20, which is considered thin-walled with a thickness of several mm (macro-field). The sensor 40 can accurately detect whether or not the outer surface 20b of the lining material 20 has hardened by measuring at least the ionic viscosity on the outer surface 20b of the lining material 20.

[0055] In one example, each of the electrodes 41 and 42 may have a comb-like shape. In this case, changes in the electrical properties on the outer surface 20b of the lining material 20 can be detected with high accuracy.

[0056] In one example, electrodes 41 and 42 may be attached to the inner circumferential surface 30a of the tubular outer material 30. In this case, the respective positions of electrodes 41 and 42 in the rehabilitation pipe 1 are less likely to change.

[0057] In one example, the sensor 40 may be installed at the outlet end of the tubular outer material 30. In this case, it is possible to accurately determine that the entire rehabilitation pipe 1 has hardened sufficiently. In addition, since the connection between the sensor 40 and the external device is made easier, the installation work of the rehabilitation pipe 1 is less likely to become complicated.

[0058] The following describes a modified version of the above embodiment and a method for laying the rehabilitation pipe. In the description of the modified version, explanations that overlap with the above embodiment will be omitted.

[0059] Figure 5 is a schematic perspective view showing a modified rehabilitation pipe positioned inside an existing pipe. As shown in Figure 5, the modified rehabilitation pipe 1A is equipped with two or more sensors 40. The two or more sensors 40 are spaced apart from each other and aligned in direction X. The pitch of the two or more sensors 40 in direction X may be constant or different. When the rehabilitation pipe 1A is laid in the existing pipe 100, the positions of the sensors 40 in the direction perpendicular to direction X may be the same or different. For example, each sensor 40 may be located above the central axis (not shown) of the rehabilitation pipe 1. Some sensors 40 may be located at the top of the lining material 20, and other sensors 40 may be located at the bottom of the lining material 20. For example, if the rehabilitation pipe 1A has two sensors 40, one may be provided at the outlet end of the tubular exterior material 30, and the other at the inlet end of the tubular exterior material 30. If the rehabilitation pipe 1A has terminals and wiring corresponding to each sensor 40, all of these terminals may be located at the outlet end or at the inlet end. In the second step of the method for laying the rehabilitation pipe 1A according to the modified example, the position of the device (light source) inside the existing pipe 100 may be adjusted based on the detection results of two or more sensors 40.

[0060] In the modified configuration described above, the same effects and advantages as in the above embodiment are achieved. In addition, by utilizing the detection results of two or more sensors 40, the energy required for laying the rehabilitation pipe 1A can be reduced.

[0061] A method for laying a rehabilitation pipe and a rehabilitation pipe relating to one aspect of this disclosure are as described in [1] to [9] below, for example, and these have been described in detail based on the above embodiments and modifications. [1] A first step involves placing a tubular structure, which is tubular in shape and contains a curable resin, and has a sensor in contact with the outer surface of the lining material, inside an existing pipe. After the first step, a second step is taken to cure the lining material, Equipped with, The sensor has a pair of electrodes that are in contact with the outer surface and measure the electrical properties of the lining material. In the second step, based on the detection result of the sensor, it is determined that the curing of the lining material is complete, and / or the curing conditions of the lining material are adjusted. Method of laying rehabilitation pipes. [2] The method for laying a rehabilitated pipe according to [1], wherein the lining material is heat-cured or light-cured in the second step. [3] The method for laying a rehabilitated pipe according to [1] or [2], wherein each of the pair of electrodes is comb-shaped. [4] The tubular structure has two or more of the sensors, Two or more of the sensors are spaced apart from each other and arranged in the direction of the long axis of the tubular structure. The method for laying a rehabilitated pipe according to any one of [1] to [3], wherein the hardening conditions of the lining material are adjusted in the second step based on the detection results of two or more of the sensors. [5] A tubular lining material containing a curable resin, A sensor in contact with the outer surface of the lining material, Equipped with, The sensor has a pair of electrodes that are in contact with the outer surface and measure the electrical properties of the lining material. Rehabilitation pipe. [6] The method for laying a rehabilitated pipe according to [5], wherein each of the pair of electrodes is comb-shaped. [7] The lining material further comprises a tubular outer covering material that covers the outer surface of the lining material, The rehabilitation tube according to [5] or [6], wherein the pair of electrodes are attached to the inner circumferential surface of the tubular outer material. [8] The sensor is provided at the outlet end of the tubular outer material, and the rehabilitation pipe is as described in [7]. [9] The system comprises two or more of the aforementioned sensors, The rehabilitation pipe according to any one of [5] to [8], wherein two or more of the sensors are spaced apart from each other and arranged in the direction of the long axis of the rehabilitation pipe.

