JP6776016B2 - Fireproof structure - Google Patents

Description

The present invention relates to a fireproof structure provided in a structural material of a building.

Conventionally, for example, a steel structure disclosed in Patent Document 1 has been proposed as a structure for forming a steel wall, floor, or roof having improved fire resistance while simplifying the structure.

The steel structure disclosed in Patent Document 1 employs a thin plate lightweight shaped steel having a plate thickness of less than 2.3 mm as a base material for attaching the member of the fireproof coating, and constitutes the fireproof coating by including the structural frame and other parts. To do. The steel structure disclosed in Patent Document 1 is said to have improved fire resistance performance by forming a fireproof coating as a wall, floor, or roof including a structural frame and other parts.

JP-A-2010-24811

Here, in the steel structure disclosed in Patent Document 1, rock wool or the like is sprayed on the columns or beams serving as the structural frame, and a fireproof coating material such as rock wool is formed between the columns or beams and the finishing surface material. It is filled. For this reason, in the steel structure disclosed in Patent Document 1, rock wool or the like is filled between the column or beam and the finishing surface material, so that the material cost of the fireproof coating material and the filling of the fireproof coating material are required. There was a problem that the construction cost and the construction period increased.

Further, in the steel structure disclosed in Patent Document 1, it is said that a fireproof coating material for a face material such as gypsum board can be attached to a column or a beam serving as a structural frame instead of a fireproof coating material such as rock wool. .. At this time, in the steel structure disclosed in Patent Document 1, since the fireproof coating material of the face material such as gypsum board is attached in contact with the column or beam, the space between the column or beam and the gypsum board or the like is provided. There is a problem that the air layer is not formed in the gypsum and the fire resistance performance of the structural frame is not sufficiently improved.

Therefore, the present invention has been devised in view of the above-mentioned problems, and an object of the present invention is to suppress the material cost and construction cost of the fireproof coating material, and at the same time, to prevent the fireproof of the structural material of the building. The purpose is to provide a fireproof structure that can sufficiently improve the performance.

The fire-resistant structure according to the first invention is a fire-resistant structure provided in a structural material of a building, and is a steel frame material provided as a structural material such as a beam material or a pillar material and a finishing material provided apart from the steel frame material. A fireproof coating material is provided between the finishing material and the steel frame material in an approaching gap formed by separating the finishing material from the steel frame material at a position closest to the steel frame material. is it not without, the finish as part of Tosakai wall separating proprietary portion of the building, provided a pair on both sides of the Tosakaikabe, the Tosakaikabe a pair of said The steel frame material is provided between the finishing materials, and a hollow gap portion having a space larger than the approach gap portion is formed , and the approach gap on one side surface or both side surfaces heated in the event of a fire in the door boundary wall. An air layer is formed in the portion and the hollow gap portion communicating with the portion .

As for the fireproof structure according to the second invention, in the first invention, the steel frame material is an H-shaped steel having a pair of flanges and a web erected on the pair of flanges, and the flange and the finishing material are used. Is arranged on the side of the steel frame material in a direction substantially orthogonal to each other, and is sandwiched between the pair of the finishing materials.

In the fireproof structure according to the third invention, in the first invention or the second invention, the steel frame material has a pair of flanges and a web erected on the pair of flanges, and separates the pair of flanges from each other. It is characterized in that a narrow H-shaped steel having a smaller member width at each of the flanges is used rather than a member made of the member.

As for the fireproof structure according to the fourth invention, in any one of the first to third inventions, as the finishing material, a fireproof board such as gypsum board, rock wool board, calcium silicate board, ALC board or GRC board is used. It is characterized by that.

According to the first to fourth inventions, since the steel frame material is not provided with the fireproof coating material such as rock wool, the material cost and the construction cost of the fireproof coating material are suppressed so that the fireproof performance is not excessive. At the same time, an air layer is formed in the close gap between the finishing material and the steel frame material, which delays the temperature rise of the steel frame material in the event of a fire and becomes a structural material such as a beam material or a column material. It is possible to sufficiently improve the fire resistance performance of the material.

