JP2003269090A - Construction method for preventing flaking of concrete - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To greatly reduce working time by shortening hardening time of a resin material and a curing term thereof, and enhance fire resistance efficiency. <P>SOLUTION: A construction method for preventing flaking of concrete is composed of a step for treating a section of the concrete, a step for treating a substrate surface of the concrete, a step for applying primer to the concrete, a step for applying a first intermediate coat to a concrete surface, a step for arranging a reinforcing material on the concrete surface, a step for applying a second intermediate coat on the concrete surface, and a step for applying a finishing coat to the concrete surface; a photosensitive resin is used for a part or the whole of a material for the intermediate coat and the finishing coat; the primer and the photosensitive resin are filled with a flame retarder; and the photosensitive resin is hardened by photoirradiation. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete lining part in a road or railway tunnel, a concrete balustrade or backside part of a highway or a railway viaduct, a chimney, a concrete wall of a high concrete, etc. Related to the exfoliation prevention method.

[0002]

2. Description of the Related Art A woven fabric, a knitted fabric, a mesh product, or a woven fabric, a knitted fabric, a mesh product, or There is a coating method for coating the surface of concrete with a three-dimensional knit as a reinforcement.
Here, the woven fabric, knitted fabric, meshed fabric, or three-dimensional knitted fabric is made of glass fiber, vinylon fiber, or the like, has a basis weight of about 100 to 1000 g / m ² , and has a thickness of 0.0.
A thin one of 5 to 0.60 mm is used. Also,
When the strength of the reinforcing material is insufficient, a plurality of reinforcing materials may be stacked and used. As a material used for coating, a resin material such as an epoxy resin, polymer cement, or the like is used, which is applied or sprayed.

A series of work contents will be described with reference to FIG. 1 by taking a case of using a resin material as an example. First, in the pre-treatment 1 of step S1, if there is a float on the concrete,
If there are exposed or rusted reinforcing bars, or if there are cracks, perform cross-section processing by the appropriate method. Then step S2
In the pre-treatment 2 of, the surface of the concrete is subjected to surface treatment by sanding or high-pressure washing (for example, 15 MPa),
Apply the primer to the concrete surface in step S3. In step S4, the first intermediate coating is performed, and in step S5, a reinforcing material such as a woven or knitted material, a mesh material, or a three-dimensional knitted material is attached and fixed. Then, the second intermediate coating is performed in step S6, and the final coating is performed in step S7. Depending on the construction method, an anchor pin may be provided to prevent the net from falling off so that the net does not peel off.

Here, the materials used for the primer, the intermediate coating, and the finishing are the permeability and adherence to concrete, the adherence to other coating materials, the penetration and adherence to reinforcing materials, and the weather resistance. , The materials (base compound and curing agent) suitable for each purpose and application are used. Also, the work of each step is subject to time constraints due to the previous process. For example, the work of step S6 is performed immediately after the work of step S5. The work of steps S3, S4, and S7 is provided with a curing period (reference time for splicing) between the work and the previous work. For example, when an epoxy resin material is used for the coating finish of step S6, if the temperature is 5 to 25 ° C., 7 days or more, 30 to 35
If it is ℃, leave a curing period of 3 days or more.

[0005]

By the way, in the case of applying the concrete exfoliation prevention method to transportation facilities such as roads and railroads, the road traffic interruption time should be as short as possible or without interruption. It would be convenient to be able to work in live line construction. Further, if it is a railway facility, it is necessary to efficiently proceed with the work within a short time during the night when there is no train operation, and it is strongly desired to shorten the work time.

However, in the above-mentioned conventional exfoliation prevention construction method, the construction method itself often repeats the same work many times, and a curing period is required between the works, so that the construction period becomes relatively long. Have

In addition, when fire resistance performance is required for the object to which the concrete exfoliation prevention method is applied, improvement in fire resistance performance is required.

The present invention solves the above-mentioned conventional problems. By shortening the curing time and curing period of the resin material, the working time can be greatly reduced and the fire resistance performance can be improved. It is an object of the present invention to provide a concrete exfoliation prevention construction method.

