JPH08333900A - Structure and method for repairing concrete building frame - Google Patents

Abstract

PURPOSE: To ensure sufficient adhesive strength for repairing material in adhesion to a concrete building frame without using expensive reinforcing bars while reducing the thickness for chipping, and to ensure sufficient strength for a part where additional casting is made. CONSTITUTION: The bottom of a concrete building frame 10 is chipped (a), and an anchorage member 14 is driven almost perpendicularly into the bottom of the concrete building frame 10. Then, a grid 22 is stretched, opposite to the entire face of the chipped surface 12, and a hexagonal nut 18 with a vane member 16 fixed in parallel therewith is screwed into the projecting part of the anchorage member 14 and a wood-concrete beam 20 is screwed (b) onto the lower end of the anchorage member 14. After that a form 24 is erected, being in contact with the underside of the wood-concrete beam 20. After the form 24 is erected, a repairing material 30 such as concrete or mortar is placed (c) into a space between the form 24 and the chipped surface 12. After hardening of the repairing material 30, the form 24 is removed and the wood-concrete beam 20 is removed after the surplus length of the anchorage member 14 is cut, and an appropriate surface treatment is applied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a repair structure for a concrete skeleton and a repair method.

[0002]

2. Description of the Related Art In the case of repairing an existing concrete skeleton such as a bridge, it is common practice to struck the surface of the concrete skeleton and additionally strike a repair material such as concrete or mortar. In this case, as shown in FIG. 3, the concrete frame 1 has a large suspension thickness (thickness of the reinforcement portion 2) t as shown by the wavy line in the figure, and the reinforcement portion 2 of the repair material is increased.
Although it is desirable to reinforce the reinforcing bar 3, if the thickness t of the reinforcement is slightly larger than the diameter of the reinforcing bar 3, the reinforcing bar 3 cannot be reinforced, and therefore the reinforcement part is formed only by the repair material. 2 must be installed.

[0003]

However, even when the reinforcing bar 3 is laid in the reinforcing part 2, the reinforcing part 2 does not have a sufficient thickness so that the thickness t of the reinforcing part 2 is several tens mm or less. In this case, the covering thickness of the reinforcing bar 3 cannot be sufficiently secured, and as a result, rust may be generated in the reinforcing bar 3 due to salt damage or the like. Therefore, a reinforcing bar having corrosion resistance such as epoxy resin coated reinforcing bar or stainless steel reinforcing bar Therefore, there is a problem that the material cost is high and the economy is poor.

Further, when repairing only the repair material without arranging the reinforcing bars 3, there is an advantage that the chipping work is easy, but on the other hand, cracks occur on the surface of the repair material and the concrete skeleton 1 There is a risk that the repair material will have a weak adhesive force to peel off.

The present invention solves the above-mentioned problems, and while the thickness of the chip can be reduced, the adhesive strength of the repairing material to the concrete skeleton in the finished state is sufficient without using expensive reinforcing bars. It is an object of the present invention to provide a repairing structure and a repairing method for a concrete skeleton, which can be ensured at the same time and can sufficiently secure the strength of the overstretched portion.

[0006]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the structure of the present invention is a repair structure for a concrete skeleton in which a repair material is placed on the flank of the concrete skeleton.
Anchor members that are driven into the fishing surface at a predetermined pitch, locking members that are locked to the protrusions of the anchor members, and blade members that are fixed to the locking members and that extend in the surface direction of the fishing surface. And a projecting portion, a locking member, and a blade member of the anchor member from the fishing surface are integrated with the repair material (claim 1).

In this case, it is possible to dispose a grid-like grid so as to face the flapping surface and press it by the locking member (claim 2).

Further, according to the method of the present invention, the surface of the concrete skeleton is suspended, a plurality of anchor members are driven into the suspension surface at a predetermined pitch, and the protrusions of the anchor members extend in the plane direction of the suspension surface. After locking the locking member with which the long blade member is integrated, the mold is fixedly supported on the tip of the anchor member and a repair material is placed between the mold and the flapping surface. (Claim 3).

In this case, after the grid-like grid is arranged so as to face the hanging surface, the locking member can be locked to the anchor member and the grid can be pressed by the blade member. 4).

[0010]

According to the repair structure of the first aspect, since the anchor member, the locking member, and the blade member are integrated with the repair material, the concrete skeleton and the repair portion are securely fixed to each other.
Further, the blade member functions as a substitute reinforcing material for the reinforcing bar with a fixing length corresponding to the length of the blade member.

If the structure of claim 2 is adopted, in addition to the blade members, the grid also functions as a substitute reinforcing material for the reinforcing bars.

According to the repairing method of the third aspect of the present invention, by simply adding the anchor member and the locking member to the conventional chipping work, support of the formwork, and placement of the repair material, The concrete skeleton and the repaired part can be easily and reliably fixed to each other without arranging the reinforcing bars. Also,
The anchor member serves for fixed support of the formwork.

When the method of the fourth aspect is adopted, the reinforcement of the repaired portion can be further improved easily.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. 1 (a) to 1 (d) show a construction procedure of the present invention for repairing a bottom surface portion of an existing concrete skeleton such as a bridge.

First, (a) shows a state in which the bottom surface portion of the concrete skeleton 10 is hanged by a hang operation to form an uneven hang surface 12. After this hanging work, as shown in (b), the anchor member 14 is
The concrete structure 10 is driven substantially vertically into the suspension surface 12 at a pitch of about 5 to 80 mm.

