JP6871336B2 - Cover structure - Google Patents

Description

The present invention relates to a novel steel beam covering structure.

When structures such as buildings and civil engineering structures are exposed to high temperatures due to fire or the like, there is a problem that the physical strength of the steel frames constituting these structures drops sharply. On the other hand, there is known a heat-resistant coating structure in which a steel frame is coated with a heat-resistant coating material to delay the temperature rise of the steel frame in the event of a fire and suppress a decrease in the mechanical strength of the steel frame.

In particular, a steel beam having a plurality of through holes in advance is used for piping a duct for air conditioning or ventilation, and the pipe is inserted into the through hole where the pipe needs to be installed. As a heat-resistant coating structure for a steel beam having such a through hole, various forms have been conventionally proposed. This heat-resistant coating structure is constructed in a state where piping is not performed. For example, a first coating member having heat retention such as rock wool inside a through hole provided in a steel beam in advance ( After inserting the fireproof sleeve), a structure provided with the second coating member (for example, Patent Document 1), or a heat-expandable fireproof sheet extending to the outside of both through holes, and then rock wool or the like. There is a structure (for example, Patent Document 2) provided with the fireproof coating material of.

Japanese Unexamined Patent Publication No. 2010-37760 Japanese Unexamined Patent Publication No. 2007-198029

However, in Patent Document 1, it is necessary to mold a refractory sleeve in advance according to the shape of the through hole, and when the steel frame structure is complicated, various forms of molded bodies are required, and the construction thereof may be complicated. is there. Also in Patent Document 2 above, it is necessary to bond a heat-expandable refractory sheet along the inner diameter of the through hole, and the construction thereof may be complicated. Further, in Patent Documents 1 and 2, since the through hole and the covering member on the outer side of the steel frame beam are provided separately, there is a possibility that the heat resistance protection property may be insufficient at the joint or the like. Further, in Patent Documents 1 and 2, the through hole through which the pipe is not inserted remains open, and when a fire occurs, flame or heat may be transmitted from the opened portion to spread the fire.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a covering structure having excellent heat resistance and protection by simple construction as a covering structure of a steel frame beam having a through hole. Is to be.

In order to solve the above problems, as a result of diligent studies, the present inventor has coated both sides of the web plate with a heat-foamable resin sheet so as to close the through holes, and at least in the vicinity of the inside of the opening edge of the through holes, both sides. A notch or a notch or a notch is formed inside the coating structure characterized by forming an integrated region of the heat-foamable resin sheet and further inside the integrated region (near the center of the through hole). The present invention has been completed by coming up with a covering structure characterized by having a perforated portion.

That is, the present invention has the following features.

1. 1. A steel beam covering structure with through holes in the web plate.
Both sides of the web plate are coated with a heat-foamable resin sheet so as to close the through hole, and at least in the vicinity of the inside of the opening edge of the through hole, a region in which the heat-foamable resin sheets on both sides are integrated is formed. ,
The thermosetting resin sheet contains a thermoplastic resin, and a fibrous sheet is laminated on the back surface thereof, and the thickness of the thermosetting resin sheet is 0.2 to 10 mm .
2. A steel beam covering structure with through holes in the web plate.
Both sides of the web plate are coated with a heat-foamable resin sheet so as to close the through hole, and at least in the vicinity of the inside of the opening edge of the through hole, a region in which the heat-foamable resin sheets on both sides are integrated is formed. ,
The thermosetting resin sheet contains a thermoplastic resin, a fibrous sheet is laminated on the back surface, and the thickness of the thermosetting resin sheet is 0.2 to 10 mm.
Further, a covering structure having a notch or an opening inside the integrated region.
3. 3. At least in the vicinity of the inside of the opening edge of the through hole, the thermosetting resin sheets on both sides form a region that is bonded and integrated via an adhesive, integrated by heat fusion, or integrated by a combination thereof. 1. Or 2. The covering structure according to.

Above 1. The covering structure of is a steel beam covering structure having a through hole in the web plate, and both sides of the web plate are coated with a heat-foamable resin sheet so as to close the through hole, and at least the opening edge of the through hole is covered. In the vicinity of the inside, a region in which the heat-foamable resin sheet is integrated is formed. According to such a covering structure, not only the surface of the steel frame beam but also the through holes are closed with the heat-foamable resin sheet, so that excellent heat resistance can be obtained. Further, when piping is required, it is only necessary to form a cut portion or an opening portion in the central portion, and the construction is easy.