[0009]

To this end, in the concrete exfoliation prevention method according to claim 1 of the present invention, a step of performing a cross-section treatment of concrete, a step of performing a surface treatment of the foundation of concrete, and applying a primer to concrete. The step of applying the first intermediate coating to the concrete surface, the step of arranging the reinforcing material on the concrete surface, the step of applying the second intermediate coating to the concrete surface, and the step of applying the finish coating to the concrete surface. In a method for preventing concrete from coming off, a photosensitive resin is used as a part or all of the intermediate coating material and the finish coating material, and a flame retardant is filled in the primer and the photosensitive resin, and the photosensitive resin is cured by light irradiation. The invention according to claim 2 is characterized in that in claim 1, As the reinforcing material, a woven or knitted fabric, a mesh material, or a three-dimensional knitted material is used, and the invention according to claim 3 is the aramid fiber, the carbon fiber, or the reinforcing material according to claim 2. Woven or knitted fabric made of high strength polyethylene resin fiber,
A mesh product or a three-dimensional knitted fabric is used, and the invention according to claim 4 is characterized in that, in claim 3, the reinforcing material is coated with a paint having the same color as the concrete surface. The invention according to claim 2
Phenol FRP is used as the reinforcing material, and the invention according to claim 6 is the photosensitive resin holding sheet impregnated with a photosensitive resin in the step of the intermediate coating and the finishing coating according to claim 1. The invention according to claim 7 is characterized in that the film for preventing volatilization of a material such as styrene contained in the resin is arranged on both surfaces of the photosensitive resin holding sheet, A colored transparent light-shielding film for securing and adjusting a pot life is arranged on one side, and the invention according to claim 8 is the invention of claim 7, wherein the colored transparent light-shielding film side is prevented from volatilizing. 10. A film having an antifouling function is used as a film for a film,
The invention described in Claim 8 is characterized in that, as the film for preventing volatilization on the side of the colored transparent light-shielding film, a film heat-sealed to a substrate such as an organic fiber non-woven fabric is used. The invention according to claim 10 is the method according to claim 1, wherein some of the first intermediate coating step, the step of arranging the reinforcing material, the second intermediate coating and the step of the final coating, or the steps for the entire work. 12. A photosensitive resin holding sheet impregnated with a photosensitive resin and further provided with a reinforcing material, and the photosensitive resin holding sheet is attached to perform a curing operation by light irradiation. Is characterized in that a reinforcing material is disposed inside, on the upper surface or on the lower surface of the photosensitive resin holding sheet according to claim 10, and the invention according to claim 12 is the invention according to any one of claims 6 to 11. In the above, the invention is characterized in that after the holes for the air vent and the outlet are formed in the photosensitive resin holding sheet, the filler is inserted under pressure from the inlet. In 10,
An anchor is cast on concrete, a non-combustible material is lined on the surface of the photosensitive resin holding sheet to provide a fire resistant layer, and the invention according to claim 14 is characterized in that:
The anchor is supported by the reinforcing material, the non-combustible material is lined on the surface of the photosensitive resin holding sheet, and a fireproof layer is provided,
According to a fifteenth aspect of the present invention, a step of performing a cross-section treatment of concrete, a step of performing a surface treatment of the base of concrete, a step of applying a primer to concrete, a step of performing a first intermediate coating on the concrete surface, and a concrete step Placing a stiffener on the surface,
A second step of intermediate coating on the concrete surface,
In a concrete exfoliation prevention method comprising a step of applying a finish coating to a concrete surface, a photosensitive resin is used for a part or all of the intermediate coating material and the finish coating material, and a flame retardant or phenol FRP is used only for the finish coating. 16. The method according to claim 16, wherein
The invention described in any one of claims 1 to 15 is characterized in that the flame retardant or the fireproof layer is applied only to a specific portion.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a flow chart for explaining an example of the concrete exfoliation prevention method according to the present invention.

In FIG. 2, steps of steps S11 to S13 are the same as those of the conventional method described above. That is, in the pretreatment 1 of step S11, if the concrete has a float,
If there are missing parts, exposed or rusted reinforcing bars, or if there are cracks, perform cross-section processing by the appropriate method. Next, in the pretreatment 2 of step S12, a ground surface treatment is performed by sanding or high-pressure washing (for example, 15 MPa), and a primer is applied to the concrete surface in step S13. Resin such as unsaturated polyester or epoxy is used as the primer.

