JP2014169409A - Cfrp structure and cfrp structure restoring device - Google Patents

Abstract

The present invention relates to a method of repairing a damaged part by injecting a repair agent into the damaged part from the outside of the CFRP, and to repair the damaged part accurately and efficiently, and a repair device for the CFRP structure. Offer.
A substrate 12 containing a carbon sheet, and an optical fiber 14 that communicates from one end side to the other end side of the substrate 12 and has a portion buried in the substrate 12 are provided. A restoration agent injection hole 15 is provided, which is open on at least one surface in the thickness direction. A reference light source is connected to one end of the optical fiber 14 and a sensor is connected to the other end. The optical fiber also serves as a light guide for photocuring the restoration agent filled in the damaged part of the substrate.
[Selection] Figure 1

Description

  The present invention relates to a CFRP structure that can be suitably used for self-repair of CFRP (Carbon Fiber Reinforced Plastic) and a repair device for the CFRP structure.

  Carbon Fiber Reinforced Plastic (CFRP), a type of composite material, combines the light weight of plastic with the high strength and high elasticity of CF, and is superior in specific strength and specific rigidity. Widely used in industry. CFRP is often molded and used as a laminate. CFRP laminates have high strength in the layers, but the interlaminar strength is somewhat weak, and delamination and cracks may occur when subjected to aging or external impacts. As delamination and cracks progress, the load cannot be applied to the entire CFRP, and fracture occurs at a load lower than that of a healthy material. Since it is very dangerous that peeling or cracking occurs during operation of the CFRP structure, a CFRP structure having a self-repairing function capable of automatically repairing peeling or cracking is required.

  As a self-repairing method of CFRP, there are a method using microcapsules (Non-Patent Documents 1 and 2) and a method using hollow glass fibers (Non-Patent Document 3). These are methods for repairing damage by causing a repair agent to flow out of microcapsules or hollow glass fibers embedded in CFRP as damage occurs. The methods using microcapsules or hollow glass fibers have a restoration agent embedded in the material in advance, and these methods have a problem that the amount of the restoration agent for repairing damage is insufficient. As a method of solving this problem, a method of repairing by injecting a repair agent into the damaged part from the outside of CFRP has been proposed (Non-Patent Document 4).

Special table 2011-518056 gazette

M. R. Kessler, S. R. White, Self-activated healing of delamination damage in woven composites, composites Part A 32 683-699, (2001). Hiroki Otsuki, Kiyoshi Tsujimo, Minoru Riki, Graduates of Gotoh Tsuchimin Lectures on Mechanical Materials and Materials Processing Technology 2007 (15), 351-352, 2007-11-16. G. Williams, R. Trask, I. Bond, Aself-healing carbon fiber reinforced polymer for aerospace applications, composites Part A 38 1525-1532, (2007). Arao Keinobu, Minoru Minoru, Kiyoshi Tsujimo, Hokuriku Shin-Etsu Student Association 40th Student Graduation Research Presentation Lecture 701, (2011).

The method of repairing by injecting a repair agent into the damaged part from the outside of the CFRP can inject the repair agent continuously into the damaged part, and can overcome the shortage of the repair agent in the case of microcapsule method etc. However, in this method, after injecting the repair agent from the outside of the CFRP, a long-time after-curing is required to cure the repair agent, or a two-component mixed type repair agent is used. In such a case, there is a problem that handling properties are poor because the restoration agent begins to cure from the time when the resin and the curing agent are mixed.
The present invention relates to a method for repairing a damaged part of CFRP by a method of repairing by injecting a repair agent into the damaged part from the outside of the CFRP, and more accurately and efficiently repairing compared to the conventional method. An object of the present invention is to provide a CFRP structure that can be used and a repair device for the CFRP structure.

  A CFRP structure according to the present invention includes a substrate containing a carbon sheet, and an optical fiber that is connected from one end side to the other end side of the substrate and includes a portion buried in the substrate. The method is characterized in that a restoration agent injection hole is provided that opens on at least one surface in the thickness direction of the substrate. The number of carbon sheets stacked on the substrate incorporating the carbon sheet is not limited. Further, the thickness, size, and shape of the substrate are not limited.

