JP2007040026A - Repair panel and repair construction method of concrete structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a repair panel for a concrete structure capable of being simply and inexpensively constructed and reused in the other repair section after construction and to provide a repair construction method for the concrete structure. <P>SOLUTION: This repair panel 10 is provided with a hollow fiber sheet 16 having a continuous space 28 in the inside, a surface layer 18 and a rear surface layer 20 formed by impregnating resin into a surface and a rear surface of the hollow fiber sheet 16, and a spacer 24 attached to a peripheral fringe part of the rear surface layer 20 and ensuring a filling space 36 between the rear surface layer 20 and the concrete structure 12. A supply port 38 is formed in the surface layer 18, and a press-in port 40 is formed in the rear surface layer 20. In this repair construction method by use of the repair panel 10, chemical liquid is filled into the continuous space 28 and the filling space 36 by supplying the chemical liquid for achieving chemical rust prevention action from the supply port 38 into the continuous space 28 under a predetermined pressure, and the chemical liquid is poured into a crack 14 under the filling pressure. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a repair panel for a concrete structure and a repair method using the same for injecting a chemical solution that exerts a chemical rust prevention action on cracks generated in the concrete structure.

  Air-borne concrete structures such as revetments, waterways, piers, or building houses deteriorate over time due to salt damage, alkali aggregate reaction, frost damage, etc., but the deterioration progresses and cracks occur in the concrete structure. Then, when a large amount of moisture and oxygen is supplied from there, the internal rebar is corroded. Therefore, conventionally, repair of a concrete structure whose main purpose is rust prevention of reinforcing bars has been performed by a repair method as shown in FIG. 7 or FIG.

In the repair method shown in FIG. 7, the injector 3 is installed at predetermined intervals of 30 to 50 cm in the crack 2 in the concrete structure 1, the sealing 4 is applied to the crack 2, and then the chemical solution is injected into the crack 2. It is what I did. On the other hand, in the repair method shown in FIG. 8, the three-dimensional glass fiber fabric 5 and the cover 6 can be bonded to the repair target surface of the concrete structure 1 at the site and solidified in the hollow portion of the three-dimensional glass fiber fabric 5. By supplying a chemical solution (epoxy resin or the like) from the injector 3, the chemical solution is injected from the entire surface of the three-dimensional glass fiber fabric 5 into the crack 2 (see Patent Document 1).
JP-A-8-184194

  In the conventional repair method shown in FIG. 7, since the chemical solution is injected at two points in the two-dimensional crack 2, the concentration of the chemical solution in the reinforcing bar 7 tends to be uneven, In the case of using a chemical solution having a chemical rust preventive action such as a lithium nitrate solution, the difference in concentration caused a new macrocell corrosion. In addition, since it is difficult to completely inject the chemical solution into the fine crack 2, there is a risk that an appropriate treatment cannot be performed even though it is a corroded portion. Further, since the sealing 4 is applied to the crack 2, there is a problem that the construction cost becomes high.

  On the other hand, in the conventional repair method shown in FIG. 8, since the chemical solution is injected into the crack 2 at the “surface”, the chemical solution can be injected into the fine crack 2 without any leakage. However, since the three-dimensional glass fiber fabric 5 and the cover 6 are bonded to the concrete structure 1 on site, there is a problem that the construction is troublesome and the removal after the construction is difficult. Moreover, since the solidifiable chemical solution was used, after the construction, the solidified chemical solution remains in the hollow portion of the three-dimensional glass fiber fabric 5, even if the three-dimensional glass fiber fabric 5 is removed, It could not be diverted to repair locations.

  Therefore, the main problem of the present invention is that a repair panel and a repair method for a concrete structure can be injected without any chemicals even for fine cracks, can be easily and inexpensively constructed, and can be diverted to other repair locations after construction. Is to provide.

