JP2002054259A - Concrete structure and construction method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple concrete structure effective for preventing peeling off and drop of a cover part of concrete and a simple construction method for the concrete structure enabling secure construction. SOLUTION: In this concrete structure in which reinforcing bars are arranged, a projecting member protruding in the direction of a surface of the concrete structure is arranged on an outer reinforcing bar or an outer steel member arranged on a surface side of the concrete structure. Moreover, in the construction method for the concrete structure in which reinforcing bars are arranged, a wire having a plurality of projecting members protruding in substantially orthogonal direction to the wire is wound around the reinforcing bar spirally, and the reinforcing bar is arranged on the surface side of the concrete structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a concrete structure and a method for constructing the same.

[0002]

2. Description of the Related Art In a concrete structure, a concrete of a cover portion covering a reinforcing bar arranged on the most surface side is used.
Cracks may occur due to deterioration of concrete or corrosion of reinforcing steel. When the cracked concrete receives a repeated load such as an earthquake, a traffic load, an earth pressure or a water pressure, the concrete may peel off and fall. Particularly, in the case of a bridge or a tunnel crossing a road, if the peeled concrete falls on a person, a car, a train, or the like passing below the concrete structure, it may lead to a serious accident. Conventionally, in order to prevent such peeling and dropping of the cover portion of concrete, steel or plastic mesh has been arranged in the cover portion, or fiber-reinforced concrete has been applied.

[0003]

The above-mentioned conventional concrete structure and its construction method have the following problems. <B> The gap between the formwork and the reinforcing bar for forming the surface of the concrete structure, that is, the covering portion is usually 2.5 to 10 c.
m. It is very difficult to accurately fix the mesh in this gap. <B> By arranging the mesh, the cover portion may not be sufficiently filled with concrete. As a result,
It can also cause cracking and delamination of concrete. <C> In order to prevent only the peeling and dropping of the fogging portion, the fiber reinforced concrete may be filled only in the vicinity of the fogging portion. However, since it is difficult to partially mix fibers, the entire concrete structure is constructed with fiber reinforced concrete. As a result, it is uneconomical because the material costs of unnecessary parts are soared.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and has a simple and effective concrete structure for preventing peeling and falling off of a concrete cover. The purpose is to provide. Also,
An object of the present invention is to provide a method for constructing a concrete structure capable of reliably and reliably constructing a concrete structure for preventing a concrete cover from peeling and falling. The present invention achieves at least one of these objects.

[0005]

In order to achieve the above-mentioned object, a concrete structure according to the present invention is a concrete structure having a reinforcing bar disposed therein, and an outer reinforcing bar disposed on the surface side of the concrete structure. Alternatively, a projection material protruding in the surface direction is disposed on an outer steel material. Further, the method for constructing a concrete structure of the present invention is the method for constructing a concrete structure in which a reinforcing bar is disposed inside, wherein a wire having a plurality of protrusions projecting in a direction substantially perpendicular to the wire is spirally wound around the reinforcing bar, The method is characterized in that the reinforcing bars are arranged on a surface side of a concrete structure.

[0006]

Embodiments of the present invention will be described below with reference to the drawings.

<A> Outer Rebar or Outer Steel The outer rebar 21 is inside the concrete structure 30,
A reinforcing bar disposed on the surface 32 side of the concrete structure, for example, a reinforcing bar disposed outside in the case of a double bar. In the case of a single reinforcing bar, the reinforcing bar arranged only in one step is the outer reinforcing bar 21 here. When steel materials such as an H-shaped steel material and an angle steel material are arranged on the surface 32 side of the concrete structure, these steel materials are outer steel materials.

<B> Fogging part The fogging part 31 refers to the area from the outer reinforcing bar 21 or the outer steel material to the surface 32 of the concrete structure. Usually, a cover portion 31 of 2.5 to 10 cm from the outer reinforcing bar 21 closest to the surface 32 is provided for the purpose of obtaining adhesion between the reinforcing bar and concrete or preventing corrosion of the reinforcing bar.