In the present invention, in order to shorten the working time after step S4 in FIG. 1, the following construction method is adopted. (Example of construction method 1) In step S14, the first intermediate coating is performed, in step S16, a reinforcing material such as a woven fabric, a knitted material, a mesh material, or a three-dimensional knitted material is attached and fixed, and in step S17, the second intermediate coating is performed. In step S19, finish coating is performed, but part or all of the intermediate coating and finish coating materials in steps S14, S17, and S19 are changed to photosensitive resin materials, and a series of work is applied work and curing work by light irradiation. Change to.

The photosensitive resin is a general term for photocurable resins which start to cure in response to irradiation with light rays in the wavelength range (1200 nm or less) including ultraviolet rays, visible rays, near infrared rays, etc. Photolysis insolubilization type, photolysis solubilization type,
It is classified into a light duplex type and a photopolymerization type. In relation to paints, photopolymerization type photosensitive resins are generally often used. Further, the photopolymerization type photosensitive resin includes radical polymerization type, radical addition type, cationic polymerization type, and the like, and unsaturated polyester type and acrylated epoxy resin are included in the radical polymerization type.

On the other hand, as the light source, in addition to ultraviolet rays, visible rays and near infrared rays (used wavelength range 380 to 1200 nm) are used. Here, as the light source, in addition to sunlight and natural light, any light source that emits visible light such as a metal halide lamp for illumination, a mercury lamp, or a fluorescent lamp can be used. The pot life (the time it takes for the photosensitive resin to come out of the bag completely shielded from light) to be effective is adjusted depending on the type and brightness of the light source. Illuminance 500 μw / cm ^{2 to} 1.5 at 380 to 450 nm
mw / cm ² ) within 10 minutes, or 3 in a bright room (illuminance of about 50 μw / cm ² in the wavelength range of 380 to 450 nm)
Since it is within the time, the curing and curing period can be significantly shortened as compared with the conventional method. (Construction method example 2) In the method of construction method example 1, it is premised that a woven fabric, a knitted fabric, a mesh product, a three-dimensional knitted fabric, or the like is used as the reinforcing material in step S16. Coarse woven or knitted fabrics, mesh or three-dimensional knitted fabrics are used in order not to cause poor curing. Here, the basis weight of the coarse woven fabric or knitted fabric, mesh product, or three-dimensional knitted fabric is set to about 300 g / m ^{2 or} less. Further, as the fibers used, glass fibers, vinylon fibers, etc. are used. (Construction Method Example 3) In Construction Method Example 2, a woven or knitted material, a mesh material, or a three-dimensional knitted material made of aramid fibers is used to further increase the light transmittance. Here, the basis weight of the woven or knitted fabric, mesh, or three-dimensional knitted fabric made of aramid fibers is set to about 180 g / m ^{2 or} less. Aramid fiber is an aggregate (bundle) with a single fiber diameter of about 12μ, and has a high specific strength (tensile strength 3.4 GPa,
350 kg / m ² ), the elongation at break is relatively large (elongation at break is about 4.6%). It is also possible to use carbon fibers. However, carbon fiber is not suitable for railways because it has conductivity. It is also possible to use high-strength polyethylene resin fibers which are high tensile strength fibers. However, the high linearity polyethylene resin fiber has a negative linear expansion coefficient,
That is, it has a peculiar property that it expands when the temperature drops, and it is necessary to pay attention to the operating temperature environment (the inside of the tunnel can be used because the temperature does not change significantly throughout the year).

By the way, the aramid fiber used in the present embodiment is generally very light brown, and the carbon fiber is generally black. On the other hand, the color of the photosensitive resin is almost colorless or slightly yellowish. Therefore, when considering attachment to a concrete surface, the area where the exfoliation prevention work is applied is different from the surrounding color. This color difference is particularly great when carbon fibers are used.

Therefore, by applying a color similar to that of the concrete portion on which the exfoliation preventive work is applied to the reinforcing material, the existence of the exfoliation preventive work is difficult to understand and the color difference is inconspicuous. Coloring may be performed by applying resin or paint. The color may be gray for ordinary concrete, and may be the color of the painted surface when the concrete surface is painted. According to this example, in the road tunnel, the driver is not visually burdened with extra load, and safe driving is not hindered. Also, by changing the ground color (black) to a white color like carbon fiber, the inside of the tunnel can be kept bright. In the case of aramid fiber, although the fiber has a characteristic that it is weak against ultraviolet rays, it has an effect that it also helps protect it. (Construction Method Example 4) FIG. 3 is a flow chart for explaining another example of the concrete exfoliation prevention construction method of the present invention. In addition,
In the following description, the description of the same steps as those in FIG. 2 will be omitted.