The restoration agent injection hole provided in the CFRP structure may be a through-hole penetrating the substrate in the thickness direction. However, in order to accurately fill the restoration site with the restoration agent, the thickness of the substrate It is good to set it as the form which opens on one surface of a horizontal direction, and closes on the other surface.
The optical fiber is arranged in parallel with the substrate surface of the substrate, and the method of arranging the optical fiber so as to have a portion buried over the entire length from one end side to the other end side of the substrate is easily embedded in the substrate. There is an advantage that a damaged portion generated in the substrate can be easily detected.
Further, the optical fiber can be configured to include a portion buried in a direction intersecting with the substrate surface. This configuration has an advantage that, in the case of a CFRP substrate in which a large number of carbon sheets are laminated, it becomes easy to specify a damaged portion in the inner layer of the substrate, and repair in the inner layer of the substrate can be easily performed.

Further, a repair device according to the present invention includes a substrate incorporating a carbon sheet, and an optical fiber having a portion that is communicated from one end side to the other end side of the substrate and buried in the substrate, Is a repair device that uses a CFRP structure provided with an injection hole for a repair agent that opens on at least one surface in the thickness direction of the substrate, and repairs a damaged portion in the CFRP structure. As a detection mechanism for detecting the damaged portion, a light source connected to one end of the optical fiber, a sensor connected to the other end of the optical fiber, and a reference light from the light source to the optical fiber, And a control unit for identifying a damaged part generated in the substrate from the optical signal received by the sensor.
Further, as a repair device for the CFRP structure, as a repair mechanism for repairing the damaged part, a light source connected to the optical fiber, an injection mechanism for injecting a repair agent from the injection hole into the damaged part of the substrate, A thing provided with the control part which photocures the restoration agent by radiating light through the optical fiber to the restoration agent inject | poured into the damaged part can be used conveniently.

In addition, the CFRP structure is preliminarily defined by setting a repair range for each unit at the time of repair operation, and the detection mechanism includes a control unit that monitors each unit, thereby causing damage to the CFRP structure. The location can be detected accurately and efficiently.
Further, the CFRP structure is set in advance by dividing the repair range at the time of repair operation for each unit, and the repair mechanism includes a control unit that repairs each unit so that the CFRP structure can be accurately and It can be repaired efficiently.
A photo-curing resin is used for the restoration agent. The photo-curing resin is not limited to the UV-curing resin, and a photo-curing resin that is cured by various kinds of light can be used. The UV curable resin has high hardness, and the CFRP structure can be repaired reliably and efficiently by using the UV curable resin as a restoration agent and using the UV light source as a light source connected to the optical fiber.

  According to the CFRP structure and the CFRP structure repairing apparatus according to the present invention, it is possible to accurately detect a damaged portion generated in the CFRP structure and repair the damaged portion reliably and efficiently.

It is sectional drawing which shows the structural example of the CFRP structure which concerns on this invention. It is explanatory drawing which shows the self-repair method using a CFRP structure. It is explanatory drawing which shows the other example of a CFRP structure. It is explanatory drawing which shows the example which systematized the method of repairing a CFRP structure. It is explanatory drawing which shows the method of producing a test piece. It is the top view (a) and side view (b) of the test piece which attached the block for a test. It is explanatory drawing which shows the repair method of the test piece of CFRP structure. It is a schematic diagram of a DCB test. It is a Load-COD diagram about the test piece using an epoxy resin and an ultraviolet curable resin. It is a Load-COD diagram about a specimen before restoration and after restoration. It is explanatory drawing which shows the state of the repair part of a test piece. It is a photograph of the restoration part of the test piece after restoration. It is a photograph of the restoration part of the test piece after restoration. It is a photograph of the restoration part of the test piece after restoration.

(Configuration of CFRP structural material)
FIG. 1 shows a configuration example of a CFRP structure used in the CFRP self-repairing method according to the present invention. A CFRP structure 10 shown in FIG. 1 includes a substrate 12 made of carbon fiber plastic (CFRP), and an optical fiber 14 embedded continuously in the inner layer of the substrate 12 over the entire length in the longitudinal direction of the substrate 12 in parallel to the substrate surface. With.

