JP2013159948A - Plate-like structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a plate shape even when repeatedly receiving a load, and to prevent dissipation of concrete pieces generated from a broken skeleton.SOLUTION: A floor slab 1 is provided which has a configuration where the surface of a concrete plate-like skeleton 2 whose plate surface is repeatedly subjected to the action of a load is coated with a resin reinforcing film 3, the reinforcing film 3 is made of a compound formed by chemical reaction between an isocyanate and a curing agent consisting of at least one of a polyol and an amine, and the reinforcing film 3 is provided on the upper surface 2a and lower surface 2b of the skeleton 2 repeatedly receiving a load.

Description

  The present invention relates to a plate-like structure in which a plate-like casing made of concrete is reinforced.

  Conventionally, concrete structures to which repeated loads are applied include floor slabs for vehicles such as automobiles and trains, warehouses to which shaking such as earthquakes acts, side walls and floor slabs of buildings such as factories (for example, patent documents) 1). Many of these concrete structures are reinforced concrete structures, and some concrete structures are reinforced with reinforcing bars or steel frames to increase the rigidity of the walls.

JP 2004-360337 A

However, the above-described floor slab is subjected to repeated loads due to traveling of an automobile or a train, and the concrete on the floor surface of the floor slab is peeled off, and this concrete piece is dissipated. For example, there is a problem that concrete fragments that have been destroyed and scattered on the road may interfere with vehicle travel or cause the concrete fragments to jump off.
In the case of a concrete building, the side walls and the floor slab are cracked by aftershocks that repeatedly occur after a large earthquake, and there is a problem that the concrete piece generated by the destruction falls. Especially on the side wall, if the aftershocks continue repeatedly, the shape of the side wall itself can no longer be maintained, and the independence of the side wall may be lost and the building may collapse, so there is room for improvement in these respects.

  The present invention has been made in view of the above-described problems, and can retain a plate shape even when repeatedly subjected to a load, and can prevent a concrete piece from escaping from a destroyed casing. The purpose is to provide.

  In order to achieve the above object, in the plate-like structure according to the present invention, a resin-made reinforcing coating film is coated on the surface of a plate-shaped casing made of a concrete structure in which a load is repeatedly applied to the plate surface. Is characterized by comprising a compound formed by a chemical reaction between an isocyanate and a curing agent comprising at least one of a polyol and an amine.

  In the present invention, a reinforcing coating film composed of a compound formed by a chemical reaction between isocyanate and at least one of a polyol and an amine has a high shear adhesion, a high bending tensile strength, and an elongation. It is a synthetic resin with high performance and excellent mechanical properties (strength, elongation), and has a high strength of, for example, about 10 to 25 MPa and a large breaking elongation (elongation deformation performance) of, for example, 200% or more. For this reason, even if the deformation of the housing reaches the plastic region, the reinforcing coating film stretches and deforms following the large deformation of the housing, so that the energy absorption performance according to the deformation of the housing is exhibited by the reinforcing coating film. Therefore, it is possible to provide a plate-like structure that can cope with repeated loads.

Even if the deformation of the frame reaches the plastic zone due to repeated loads and the concrete is destroyed, the reinforcing coating does not break even if it extends, and the surface of the casing is covered with the reinforcing coating Is maintained. Thereby, dissipation of the concrete piece of a housing is prevented, and the self-supporting shape is hold | maintained, without a housing falling down or collapsing. For example, in the case where the frame is a floor slab, the concrete pieces that have been broken due to repeated loading due to the running load of the vehicle are scattered on the floor slab, which inhibits the vehicle from running or the concrete pieces are scattered around. It is possible to prevent an increase in damage.
In addition, since the reinforcing coating film has a deformation resistance, when the plate-like housing is subjected to an impact and is deformed by bending, a force is applied to return the housing to the original shape by the deformation resistance force of the reinforcing coating film. As a result, the housing is slightly returned after being largely bent and deformed, and the final amount of deformation can be suppressed small.

  In addition, according to the plate-like structure of the present invention, it is formed by spraying or applying a reinforcing coating film on the casing, so that it is easier and less expensive to construct than when reinforcing the surface with an iron plate or rubber material. And can be easily constructed even in an existing housing.

  Moreover, in the plate-shaped structure which concerns on this invention, it is preferable that the reinforcement coating film is provided in 2 or more surfaces among the housings.

  Thereby, it will be in the state where 2 or more surfaces of the housing were wrapped with the reinforcement coating film, and the above-mentioned shape maintenance is more effectively exhibited by the effect (lapping effect).

  Moreover, in the plate-shaped structure which concerns on this invention, it is preferable that the reinforcement coating film is provided in the surface of the housing | casing which a load acts repeatedly, and the back surface on the opposite side of a surface.