Above 2. The covering structure of is a steel beam covering structure having a through hole in the web plate, and both sides of the web plate are coated with a heat-foamable resin sheet so as to close the through hole, and at least the opening edge of the through hole is covered. In the vicinity of the inside, a region where the heat-foamable resin sheet is integrated is formed.
Further, the incision portion or the opening portion is provided inside the integrated region (near the opening center of the through hole). According to such a covering structure, not only the surface of the steel frame beam but also the through holes are completely covered with the heat-foamable resin sheet, so that excellent heat resistance can be obtained. Further, when arranging the pipe, it is easy to construct because only the pipe or the like is inserted into the notch or the opening.

It is a figure which shows an example of a steel beam. It is a perspective view which shows an example of the covering structure of this invention. It is an enlarged view which shows an example of the through hole part of FIG. It is a perspective view which shows an example of the covering structure of this invention. It is an enlarged view which shows an example of the through hole part of FIG. It is a perspective view which shows an example of the covering structure of this invention. It is an enlarged view which shows an example of the through hole part of FIG. It is a perspective view which shows an example of the state in which a pipe is inserted. It is a perspective view which shows an example of the state in which a pipe is inserted. It is a perspective view which shows an example of the state in which a pipe is inserted.

1. 1. Steel beam (H type)
1a. Upper flange 1b. Lower flange 1c. Web 1d. Through hole 1e. Opening edge of through hole 2. Heat-foamable resin sheet 3. Notch 4. Opening part 5. Near the inside of the perforated edge
6. Floor material 7. Piping

Hereinafter, modes for carrying out the present invention will be described.

[Steel beam]
The present invention can be applied to the surface coating of a steel beam constituting a steel structure. As the steel beam, an H-type or I-type steel beam or the like can be used. As the H-shaped or I-shaped steel frame of the present invention, a steel frame having an H-shaped or I-shaped cross section and formed by connecting an upper flange plate and a lower flange plate with a web plate is used. The H-shaped steel frame has a wide flange plate and parallel flange plate inner and outer surfaces. On the other hand, the I-type steel frame usually has a narrow flange plate width and a gradient inside the flange plate.

It is preferable that the surface of the steel beam is rust-proofed in advance. Examples of the rust preventive treatment method include a chemical conversion treatment method such as metal plating, a method of applying a known rust preventive paint, and the like.

FIG. 1 is a perspective view showing an example of a steel beam used in the present invention. FIG. 1 is an H-shaped steel beam, which is formed by connecting an upper flange (1a) and a lower flange (1b) by a web plate (1c), and at least one through hole (1c) is formed in the web plate (1c). It has 1d).

FIG. 2 is a perspective view showing an example of the covering structure of the present invention.
[Thermal foamable resin sheet]
The heat-foamable resin sheet (2) of the present invention foams when the ambient temperature reaches a predetermined foaming temperature due to a fire or the like to form a carbonized heat insulating layer. By closing the through hole with such a heat-foamable resin sheet (2), it has flame-shielding property, and in the event of a fire, a carbonized heat insulating layer can be formed to close the through hole, thus providing high heat resistance. Can be demonstrated. The heat-foamable resin sheet (2) preferably contains a resin component, a flame retardant, a foaming agent, a carbonizing agent, and a filler as constituent components. Of these, the resin component is a vinyl resin, a polystyrene resin, a polypropylene resin, an acrylic resin, a polyamide resin, a polyurethane resin, a thermoplastic resin such as vinyl acetate resin, or the like, and the flame retardant is ammonium polyphosphate or the like. Examples of the agent include melamine, dicyandiamide, azodicarbonamide and the like, examples of the carbide include pentaerythritol and dipentaerythritol, and examples of the filler include titanium dioxide and the like.

The blending ratio of each component is preferably 50 to 1000 parts by weight of the flame retardant, 5 to 500 parts by weight of the foaming agent, 5 to 600 parts by weight of the carbonizing agent, and filling with respect to 100 parts by weight of the resin component in terms of solid content. 10 to 300 parts by weight of the agent. The thickness of the heat-foamable resin sheet (2) may be appropriately set depending on the application site and the like, but is preferably about 0.2 to 10 mm, more preferably about 0.5 to 6 mm.