  The invention described in claim 1 is a repair panel 10 for a concrete structure for injecting a chemical solution having a chemical rust prevention action into a crack 14 generated in the concrete structure 12, and a continuous space 28 through which the chemical solution passes. Are attached to the peripheral portion of the back layer 20 and the back layer 20 formed by impregnating the surface A and back B of the hollow fiber sheet 16 with resin. A spacer 24 is provided between the layer 20 and the concrete structure 12 to secure a filling space 36 for filling the chemical solution, and a supply port 38 for supplying the chemical solution to the continuous space 28 is formed in the surface layer 18. In addition, the back layer 20 is a repair panel 10 "for a concrete structure in which a pressure inlet 40 for pressing a chemical solution from the continuous space 28 into the filling space 36 is formed. .

  In this invention, since it has the hollow sandwich structure which pinched | interposed the hollow fiber sheet 16 with the surface layer 18 and the back layer 20, it is lightweight and highly rigid compared with a normal FRP board. Moreover, since the hollow fiber sheet 16, the surface layer 18, and the back surface layer 20 are integrated, it is not necessary to bond these on site. Furthermore, since it is used for the injection | pouring of the chemical | medical solution which has a chemical rust prevention effect | action, the use of the chemical | medical solution which does not have a solidification property is possible, and the diversion after construction is possible.

  The invention described in claim 2 is characterized in that, in the invention described in claim 1, "the reinforcing layer 22 is laminated on the surface layer 18".

  In the repair panel 10 for a concrete structure according to the first aspect of the present invention, the surface layer 18 is reinforced by the reinforcing layer 22.

  The invention described in claim 3 is “the hollow fiber sheet 16 having the continuous space 28 therein, and the surface layer 18 and the back layer formed by impregnating the surface A and the back B of the hollow fiber sheet 16 with resin. 20 and a spacer 24 which is attached to the peripheral portion of the back layer 20 and secures a filling space 36 between the back layer 20 and the concrete structure 12, and the surface layer 18 has a supply port 38. Is formed, and the back surface layer 20 is a repair method using the repair panel 10 of the concrete structure in which the pressure inlet 40 is formed, and (a) the spacer 24 is provided on the surface of the concrete structure 12. In the state of contact, the repair panel 10 is installed so as to cover the crack 14 generated in the concrete structure 12, and (b) the supply port 38 By supplying a chemical solution having a chemical rust preventive action to the connecting space 28 at a predetermined pressure, the chemical solution is filled into the continuous space 28 and the filling space 36, and the chemical solution is applied to the crack 14 by the filling pressure. And (c) a repair method for a concrete structure in which the repair panel 10 is removed from the concrete structure 12.

  In the present invention, since a chemical solution having a chemical rust preventive action is used, it is possible to use a chemical solution that does not have a solidifying property, and it is possible to prevent the chemical solution from remaining in the continuous space after construction.

  According to the first and second aspects of the invention, since the hollow sandwich structure is employed, it can be formed with light weight and high rigidity, so that workability and durability can be improved. Moreover, since it is not necessary to adhere | attach a hollow fiber sheet, a surface layer, and a back layer on-site, it can construct easily and cheaply. In addition, since the chemical solution can be injected on the “surface” against the crack, the chemical solution can be injected even if it is a fine crack.

  According to the invention described in claim 3, since the chemical solution exhibiting the chemical rust prevention action is used, it is possible to prevent the chemical solution from remaining in the continuous space after the construction. Therefore, after removing the repair panel from the concrete structure, it can be diverted to another repair location. In addition, since it is possible to inject chemicals at the “surface” under a predetermined pressure against cracks, it is possible to inject all chemicals even for fine cracks, and to make the concentration of chemicals in the rebar uniform. Can do.

  FIG. 1 is a cross-sectional view (a cross-sectional view taken along the line II in FIG. 1) showing a repair panel 10 of a concrete structure to which the present invention is applied, and FIG. 2 is a bottom view showing the repair panel 10.