[0062] The method for laying a rehabilitation pipe and the rehabilitation pipe itself relating to this disclosure have been described above. However, the method for laying a rehabilitation pipe and the rehabilitation pipe itself relating to this disclosure are not limited to the embodiments and modifications described above, and may be modified within the scope of the gist described in the claims. For example, the configuration, shape, size, material, number, arrangement, etc., of the rehabilitation pipe relating to this disclosure can be appropriately changed within the scope of the gist described above.

[0063] In the above embodiments and modifications, the tubular structure that will later become a rehabilitated pipe and the rehabilitated pipe each have a cover film, lining material, tubular outer covering material, and a sensor, but are not limited to these. The tubular structure and the rehabilitated pipe each only need to have at least a lining material and a sensor. In one example, the tubular structure and the rehabilitated pipe each may have either a cover film or a tubular outer covering material in addition to the lining material and a sensor. Alternatively, the tubular structure may have a tubular member that functions as a tubular outer covering material before being laid on the existing pipe and as a cover film when being laid on the existing pipe, in addition to the lining material and a sensor. Such a tubular structure is used in a method of laying a rehabilitated pipe that employs an inversion method. In the case of a tubular structure having a tubular member that functions as a tubular outer covering material before being laid on the existing pipe, the sensor contacts the inner surface of the lining material before being laid on the existing pipe and contacts the outer surface of the lining material when being laid on the existing pipe. In other words, in this disclosure, the sensor only needs to be in contact with the surface that ultimately functions as the outer surface of the lining material. [Examples]

[0064] The present disclosure will be further illustrated by the following examples, but the present disclosure is not limited to these examples.

[0065] (Method of manufacturing experimental samples) First, a four-necked flask equipped with a thermometer, stirrer, inert gas inlet, air inlet, and reflux condenser was prepared. Next, 181 parts by mass of ethylene glycol, 250 parts by mass of diethylene glycol, 123 parts by mass of neopentyl glycol, and 484 parts by mass of terephthalic acid were charged into the four-necked flask, and the flask was heated under a nitrogen stream. This allowed a dehydration condensation reaction to be carried out at an internal temperature of 220°C using a conventional method, and when the solid content acid value reached 1 (mgKOH / g), the internal temperature was cooled to 140°C. Next, 322 parts by mass of maleic anhydride were charged into the four-necked flask, and a dehydration condensation reaction was carried out by raising the internal temperature to 215°C, and when the solid content acid value reached 10 (mgKOH / g), 0.14 parts by mass of hydroquinone were added. The mixture was dissolved in styrene monomer to obtain an unsaturated polyester resin with an unsaturated polyester concentration of 60% by mass.

[0066] Next, 0.20 parts by weight of photopolymerization initiator (1) (manufactured by IGM RESINS BV, "Omnirad 651") and 0.20 parts by weight of photopolymerization initiator (2) (manufactured by IGM RESINS BV, "Omnirad 819") were added to 100 parts by weight of the obtained unsaturated polyester resin, and the mixture was then mixed using a motor-powered stirring blade to obtain a resin composition.

[0067] Furthermore, a chopped strand mat (product name: "MC 450 A-303SC" manufactured by Nitto Boseki Co., Ltd.) was prepared as the base material. Next, six 100mm x 100mm squares were cut from the chopped strand mat, and a total of approximately 50g of resin composition was impregnated into them using a de-aerating roller. As a result, a laminate (thickness: approximately 5mm) to be used as the experimental sample was obtained. In the following, the surface of the laminate corresponds to the main surface of the laminate that does not come into contact with the glass plate described later, and is the part that is most susceptible to the effects of light irradiation described later. The back surface of the laminate corresponds to the main surface of the laminate that comes into contact with the glass plate described later, and is the part that is least susceptible to the effects of light irradiation described later.

[0068] (Hardening confirmation test of experimental samples) First, a flexible sensor (IDEX sensor, manufactured by NETZSCH JAPAN Co., Ltd.) connected to a dielectric constant measuring device (DEA288, manufactured by NETZSCH JAPAN Co., Ltd.) was mounted on a glass plate. Next, the laminated material, which was the experimental sample, was placed on the glass plate so that it was in close contact with the flexible sensor. Then, a metal halide lamp was used to illuminate the top of the laminated material at an illuminance of 10 mW / cm². 2 The material was irradiated with light (illuminance meter: Topcon Corporation, "UVR-T2 (main unit)", "UD-T40T2 (light receiving unit)"). During light irradiation with a metal halide lamp, the electrical properties of the laminate were measured using a flexible sensor and a dielectric constant measuring device. After 25 minutes of the above light irradiation, a plate-shaped cured material measuring 100 mm in length, 100 mm in width, and 5 mm in thickness was obtained.