Further, the heat-foamable resin sheet (2) of the present invention may be composed only of a sheet containing the above-mentioned constituent components, but it is preferable that a fibrous sheet is laminated on the back surface (steel frame side). Thereby, the effect of preventing the formed carbonized heat insulating layer from falling off can be enhanced.

Examples of such a fibrous sheet include a sheet containing organic fibers, inorganic fibers and the like.

Examples of the organic fiber include pulp fiber, polyester fiber, polypropylene fiber, aramid fiber, vinylon fiber, polyethylene fiber, polyarylate fiber, PBO fiber, nylon fiber, acrylic fiber, vinyl chloride fiber, cellulose fiber and the like, or their weaving. Examples include cloth and non-woven fabric. The organic fiber may be such that it melts in a temperature range of about 150 ° C. to become a liquid state, but it is preferable that the organic fiber does not melt in such a temperature range.

Examples of the inorganic fibers include rock wool, glass fibers, silica fibers, silica-alumina fibers, carbon fibers, silicon carbide fibers and the like, woven fabrics thereof, non-woven fabrics and the like, and fine metal wires such as iron and copper. Such an inorganic fiber does not melt even when heat is applied, further acts as a reinforcing material, and can hold a foamed carbonized heat insulating layer, so that it is excellent in the effect of preventing the H-shaped steel frame (1) from falling off. In particular, if the inorganic fibers have a network structure, the heat-foamable resin sheet (2) and the carbonized heat insulating layer formed by applying heat to the heat-foamable resin sheet (2) can be reinforced more efficiently, and the H-shaped steel frame (1) ) Can be prevented from falling off, which is preferable.

The fibrous sheet is a composite sheet composed of inorganic fibers and organic fibers, in which the inorganic fibers are arranged in a mesh pattern, and an organic fiber woven fabric or a non-woven fabric is laminated on at least one (one surface) thereof. It is preferable that a part or all of the mesh of the inorganic fibers is covered with the organic fibers. By combining the inorganic fiber and the organic fiber, the molten component due to heat is adsorbed, and it is possible to prevent the seam portion from peeling off. Further, if the mesh is closed with organic fibers, the network structure of the inorganic fibers does not easily collapse during the production of the heat-foamable resin sheet (2), and the resin sheet (2) can be easily produced.

An example of the covering structure of the present invention is shown in FIG. FIG. 2 shows an example in which an H-shaped steel frame (1) having a through hole is coated with a heat-foamable resin sheet (2). The following examples can be applied to the I-type steel frame as well as the H-type steel frame (1).

In the covering structure of the present invention, a plurality of heat-foamable resin sheets (2) are provided in the longitudinal direction of the H-shaped steel frame (1) so as to close the through hole (1d) of the H-shaped steel frame (1). .. The joint portion between the heat-foamable resin sheets (2) may be abutted or have an overlapping portion, but it is preferable to have an overlapping portion. Further, the heat-foamable resin sheet (2) may be coated in two or more layers according to the desired heat resistance. In the present invention, when the surface of the H-shaped steel frame (1) is coated with the heat-foamable resin sheet (2), it is preferable to use an adhesive.

The adhesive in the present invention includes, for example, water-dispersible type, water-soluble type, and solvent type adhesives mainly made of acrylic resin, silicon resin, epoxy resin, vinyl resin, phenol resin, polyester resin, urethane resin, paraffin, and the like. Known agents and the like can be used. If necessary, a flame retardant, a foaming agent, a carbonizing agent, a filler, or the like, which is blended in the above-mentioned thermosetting resin sheet, can be added to the adhesive. Further, in the present invention, the adhesive also includes a pressure-sensitive adhesive.

FIG. 3 is an enlarged cross-sectional view of the through hole portion of FIG.
As shown in FIG. 3, in the coating structure of the present invention, both sides of the web plate of the steel beam are coated with a heat-foamable resin sheet so as to close the through hole, and at least inside the opening edge (1e) of the through hole. In the vicinity (5), the heat-foamable resin sheets (2) on both sides are integrated. The region where the heat-foamable resin sheet (2) is integrated may be appropriately set, but preferably a region of 5 mm or more (more preferably 10 mm or more) inward from the opening edge (1e) of the through hole (1d). Therefore, the entire surface of the through hole (1d) may be integrated. In particular, in the case of completely closing the through hole, it is preferable that the entire surface of the through hole (1d) is integrated. As a result, the opening edge (1e) of the through hole (1d) is covered with the heat-foamable resin sheet (2), so that the heat resistance can be improved. Examples of the method of integrating the thermosetting resin sheet (2) include a method of adhering and integrating via an adhesive, a method of integrating by heat fusion, and the like, and even if these methods are combined. Good.