  As shown in FIG. 6, the repair panel 10 (FIG. 1, FIG. 2) is a “surface” that has a chemical solution such as a lithium nitrite solution on the cracks 14 generated in the concrete structure 12. By injecting, the reinforcing bar 12a is prevented from corroding and includes a hollow fiber sheet 16, a surface layer 18, a back layer 20, a reinforcing layer 22, a spacer 24, and a sealing material 26.

  The hollow fiber sheet 16 is a three-dimensional woven fabric made of glass fibers, and is configured by weaving X-direction fibers 16a, Y-direction fibers 16b, and Z-direction fibers 16c as shown in FIG. Moreover, the peripheral part of the hollow fiber sheet 16 is crushed with a crimping jig or the like as a water stop treatment for preventing leakage of the chemical liquid (FIG. 1).

  And as shown in FIG. 4, the surface layer 18 is formed by impregnating the surface A which consists of fibers 16a-16c with resin, such as polyester, and the same resin is applied to the back surface B which consists of fibers 16a-16c. The back layer 20 is formed by impregnation. Moreover, the continuous space layer 30 which has the continuous space 28 is formed by impregnating the resin to the support | pillar C which consists of the fiber 16c, and the water stop part 32 is impregnated by impregnating the resin to the peripheral part of the hollow fiber sheet 16. (FIG. 1) is formed.

  Thus, the hollow fiber sheet 16 and the surface layer 18 and the back layer 20 are integrated through the resin, and the strength of the repair panel 10 is ensured by the hollow sandwich structure of the integrated body 34. Lighter weight has been achieved.

  Note that if the amount of resin impregnated in the hollow fiber sheet 16 is small, the rigidity of the repair panel 10 is small, and if it is large, the capacity of the continuous space 28 cannot be sufficiently secured. Therefore, in this embodiment, considering the balance between the rigidity of the repair panel 10 and the capacity of the continuous space 28, 390 g of resin (polyester) with respect to the hollow fiber sheet 16 having a size of 50 cm × 50 cm and a thickness of 3 mm. Is impregnated.

  The reinforcing layer 22 (FIG. 1) reinforces the surface layer 18, and, as shown in FIG. 5, a cover sheet 22a made of a polyester nonwoven fabric or glass mat is bonded to the surface layer 18 in the integrated object 34. Are stacked on the surface of the surface layer 18.

  In this embodiment, the reinforcing layer 22 is laminated only on the surface layer 18, but the reinforcing layer 22 may be laminated on both the surface layer 18 and the back layer 20. Further, when sufficient strength can be obtained by the surface layer 18 or the back layer 20, the reinforcing layer 22 may not be laminated. Further, in this embodiment, the reinforcing layer 22 is formed by adhering the cover sheet 22a to the surface layer 18, but the cover sheet 22a is placed on the surface A (FIG. 3) of the hollow fiber sheet 16, The surface layer 18 and the reinforcing layer 22 may be simultaneously formed by impregnating them with a resin.

  The spacer 24 secures a filling space 36 (FIG. 6) for filling the chemical solution between the back layer 20 and the concrete structure 12, and prevents deformation and dropping of the sealing material 26, and is a resin such as polyester. Is formed in a band shape (for example, a width of 2 to 3 cm and a thickness of 2 mm). The spacer 24 is attached to the peripheral edge of the back layer 20 by adhesion or the like.

  The sealing material 26 prevents leakage of the chemical liquid filled in the filling space 36, and is formed in a band shape (for example, 5 cm wide × 5 mm thick) by an elastic material such as soft rubber. The sealing material 26 is annularly arranged inside the spacer 24.

  In this embodiment, both the spacer 24 and the sealing material 26 are used. However, if the spacer 24 has a sealing function, the sealing material 26 is unnecessary.

  The surface layer 18 is formed with at least one supply port 38 for supplying the chemical liquid to the continuous space 28, and the back surface layer 20 has a plurality of pressure inlets for pressing the chemical liquid from the continuous space 28 into the filling space 36. 40 is formed.