The optical fiber 14 embedded in the CFRP structure 10 is a component of a detection mechanism that optically detects a damaged portion of the CFRP, and is also a component of a repair mechanism that repairs the damaged portion. Therefore, the optical fiber 14 is arranged at an arrangement interval that can reliably detect the damaged portion when the damaged portion is generated on the substrate 12.
FIG. 1 shows a state in which the substrate 12 is viewed from the cross-sectional direction. In the state in which the substrate 12 is viewed from the plane direction, a plurality of optical fibers 14 are arranged in parallel over the entire surface of the substrate 12 with a predetermined interval. In many cases, CFRP is formed as a laminated structure in which a plurality of carbon sheets such as carbon fiber cloth are laminated. Therefore, when it is necessary to detect a damaged portion at a different lamination position, a plurality of light beams are also provided in the lamination direction of the substrate 12. A fiber may be arranged.

The substrate 12 is provided with a restoration agent injection hole 15 in the thickness direction of the substrate 12. The injection hole 15 is for supplying a repairing agent to the damaged part during the repairing operation. The injection hole 15 has a bottomed hole shape with one side open and the other side closed. If the thickness of the bottom portion (closed portion) of the injection hole 15 is about the thickness of one carbon sheet (0.1 mm), the function of supplying the repairing agent to the damaged portion of the substrate 12 is not impaired.
The injection holes 15 are arranged at a predetermined interval in the plane of the substrate 12. The arrangement interval of the injection holes 15 is also assumed to cause damage to the substrate 12, and when the substrate 12 is damaged, the injection holes 15 are positioned at or near the damaged portion. Set so that restorative can be supplied. For example, the injection holes 15 are arranged like a lattice point arrangement in the plane of the substrate 12, and the arrangement interval of the injection holes 15 is set as appropriate.

  When the injection hole 15 is provided in the thickness direction of the substrate 12, it is necessary to prevent the strength of the CFRP structure 10 from being impaired. For this purpose, the hole diameter of the injection hole 15 and the arrangement position of the injection hole 15 are appropriately selected so as not to impair the strength of the CFRP structure 10. If a pin for forming injection holes (a tapered pin) is placed in advance in a mold that laminates carbon sheets and is resin-molded, the carbon sheet can be crossed with the carbon sheet during molding. A pin is inserted so as not to cut the carbon fiber, and the CFRP structure 10 can be manufactured without impairing the strength of the carbon sheet.

In the CFRP structure 10 shown in FIG. 1, an optical fiber 14 is embedded parallel to the substrate surface. As a method of arranging the optical fiber on the substrate 12, as shown in FIG. 3, it is also possible to arrange the optical fiber 16 so as to intersect with the inner carbon sheet layer of the substrate 13.
In the CFRP structural material 11 shown in FIG. 3, the optical fiber 16 is arranged along the substrate surface on the surface of the substrate 13 so as to intersect the carbon sheet layer inside the substrate 13, and the optical fiber 16 is bent as a whole. It is a form to do. The optical fiber 16 has a bent shape as a whole, but as a whole is a series of optical fibers.
In FIG. 3, the injection holes are not shown, but also in the CFRP structure 11, the repair agent injection holes are provided at predetermined planar arrangement intervals in the thickness direction of the substrate 13.

(Repair method using CFRP structure)
2A to 2D show a method of repairing the CFRP structure 10 using the CFRP structure 10 shown in FIG.
In order to detect damage occurring in the CFRP structure 10 using the optical fiber 14, a light source 20 for injecting light into the optical fiber 14 is connected to one end of the optical fiber 14, and light that has passed through the optical fiber 14 is connected to the other end. Is connected to the sensor 22. In order to connect the light source 20 and the sensor 22 to the optical fiber 14, both ends of the optical fiber 14 are slightly extended from the periphery of the substrate 12.
Whether or not the CFRP structure 10 has been damaged is detected based on whether or not the reference light can be sensed by the sensor 22 by passing reference light such as infrared light from the light source 20 through the optical fiber 14. A control unit that controls the optical fiber 14 and the light source 20 and the light source 20 and the sensor 22 and identifies a damaged portion of the substrate 12 from the optical signal constitutes a detection mechanism. The light source 20 may be a light source system unit that also serves as a control unit.