<C> Projection material The projection material 1 is a wire that protrudes from the outer reinforcing bar 21 toward the surface 32 of the concrete structure. A wire or a fiber made of a metal or a synthetic resin can be used for the protrusion 1. For example, steel wire, steel fiber, glass fiber, polyethylene fiber, polypropylene fiber, aramid fiber, carbon fiber and the like can be used. The protruding material 1 is formed by removing the concrete of the cover 31 from the outer reinforcing bar 3.
As long as it plays a role of mooring at 1, it does not need to project substantially perpendicularly to the outer reinforcing bar 21. In addition, there is no problem even if a part of the protruding material 1 faces the inside reinforcing bar 22 direction. It is preferable that the interval between the protrusions 1 is smaller than the size of the concrete mass that causes cracking, and that the interval does not hinder the filling of the concrete.

<D> Method of Attaching Projection Material FIG. 2 is a perspective view of an embodiment of a reinforcing bar to which the projection material 1 is attached. For example, a plurality of protrusions 1 that protrude in a direction substantially orthogonal to the wire are attached to the wire 11. In this case, the projection 1 is the wire 1
It is preferable to mount them so as to protrude in the same direction with respect to one. The projection 1 may be manufactured by projecting one wire 11 at a predetermined interval. In this case, the protrusion 1 and the wire 11 are continuous with the same material. The wire 11 having the plurality of protrusions 1 is attached by being spirally wound around the reinforcing bar 23.

<E> Arrangement of Reinforcing Bar The reinforcing bar 23 to which the protrusions 1 are attached is arranged as an outer reinforcing bar on the surface side of the concrete structure. For this reason, the arrangement of the reinforcing bars can be performed in the same manner as a normal reinforcing work. After placing the specified reinforcing bars, concrete is poured. Concrete fills the gaps between the projections 1 without any problem.
As a result, the concrete of the cover portion 31 is moored to the outer reinforcing bar 21 or the outer steel material via the protrusion 1. For this reason, even if the direct adhesion of the concrete of the outer reinforcing bar 21 and the cover portion 31 is broken, the separated concrete mass is
It is supported by the projection material 1 and does not fall.

[0012]

The concrete structure and the method of constructing the concrete structure according to the present invention are as described above, and the following effects can be obtained. <B> The structure is simple, with only a protrusion attached to the outer rebar or outer steel. Further, since the concrete at the cover portion is moored by a plurality of protrusions, it is effective in preventing peeling and falling. <B> Just attach the protruding material to the outer reinforcing steel or outer steel material, and the rest is the same as the method of constructing a normal concrete structure. For this reason, there is no difference depending on the skill of construction, and it is possible to easily construct a concrete structure for preventing peeling and falling of the cover portion of concrete. <C> The protrusions are merely arranged at the fogging portions at predetermined intervals. For this reason, it does not hinder the filling of the concrete, and the concrete at the covering portion can be satisfactorily constructed. <D> Only the fogged portion can be reinforced. For this reason, the material cost is low and it is economical.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a concrete structure according to the present invention.

FIG. 2 is a perspective view of an embodiment of a reinforcing bar to which a protrusion is attached.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Projection material 11 ... Wire 21: Outer reinforcing steel 30 ... Concrete structure 32 ... Surface

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shuichi Okamoto 1-25-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo Taisei Corporation F-term (reference) 2D055 CA00 KB05 2E164 AA02 BA02 BA12

Claims (2)

[Claims] 1. A concrete structure in which a reinforcing bar is disposed inside, wherein a projection material protruding in the surface direction is disposed on an outer reinforcing bar or an outer steel member disposed on the surface side of the concrete structure. Concrete structure. 2. A method for constructing a concrete structure in which a reinforcing bar is disposed inside, wherein a wire having a plurality of protrusions projecting in a direction substantially orthogonal to the wire is spirally wound around the reinforcing bar, and the reinforcing bar is wound on the surface of the concrete structure. A method for constructing a concrete structure, characterized by being arranged on the side.