  The size and position of the supply port 38 are not particularly limited, but according to experiments, when the overall size is about 50 cm × 50 cm, the supply port 38 having a diameter of about 10 mm is formed at the center of the surface layer 18. It has been confirmed that the desired effect can be obtained when only one is formed.

  The size and the formation position of the pressure inlet 40 are not particularly limited. However, in order to prevent the bending strength from being lowered and to make the filling pressure in the filling space 36 uniform, the pressure inlet 40 is formed on the entire surface of the back layer 20. It is desirable that relatively small pressure inlets 40 are formed at equal intervals. According to experiments, it has been confirmed that good results can be obtained in both strength and filling pressure when the pressure inlets 40 having a diameter of about 2 mm are formed at intervals of about 5 cm.

  In the repair panel 10, the thicker the thickness, the greater the shear deformation between the layers in the hollow sandwich structure, and the lower the bending rigidity at the initial stage of loading. Further, as the thickness increases, the amount of the chemical stored in the continuous space 28 increases, which is uneconomical. Therefore, in this embodiment, the repair panel 10 is configured using the thinnest 3 mm of standard specifications of the commercially available hollow fiber sheet 16.

  In the repair panel 10, the larger the size, the less the number of sheets used, but the worse the workability of construction and the convenience of transportation. Moreover, it becomes difficult to apply to various shapes of the concrete structure 12. Therefore, in this embodiment, the repair panel 10 is configured using a 50 cm × 50 cm hollow fiber sheet 16 in consideration of workability of construction and convenience of transportation.

  When repairing the concrete structure 12 in which the crack 14 has been generated using the repair panel 10, first, as shown in FIG. 6, the crack 14 is made with the spacer 24 in contact with the surface of the concrete structure 12. The repair panel 10 is installed so as to cover.

  That is, in a state where the repair panel 10 is arranged at the repair location, the water stop portions 32 on the four sides of the repair panel 10 are pressed by the rod-shaped fixing members 42, and the fixing members 42 are pressed by the bolts and nuts 44 to the concrete structure 12. To fix. In addition, a pressure hose 48 is connected to the supply port 38 via a mounting jig 46, and this pressure hose 48 is connected to a high-pressure cylinder (not shown) such as liquid nitrogen that pumps the chemical solution.

  As the fixing member 42, it is desirable to use a lightweight and highly rigid material such as an aluminum box channel of about 50 mm × 50 mm. In addition, it is desirable to simultaneously fix a plurality of repair panels 10 using a long fixing member 42 in order to increase construction efficiency, and it is desirable to use a mounting jig 46 having a check function.

  When the installation of the repair panel 10 is completed, the chemical liquid fed from the high pressure cylinder is supplied from the supply port 38 to the continuous space 28 at a predetermined pressure, and the continuous space 28 and the filling space 36 are filled with the chemical liquid, and the filling pressure To inject the chemical into the crack 14.

  As a method for pressurizing the chemical solution, in addition to pressurization by a high-pressure cylinder, pressurization by a compressor or the like is conceivable, but static pressurization is possible in that a temporary facility such as a power source is not required. In this respect, pressurization with a high-pressure cylinder is desirable. Since the limit load pressure at which the bending failure of the repair panel 10 occurs is about 200 kPa, the filling pressure of the chemical solution is preferably 100 kPa or less in view of safety.

  When the injection of the chemical solution is completed, the repair panel 10 is removed from the concrete structure 12, and this is diverted to other repair locations as necessary.

The inventors verified the rust prevention effect by the repair method using the repair panel 10 of the present example by the following experiment.
[Experiment]
Experimental method: A concrete structure having a cover thickness of 70 mm, an interval between reinforcing bars (diameter: 16 mm) of 250 mm, and a size of 50 cm × 50 cm × 20 cm is produced. Cracks were forcibly introduced. And the repair panel 10 of a present Example was installed in the repair location of this concrete structure (specimen), and the above-mentioned repair construction method was implemented as "Example." For the same specimen, the conventional repair method shown in FIG. 7 was executed as a “comparative example”. The specific conditions of “Example” and “Comparative Example” are as shown in [Table 1] and [Table 2] below.