[0069] Furthermore, the temperature, dielectric constant (ionic viscosity), surface Barcol hardness, and back surface Barcol hardness of the laminate were measured from the start of light irradiation up to 25 minutes later. Table 1 below shows the detection results for the ionic viscosity, surface Barcol hardness, and back surface Barcol hardness of the laminate at light irradiation times of 5 minutes, 10 minutes, 15 minutes, 20 minutes, and 25 minutes. In addition, Table 1 below also shows the ionic viscosity of the laminate before light irradiation (i.e., at a light irradiation time of 0 minutes). The surface Barcol hardness of the laminate was measured at five arbitrary points on the surface of the laminate using a Barcol hardness tester (BARBER COLMAN, "GYZJ934-1"). The back surface Barcol hardness was measured at five arbitrary points on the back surface of the laminate using a Barcol hardness tester (BARBER COLMAN, "GYZJ934-1").

[0070] Figure 6 shows the temperature and ionic viscosity changes of the laminate with respect to light irradiation time. In Figure 6, the horizontal axis represents light irradiation time, one vertical axis represents ionic viscosity, and the other vertical axis represents temperature. In Figure 6, graph 51 shows the temperature change of the laminate with respect to light irradiation time, and graph 52 shows the change in ionic viscosity of the laminate with respect to light irradiation time. As shown in Figure 6, it was confirmed that the ionic viscosity of the laminate hardly changed after about 15 minutes of light irradiation. From this result, it can be inferred that the curing of the laminate was completed after about 15 minutes of light irradiation. In addition, the difference between the ionic viscosity of the laminate before light irradiation and the ionic viscosity of the laminate after 15 minutes of light irradiation was 3 or more (i.e., there was a difference of more than two orders of magnitude in ionic viscosity). Furthermore, Table 1 below confirms that the surface Barcol hardness and back surface Barcol hardness of the laminate were both 45-55 after about 15 minutes of light irradiation. On the other hand, when the light irradiation time was less than 15 minutes, the Barcol hardness on the back surface of the laminate was not 45-55. From these results, it can be said that by checking the ionic viscosity change, which is least affected by light irradiation in the laminate, it is easy to determine whether the entire laminate has hardened sufficiently.

[0071] [Table 1] [Explanation of symbols]

[0072] 1,1A...Rehabilitated pipe, 10...Cover film, 20...Lining material, 20a...Inner surface, 20b...Outer surface, 30...Tubular outer covering material, 30a...Inner surface, 40...Sensor, 41...Electrode, 41a...Base, 41b...Protruding part, 42...Electrode, 42a...Base, 42b...Protruding part, 100...Existing pipe, ST1...First process, ST2...Second process, X...Direction.

Claims

1. A first step involves placing a tubular structure, which is tubular in shape and contains a curable resin, and has a sensor in contact with the outer surface of the lining material, inside an existing pipe. After the first step, a second step is taken to harden the lining material, Equipped with, The sensor has a pair of electrodes that are in contact with the outer surface and measure the electrical properties of the lining material. In the second step, based on the detection result of the sensor, it is determined that the curing of the lining material is complete, and / or the curing conditions of the lining material are adjusted. Method of laying rehabilitation pipes.

2. The method for laying a rehabilitated pipe according to claim 1, wherein the lining material is heat-cured or light-cured in the second step.

3. The method for laying a rehabilitated pipe according to claim 1 or 2, wherein each of the pair of electrodes has a comb-like shape.

4. The tubular structure has two or more of the sensors, Two or more of the sensors are spaced apart from each other and arranged in the direction of the long axis of the tubular structure. The method for laying a rehabilitated pipe according to claim 1 or 2, wherein in the second step, the hardening conditions of the lining material are adjusted based on the detection results of two or more of the sensors.

5. A tubular lining material containing a curable resin, A sensor in contact with the outer surface of the lining material, Equipped with, The sensor has a pair of electrodes that are in contact with the outer surface and measure the electrical properties of the lining material. Rehabilitation pipe.

6. The rehabilitation tube according to claim 5, wherein each of the pair of electrodes has a comb-like shape.

7. The lining material further comprises a tubular outer covering material that covers the outer surface of the lining material, The rehabilitation pipe according to claim 5 or 6, wherein the pair of electrodes are attached to the inner circumferential surface of the tubular outer material.

8. The rehabilitation pipe according to claim 7, wherein the sensor is provided at the outlet end of the tubular outer material.

9. The system comprises two or more of the aforementioned sensors, The rehabilitation pipe according to claim 5 or 6, wherein two or more of the sensors are spaced apart from each other and arranged in the direction of the long axis of the rehabilitation pipe.

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