FIG. 2B shows a state where the CFRP structure 10 has been detected for some reason and is being detected. When damage such as cracking or delamination occurs in the CFRP structure 10, the optical fiber 14 is broken at the damaged portion. The change in the optical conduction state by the optical fiber 14 is detected by the sensor 22, and the position of the substrate 12 where the damage has occurred can be detected by the control unit. FIG. 2B shows a state in which a crack has occurred in part A of the substrate 12.
By disposing the optical fibers 14 at a predetermined interval in the thickness direction of the substrate 12 and in the plane, the position in the depth direction (Z position) and the position in the plane (XY position) of the damaged portion can be known.

  FIG. 2 (c) shows a state where the repairing agent 30 is injected from the pump 24 into the damaged part of the CFRP structure 10 to repair the damaged part (A part). As a method for repairing a damaged portion generated in the substrate 12, in this embodiment, a photocurable resin (ultraviolet curable resin) is used as a repairing agent 30 from the opening side of the injection hole 15 provided in the substrate 12 of the CFRP structure 10. A method of injecting and photocuring the photocurable resin from the light source 20 through the ultraviolet ray into the optical fiber 14 is used.

  Since the position of the damaged portion in the substrate 12 can be specified by optical sensing using the optical fiber 14, the light source 20, and the sensor 22, first, according to the damaged portion of the substrate 12 so that the repairing agent 30 does not leak outside the damaged portion. The shielding film is disposed on the substrate 12 with the periphery sealed on the surface of the substrate 12 where the injection hole 15 is open, and the inner space of the shielding film and the pump 24 are communicated with each other by a tube 25 or the like. Next, the photocurable resin is injected into the shielding film from the pump 24 through the tube 25, and the photocurable resin is injected into the injection hole 15.

The photocurable resin is injected into the substrate 12 from the injection hole 15 and enters the damaged portion of the substrate 12. Since the photocurable resin has good fluidity when not irradiated with ultraviolet rays, it penetrates into fine damaged portions.
After the restoration part 30 (photocurable resin) is filled in the damaged part, ultraviolet rays are injected from the light source 20 through the optical fiber 14. In the optical sensing, infrared light is input from the light source 20, but in the restoration operation, the infrared light is switched to ultraviolet light. The ultraviolet rays thrown into the optical fiber 14 are radiated from the end face where the optical fiber 14 is broken. Since the optical fiber 14 is broken at the damaged portion of the substrate 12, ultraviolet rays are selectively emitted to the damaged portion, and the photocurable resin in the damaged portion is intensively photocured.

FIG. 2D shows a state in which the photocurable resin that is the restoration agent 30 filled in the damaged portion of the substrate 12 is cured to repair the damage. In the present embodiment, the optical fiber 14, the injection mechanism of the repair agent 30 such as the pump 24 and the tube 25, and the ultraviolet light source 20 correspond to the repair mechanism of the damaged portion of the substrate 12. The restoration operation can be controlled by controlling the injection mechanism, the light source 20, and the like by the control unit.
The method of photocuring using ultraviolet rays has an advantage that the resin can be cured in a much shorter time than the resin curing method by after heating, and the damaged portion can be reliably repaired.

  In FIGS. 2A to 2D, the light source 20 and the sensor 22 are connected to one optical fiber 14, and ultraviolet rays are irradiated from the one optical fiber 14, but the CFRP structure is shown. 10, a plurality of optical fibers are juxtaposed both in the thickness direction of the substrate 12 and in the plane of the substrate 12, and in the optical sensing, a plurality of optical fibers 14 are sensed to damage the substrate 12. When the presence / absence is detected and damage is detected, the resin is cured by radiating ultraviolet rays from a plurality of optical fibers 14 related to the damaged part.