In FIG. 2, the photosensitive resin material is applied to a part or all of the intermediate coating material and the finish coating material, but in this example, steps S24, S27, S2.
All the operations of intermediate coating and finish coating in 9 have been changed to attaching a photosensitive resin holding sheet impregnated with a photosensitive resin and curing by light irradiation. Here, it is conceivable to use an organic fiber such as glass mat or polyester resin for the photosensitive resin holding sheet. Further, the photosensitive resin holding sheet may be used for any of the first and second intermediate coatings and finish coatings, or may be used for all three coatings. Further, when the adhesive force is insufficient when the photosensitive resin holding sheet is attached to the surface of the pre-work, the adhesive force may be supplemented.

For outdoor work, by placing a colored transparent light-shielding film on one side of the photosensitive resin holding sheet, the workable time (time until the photosensitive resin is taken out of the completely light-shielding bag and cured) ) Can be secured and adjusted, but the pot life under direct outdoor sunlight is as short as about 10 minutes (it can be extended to about 20 minutes by creating a shade). Furthermore, when the pot life is required, it is necessary to take measures to install a shield against sunlight or natural light, for example, a simple dark room at the attachment point.

FIG. 4 is a schematic sectional view showing a specific example of construction method example 4.

[0020]

[Embodiment 5] In this embodiment, as shown in FIG. 4A, a transparent film 3a1 for preventing volatilization of a material such as styrene contained in resin on both surfaces of the photosensitive resin holding sheet 3 of Embodiment 4. 3a2 (for example, a polyester film) is arranged, and a colored transparent light-shielding film 3b (for example, cellophane) for securing and adjusting the working life is arranged on one side. The role of the transparent films 3a1 and 3a2 is to prevent volatilization of styrene monomer, which is a reaction diluent in the resin during work and curing, and to prevent air obstruction on the surface of the sheet. The cured state of the part deteriorates).

The work procedure in this case will be described. First, take out the photosensitive resin holding sheet from the bag made of light-shielding material, peel off the transparent film 3a1 on the side to be attached to the concrete surface, carefully put the sheet on the concrete surface coated with the primer so that air does not enter,
Use a roller to squeeze the sheet and bring it into close contact with the concrete surface. At this time, a small amount of a putty material of a photosensitive resin may be applied for the purpose of improving the familiarity between the sheet and the primer. After that, the colored transparent light-shielding film 3b is taken, and light is applied to the sheet by illumination or natural light to cure the photosensitive resin. Finally, the transparent film 3a2 on the surface is peeled off.

Since three films are used in the above work, it is necessary to finally peel off the transparent film 3a2 arranged below the colored transparent light-shielding film 3b, and the amount of waste increases. The problem is that

Therefore, instead of the transparent film 3a1 on the front side of FIG. 4 (A), a transparent film 3c having an antifouling function is arranged as shown in FIG. 4 (B). This film 3c
As the material, a resin film having water repellency or hydrophilicity is used. Examples of the former include films of silicone resin, fluororesin, Teflon (registered trademark) resin, acrylic, urethane-based resin, and the like, and examples of the latter include films of polycarbonate resin and the like. Further, a film that adheres to the photosensitive resin as the photosensitive resin cures may be used, or a resin film that has a laminated structure and that is easily adhered to the photosensitive resin may be used.
According to this example, it is possible to eliminate the trouble of peeling the film, reduce the amount of dust, and impart a stainproof function to the surface of the sheet.

In the example of FIG. 4C, the transparent film 3 is used.
A material in which d is thermally fused to a substrate such as an organic fiber nonwoven fabric is used. For example, a method in which a urethane-based film is heat-sealed to a felt base material, and further to a base material such as an existing organic fiber nonwoven fabric is also considered. According to this example, the bonding with the photosensitive resin cured body can be made stronger. (Construction method example 5) FIG. 5 is a flow chart for explaining another example of the concrete falling-off prevention construction method of the present invention. In this example, in the factory, some of the first intermediate coating, the application of the reinforcing material, the second intermediate coating, and the continuous coating of the finishing coating, or all the work, were impregnated with a photosensitive resin. One sheet of photosensitive resin holding sheet, which is a combination of resin holding sheet and reinforcing material, is carried into the site, and in steps S34, S
At 35, only sticking work and curing work by light irradiation should be performed. If the adhesive force is insufficient when the photosensitive resin holding sheet is attached to the surface of the previous work, the adhesive force may be supplemented.