According to the first to fourth inventions, an air layer is formed in the approaching gap between the finishing material and the steel frame material without providing the fireproof coating material, so that the vibration from the finishing material to the steel frame material is formed. Propagation is suppressed, sound insulation performance on doorway walls, etc. can be improved, and an air layer is formed in the approaching gap between the finishing material and the steel frame material, so that the beam material or column It is possible to easily install the finishing material on one side or both sides of the steel frame material regardless of the construction error of the steel frame material as the structural material such as the material.
Further, according to the first to fourth inventions, the steel frame material is sandwiched between the pair of finishing materials on both side surfaces of the door boundary wall, and the space larger than the approach gap portion in the beam-to-beam direction or the height direction of the steel frame material. Even if a thin wall is provided and the air layer in the approaching gap becomes smaller due to the formation of the hollow gap, the air layer in the hollow gap at a position other than the approaching gap is sufficient. Since it exerts a heat insulating effect, it is possible to suppress heat transfer from one side surface to the other side surface, which is heated in the event of a fire on the doorway wall.

In particular, according to the second and third inventions, narrow H-shaped steel is used as the steel frame material, and the flange of the steel frame material and the finishing material are arranged in a direction substantially orthogonal to each other, whereby a pair of steel frames are used. Even when the steel frame is provided so as to be sandwiched between the finishing materials and fit inside the doorway wall, the fire resistance performance of the steel frame is sufficiently improved, and at the same time, a beam type or a pillar shape made of the steel frame is formed. It is possible to provide a thin-walled doorway wall without causing it.

In particular, according to the fourth invention, the heat transfer from the finishing material to the steel frame material is suppressed by exerting the heat insulating effect on the air layer in the approaching gap while utilizing the heat insulating performance of the finishing material such as gypsum board. This makes it possible to delay the temperature rise of the steel frame material.

It is a perspective view which shows the building which the fireproof structure to which this invention is applied is provided in the structural material. It is a top view which shows the building which the fireproof structure to which this invention is applied is provided in the structural material. It is a side view which shows each floor of the building where the fireproof structure to which this invention is applied is provided in a structural material. It is a front view which shows each floor of the building where the fireproof structure to which this invention is applied is provided in the structural material. It is a perspective view which shows the exclusive part and common part of the building which the fireproof structure to which this invention is applied is provided in the structural material. (A) is a cross-sectional view showing a steel beam between beams of a building to which a fireproof structure to which the present invention is applied is provided on a structural material, and (b) is a cross-sectional view showing the girder steel frame beam. It is a side view which shows the state which the steel beam between the beam of the lower floor and the upper floor is connected to each other by the steel brace in the building which the fireproof structure to which this invention is applied is provided in the structural material. It is a side view which shows the state which the steel frame beam between the lower floor and the upper floor is connected to each other by the wall column in the building which the fireproof structure to which this invention is applied is provided in the structural material. It is a perspective view which shows the joint part of the inter-beam steel frame beam, the girder steel frame beam, and the concrete column in the building where the fireproof structure to which this invention is applied is provided in the structural material. It is a perspective view which shows the fireproof structure to which this invention is applied. (A) is a cross-sectional view showing a steel frame material to be an inter-beam steel frame beam in a fireproof structure to which the present invention is applied, and (b) is a cross-sectional view showing a steel frame material to be a wall column thereof. (A) is a cross-sectional view showing a steel frame material in which a plurality of narrow H-shaped steels are connected in a fireproof structure to which the present invention is applied, and (b) is a finishing material on both sides in the girder direction and the beam-to-beam direction. It is sectional drawing which shows the steel frame material in which. (A) is a cross-sectional view showing a steel frame material in which the flange and the finishing material are arranged in a direction substantially orthogonal to each other in a fireproof structure to which the present invention is applied, and (b) is a sectional view showing the flange and the finishing material substantially parallel to each other. It is sectional drawing which shows the steel frame material arranged so that. (A) is a cross-sectional view showing a finishing material in which an air layer is formed in an approaching gap in a fireproof structure to which the present invention is applied, and (b) is a conventional steel frame structure with a structural frame and a finishing surface material. It is sectional drawing which shows the refractory coating material filled in between. (A) is a cross-sectional view showing an analysis model of the prior art in which the structural skeleton and the finishing face material are in contact with each other, and (b) is a cross-sectional view showing the analysis model of the present invention orthogonal to the weak axis. , (C) are cross-sectional views showing an analysis model of the strong axis orthogonality of the present invention. It is a graph which shows the result of having compared the temperature history with the analysis model of the fireproof structure to which this invention was applied, and the analysis model of the prior art.

