JP2014091669A - Cross-section repairing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fireproof, cross-section repairing material which can obtain excellent workability in performing local restoration.SOLUTION: A fireproof, cross-section repairing material for repairing a structure using a cement composition, contains a polymer cement mortar including cement and a polymer, and an organic fiber, with a 15 tap flow value of the mortar being less than 170 mm.

Description

  The present invention relates to a cross-sectional repair material having fire resistance.

  When a concrete (a type of cement composition) structure is heated by a fire or the like and becomes high temperature, an explosion phenomenon occurs in which the surface layer of the concrete structure peels off and falls. For this reason, a method of protecting the concrete structure from high heat by providing a fireproof layer made of a fireproof coating material on the surface layer portion of the concrete structure is used (for example, see Patent Document 1).

  In such a fireproof concrete structure, when repairing damage to the surface layer, it is necessary to use a fireproof material (cross-section repair material) in preparation for a fire that may occur again. is there.

JP 2008-297875 A

  In patent document 1 mentioned above, the surface of a concrete structure is coat | covered with the spraying method. However, for example, when performing cross-sectional repair of a small local area, using a large machine such as a spraying system is costly.

  In the spraying method, a material having high fluidity (specifically, a mortar 15-stroke flow value of 170 mm or more) is used as a fireproof coating material. When patching is performed by the plasterer using the same material as this, the repaired portion may flow and good workability may not be obtained.

  This invention is made | formed in view of the above subjects, The objective is providing the fireproof cross-section repair material which can acquire favorable workability, when performing local repair. There is.

In order to achieve such an object, the cross-sectional repair material of the present invention is
A fire-resistant cross-section repair material for repairing a structure using a cement composition,
Polymer cement mortar containing cement and polymer;
Organic fiber,
The mortar has a 15-stroke flow value of less than 170 mm.
According to such a cross-sectional repair material, since fluidity | liquidity is suppressed, when repairing by a plasterer, it is possible to obtain favorable workability.

In such a cross-sectional repair material, the weight ratio of the polymer to the cement is desirably 5% or less.
According to such a cross-sectional repair material, explosion can be suppressed.

It is desirable that such a cross-sectional repair material does not contain a quick setting agent.
According to such a cross-sectional repair material, workability can be improved.

In such a cross-sectional repair material, the organic fiber desirably has a fiber diameter of 50 μm or less and a fiber length of 20 mm or less.
According to such a cross-sectional repair material, explosion can be further suppressed.

In such a cross-sectional repair material, it is desirable that the organic fiber is mixed in a volume ratio of 0.5% or more.
According to such a cross-sectional repair material, explosion can be further suppressed.

ADVANTAGE OF THE INVENTION According to this invention, when performing local repair, it is possible to provide the fireproof cross-section repair material which can acquire favorable workability.

FIG. 3 is an explanatory diagram showing a concrete structure 10. It is a figure which shows a mode that the concrete structure 10 was repaired with the cross-section repair material 16 which concerns on this embodiment.

  Hereinafter, an embodiment of the present invention will be described.

=== Embodiment ===
FIG. 1 is an explanatory view showing a concrete structure 10.
The concrete structure 10 of this embodiment is a structure (for example, a floor) formed using concrete, and has a concrete layer 12 and a fireproof layer 14.

  The concrete layer 12 is formed using, for example, ordinary concrete, and a steel material (H steel, rebar, etc.) (not shown) is disposed inside the concrete layer 12.

  The refractory layer 14 is formed on the surface layer portion (specifically, the cover portion) of the concrete structure 10 to prevent explosion. The fireproof layer 14 of the present embodiment is formed of concrete mixed with organic fibers (organic fiber mixed concrete).

  As shown in FIG. 1, the refractory layer 14 of the concrete structure 10 has local damage 14a at the top. The damage 14a is formed, for example, by partially peeling the refractory layer 14 due to cracking or deterioration. When repairing such concrete damage 14a, polymer cement mortar is usually used. This is because polymer cement mortar has good durability and good adhesion to concrete.

  However, since the polymer cement mortar has low fire resistance, if the damage of the refractory layer 14 is repaired with the polymer cement mortar as in this embodiment, it may be peeled off again in the event of a fire or the like.

  Therefore, in the present embodiment, when repairing the local damage 14a of the refractory layer 14 as described above, a cross-sectional repair material having fire resistance is used.