And when construction of "Example" and "Comparative Example" was completed, samples were taken at respective crack positions, and the concentration of nitrite ions contained in concrete having a depth of 60 to 70 mm from the surface was analyzed.
Experimental results: The experimental results are as shown in [Table 3].

  From [Table 3], it can be seen that the nitrite ion concentration of the “Example” is significantly higher than the nitrite ion concentration of the “Comparative Example”, and an effective rust prevention treatment can be performed.

In addition, it is said that the rust prevention effect of nitrite ion in salt damage deterioration is required to be 1 or more in terms of molar ratio with chlorine ion, and when the chlorine ion concentration in concrete is assumed to be 4.8 kg / m ³ Therefore, the necessary nitrite ion concentration is 2,708 mg / kg. Looking at "Example" and "Comparative Example", the average value of nitrite ion concentration is both above the required nitrite ion concentration, but in some of the "Comparative Examples" it does not exceed this, It can be said that corrosion due to salt damage may recur.

Cross section showing repair panel for concrete structure Bottom view showing repair panel for concrete structure Perspective view showing a hollow fiber sheet The perspective view which shows the integrated object which integrated the hollow fiber sheet, the surface layer, and the back layer. The perspective view which shows the method of laminating a reinforcement layer on a surface layer Sectional view showing repair method for concrete structure Perspective view showing conventional repair method (point injection) Perspective view showing conventional repair method (surface injection)

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Repair panel 12 ... Concrete structure 12a ... Reinforcing bar 14 ... Crack 16 ... Hollow fiber sheet 18 ... Surface layer 20 ... Back layer 22 ... Reinforcement layer 22a ... Cover sheet 24 ... Spacer 26 ... Sealing material 28 ... Continuous space 30 ... Continuous Space layer 32 ... Water stop 36 ... Filling space 38 ... Supply port 40 ... Pressure inlet 42 ... Fixing member

Claims (3)

It is a repair panel for a concrete structure for injecting a chemical solution that exerts a chemical rust prevention action on cracks generated in the concrete structure,
A hollow fiber sheet having a continuous space through which the chemical solution passes, a surface layer and a back layer formed by impregnating a resin on the front and back surfaces of the hollow fiber sheet, and attached to a peripheral portion of the back layer, A spacer for ensuring a filling space for filling the chemical solution between the back layer and the concrete structure;
In the surface layer, a supply port for supplying the chemical liquid to the continuous space is formed, and in the back layer, a pressure inlet for press-fitting the chemical liquid from the continuous space to the filling space is formed, Repair panel for concrete structures.   The repair panel for a concrete structure according to claim 1, wherein a reinforcing layer is laminated on the surface layer. A hollow fiber sheet having a continuous space through which a chemical solution having a chemical rust preventive action passes, a surface layer and a back layer formed by impregnating a resin on the surface and the back of the hollow fiber sheet, and the back layer A spacer that is attached to a peripheral portion and includes a spacer that secures a filling space for filling the chemical solution between the back layer and the concrete structure, and supplies the chemical solution to the continuous space on the surface layer A mouth is formed, and the back surface layer is a repair method using a repair panel of a concrete structure in which a pressure inlet for pressing the chemical liquid from the continuous space into the filling space is formed,
(A) In the state where the spacer is in contact with the surface of the concrete structure, the repair panel is installed so as to cover cracks generated in the concrete structure,
(B) By supplying the chemical solution from the supply port to the continuous space at a predetermined pressure, the chemical solution is filled into the continuous space and the filling space, and the chemical solution is injected into the crack by the filling pressure. ,
(C) A repair method for a concrete structure in which the repair panel is removed from the concrete structure.