  In the present invention, the above-described shape retention is effectively exhibited when the casing is destroyed by repeated loads on the front surface of the casing and the back surface on the opposite side.

  Moreover, in the plate-shaped structure which concerns on this invention, it is preferable that the reinforcement coating film is provided in the whole surface of the housing.

  As a result, the entire surface of the casing is encased in the reinforcing coating film, and the above-described shape retention is more effectively exhibited by the effect (wrapping effect).

  According to the plate-like structure of the present invention, even if the case is destroyed by repeated loading, the concrete piece of the case is prevented from dissipating (preventing local destruction), and it maintains its self-supporting shape without falling or collapsing. (Preventing total destruction / holding shape). Therefore, damage caused by the dissipation of concrete pieces can be suppressed.

It is a partially broken perspective view which shows schematic structure of the floor slab by embodiment of this invention. It is sectional drawing of the floor slab shown in FIG. It is a figure which shows the mechanical characteristic of a polyurea resin. It is sectional drawing which shows the structure of the floor slab by a modification. It is a figure which shows the test result by Example 1. It is a figure which shows the test result by Example 2. It is a partial elevation which shows the structure of the plate-shaped structure by other embodiment.

  Hereinafter, a plate-like structure according to an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 and 2, a floor slab 1 (plate-like structure) according to the present embodiment is a structure in which a vehicle such as an automobile or a train travels on an upper surface, and is on the surface of a reinforced concrete frame 2. This is a structure reinforced by coating a reinforcing coating 3 made of a resin having high toughness.

  The casing 2 is a plate-shaped member made of reinforced concrete and having a predetermined thickness dimension. Here, the casing 2 of the present embodiment receives a load repeatedly on the upper surface 2a side as the vehicle travels, and a compressive force acts in the thickness direction (vertical direction).

  The reinforcing coating 3 to be coated on the housing 2 is provided so as to cover the entire upper surface 2a (front surface) and lower surface 2b (back surface) with a predetermined coating thickness (for example, the thickness dimension D shown in FIG. 2 is 4 mm). It has been.

  The above-described reinforcing coating film 3 is a resin coating film applied to the surface of the housing 2 by spraying or using a roller or the like, and by a chemical reaction between isocyanate and a curing agent made of at least one of polyol and amine. Consists of formed compounds. For example, as the reinforcing coating 3, a polyurea resin that is a compound formed by a chemical reaction between an isocyanate and an amine can be used.

  Specifically, the reinforcing coating film 3 is made of a synthetic resin having high mechanical properties (strength and elongation) with high shear adhesion, high bending tensile strength, and high elongation performance. For example, a polyurea resin has mechanical characteristics as shown in FIG. Here, the synthetic resin constituting the reinforcing coating 3 is made of, for example, a resin having a physical property of about 20 MPa (10 to 25 MPa) having a tensile strength of about one tenth of a reinforcing bar and having a breaking elongation of 200% or more. For example, “Swaer AR-100 (registered trademark: manufactured by Mitsui Chemicals, Inc.)” is used. In addition, it is preferable that the thickness dimension D of the reinforcement coating film 3 is 2 mm or more.

  Here, as a construction method for covering the casing 2 of the floor slab 1 with the reinforcing coating 3, the concrete surface to be applied is sufficiently cleaned to remove dust and the like, then a primer is applied, and then the polyurea resin is casing. A predetermined thickness is applied over the entire upper surface 2a and lower surface 2b. Thereby, the layered reinforcing coating film 3 is formed on the housing 2. In addition, application | coating of a primer can also be abbreviate | omitted, or in order to improve the adhesiveness of the reinforcing coating 3 and the housing 2, you may process the surface of the housing 2 so that it may be uneven.

Next, the operation of the floor slab 1 having the above-described configuration will be specifically described.
As shown in FIGS. 1 and 2, in the present embodiment, the reinforcing coating film 3 has excellent mechanical properties (strength and elongation) with high shear adhesion, high bending tensile strength, and high elongation performance. Since it is a synthetic resin, even if the deformation of the housing 2 reaches the plastic region, the reinforcing coating 3 stretches and deforms following the large deformation of the housing 2, so that the energy corresponding to the deformation of the housing 2 by the reinforcing coating 3 Absorption performance is demonstrated. Therefore, the floor slab 1 capable of handling repeated loads can be provided.

