JP2014070389A - Reinforcement structure of reinforced concrete structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and inexpensively achieve a reinforcement structure for imparting sufficient strength to an existing reinforced concrete structure.SOLUTION: A reinforcement structure includes: a slit 10 that is formed toward its outer surface side from its inner surface side in a reinforced concrete structure; a fiber-reinforced member 13 that is arranged in the slit 10; and a filler 14 that is infilled into the slit 10 with the arranged fiber-reinforced member 13. A plurality of through-holes are provided in the fiber-reinforced member 13.

Description

  The present invention relates to a reinforcing structure for a reinforced concrete structure, and more particularly to a shear reinforcing structure.

  In recent years, there is a strong concern about the occurrence of large-scale earthquakes, and the need for seismic reinforcement for existing reinforced concrete structures is increasing. However, it is not easy to reinforce existing reinforced concrete structures. In particular, in a reinforced concrete structure such as an underpass or a tunnel constructed by a box culvert buried in the ground, it is extremely difficult to reinforce from the outer surface side covered with natural ground, and the cost increases.

  Therefore, Patent Document 1 describes a reinforcing structure in which an iron plate is inserted into a slit formed on the inner surface of an outer wall of an existing box culvert and filled with a grout material.

JP 2003-3556 A

However, the reinforcing structure described in Patent Document 1 has the following problems. That is, since the mortar generally used as the grout material has a weak adhesion to the iron plate, it is difficult for the reinforcing body composed of the iron plate and the grout material to work together. In addition, in order to cut the existing lateral reinforcing bars, it was complicated to take measures such as welding the cut reinforcing bars via the accessory bars.
The objective of this invention is implement | achieving the reinforcement structure which provides sufficient intensity | strength to the existing reinforced concrete structure simply and at low cost.

  The reinforcing structure of a reinforced concrete structure according to the present invention includes a slit formed in the reinforced concrete structure from the inner surface side toward the outer surface side, a reinforcing member disposed in the slit, and the slit in which the reinforcing member is disposed. The reinforcing member is provided with a plurality of through holes.

  In the reinforcing structure of a reinforced concrete structure of the present invention, the reinforcing member is a fiber reinforcing member knitted in a lattice shape with high-strength fibers.

  In the reinforcing structure for a reinforced concrete structure according to the present invention, the reinforcing member is a steel plate.

  In the reinforcing structure for a reinforced concrete structure according to the present invention, the steel plate is arranged in a bracing manner in the slit.

  ADVANTAGE OF THE INVENTION According to this invention, the reinforcement structure which provides sufficient intensity | strength to the existing reinforced concrete structure is implement | achieved simply and at low cost.

It is a perspective view which shows the box culvert concerning Embodiment 1. FIG. It is sectional drawing of the box culvert cut | disconnected along the plane X shown by FIG. It is aa expanded sectional view of FIG. It is an expanded sectional view which shows a part of construction process of the reinforcement structure shown by FIG. It is a perspective view of a fiber reinforcement member. It is an expanded sectional view which shows the modification of a reinforcement structure. It is an expanded sectional view showing other modifications of a reinforcement structure.

(Embodiment 1)
An example of an embodiment of a reinforcing structure for a reinforced concrete structure of the present invention (hereinafter abbreviated as “reinforcing structure”) will be described in detail with reference to the drawings. Here, the reinforcement structure provided in the side wall of the existing box culvert embed | buried underground is demonstrated.

  FIG. 1 shows two box culverts 1a and 1b having the reinforcing structure of the present invention. Each box culvert 1a, 1b has a pair of opposing side walls W1, W2, a top plate T, and a bottom plate B, and has a substantially rectangular tube-like appearance as a whole. Inside the side walls W1, W2, top plate T, and bottom plate B, main reinforcing bars and distribution reinforcing bars are arranged. Specifically, a plurality of main reinforcing bars are embedded in the side walls W1, W2, top plate T, and bottom plate B, and a plurality of distribution reinforcing bars are embedded so as to intersect the main reinforcing bars. In other words, the main reinforcing bars and the distribution reinforcing bars are embedded in a lattice pattern.