FIG. 6 is a schematic sectional view showing a specific example of the construction method example 5. In the figure, 1 is base concrete, 2 is a primer, 3 is a photosensitive resin holding sheet impregnated with a photosensitive resin, and 4 is a reinforcing material made of a mesh material. The figure (A) arranges the reinforcing material 4 inside the photosensitive resin holding sheet 3, the figure (B) arranges the reinforcing material 4 on the upper side of the photosensitive resin holding sheet, and the figure (C) shows the reinforcing material 4. An example in which the photosensitive resin holding sheet is arranged on the lower side is shown. By arranging the reinforcing material 4 on the lower side or the upper side of the photosensitive resin holding sheet 3, it is possible to reduce the time and effort for manufacturing the sheet. By separating the reinforcing material 4 from the photosensitive resin holding sheet 3, Workability can be improved. Furthermore, when the reinforcing material 4 is arranged on the lower side of the photosensitive resin holding sheet 3, the light shielding effect by the light irradiation of the photosensitive resin can be completely omitted.
In this arrangement, as long as the fixing performance with the primer 2 can be secured, the material of the mesh material and the roughness of the mesh do not have to be a problem.

Further, when a high-strength mesh material such as aramid fiber is used as a reinforcing material, the mesh wire material of the reinforcing material can be made thin and coarse, and the photosensitive resin has a light-transmitting property. The deformation can be easily observed even after reinforcement. (Construction method example 6) The photosensitive resin holding sheet impregnated with the photosensitive resin shown in construction method example 5 was manufactured by protruding a reinforcing material from the end portion of the sheet. It is used as a stacking margin for the photosensitive resin holding sheet to be pasted. In this case, it is possible to reduce weak portions in strength. Incidentally, when reinforcement is required for the discontinuous portion of the photosensitive resin holding sheet, a photosensitive resin holding sheet impregnated with a photosensitive resin is attached to the discontinuous portion, or a resin is filled in the gap, By curing
It should have continuity. Further, by using the sheet or the method of this example, even when the work for preventing the concrete from falling off and reinforcing it is carried out over a large area, it is possible to work at many points at the same time, which can further improve the workability. it can. (Construction Example 7) When the photosensitive resin holding sheet is attached, the working efficiency is improved in a normal portion, but there are facilities such as an opening, a step (uneven) and a ladder in the covered portion, When a fine feature is required, the method is changed to the application of the photosensitive resin material of Construction method example 1. According to this construction method, the sticking of the photosensitive resin holding sheet and the coating of the photosensitive resin material are used in combination, so that the work can be advanced without degrading the efficiency even in the work in detail. (Construction Example 8) The photosensitive resin holding sheet is carefully attached by an operator, and by applying a roller or the like, close contact and air defoaming are performed. However, there is a case where air is trapped on the back surface of the sheet due to a short working time or carelessness. In such a case, when it is determined that there is a functional problem in the found air pocket after the sheet is cured, the following measures are taken.

First, holes are formed in the sheet as an inlet and an outlet for venting air. Do not scratch the reinforcing material in this work (this work is easy because the photosensitive resin holding sheet is permeable). Next, a filler made of a resin having low viscosity is inserted by applying pressure from the inlet. At this time, a slight negative pressure may be applied to the outlet. The filling is completed when the filling material is filled in the air reservoir and the filling material overflows from the outlet. After that, it is sufficient to cure the filler. Further, if it is determined that there is a problem in strength just by inserting a filler due to a large air pocket, a photosensitive resin holding sheet may be laminated on the surface of the relevant portion to strengthen the strength. . According to this construction method, the filler can be injected into the air reservoir without damaging the reinforcing material by utilizing the property of the photosensitive resin holding sheet that is transparent.