Hereinafter, a mode for carrying out the fireproof structure 1 to which the present invention is applied will be described in detail with reference to the drawings.

As shown in FIG. 1, the fireproof structure 1 to which the present invention is applied is mainly provided on the structural material of the building 8 having a hierarchical structure. The fireproof structure 1 to which the present invention is applied is provided in, for example, a building 8 such as a plate-shaped apartment house in which the girder direction X is the longitudinal direction and the beam-to-beam direction Z is the lateral direction. The fireproof structure 1 to which the present invention is applied may be provided in a general building such as a hospital or an office.

The building 8 is surrounded by, for example, a pair of girder outer peripheral portions 81 extending in the girder direction X and a pair of inter-beam outer peripheral portions 82 extending in the inter-beam direction Z as a hierarchical structure having an overall height of about 45 m in the height direction Y. Therefore, it is constructed so that the plane shape becomes substantially rectangular.

The building 8 includes a floor slab 4 that divides each floor of the hierarchical structure, an inter-beam steel beam 5 extending in the inter-beam direction Z, a girder steel beam 6 extending in the girder direction X, and an inter-beam steel beam 5 extending in the height direction Y. A concrete column 7 to which the girder steel beam 6 is joined is provided.

As shown in FIG. 2, the building 8 is provided so as to extend in the girder direction X so that the pair of girder outer peripheral portions 81 are substantially parallel to each other on both sides of the beam-to-beam direction Z, and on both sides of the girder direction X. The pair of inter-beam outer peripheral portions 82 are provided so as to extend in the inter-beam direction Z so as to be substantially parallel to each other.

The building 8 is provided on each floor of the hierarchical structure in which a plurality of exclusive portions P such as dwelling units are arranged side by side in the column direction X. Further, in the building 8, a balcony B that can be used from each exclusive portion P, a passage C for entering and exiting a plurality of exclusive portions P, and the like are provided as the common portion S.

The exclusive portion P is a space exclusively owned by the owner or resident of each dwelling unit or the like. The exclusive portion P is provided with an opening A for entering and exiting the balcony B of the common portion S on one side of the beam-to-beam direction Z, and enters and exits from the passage C of the common portion S on the other side of the beam-to-beam direction Z. Entrance E and the like are provided for this purpose.

The exclusive portion P is separated from the exclusive portion P adjacent to each other in the girder direction X by a door boundary wall D extending in the beam-to-beam direction Z. The door boundary wall D covers the entire surface of the boundary separating the plurality of exclusive portions P adjacent to each other in the girder direction X, for example, a wall thickness of about 200 mm to 300 mm, with a minimum wall thickness of about 180 mm and a standard wall of about 200 mm. It will be provided in thickness.

The common portion S is provided with a balcony B continuously in the column direction X so that the common portion S can pass through each other from the adjacent exclusive portion P in an emergency or the like, and can enter and exit each exclusive portion P at all times. A passage C is continuously provided in the girder direction X.

As shown in FIGS. 3 and 4, the balcony B and the passage C have a handrail wall 80 having a height dimension of about 1 m from the floor surface in the height direction Y for the purpose of preventing falling or blindfolding. It is provided along 81. Further, on the balcony B and the passage C, if necessary, a handrail or a blind glass (not shown) is attached above the handrail wall 80.

In the exclusive portion P and the common portion S, as shown in FIG. 5, the lower floor Fd and the upper floor Fu adjacent to each other in the height direction Y are separated by the floor slab 4, and each exclusive portion P and each of them are separated. The unit element of each dwelling unit is composed of the common portion S adjacent to the exclusive portion P.

As the concrete pillar 7, reinforced concrete having a substantially rectangular cross section is used, and if necessary, steel-framed reinforced concrete having a steel pillar such as a single H-shaped steel or a cross H-shaped steel built therein may be used. .. The concrete columns 7 are arranged at the four corners of the unit element of each dwelling unit, so that they are arranged on each of the pair of girder outer peripheral portions 81 on both sides of the building 8 in the beam-to-beam direction Z, and are provided in the exclusive portion P. It is provided in the common area S of the balcony B and the passage C.