  Hereinafter, the reinforcing structure provided on the two side walls W1 and W2 of the box culverts 1a and 1b shown in FIG. 1 will be specifically described. However, the same reinforcing structure is provided on the two side walls W1, W2 of the box culverts 1a, 1b. Therefore, in order to avoid overlapping description, only the reinforcing structure provided on the side wall W1 of each box culvert 1a, 1b will be described, and description of the reinforcing structure provided on the side wall W2 will be omitted.

  FIG. 2 is a cross-sectional view of the box culverts 1a and 1b cut along the plane X shown in FIG. That is, FIG. 2 shows the inner surfaces of the side walls W1 of the box culverts 1a and 1b. Here, the outer surface of the box culverts 1a and 1b means a surface in contact with the natural ground, and the inner surface means a surface opposite to the outer surface.

  Reinforcing structures are provided at a plurality of locations on the side walls W1 of the box culverts 1a and 1b. In FIG. 2, the reinforcement location in each side wall W1 is typically shown with the broken line. That is, the side wall W1 of the box culvert 1a has two reinforcing portions (reinforcing portions 3a and 3b), and the side wall W1 of the box culvert 1b has three reinforcing portions (reinforcing portions 4a, 4b and 4c). But the reinforcement structure provided in each reinforcement location 3a, 3b, 4a, 4b, 4c is equipped with the same structure. Therefore, in order to avoid overlapping description, the reinforcing structure provided in the reinforcing part 3a will be described below, and the description of the reinforcing structure provided in the other reinforcing parts 3b, 4a, 4b, 4c will be omitted. To do.

  As shown in FIG. 3, a slit 10 is provided in the reinforcing portion 3a on the side wall W1 from the inner surface side toward the outer surface side. Furthermore, a fiber reinforcing member 13 as a reinforcing member is disposed inside the slit 10 and a filler 14 is filled therein.

  The reinforcing structure shown in FIG. 3 can be constructed as follows. As shown in FIG. 4A, the slit 10 is formed in the side wall W1 using an arbitrary method such as a concrete cutter or a water jet, or an arbitrary method such as the FON drill method (registered trademark). The height (H) of the illustrated slit 10 is 2 m, and the width (W) is 50 mm. In addition, although the number and the space | interval of the slit 10 can be set arbitrarily, it is preferable to form the slit 10 by 2-3 m space | interval.

  When the slit 10 is formed, a part of the reinforcing bars (main reinforcing bars and distribution reinforcing bars) embedded in the side wall W1 may be cut. However, when rebar is cut, sufficient safety and strength are preliminarily studied based on information such as ironing diagrams and non-destructive inspection results.

  Next, as shown in FIG. 4B, the fiber reinforcing member 13 is inserted into the slit 10 from the opening 10 a of the slit 10. Then, the filler 14 (FIG. 3) is filled into the slit 10 in which the fiber reinforcing member 13 is disposed. At this time, in order to hold the filler 14 inside the slit 10, a mold is installed as necessary. For example, the opening 10a of the slit 10 is closed with a plate material as a mold. The plate material is removed after the filler 14 is cured.

  As shown in FIG. 5, the fiber reinforcing member 13 is knitted (knitted) in a lattice shape with high-strength fibers (carbon fibers), and has stretchability, flexibility, and elasticity. . The high-strength fibers that form the fiber reinforcing member 13 are not limited to carbon fibers, and may be other high-strength fibers such as aramid fibers and glass fibers.

  Refer to FIG. 3 again. The outer dimension of the fiber reinforcing member 13 disposed inside the slit 10 is smaller than the inner dimension of the slit 10. That is, the fiber reinforcing member 13 has a dimension that can be completely accommodated in the slit 10. In the present embodiment, the length and width of the fiber reinforcing member 13 are each about 50 mm smaller than the height and depth of the slit 10. Moreover, the thickness of the fiber reinforcement member 13 is about 10 mm. Here, the thickness of the fiber reinforcing member 13 means the dimension of the slit 10 in the width direction.

  Cement-based mortar is used for the filler 14 filled in the slit 10. In the present embodiment, a mixture of a porazone substance such as cement, silica fume and quartz powder, a thickener and water is used as the filler 14. The filler 14 is filled around the fiber reinforcing member 13 and fills the inside of the slit 10 without a gap.