In the operation of curing the resin, since the damage range can be specified, in consideration of certainty, a range slightly wider than the damage range is set as a repair range in which the repair agent 30 is injected, and from the injection hole 15 within the repair range. The repair agent 30 is injected. The repairing agent 30 injected into the injection hole 15 at a position away from the damaged site does not have the effect of photocuring, but the repairing agent 30 is wasted by setting the repairing range limitedly. That can be suppressed.
According to the method of the present invention, by supplying the repairing agent 30 from the outside using the pump 24, a sufficient amount of the repairing agent 30 can be fed to a necessary portion, and the range in which the repairing agent 30 is injected (restoration range). ) Can be used to save the amount of the restoration agent 30 used.

  In the CFRP structure 11 shown in FIG. 3 described above, the optical fiber 16 is disposed so as to intersect the carbon sheet of the inner layer of the substrate 13. Also in this case, when damage occurs in the inner layer of the substrate 13, the optical fiber 16 is broken at the damaged portion, so that the damaged portion can be detected in the same manner as the method shown in FIG. When repairing the damaged part, a photocurable resin was injected from an injection hole near the damaged part, ultraviolet light was injected into the optical fiber 16 and ultraviolet light was emitted from the broken part of the optical fiber 16 to cause damage. It can be repaired by photocuring the photocurable resin at the site. This repair method is not fundamentally different from the repair method shown in FIG.

  FIG. 4 is a configuration example in a case where the repair operation of the CFRP structure 10 can be performed as a system. That is, the repair range is defined and set in advance so that the operation for repairing the CFRP structure 10 is performed in units, and the unit is repaired in units when the substrate is damaged. The control unit monitors whether or not damage has occurred for each unit, and when the unit area is damaged, performs a repair operation only in the unit area. If damage has occurred in a range that spans multiple units, then of course all repaired units are repaired.

  According to this method, when damage is detected by the control unit, it is not necessary to consider what range should be set as the repair range and perform the repair operation. Can be easily performed. If the repair range is common, there is also an advantage that the repair mechanism can be shared.

Hereinafter, the results of experiments on a method for self-repairing a CFRP substrate using the CFRP structure according to the present invention will be described.
(Manufacture of CFRP structure)
FIG. 5 shows the molding method of the test piece used in the experiment. The test piece was produced by using a carbon fiber cloth material as a carbon sheet and an epoxy resin as a base material, and molding by a VaRTM (Vacuum asisted Resin Transfer Molding) method. The number of layers of the carbon fiber cloth material 40 is 12, and a polyimide film 41 (thickness: 7.5 μm) is sandwiched between the 6 layers and 7 layers of the carbon fiber cloth material 40 to form an initial crack. The optical fiber 42 is embedded in a U shape so as to be disposed across the seven layers. The optical fiber 42 is a plastic optical fiber (diameter 0.5 mm). Three optical fibers 42 were arranged in parallel when viewed from the plane direction of the test piece.

  On the rubber plate 43, the net, peel cloth, carbon fiber cloth material 40, polyimide film 41, optical fiber 42, carbon fiber cloth material 40, net, peel cloth are overlapped in this order, and the whole is covered with the bag film 44. The peripheral edge of the film 44 is sealed with a sealant tape. A thumbtack 45 (needle diameter 0.8 mm) is inserted into the rubber plate 43 in order to form an injection hole for injecting the repair agent.

While sucking the bag film 44 with a vacuum pump, an epoxy resin is introduced into the bag film 44 to impregnate the resin into the carbon fiber cloth and between the layers. After impregnating the resin, the resin was allowed to stand for 24 hours to cure the resin. Thereafter, after-curing was performed at 55 ° C. for 6 hours.
A molded product obtained by resin molding was cut into a strip shape to obtain a test piece. The length, width, and thickness of the specimen are 140 mm, 25 mm, and 3 mm, respectively. A DCB test block was adhered to the test piece and used for the experiment.
6A is a plan view of a test piece provided with a test block 47, and FIG. 6B is a side view. Three optical fibers 42 are embedded in the test piece, and two injection holes 46 for injecting a restoration agent (ultraviolet curable resin) are formed. The test block 47 is bonded to the side of the test piece on which the polyimide film 41 is disposed.

(Test piece repair method)
The degree of repair of the test piece was evaluated by performing a DCB test on the test piece before repair and the test piece after repair, and measuring the strength of the test piece.
In the repair process, the polyimide film 41 was artificially removed from the test piece to cause a crack, and at the same time, the repair process was performed after the optical fiber 42 was broken (cut). Here, a method for repairing the test piece will be described.