As the inter-beam steel beam 5, as shown in FIG. 6A, H-shaped steel having a substantially H-shaped cross section is used. In the inter-beam steel frame beam 5, for example, the member formation h is about 500 mm to 600 mm, the member width w is about 200 mm, the web plate thickness tw is about 9 mm, and the flange plate thickness tf is about 25 mm.

As the girder steel beam 6, as shown in FIG. 6B, H-shaped steel having a substantially H-shaped cross section is used. For the girder steel beam 6, for example, the member formation h is about 1000 mm, the member width w is about 250 mm, the web plate thickness tw is about 19 mm, and the flange plate thickness tf is about 28 mm.

As shown in FIGS. 7 and 8, the inter-beam steel beam 5 and the girder steel beam 6 are arranged below the upper Fu at the lower Fd and the upper Fu adjacent to each other in the height direction Y of the building 8. The girder steel beam 6 is provided above the inter-beam steel beam 5 arranged above the lower floor Fd in a staggered state.

The inter-beam steel frame beams 5 are arranged at the upper part of each floor of the hierarchical structure and are erected on a pair of concrete columns 7 facing the inter-beam direction Z. As shown in FIG. 7, the inter-beam steel beam 5 is provided with inclined steel brace 51 having substantially the same cross-sectional shape and cross-sectional dimension, and the lower and upper ends of the steel brace 51 are on the lower floor Fd. It is attached to the inter-beam steel beam 5 of the upper floor Fu.

The inter-beam steel frame beam 5 is provided so that the entire flange width fits inside the door boundary wall D. For example, finishing materials 3 and the like are installed on both sides in the girder direction X. The inter-beam steel beam 5 is installed on a pair of concrete columns 7 to ensure a predetermined structural strength, and is provided without forming a beam shape by not projecting into the indoor space of the exclusive portion P.

If necessary, the inter-beam steel beam 5 may be provided with an H-shaped steel wall column 52 extending in the height direction Y, as shown in FIG. As the wall column 52, a steel frame column in which a plurality of H-shaped steels are joined is used, and the inter-beam steel frame beam 5 of the lower floor Fd and the inter-beam steel frame beam 5 of the upper floor Fu are connected to each other by the wall column 52.

The wall pillar 52 is provided so as to fit inside the door boundary wall D, and for example, finishing materials 3 and the like are installed on both sides in the girder direction X. The wall pillar 52 is arranged along, for example, the boundary between the exclusive portion P and the common portion S of the balcony B, and the boundary between the exclusive portion P and the common portion S of the passage C. The wall column 52 may be used by joining a plurality of H-shaped steels, or may use only a single H-shaped steel, or may be formed in a substantially rectangular cross section or a substantially square cross section.

In the wall pillar 52, for example, the steel pillar of H-shaped steel on the lower floor Fd and the steel pillar of H-shaped steel on the upper floor Fu are joined by high-strength bolt friction or welding for each of the second to third floors. It is joined with. Since the wall pillar 52 improves the horizontal strength of the building 8, the dimension of the inter-beam steel beam 5 is reduced in one or both of the balcony B and the passage C, or the inter-beam steel beam 5 is installed. Can be omitted.

The girder steel beam 6 is arranged at the lower part of each floor of the hierarchical structure and is erected on a pair of concrete columns 7 facing the girder direction X. The girder steel beam 6 is not provided in each exclusive portion P, but is provided in the common portion S of the balcony B and the passage C, and each of the pair of girder outer peripheral portions 81 on both sides of the building 8 in the beam-to-beam direction Z. It is placed along.

The girder steel beam 6 is provided with punching metal or finishing material 3 or the like on both sides in the beam-to-beam direction Z, if necessary, inside the handrail wall 80 on the balcony B side and inside the handrail wall 80 on the passage C side. It is provided so that the entire flange width can be accommodated.

As shown in FIG. 9, the inter-beam steel beam 5 and the girder steel beam 6 are each joined to the concrete column 7. The inter-beam steel beam 5 and the girder steel beam 6 are joined to the concrete column 7, and the inter-beam steel beam 5 arranged above the lower floor Fd and the girder steel beam 6 arranged below the upper floor Fu However, they are joined in different steps by bolt joining, high-strength bolt friction joining, welding joining, or the like.

As shown in FIG. 10, the fireproof structure 1 to which the present invention is applied includes a steel frame material 2 provided as a structural material such as a beam material or a pillar material, and a finishing material 3 provided apart from the steel frame material 2.