  Even if the deformation of the housing 2 reaches the plastic region due to repeated loads and the concrete is destroyed, the reinforcing coating 3 does not break even if it extends, and the surface of the housing 2 is not broken by the reinforcing coating 3. The coated state is maintained. Thereby, dissipation of the concrete piece of the housing 2 is prevented, and the self-standing shape is maintained without the housing 2 falling or collapsing. For example, in the case where the frame 2 is the floor slab 1 as in the present embodiment, the concrete pieces that are broken due to the repeated load due to the running load of the vehicle are scattered on the floor slab 1 and hinder the running of the vehicle. Or increase in damage such as the concrete pieces scattered around.

  Moreover, since the reinforcing coating 3 has deformation resistance, when the impact is applied to the floor slab 1 and the housing 2 is bent and deformed, the housing 2 is returned to its original shape by the deformation resistance force of the reinforcing coating 3. Power works. As a result, the housing 2 is slightly bent and deformed, and then slightly returned, so that the final deformation amount is suppressed to a small value.

  Further, since it is formed by spraying or coating the reinforcing coating 3 on the casing 2, it can be easily and inexpensively constructed as compared with the case where the surface of the floor slab is reinforced with an iron plate or a rubber material. It can be easily constructed even for floor slabs.

  Further, the reinforcing coating 3 of the floor slab 1 is provided on two or more surfaces (here, two surfaces) of the casing 2, and in particular, the upper surface 2a of the casing 2 to which the reinforcing coating 3 repeatedly receives a load, and the lower surface on the opposite side. 2b, the two surfaces of the casing 2 are encased by the reinforcing coating 3, and the above-described shape retention is more effectively exhibited by the effect (wrapping effect).

  As described above, in the plate-like structure (floor slab 1) according to the present embodiment, even if the frame 2 is broken due to repeated loads caused by traveling of the vehicle, the concrete pieces of the frame 2 are prevented from being dissipated (preventing local destruction). It is possible to hold a self-supporting shape without falling or collapsing (preventing overall destruction / holding shape). Therefore, damage caused by the dissipation of concrete pieces can be suppressed.

(Modification)
Next, a modification of the above-described embodiment will be described.
That is, in the above-described embodiment, the reinforcing coating film 3 is provided only on the upper surface 2a and the lower surface 2b of the frame 2 of the floor slab 1, but it is not limited to such a covering range. In the modification shown in FIG. 4, the reinforcing coating 3 is covered over the entire surface of the housing 2, that is, the entire surfaces of the upper surface 2a, the lower surface 2b, and the four side surfaces 2c.
In this case, the entire surface of the casing 2 is encased by the reinforcing coating 3, and the shape retention described above is more effectively exhibited by the effect (wrapping effect).

  Next, test examples (Examples 1 and 2) conducted to support the effect of the floor slab 1 (plate-like structure) according to the above-described embodiment and modification will be described below.

Example 1
In Example 1, a beam member made of reinforced concrete having a rectangular cross section is used as a test body, and a test body 1 in which no polyurea resin is applied to the surface of the beam material, and test bodies 2, 3, and 4 in which a polyurea resin is applied. On the other hand, an impact bending test using a loading device was performed, and the deformation state (cracking or peeling) of the test bodies 1 to 4 in which the application state of the polyurea resin was changed was confirmed.
The beam material of each test body 1 to 4 is a structure having six faces of length 100 mm × width 120 mm and a length dimension of 1200 mm, and concrete of 4 weeks strength and 25 N / mm ² is used. Furthermore, D13 (core cover 35 mm) and shear reinforcement D6 are used inside the test bodies 1 to 3. And as loading conditions, the test bodies 1-4 are arrange | positioned with the length direction turned to a horizontal direction, and the load of 30 kN is applied to the center part of the length direction of the test bodies 1-4 quasi-static. Loading was applied at a speed of 0001 m / s.

  Here, the test body 1 is obtained by applying a polyurea resin having a coating thickness of 4 mm on the six surfaces of the beam material, and the test body 2 is obtained by applying a polyurea resin having a coating thickness of 2 mm on the six surfaces of the beam material. The body 3 is a beam material in which the length direction is oriented in the horizontal direction and a polyurea resin having a coating thickness of 2 mm is applied only to the upper and lower surfaces (when the polyurea resin is not applied to the four side surfaces). The test body 4 does not have a reinforcing bar and a polyurea resin.

FIG. 5 shows the bending test results of the test bodies 1 to 4 in which the horizontal axis is the deformation amount δ (mm) of the loading point and the vertical axis is the load P (kN).
As shown in FIG. 5, in the case of the test body 1, the specimen was broken when the deformation amount δ was approximately 40 mm, and a concrete piece was generated at the broken portion.
In the case of the test body 2 in which 2 mm of polyurea resin is applied to the upper and lower surfaces, the deformation δ is broken at about 60 mm. (Wrapping effect) and a certain shape retention effect was confirmed.
Moreover, it was confirmed that the load of 30 kN was maintained even after yielding (right side from the yield point P1 in FIG. 5) in the test bodies 1 and 2 in which polyurea resin was applied to the entire surface of the beam (six sides). From this, it can be seen that the wrapping effect is large and the shape retention effect is high.