Next, the features of the present invention will be described. In the concrete exfoliation prevention method according to the present invention described above, a primer or a photosensitive resin containing a resin component such as an unsaturated polyester or an epoxy resin, and further a resin woven or knitted material, a meshed material, or a three-dimensional knitted material or a photosensitive material. A resin holding sheet is used. After curing, these materials do not ignite with sparks such as welding, but since they are resin materials by nature, they are ignited and produce soot and burn if they are struck for several minutes by an open flame. (JISK720
The oxygen index according to 1 is 17.5 for unsaturated polyester.
% With epoxy resin and 19.8%. The oxygen index expresses the flammability of plastics, and the minimum oxygen required for the test piece to continue burning by igniting the top end of the test piece placed vertically in an oxygen / nitrogen mixed atmosphere with a flame of LP gas. It shows the concentration. ) Therefore, when the fire resistance performance is required in the object to which the concrete exfoliation prevention method is applied, improvement of the fire resistance performance is required. Therefore, an embodiment of the present invention for improving the fire resistance will be described below.

[0029]

[Embodiment 1] In this embodiment, a flame-retardant agent is used in order to improve the fire resistance of resin in a photosensitive resin holding sheet of primer application, first intermediate coating, second intermediate coating, and final coating. Fill. Examples of flame retardants include halogen-based, phosphorus-based, metal compound-based (aluminum hydroxide), inorganic-based materials (silica, ceramic powder), and the like.

[0030]

Second Embodiment In this embodiment, phenol FRP is used as a reinforcing material. As a result, the oxygen index of the reinforcing material can be greatly improved to 56%.

[0031]

[Embodiment 3] In this embodiment, the flame retardant of Embodiment 1 or the phenol FRP of Embodiment 2 is used only for finish coating. Here, when the light transmittance is insufficient, the finishing layer is naturally dried. According to this embodiment, the finish layer can be made flame-retardant regardless of the light transmittance without affecting the curing operation of the photosensitive resin.

[0032]

[Embodiment 4] In this embodiment, as shown in FIG. 7, an anchor 6 is placed on a base concrete 1 and a non-combustible material such as ceramics (alumina-silica foam material) or wool (glass wool, rock wool) is used. A refractory layer 5 is provided by covering the surface of the photosensitive resin holding sheet 3. Thereby, the refractory layer 5 can be installed easily and firmly. Also,
Since the photosensitive resin transmits light, the anchor 6 can be placed on the concrete surface without damaging the net of the reinforcing member 4.

[0033]

Fifth Embodiment This embodiment is different from the fourth embodiment in that a support plate 6a is provided at the tip of an anchor 6 and the support plate 6a is supported by a reinforcing member 4 as shown in FIG. . According to the present embodiment, it is possible to save the labor and time for placing the anchor on the concrete surface, and to adversely affect the concrete skeleton by placing the anchor on the concrete surface (cross-section loss due to drilling, drilling It is possible to prevent cracks due to impact or anchor fixing, and generation of water supply due to incomplete resin filling.

[0034]

Sixth Embodiment In this embodiment, as shown in FIG. 9, the refractory layer 5 of the first to fifth embodiments is applied only to a specific portion L of the tunnel 7. As a result, it is possible to reliably prevent the spread of fire. Also, the advantage of using a photosensitive resin that the concrete surface can be observed even after repairing,
No extra effort or expense.

[0035]

As is apparent from the above description, according to the present invention, the working time can be significantly reduced and the fire resistance can be improved by shortening the curing time and curing period of the resin material. As a result, the following effects are exhibited. (1) During construction related to transportation facilities, the time for traffic interruptions can be greatly reduced, and the burden on users and the impact on road congestion can be suppressed. (2) In the construction related to railway facilities, the work can be efficiently carried out within a short time during the night when there is no train operation. (3) Since work efficiency can be improved, it is possible to construct a large area within a given time. (4) The tool required for curing is only the light source, and it is possible to perform work simultaneously in many places of the enforcement section, which can further improve work efficiency. (5) When the photosensitive resin holding sheet is used, the thickness and the like can be easily controlled, the control of the state of the coating film can be omitted, and the quality can be improved. (6) When the photosensitive resin holding sheet is used, materials such as resin do not scatter around and the surrounding equipment and facilities are not polluted.

[Brief description of drawings]

FIG. 1 is a flow chart for explaining an example of a conventional concrete exfoliation prevention construction method.

FIG. 2 is a flow chart for explaining an example of a concrete exfoliation prevention method according to the present invention.

FIG. 3 is a flow chart for explaining another example of the concrete exfoliation prevention construction method according to the present invention.

FIG. 4 is a schematic cross-sectional view showing a specific example of construction method example 4.

FIG. 5 is a flow chart for explaining another example of the concrete exfoliation prevention construction method according to the present invention.

FIG. 6 is a schematic cross-sectional view showing a specific example of construction method example 5.