FIG. 7 shows a method for repairing the test piece. The test piece to be repaired is obtained by cutting the polyimide film 41 from the end face side of the test piece with a sharp blade, artificially forming a crack B, and cutting the position where the optical fiber 42 intersects the polyimide film 41. The surface of the test piece is sealed with a sealant tape so as to communicate with the injection hole 46 of the test piece, and the film 50 and the tube are attached, and the syringe 51 is connected to the tube. An ultraviolet LED (wavelength: 375 nm) is connected to the optical fiber 42 as an ultraviolet light source.
A UV curable resin 52 is injected into the test piece from the injection hole 46 using the syringe 51, the UV LED is turned on, and the UV curable resin filled in the test piece from the broken portion of the optical fiber 42 through the optical fiber 42 is filled. The resin 52 is irradiated with ultraviolet rays. The ultraviolet irradiation time was 1 hour.

(DCB test)
Before the DCB test was performed on the test piece before repair and the test piece after repair, the mechanical properties of the epoxy resin of the base material of the test piece (CFRP) and the UV curable resin used for the repair were examined. This is because the difference in mechanical properties between the base material and the UV curable resin may affect the mechanical properties of the specimen before and after the repair. The comparison of the characteristics was performed by a method in which a DCB test was performed on a test piece obtained by bonding a strip-shaped acrylic plate with an epoxy resin and a test piece bonded with an ultraviolet curable resin to obtain a Load-COD diagram.
FIG. 8 shows a schematic diagram of the DCB test. In the DCB test, a load is applied to the test piece through the pin load block, and the relationship between the COD and the load P at that time is measured in correspondence with the crack length a to obtain a Load-COD diagram. .

FIG. 9 shows a Load-COD diagram for a test piece using an epoxy resin and an ultraviolet curable resin. The maximum load P _Ep of the test piece using the epoxy resin and the maximum load P _UV of the test piece using the ultraviolet curable resin are _defined as the adhesive strength of each resin.
The adhesive strength of the UV curable resin used in this experiment was 35.46% of the adhesive strength of the epoxy resin that is the base material of the test piece of the CFRP structure.

(Strength of specimen before repair)
Results of performing a DCB test on a CFRP structure specimen repaired by the method described above and obtaining a Load-COD diagram. FIG. 10 shows a diagram of a representative specimen (Before repair). In the DCB test, a polyimide film 41 as a test piece was cut from about 2 mm to 5 mm from the end side to form an initial crack.
In a normal DCB test, the load decreases as the crack progresses as indicated by the dashed arrow. When an optical fiber is embedded, the optical fiber is embedded in a direction in which a load is applied. Therefore, when the crack approached the optical fiber, the load increased as indicated by the solid arrow. This is due to the effect that the optical fiber applies a load.
In this experiment, the load at the time of crack growth before the influence of the optical fiber becomes significant is set as a load P _normal before repair. The place indicated by the circle in FIG. 8 is the load before repair.

(Strength of specimen after repair)
FIG. 10 also shows a Load-COD diagram obtained by performing a DCB test on the test piece repaired by artificially forming a crack as described above (Ater Repair).
Table 1 shows the measurement results of the load P _normal before _{repair and} the load P _repair after repair for seven samples. Table 1 also shows the result of calculating the _repair rate η = P _repair / P _normal (%) in order to evaluate the effectiveness of _repair .

  From Table 1, the repair rate of the repaired test piece is 9.94 (%) on average, and a certain repair effect by the repair method using the optical fiber and the ultraviolet curable resin is recognized. In this repair experiment, considering that the range in which the photocurable resin is cured by the ultraviolet rays emitted from the optical fiber 42 is limited to the vicinity of the end face of the optical fiber 42, the average repair rate is 9.94%. It can be said that it is not a low value.