  Here, the adhesion force of the filler 14 to the fiber reinforcing member 13 is stronger than the adhesion force to the iron plate. For this reason, the fiber reinforcing member 13 and the filler 14 shown in FIG. 3 are firmly integrated. Furthermore, the fiber reinforcing member 13 in the present embodiment is knitted in a lattice shape. In other words, the fiber reinforcing member 13 is provided with a plurality of through holes penetrating the fiber reinforcing member 13 in the thickness direction. Therefore, the filler 14 filled in the slit 10 flows from the front side to the back side of the fiber reinforcing member 13 or from the back side to the front side through the through-holes opened in the fiber reinforcing member 13, and the inside of the slit 10 is a gap. Meet without. And after the filler 14 hardens | cures, the filler 14 entangles with the fiber reinforcement member 13, and both are integrated more firmly. The filler 14 is not limited to cement-based mortar, and for example, a resin-based material, fiber-mixed mortar, or the like can be used as the filler 14. But it is preferable that the filler 14 has the fluidity | liquidity which can be filled in the slit 10 without a clearance gap.

  The fiber reinforcing member 13 used in the reinforcing structure of the present embodiment has stretchability, flexibility, and elasticity, and can be easily cut with scissors, a cutter, or the like. Therefore, the operation | work which cut | disconnects the fiber reinforcement member 13 in the said dimension can be performed in a construction site for a short time, and a special tool and machine are not required for the operation | work. Of course, you may prepare the fiber reinforcement member 13 cut | disconnected by the said dimension previously.

  Moreover, since the fiber reinforcement member 13 knitted with high-strength fibers has higher strength than a steel reinforcement member or the like, a sufficient number of fiber reinforcement members 13 can provide sufficient reinforcement strength. Furthermore, sufficient reinforcing strength can be obtained even by the fiber reinforcing member 13 having a smaller thickness than a steel reinforcing member. For this reason, by using the fiber reinforcing member 13, the number of reinforcing members can be reduced or the thickness thereof can be reduced.

  Moreover, since the fiber reinforcement member 13 does not have a possibility of corrosion, high reinforcement strength is maintained over a long period of time. Furthermore, the fiber reinforcing member 13 that does not have the risk of corrosion can be installed in a portion where the cover concrete cannot be placed or where there is a lot of water leakage.

  In addition, the fiber reinforcing member 13 having stretchability, flexibility, and elasticity can also be disposed inside the slit 10 that is not linear. Further, the fiber reinforced member 13 that has elasticity, flexibility and elasticity and is lightweight is easy to handle even in a narrow construction site.

(Embodiment 2)
Hereinafter, a second embodiment of the reinforcing structure of the present invention will be described in detail with reference to the drawings. But the reinforcement structure which concerns on this embodiment has a basic structure in common with the reinforcement structure which concerns on 1st Embodiment. Therefore, only differences from the reinforcing structure according to the first embodiment will be described below, and descriptions of common structures will be omitted as appropriate. In addition, the same reference numerals are used for the same components as those already described, and a duplicate description is omitted.

  In the reinforcing structure according to the present embodiment, the opening 10 a of the slit 10 is closed by the plate material 15 as shown in FIG. The reinforcing structure shown in FIG. 6A is constructed as follows. As shown in FIG. 6B, the fiber reinforcing member 13 having the end plate 15 integrally provided with the end face is inserted into the slit 10 from the opening 10a. Next, the plate 15 is held in a slightly inclined state, a gap is formed between the back surface 15a of the plate 10 and the opening 10a of the slit 10, and the filler 14 is filled into the slit 10 through the gap. . When a sufficient amount of filler 14 is filled, the plate 15 is made vertical and the opening 10a is closed by the plate 15. As described above, the plate material 15 functions as a mold when filling the filler 14, and functions as a lid for closing the slit 10 after the filler 14 is cured. That is, when constructing the reinforcing structure according to the present embodiment, it is not necessary to remove the mold after the filler 14 is cured.

  In addition, the dimension of the board | plate material 15 is larger than the dimension of the opening part 10a of the slit 10, and the back surface peripheral part of the board | plate material 15 which has blocked the opening part 10a has covered the circumference | surroundings of the opening part 10a. But you may make the dimension of the board | plate material 15 smaller than the dimension of the opening part 10a of the slit 10. FIG. In this case, the plate member 15 can be fitted inside the slit 10 so that the surface of the plate member 15 and the inner surface of the side wall W1 can be flush with each other.