As shown in FIGS. 11 and 12, the steel frame material 2 is provided as a beam material such as the inter-beam steel frame beam 5 shown in FIGS. 7 and 8, as well as an oblique member such as the steel frame brace 51 shown in FIG. It is provided as a pillar material such as the wall pillar 52 shown in 8, and is mainly provided so as to fit inside the door boundary wall D.

The steel frame material 2 is mainly made of H-shaped steel having a substantially H-shaped cross section, and has a pair of flanges 20 and a web 23 erected on the pair of flanges 20. As shown in FIG. 6A, the steel frame material 2 has a substantially H-shaped cross section in which the member width w at each flange 20 is smaller than that of the member h in which the pair of flanges 20 are separated from each other. It is desirable that the narrow H-section steel of the above is used.

As shown in FIG. 11A, when the steel frame material 2 is provided as a beam material such as an inter-beam steel frame beam 5, the upper flange 21 on the upper side and the lower flange 22 on the lower side are formed in the height direction Y. As a pair, the web 23 is erected from the lower flange 22 to the upper flange 21 extending in the height direction Y.

As shown in FIG. 11B, when the steel frame material 2 is provided as a column material such as a wall column 52, the upper flange 21 on one side and the lower flange 22 on the other side are paired in the beam-to-beam direction Z. Then, the web 23 is erected so as to extend from the lower flange 22 to the upper flange 21 in the inter-column direction Z.

As the steel frame material 2, one narrow H-shaped steel or the like is used alone, and as shown in FIG. 12A, a plurality of narrow H-shaped steels or the like are bolted or frictionally joined to each other by flanges 20. Alternatively, a plurality of narrow H-shaped steels or the like connected to each other by being joined by welding or the like may be used.

In the steel frame material 2, a pair of finishing materials 3 are installed on both side surfaces of the door boundary wall D only on both sides in the girder direction X, so that finishing materials 3 are installed on both sides in the beam-to-beam direction Z. It is provided so as to fit inside the door boundary wall D without any problem. The steel frame material 2 is not limited to this, and as shown in FIG. 12B, finishing materials 3 may be installed on both sides of the girder direction X and the beam-to-beam direction Z.

When the steel frame material 2 is provided so as to fit inside the door boundary wall D or the like, the strong axis α or the weak axis β of the narrow H-shaped steel or the like is shown in FIG. 13 in the cross-sectional direction of the steel frame material 2. It is desirable that a pair of finishing materials 3 on both side surfaces of the door boundary wall D are arranged substantially orthogonal to each other.

As shown in FIG. 13A, the steel frame material 2 is sandwiched between a pair of finishing materials 3 with the flanges 20 and the finishing material 3 arranged on the sides of the steel frame material 2 in a direction substantially orthogonal to each other. Is provided. At this time, in the steel frame material 2, the strong shaft α such as narrow H-shaped steel and the finishing material 3 are arranged substantially orthogonal to each other.

As shown in FIG. 13B, the steel frame material 2 is provided so that each flange 20 and the finishing material 3 are arranged so as to be substantially parallel to each other and sandwiched between the pair of finishing materials 3. At this time, in the steel frame material 2, the weak axis β such as narrow H-shaped steel and the finishing material 3 are arranged substantially orthogonal to each other.

The steel aggregate 2 is in a state where the fireproof coating is not applied (cover thickness of rock wool or the like 0 mm) without the rock wool or glass wool being wrapped or sprayed around the outer periphery of the narrow H-shaped steel or the like to be the steel aggregate 2. ). In addition, although the steel frame 2 is in a state where the fireproof coating is not applied to the outer periphery of the narrow H-shaped steel or the like which is the steel frame 2, insulation such as glass wool is provided only for the purpose of improving the sound insulation performance. May be good.

The finishing material 3 is a gypsum board, a rock wool board, a calcium silicate board, an ALC board (a lightweight cellular concrete board cured by high temperature and high pressure steam) or a GRC board (a cement mortar and glass fiber) formed in a substantially flat plate shape or the like. A fireproof plate that exhibits a predetermined heat insulating performance such as a composite plate) is used. In the finishing material 3, a single type of refractory plate may be used as a plurality of layers, or a plurality of types of refractory plates may be used as a plurality of layers. The finishing material 3 is provided so as to be separated from the steel frame material 2 in the girder direction X or the like in the cross-sectional direction of the steel frame material 2.