FIG. 7 is a sectional view showing an embodiment of the present invention.

FIG. 8 is a sectional view showing another embodiment of the present invention.

FIG. 9 is a perspective view showing another embodiment of the present invention.

[Explanation of symbols]

1 ... Base concrete 2 ... primer 3 ... Photosensitive resin holding sheet 4 ... Reinforcement material

Claims (16)

[Claims] Claim: What is claimed is: 1. A step of treating a section of concrete, a step of treating a surface of an underlayer of concrete, a step of applying a primer to concrete, a step of applying a first intermediate coating on the concrete surface, and a step of reinforcing the concrete surface. In a method for preventing concrete from falling off, which comprises a step of arranging materials, a step of applying a second intermediate coating on the concrete surface, and a step of applying a final coating on the concrete surface, part or all of the intermediate coating material and the finishing coating material. In addition to using a photosensitive resin, the primer and photosensitive resin are filled with a flame retardant,
A concrete exfoliation prevention method characterized by curing a photosensitive resin by light irradiation. 2. The concrete exfoliation prevention method according to claim 1, wherein a woven or knitted fabric, a mesh product, or a three-dimensional knitted fabric is used as the reinforcing material. 3. The concrete according to claim 2, wherein a woven or knitted material, a meshed material or a three-dimensional knitted material made of aramid fiber, carbon fiber or high strength polyethylene resin fiber is used as the reinforcing material. Construction method. 4. The method for preventing concrete from falling off according to claim 3, wherein the reinforcing material is coated with a paint having the same color as the surface of the concrete. 5. The concrete exfoliation prevention method according to claim 2, wherein phenol FRP is used as the reinforcing material. 6. The concrete exfoliation prevention method according to claim 1, wherein a photosensitive resin holding sheet impregnated with a photosensitive resin is attached in the steps of the intermediate coating and the final coating. 7. A film for preventing volatilization of a material such as styrene contained in the resin is arranged on both sides of the photosensitive resin holding sheet, and one side is provided with a colored transparent light-shielding film for securing a pot life and adjusting the same. 7. A method for preventing concrete from falling off according to claim 6, further comprising disposing a film for the concrete. 8. The method for preventing concrete from falling off according to claim 7, wherein a film having an antifouling function is used as a volatilization-preventing film on the colored transparent light-shielding film side. 9. The concrete according to claim 8, wherein the film for volatilization prevention on the side of the colored transparent light-shielding film is a film heat-sealed to a substrate such as an organic fiber nonwoven fabric. Stripping prevention method. 10. A photosensitive resin is applied to several consecutive steps of the first intermediate coating step, reinforcing material placement step, second intermediate coating step and final coating step 2. The method for preventing concrete from falling off according to claim 1, wherein a photosensitive resin holding sheet impregnated with a reinforcing material is provided, and the photosensitive resin holding sheet is attached to perform a curing operation by light irradiation. 11. The concrete exfoliation prevention method according to claim 10, wherein a reinforcing material is arranged inside, on the upper surface or on the lower surface of the photosensitive resin holding sheet. 12. The method according to claim 6, wherein holes are formed in the photosensitive resin holding sheet to serve as inlets and outlets for air venting, and then the filler is inserted under pressure from the inlets. Concrete peeling prevention method described in. 13. The concrete exfoliation prevention method according to claim 10, wherein an anchor is cast on the concrete, and a non-combustible material is lined on the surface of the photosensitive resin holding sheet to provide a fireproof layer. 14. The concrete exfoliation prevention method according to claim 10, wherein an anchor is supported by the reinforcing material, and a non-combustible material is lined on the surface of the photosensitive resin holding sheet to provide a fireproof layer. 15. A step of treating a section of concrete, a step of treating a surface of an underlayer of concrete, a step of applying a primer to concrete, a step of applying a first intermediate coating to the concrete surface, and a step of reinforcing the concrete surface. In a method for preventing concrete from falling off, which comprises a step of arranging materials, a step of applying a second intermediate coating on the concrete surface, and a step of applying a final coating on the concrete surface, part or all of the intermediate coating material and the finishing coating material. A photosensitive resin is used for the flame retardant or phenol F only for the finish coating.
Concrete peeling prevention method characterized by using RP. 16. The concrete exfoliation prevention method according to claim 1, wherein the flame retardant or the fire resistant layer is applied only to a specific portion.