After the work of driving the anchor member 14, a grid 22 as a reinforcing member is stretched across the entire surface of the flapping surface 12. Then, a hexagonal nut 18 formed by welding and fixing a pair of blade members 16 in parallel with each other is screwed into the protruding portion of the anchor member 14 to prevent the blade member 16 from dropping the grid 22, and further the anchor member 1
Screw the wooden con 20 into the lower end of 4. The grid 22 is
As shown in FIG. 2, carbon fiber or aramid-based, vinylon-based or other fiber-based material having high tensile strength is formed by combining them in a vertical and horizontal lattice pattern, and is used as a reinforcing material to be arranged in a thin struck portion. The diameter is set to a suitable diameter and a lattice pitch that satisfies the design strength of the increased portion and can be supported by the blade member 16. Further, as the blade member 16,
It is preferable to use a wire made of stainless steel, but a wire made of the same material as the grid 22 may be used.
If such a material is used for the blade member 16 and the grid 22, it is suitable for repairing a concrete skeleton that is particularly harsh in use environment conditions such as salt damage.

After that, as shown in FIG.
The form 24 is built so as to contact the lower surface of the. The protruding end of the anchor member 14 penetrates the mold 24, is connected to the thick end material 26 arranged on the lower surface of the mold 24 via the connection fitting 28, and the mold 24 is supported. After installing the formwork 24, the formwork 2
4, the repair material 30 such as concrete or mortar is poured into the space between the surface 4 and the lifting surface 12, and the anchor material 14 and the grid 22 are arranged in the repair material 3
0 is integrated with the concrete skeleton 10. As the repair material, it is desirable to use, for example, a highly fluid concrete Arma # 520 (trade name) manufactured by Mitsubishi Materials Co., in which a shrinkage reducing agent is mixed, or silica sand is mixed in order to reduce the cost. When this concrete is used, a repair structure with high strength and low shrinkage can be obtained. Also,
At the time of placing the repair material, the anchor member 14 has a function as a separator.

After the repair material 30 is hardened, the mold 24 is demolded, the surplus portion of the anchor member 14 is cut, and then the wooden con 20 is removed to perform an appropriate surface treatment. As shown in the figure, the surface of the existing concrete skeleton 10 is covered with the additional-strength portion 32 having a relatively thin thickness t of about several tens of mm, and the repair work is completed.

In the completed state, the vane member 16 and the grid 22 can increase the tensile strength of the reinforcement portion 32 similarly to the reinforcing bar, and are thinner than ordinary reinforcing bars, and particularly the thickness t of the reinforcement portion 32 is thin. It will be the best structure for you. Further, since the grid 22 is adopted, it is less expensive than the epoxy resin-coated rebar, stainless steel rebar, etc., but does not cause corrosion or deterioration due to salt damage or the like.

The present invention is not limited to the above embodiment, and for example, a pair of blade members 16 are welded in parallel to one hexagon nut 18, but the blade member 16 is attached to each hexagon nut 18. There may be one or three or more, and when there are a plurality, each may not be parallel.

Further, the grid 22 can be omitted depending on the strength required for the additional portion t. In this case, the hexagon nut 18 and the wooden connector 20 are previously attached to the anchor member 1.
4 can be screwed in.

[0022]

As described above with reference to the embodiments, according to the repair structure according to the first aspect, the anchor member, the locking member and the blade member serve as the repair material while the thickness of the chip can be reduced. Since the blade member functions as an alternative reinforcing material for the reinforcing bar with a fixed length corresponding to the length of the blade member, the concrete skeleton and the repair section are securely fixed without using expensive reinforcing bar. .

If the structure of claim 2 is adopted, in addition to the blade member, the grid also functions as a substitute reinforcing material for the reinforcing bar.

According to the repairing method of the third aspect, by simply adding the anchor member and the locking member to the conventional chipping work, the support of the formwork and the placing of the repair material, Combined with the fact that it is not necessary to arrange the reinforcing bars and the anchor member serves to fix and support the formwork, the concrete skeleton and the repaired part can be fixed easily and reliably.

When the method of claim 4 is adopted, the reinforcement of the repaired portion can be further improved easily.

[Brief description of drawings]

1A to 1D are cross-sectional views showing a construction procedure of the present invention.

FIG. 2 is a bottom view of FIG. 1 (b).

FIG. 3 is a cross-sectional view showing a conventional repair method.

[Explanation of symbols]

 10 Concrete frame 12 Lifting surface 14 Anchor member 16 Blade member 18 Hexagon nut (locking member) 22 Grid 30 Repair material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Ikuo Ozawa Inventor, Ikuo Ozawa 2-3-8, Higashi Odori, Niigata City, Niigata Prefecture Obayashi Hokuriku Branch (72) Inventor, Yuzo Sasaki 105-1 Kogashi, Komatsu City, Ishikawa Prefecture Japan Road Public Corporation Kanazawa Management Bureau Komatsu Management Office

Claims (4)

[Claims] 1. A structure for repairing a concrete skeleton in which a repair material is cast on a flank of a concrete skeleton, wherein anchor members are driven into the flank surface at a predetermined pitch and projections of the respective anchor members. A locking member to be stopped, and a blade member fixed to the locking member and extending in the surface direction of the flapping surface, the vane member having a predetermined length. A repair structure for a concrete skeleton, which is integrated with the repair material. 2. The repair structure for a concrete skeleton according to claim 1, wherein a grid-like grid is arranged so as to face the flapping surface and is held by the locking member. 3. A surface of a concrete skeleton is hung, a plurality of anchor members are driven into the hang surface at a predetermined pitch, and a blade member of a predetermined length extending in the plane direction of the hang surface is provided on a projection of each anchor member. After locking the fixed locking member, the mold is fixedly supported on the tip of the anchor member and a repair material is placed between the mold and the flapping surface. Repair method. 4. The grid-shaped grid is disposed so as to face the hanging surface, and then the locking member is locked to the anchor member and the blade member presses the grid. The method for repairing a concrete skeleton according to item 3.