The finishing materials 3 are provided in pairs on both side surfaces of the door boundary wall D, and the pair of finishing materials 3 are provided as a part of the door boundary wall D. The door boundary wall D is provided with a steel frame material 2 sandwiched between a pair of finishing materials 3, and the steel frame material 2 is provided so as to fit inside the door boundary wall D in which the pair of finishing materials 3 are separated from each other.

As shown in FIGS. 11 to 13, an approach gap 30 is formed between the finishing material 3 and the steel frame material 2 at a position where the finishing material 3 is closest to the steel frame material 2 and separated from the steel frame material 2. To. Further, the finishing material 3 is separated from the steel frame material 2 at a position other than the approaching gap portion 30 to form a hollow gap portion 31.

In any of the cases shown in FIGS. 11 to 13, there is an approach gap 30 formed between the finishing material 3 and the steel frame material 2 so as to be separated from the steel frame material 2 as shown in FIG. 14 (a). In addition, an air layer G is formed with a predetermined layer thickness d. The layer thickness d of the air layer G in the approach gap 30 is, for example, about 0 mm or more and 50 mm or less. Further, the air layer G is also formed in the hollow gap portion 31 formed by separating the finishing material 3 from the steel frame material 2 at a position other than the approach gap portion 30.

As shown in FIG. 13A, when the finishing material 3 is arranged in a direction substantially orthogonal to the flange 20 of the steel frame material 2, the side end portion 20a of the flange 20 is arranged at the closest position. The gap formed by separating the side end portion 20a of the flange 20 and the finishing material 3 is the approach gap portion 30. Then, in the finishing material 3, a hollow gap portion 31 having a space larger than that of the approach gap portion 30 is formed on one side or both sides of the flange 20 on the outer surface 20b side.

As shown in FIG. 13B, when the finishing material 3 is arranged so as to be substantially parallel to the flange 20 of the steel frame material 2, the outer surface 20b of the flange 20 is arranged at the position closest to the flange. The gap formed so that the outer surface 20b of 20 and the finishing material 3 are separated from each other becomes the approach gap portion 30. Then, in the finishing material 3, a hollow gap portion 31 having a space larger than that of the approach gap portion 30 is formed on one side or both sides of the flange 20 on the side end portion 20a side.

As shown in FIG. 14A, the refractory structure 1 to which the present invention is applied utilizes the heat insulating performance of the finishing material 3 serving as the door boundary wall D and the like, and is formed by the air layer G formed in the approach gap 30. By suppressing heat transfer from the finishing material 3 to the steel frame material 2, the fire resistance performance of the steel frame material 2 is improved. Therefore, in the fireproof structure 1 to which the present invention is applied, an air layer G for reducing heat conduction is formed particularly in the approaching gap 30 on one side surface or both side surfaces heated in the event of a fire in the door boundary wall D. Will be done.

Here, in the conventional steel structure 9, as shown in FIG. 14B, a fireproof coating material 90 such as rock wool is filled between the column or beam serving as the structural frame 91 and the finishing surface material 92. Therefore, the air layer G is not formed between the structural skeleton 91 and the finishing face material 92. On the other hand, in the fireproof structure 1 to which the present invention is applied, as shown in FIG. 14A, the approach gap portion 30 formed at the position closest to the steel frame material 2 and separated from the steel frame material 2 is formed. The air layer G is formed without providing the fireproof coating material 90 such as rock wool. At this time, the fireproof structure 1 to which the present invention is applied can suppress heat transfer from the finishing material 3 to the steel frame material 2 by the heat insulating effect of the air layer G formed in the approach gap portion 30.

In FIG. 15, in order to verify the heat insulating effect of the air layer G formed in the approaching gap 30, the doorway wall D that receives fire heating is provided by using the peak fire in the fire chamber FR of the exclusive portion P as a fire external force. A target heat conduction analysis was carried out to evaluate the temperature of the steel frame material 2 provided inside the door boundary wall D.

In this heat conduction analysis, the member formation h of the steel frame material 2 shown in FIG. 6A is 400 mm, the member width w is 200 mm, the web plate thickness tw is 8 mm, and the flange plate thickness tf is 13 mm, and the gypsum used as the finishing material 3 is used. The plate thickness t of the board was 12.5 mm. Further, in this heat conduction analysis, it is assumed that the air layer G is also formed in the hollow gap portion 31 formed at a position other than the approach gap portion 30.