(Observation of the repaired part of the specimen)
After the DCB test was performed on the test piece after repair, the repaired portion of the test piece was observed, and the ratio of the repaired portion and the range repaired by the ultraviolet curable resin was determined from the width of the test piece. FIG. 11 is an image diagram of a repaired portion. The test piece has three optical fibers arranged in parallel, and the width of the range cured by the light emitted from the optical fiber is B ₁ , B ₂ , and B ₃ (mm). The specimen width is B (mm), and the repair range is B ′ (%).
B ′ = (B ₁ + B ₂ + B ₃ ) / B

  12, 13, and 14 are surface photographs of the repaired portion of the test piece after the repair and the DCB test. The part represented by the circle is the part of the tip of the broken optical fiber, and the area surrounded by the line is the repaired part, that is, the area where the UV-curing resin that has been cured has been cured. . 12, 13, and 14, the X axis is the width direction of the test piece, and the Y axis is the length direction of the test piece.

The repair rate is considered to depend on the adhesive strength of the base material of the test piece and the repair agent (ultraviolet curable resin) and the repair range. From the above-mentioned adhesive strength between the base material of the test piece and the ultraviolet curable resin, P _Ep and P _UV , and the repair range, a conversion value η _CV (%) of the repair rate was determined by the following equation.
η _CV (%) = (P _UV / P _Ep ) × B ′
Table 2 shows the repair rate η obtained from the experiment and the converted value η _CV of the repair rate.

  As shown in Table 2, when the repair rate and the converted value were compared, the values were approximated. This shows that the adhesive strength between the base material and the restoration agent and the restoration range have a great influence on the restoration rate. Therefore, if a repairing agent having an adhesive strength equivalent to that of the base material is used and the repairing range can be made close to 100 (%), the repairing rate can be almost 100% although theoretically. This experimental result shows that the repair method according to the present invention can be effectively used as a method of repairing the damage of CFRP.

10, 11 CFRP structure 12, 13 Substrate 14, 16 Optical fiber 15 Injection hole 20 Light source 22 Sensor 24 Pump 30 Restoration agent 40 Carbon fiber cloth material 41 Polyimide film 42 Optical fiber 46 Injection hole

Claims (9)

A substrate containing a carbon sheet;
An optical fiber that communicates from one end side of the substrate to the other end side and that includes a portion buried in the substrate,
A CFRP structure, wherein the substrate is provided with a restoration agent injection hole that opens on at least one surface in the thickness direction of the substrate.   The CFRP structure according to claim 1, wherein the injection hole is opened on one surface in the thickness direction of the substrate and closed on the other surface.   3. The CFRP structure according to claim 1, wherein the optical fiber includes a portion that is arranged in parallel to the substrate surface of the substrate and is buried over the entire length from one end side to the other end side of the substrate.   The CFRP structure material according to claim 1, wherein the optical fiber includes a portion buried in a direction intersecting with the substrate surface. A substrate containing a carbon sheet; and an optical fiber that communicates from one end side to the other end side of the substrate and has a portion buried in the substrate, wherein the substrate includes at least one of the thickness directions of the substrate. A repair device for repairing a damaged portion generated in the CFRP structure using a CFRP structure provided with an injection hole for a repair agent that is opened on the surface of the CFRP structure,
As a detection mechanism for detecting the damaged part,
A light source connected to one end side of the optical fiber, a sensor connected to the other end side of the optical fiber, a reference light from the light source to the optical fiber, and an optical signal received by the sensor generated on the substrate A device for repairing a CFRP structure, comprising a control unit for identifying a damaged part. As a repair mechanism for repairing the damaged part,
A light source connected to the optical fiber, an injection mechanism for injecting a repair agent into the damaged portion of the substrate from the injection hole, and emitting light through the optical fiber to the repair agent injected into the damaged portion. The CFRP structure repair device according to claim 5, further comprising: a control unit that photocures the repair agent.   6. The CFRP structure according to claim 5, wherein the CFRP structure is set by dividing a repair range for each unit in advance, and the detection mechanism includes a control unit that monitors each unit. Body repair device.   7. The CFRP structure according to claim 6, wherein the CFRP structure is set by dividing a repair range for each unit in advance, and the repair mechanism includes a control unit that repairs each unit. Body repair device. The apparatus for repairing a CFRP structure according to any one of claims 5 to 8, wherein an ultraviolet curable resin is used as the restoration agent, and an ultraviolet light source is used as a light source connected to the optical fiber.