FIG. 4 is a perspective view showing another example of the covering structure of the present invention.

The covering structure of FIG. 4 has a notch (3) on the inner side (near the center of the through hole) than on the inner side (5) of the opening edge (1e) of the through hole (1d). .. Further, FIG. 5 is an enlarged cross-sectional view of the through hole portion of FIG.

As shown in FIG. 5, in this embodiment, the cut portion (3) is provided inside (near the center of the through hole opening) of the inside (5) of the through hole opening edge (1e). The shape of the notch (3) is not particularly limited as long as the notch is formed to the extent that the pipe to be arranged can be inserted. When making a cut, it is preferable that the distance from the opening edge (1e) of the through hole (1d) to the end of the cut is at least 5 mm (preferably 10 mm or more). Within such a range, it has flame-shielding properties, and in the event of a fire, a carbonized heat insulating layer can be formed to close the through holes, so that high heat-resistant protection can be exhibited. When making a cut in the heat-foamable resin sheet (2), a cutter, a knife or the like may be used.

FIG. 6 is a perspective view showing another example of the covering structure of the present invention.

The covering structure of FIG. 6 has an opening portion (4) on the inner side (near the opening center of the through hole) than the inner vicinity (5) of the opening edge (1e) of the through hole. Further, FIG. 7 is an enlarged cross-sectional view of the through hole portion of FIG.

As shown in FIG. 7, in this embodiment, the opening portion (4) is provided inside (near the opening center of the through hole) from the inner vicinity (5) of the opening edge (1e) of the through hole. The shape of the opening portion (4) may be any shape such as a circular shape, an elliptical shape, a polygonal shape, etc., and the size thereof is smaller than the through hole (1d) of the steel frame beam and is arranged. The size of the pipe may be large enough to be inserted. In the present invention, the distance from the opening edge (1e) of the through hole (1d) of the steel frame beam to the cut surface of the heat-foamable resin sheet (2) is at least 5 mm or more (preferably 10 mm or more). It is preferable that the gap with the pipe is small. In the case of such a range, it has a flame-shielding property, and in the event of a fire, a carbonized heat insulating layer can be formed to close the through hole, so that high heat resistance protection can be exhibited. The heat-foamable resin sheet (2) may be cut (hollowed out) by using a cutter, a knife, or the like.

FIG. 8 shows a state in which the pipe (7) is inserted from the cut portion (3) of the heat-foamable resin sheet (2).
FIG. 9 shows a state in which the pipe (7) is inserted through the opening portion (4) of the heat-foamable resin sheet (2).

The method of constructing the covering structure of the present invention is not particularly limited as long as the covering structure can be obtained, but for example,
The first step of coating both sides of a steel beam having a through hole in a web plate with a heat-foamable resin sheet via an adhesive layer, respectively.
The second step of integrating the heat-foamable resin sheets on both sides, at least in the vicinity of the inside of the opening edge of the through hole.
Construction methods including.

Also, when inserting a pipe through the through hole,
Examples of the third step include a construction method including a step of forming a cut portion or an opening portion in the heat-foamable resin sheet inside the vicinity of the inside of the opening edge of the through hole. In the present invention, the third step may be performed before the second step, or the second step may be repeated after the third step.

In the first step, the entire surface of the steel beam (so as to close the through hole) is covered with a heat-foamable resin sheet.
In the second step, at least the heat-foamable resin sheet near the inside of the opening edge (1e) of the through hole (1d) (5) is integrated. At this time, when integrating using an adhesive, it can be performed at the same time as the first step. Further, in the case of integration by heat fusion, it is preferable to use an iron, a heat gun or the like.
In the third step, a notch is formed in the heat-foamable resin sheet near the center of the through hole, or an opening smaller than the through hole of the steel beam is formed so that the pipe can be inserted.

According to the above-mentioned construction method, in a steel beam having a through hole, it is not necessary to treat the through hole in advance, and a fireproof coating can be performed by a simple method. In particular, as shown in FIG. 10, in a steel beam having a plurality of through holes, it is possible to insert the pipe only through the through hole where the pipe is required to be installed, and to close the other through holes with a heat-foamable resin sheet. Therefore, a coated structure having excellent heat resistance can be obtained by simple construction.