(Example 2)
Next, in Example 2, a polyurea resin was applied to 6 surfaces of the beam material in Example 1 with a coating thickness of 2 mm, and a test in which the loading speed was changed by an impact bending test was performed, and the deformation state (cracking or peeling) was performed. confirmed.
The first test T1 has a loading speed of 4 m / s (high speed), the second test T2 has a loading speed of 0.5 to 1 m / s (medium speed), and the third test T3 has a loading speed of 0.1 to 0.5 m / s. The loading speed was s (low speed), and the fourth test T4 was a loading speed of 0.0001 m / s (quasi-static speed).

FIG. 6 shows the bending test results in the first test T1 to the fourth test T4 in which the horizontal axis is the deformation amount δ (mm) of the loading point and the vertical axis is the load P (kN).
As shown in FIG. 6, it can be seen that the quasi-static maximum load is maintained even after yielding in each of the tests T1 to T4. From this, when polyurea resin is applied over the entire six surfaces of the beam material, it can be confirmed that the quasi-static maximum load is maintained regardless of the loading speed. At this time, the specimen of the beam material was greatly deformed and bent at an angle of about 5 degrees. However, the concrete piece was not generated and the shape as the beam material was maintained. Thus, it was confirmed that the beam material coated with polyurea resin is effective against impact and continuous force and can prevent the generation of concrete pieces.

The embodiment of the plate-like structure according to the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the scope of the present invention.
For example, in the present embodiment, the floor slab 1 is applied as a plate-like structure, but is not limited to this, and can be applied to other forms of plate-like structures.
For example, as shown in FIG. 7, the present invention can be applied to a building 4 (plate-like structure) that receives repeated loads due to aftershocks after a large-scale earthquake, for example. In this case, the outer surface 41 a and the inner surface 41 b are covered with the reinforcing coating 3 on the side wall 41, and the upper surface 42 a and the lower surface 42 b are covered with the reinforcing coating 3 on the floor slab 42.
Furthermore, not only the side walls and floor slabs of buildings, but also beams and columns subjected to repeated loads may be the target of the reinforcing coating.

  Moreover, in the case of the above-mentioned building 4 shown in FIG. 7, since the function which prevents the water leakage to the inside is also calculated | required, it is made to apply | coat the reinforcement coating 3 across a joint part, and coat | cover a joint part. It is preferable to provide it. As a result, even if the joint portion is broken and the joint portion is once greatly opened, a force in a direction returning by the deformation resistance force of the reinforcing coating film 3 (that is, a direction in which the opened joint portion is closed) acts. The final opening amount of the joint portion can be suppressed to be small.

  Further, in the reinforcing coating 3, it is also possible to mix a nonflammable mixed material in which, for example, glass pieces, glass fibers, glass frit, etc. are dispersed, into the polyurea resin. Alternatively, the mixed material may be a nonflammable material other than glass, such as concrete, brick, tile, asbestos slate, steel, aluminum, mortar, or plaster.

  In the above-described embodiment, a polyurea resin made of a compound formed by a chemical reaction between an isocyanate and an amine is used as the reinforcing coating film 3, but the present invention is based on a chemical reaction between an isocyanate and a polyol. It is also possible to use a polyurethane resin made of the formed compound as a reinforcing coating film, and it is also possible to use a resin made of a compound formed by a chemical reaction of isocyanate, polyol and amine as a reinforcing coating film. .

  In addition, it is possible to appropriately replace the components in the above-described embodiments with known components without departing from the spirit of the present invention.

1 Floor slab (plate structure)
2 Housing 2a Upper surface (surface)
2b Bottom (back)
3 Reinforcing coating 4 Building (plate-like structure)
41 Side wall 42 Floor slab

Claims (4)

The surface of the plate-shaped casing made of concrete, where the load acts repeatedly on the plate surface, is coated with a resin reinforcing coating,
The said reinforcing coating film consists of a compound formed by the chemical reaction of isocyanate and the hardening | curing agent which consists of at least one of a polyol and an amine, The plate-shaped structure characterized by the above-mentioned.   The plate-like structure according to claim 1, wherein the reinforcing coating film is provided on two or more surfaces of the casing.   2. The plate-like structure according to claim 1, wherein the reinforcing coating film is provided on at least a surface of the casing on which a repeated load acts and a back surface opposite to the surface.   The plate-like structure according to claim 1, wherein the reinforcing coating film is provided on the entire surface of the casing.

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