  FIG. 2 is a diagram illustrating a state in which the concrete structure 10 of FIG. 1 is repaired by the cross-sectional repair material 16 according to the present embodiment. In FIG. 2, parts having the same configuration as in FIG.

As shown in FIG. 2, the damage 14 a of the refractory layer 14 of the concrete structure 10 of FIG.
The cross-sectional repair material 16 is manufactured by blending polymer cement mortar 16a and organic fiber 16b at a predetermined ratio. Thus, fire resistance can be improved by mixing the organic fiber 16b in the polymer cement mortar 16a.

  The polymer cement mortar 16a contains cement and a polymer. In addition, as the polymer content increases, the resistance to explosion decreases. Therefore, in the present embodiment, the polymer content is set to 5% or less by weight ratio to the cement. This increases resistance to explosions.

  The organic fiber 16b is a fibrous material made of an organic material. In the present embodiment, polypropylene fibers are used as the organic fibers 16b. Polypropylene fiber melts and vaporizes at 250 ° C to 500 ° C. In addition, it is desirable to use the organic fiber 16b having a fiber diameter of 50 μm or less and a fiber length of 20 mm or less, and an addition rate of 0.5% or more by volume ratio. By carrying out like this, generation | occurrence | production of an explosion can be suppressed more.

  By the way, if such cross-sectional repair of the local damage 14a is performed, it is costly to use a large machine such as a spraying system. Therefore, in this embodiment, repair is performed by a plasterer. However, in this case, if repair is performed using the same material as the spraying system, there is a possibility that good workability cannot be obtained. For example, in a spraying system, a material having a mortar 15-stroke flow value of 700 mm or more is used, but when repaired by a plasterer using the same material as this, there is a possibility that the repaired portion will flow.

  For this reason, in this embodiment, a material having a smaller fluidity than the material used in the spraying system is used as the cross-sectional repair material 16. Specifically, the cross-sectional repair material 16 of the present embodiment has a mortar 15-shot flow value of less than 700 mm.

  By carrying out like this, since fluidity | liquidity can be suppressed, the workability | operativity at the time of repair by a plasterer can be improved.

  In addition, the material used in the spraying system contains a quick setting agent. The quick setting agent is an admixture for enhancing the hydration action that accelerates the setting time of cement. On the other hand, the cross-sectional repair material 16 of this embodiment does not contain a quick setting agent. For this reason, since hardening time is not accelerated | stimulated, workability | operativity can further be improved.

  As described above, in the present embodiment, when repairing the damage 14a of the refractory layer 14 of the concrete structure 10, the refractory containing the polymer cement mortar 16a containing cement and polymer and the organic fiber 16b. The cross-sectional repair material 16 is used. Further, the mortar 15-stroke flow value of the cross-sectional repair material 16 is less than 170 mm, and is less fluid than the material used in the spraying system. Thereby, when performing local repair by a plasterer, favorable workability can be obtained.

=== About Other Embodiments ===
The above embodiment is for facilitating the understanding of the present invention, and is not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

<Concrete structure 10>
Moreover, in the above-mentioned embodiment, although the concrete structure 10 was a floor, it is not restricted to this. For example, it may be a wall, a pillar, a beam, or the like. It may be other than a building (for example, a tunnel segment).

<About organic fibers>
Moreover, in the above-mentioned embodiment, although the polypropylene fiber was used as the organic fiber 16b, it is not restricted to this. For example, vinylon fiber or polyethylene fiber may be used.

DESCRIPTION OF SYMBOLS 10 Concrete structure 12 Concrete layer 14 Refractory layer 16 Cross-section repair material 16a Polymer cement mortar 16b Organic fiber

Claims (5)

A fire-resistant cross-section repair material for repairing a structure using a cement composition,
Polymer cement mortar containing cement and polymer;
Organic fiber,
And a cross-section repair material characterized by having a mortar 15-stroke flow value of less than 170 mm. The cross-sectional repair material according to claim 1,
A cross-sectional repair material, wherein a weight ratio of the polymer to the cement is 5% or less. The cross-sectional repair material according to claim 1 or claim 2,
A cross-sectional repair material characterized by not containing a quick setting agent. The cross-sectional repair material according to any one of claims 1 to 3,
The organic fiber has a fiber diameter of 50 μm or less and a fiber length of 20 mm or less. The cross-sectional repair material according to any one of claims 1 to 4,
The organic fiber is mixed in a volumetric ratio of 0.5% or more.