Specific examples are shown below.
(Manufacturing of heat-foamable resin sheet)
A mixture containing 100 parts by weight of acrylic resin, 90 parts by weight of melamine, 90 parts by weight of dipentaerythritol, 320 parts by weight of ammonium polyphosphate, and 100 parts by weight of titanium oxide is kneaded with a pressure kneader set at a temperature of 120 ° C. and heated. After preparing the kneaded material for the foamable resin sheet, the kneaded material was laminated on the glass non-woven fabric and processed into a sheet shape by a rolling roller to prepare a heat-foamable resin sheet (450 mm × 1200 mm) having a thickness of 1.5 mm.

(Test Example 1)
An H-shaped steel frame (H400 × 200 × 8 × 13 mm, length 1200 mm, through hole φ200 mm) was installed on the floor plate (ALC plate). The glass non-woven fabric side of the produced thermosetting resin sheet was the H-shaped steel frame side, and the thermosetting resin sheet was attached with an acrylic adhesive so as to close the through holes. Further, the joint portion between the thermosetting resin sheets was attached with an acrylic adhesive so that the overlapping width was 20 mm. At the same time, the heat-foamable resin sheets on both sides were integrated in the entire area of the through-hole portion.
Next, a cut portion was formed in the vicinity of the center of the through hole (the distance from the opening edge of the through hole to the end of the cut was 20 mm). From the above, the covering structure illustrated in FIG. 4 was obtained.
A sleeve tube (spiral tube, φ100 × 1000 mm) was inserted into the through hole portion of the covering structure as a test body. The prepared test piece was subjected to a heating test for 1 hour according to the standard heating curve of ISO834. As a result, a uniform carbonized heat insulating layer was formed even in the through hole portion, and good heat resistance protection performance was exhibited.

(Test Example 2)
An H-shaped steel frame (H400 × 200 × 8 × 13 mm, length 1200 mm, through hole φ200 mm) was installed on the floor plate (ALC plate). The glass non-woven fabric side of the produced thermosetting resin sheet was the H-shaped steel frame side, and the thermosetting resin sheet was attached with an acrylic adhesive so as to close the through holes. Further, the joint portion between the thermosetting resin sheets was attached with an acrylic adhesive so that the overlapping width was 20 mm. At the same time, the heat-foamable resin sheets on both sides were integrated in the entire area of the through-hole portion.
Next, a circular opening portion was formed in the vicinity of the opening center of the through hole (distance from the opening edge of the through hole to the opening portion was 20 mm). From the above, the covering structure illustrated in FIG. 6 was obtained.
A sleeve tube (spiral tube, φ100 × 1000 mm) was inserted into the through hole portion of the covering structure as a test body. The prepared test piece was subjected to a heating test for 1 hour according to the standard heating curve of ISO834. As a result, a uniform carbonized heat insulating layer was formed even in the through hole portion, and good heat resistance protection performance was exhibited.

Claims (3)

A steel beam covering structure with through holes in the web plate.
Both sides of the web plate are coated with a heat-foamable resin sheet so as to close the through hole, and at least in the vicinity of the inside of the opening edge of the through hole, a region in which the heat-foamable resin sheets on both sides are integrated is formed. ,
The thermosetting resin sheet contains a thermoplastic resin, and a fibrous sheet is laminated on the back surface thereof, and the thickness of the thermosetting resin sheet is 0.2 to 10 mm . A steel beam covering structure with through holes in the web plate.
Both sides of the web plate are coated with a heat-foamable resin sheet so as to close the through hole, and at least in the vicinity of the inside of the opening edge of the through hole, a region in which the heat-foamable resin sheets on both sides are integrated is formed. ,
The thermosetting resin sheet contains a thermoplastic resin, a fibrous sheet is laminated on the back surface, and the thickness of the thermosetting resin sheet is 0.2 to 10 mm.
Further, a covering structure having a notch or an opening inside the integrated region. At least in the vicinity of the inside of the opening edge of the through hole, the thermosetting resin sheets on both sides form a region that is bonded and integrated via an adhesive, integrated by heat fusion, or integrated by a combination thereof. The covering structure according to claim 1 or 2, wherein the coating structure is characterized by the above.

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