(Embodiment 3)
Hereinafter, a third embodiment of the reinforcing structure of the present invention will be described in detail with reference to the drawings. But the reinforcement structure which concerns on this embodiment has a basic structure in common with the reinforcement structure which concerns on 1st Embodiment. Therefore, only differences from the reinforcing structure according to the first embodiment will be described below, and descriptions of common structures will be omitted as appropriate. In addition, the same reference numerals are used for the same components as those already described, and a duplicate description is omitted.

  In the reinforcing structure according to the present embodiment, as shown in FIG. 7, a steel plate 23 as a reinforcing member is disposed inside the slit 10, and a filler 14 is filled inside the slit 10. . Specifically, a bracing steel plate 23 extending along a diagonal line of the slit 10 is disposed inside the slit 10. In the illustrated steel plate 23, a portion extending along one diagonal line of the slit 10 and a portion extending along the other diagonal line are integrally formed, but separate steel plates constituting each portion are illustrated. You may combine with the shape which is done. In this case, separate steel plates combined in a shape as shown in the figure may be integrated in advance and placed inside the slit 10, or separate non-integrated steel plates may be placed inside the slit 10. Each may be arranged and combined into a shape as illustrated in the inside of the slit 10. In any case, the steel plate 23 is lighter than a rectangular plate-shaped steel material having a size similar to the size (height × depth) of the slit 10, and is easy to handle on site. In particular, when separate steel plates that are not integrated are combined in the shape shown in the inside of the slit 10, each steel plate is small in size and light in weight, so that handling on the site is extremely easy.

  Furthermore, a plurality of through holes may be formed in the steel plate 23 so that the filler 14 filled in the slit 10 flows from the front surface side to the back surface side of the steel plate 23 or from the back surface side to the front surface side. . When a plurality of through holes are formed in the steel plate 23, the filler 14 filled in the slit 10 flows from the front side to the back side of the steel plate 23 or from the back side to the front side through the through hole, and passes through the inside of the slit 10. Fill without gaps. And after the filler 14 hardens | cures, the filler 14 and the steel plate 23 are integrated firmly. In addition, the shape of the steel plate 23 is not limited to the illustrated shape, and can be changed as appropriate.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, although the slit 10 in the said embodiment was newly formed, embodiment with which the reinforcement member was arrange | positioned inside the slit using the crack etc. which generate | occur | produced naturally is also contained in the scope of the present invention. For example, an embodiment in which a reinforcing member is disposed inside a slit formed by widening the induction joint is also included in the scope of the present invention.

  Moreover, in the said embodiment, the same reinforcement structure was provided in the some reinforcement location on one side wall. However, an embodiment in which different reinforcing structures are provided at a plurality of reinforcing points on one side wall is also included in the scope of the present invention. For example, the embodiment in which the reinforcing structure shown in FIG. 3 is provided in the reinforcing part 3a shown in FIG. 2 and the reinforcing structure shown in FIG. It is included in the scope of the invention. Further, the reinforcing portions 4a and 4b shown in FIG. 2 are provided with the reinforcing structure shown in FIG. 3, and the reinforcing portion 4c is provided with the reinforcing structure shown in FIG. Are also included within the scope of the present invention.

  Moreover, although the width | variety of the slit 10 in the said embodiment was constant, embodiment which a width | variety expands or shrinks gradually along a depth direction is also contained in the scope of the present invention. Furthermore, embodiments in which the inner surface of the slit 10 is roughened are also included in the scope of the present invention.

1a, 1b Box culvert W1, W2 Side wall T Top plate B Bottom plate 10 Slit 13 Fiber reinforcing member 14 Filler 23 Steel plate

Claims (4)

A reinforcing structure for a reinforced concrete structure,
A slit formed in the reinforced concrete structure from the inner surface side toward the outer surface side;
A reinforcing member disposed in the slit;
A filler filled in the slit in which the reinforcing member is disposed,
A reinforcing structure for a reinforced concrete structure, wherein the reinforcing member is provided with a plurality of through holes.   The reinforcing structure for a reinforced concrete structure according to claim 1, wherein the reinforcing member is a fiber reinforcing member knitted in a lattice shape with high-strength fibers.   The reinforcing structure for a reinforced concrete structure according to claim 1, wherein the reinforcing member is a steel plate.   The reinforcing structure for a reinforced concrete structure according to claim 3, wherein the steel plates are arranged in braces in the slit.

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