In this heat conduction analysis, as shown in FIG. 15A, the conventional steel structure 9 is defined as a structure in which the structural skeleton 91 and the finishing surface material 92 are in contact with each other and the air layer G is not formed. Further, in the fireproof structure 1 to which the present invention is applied, as shown in FIG. 15 (b), when the weak axis β of the steel frame material 2 and the finishing material 3 are arranged substantially orthogonally, and in FIG. 15 (c). ), The case where the strong axis α of the steel frame material 2 and the finishing material 3 are arranged substantially orthogonally is compared with the conventional steel frame structure 9.

In this heat conduction analysis, as shown in FIGS. 15 (b) and 15 (c), the layer thickness d of the air layer G formed in the approach gap 30 between the finishing material 3 and the steel frame material 2 was set to 25 mm. .. As for the heating conditions, one side surface of the doorway wall D to be heated at the time of fire was heated for 30 minutes according to the ISO834 standard heating curve, and the other side surface was in contact with air at room temperature. For the thermophysical property values of each material in this heat conduction analysis, the values listed in the Eurocode and AIJ fire resistance design guidelines were adopted.

In this heat conduction analysis, the result of analyzing the temperature history at the side end portion 20a of the flange 20 on one side surface of the door boundary wall D heated at the time of fire is shown in FIG. Here, the case where the structural skeleton 91 shown in FIG. 15A and the finishing surface material 92 are in contact with each other and the air layer G is not formed is defined as the prior art. Further, the case where the weak axis β of the steel frame material 2 shown in FIG. 15 (b) and the finishing material 3 are arranged substantially orthogonal to each other is regarded as the weak axis orthogonal to the steel frame material 2 shown in FIG. 15 (c). The case where the strong axis α and the finishing material 3 are arranged substantially orthogonally is defined as the strong axis orthogonality of the present invention. In addition, in FIG. 16, the case of the conventional steel frame structure 9 filled with the fireproof coating material 90 shown in FIG. 14B is regarded as having the fireproof coating material.

As shown in FIG. 16, in the fireproof structure 1 to which the present invention is applied, the temperature of the side end portion 20a of the flange 20 30 minutes after the start of heating is 50 ° C. orthogonal to the weak axis of the present invention, as compared with the prior art. It can be seen that the temperature is reduced by about 30 ° C. at the strong axis orthogonal to the present invention. From this, the fireproof structure 1 to which the present invention is applied has a side end portion 20a of the flange 20 30 minutes after the start of heating in both the weak axis orthogonality and the strong axis orthogonality of the present invention as compared with the prior art. It can be seen that the air layer G in the approaching gap 30 exerts a heat insulating effect because the temperature is reduced.

At this time, the fireproof structure 1 to which the present invention is applied exerts a heat insulating effect on the air layer G of the approaching gap 30 while utilizing the heat insulating performance of the finishing material 3 such as gypsum board, and the steel frame material from the finishing material 3 is exhibited. By suppressing the heat transfer to 2, it is possible to delay the temperature rise of the steel frame material 2. Further, in the refractory structure 1 to which the present invention is applied, since the refractory coating material 90 is not provided on the steel frame material 2, the material cost of the refractory coating material 90 can be reduced, and the steel frame material 2 has a complicated shape. It is possible to shorten the construction period by reducing the construction labor by eliminating the need for the construction of the fireproof coating material 90.

As a result, in the fireproof structure 1 to which the present invention is applied, since the steel frame material 2 is not provided with the fireproof coating material 90 such as rock wool, the material cost and the construction cost of the fireproof coating material 90 are suppressed, and at the same time, the finish is finished. By forming the air layer G in the approaching gap 30 that separates the material 3 and the steel frame material 2, the temperature rise of the steel frame material 2 is delayed in the event of a fire, and the material becomes a structural material such as a beam material or a pillar material. It is possible to sufficiently improve the fire resistance performance of the steel frame material 2.

Further, in the fireproof structure 1 to which the present invention is applied, the temperature of the steel frame material 2 30 minutes after the start of heating becomes higher than that in the case where the fireproof coating material 90 is filled with the conventional steel frame structure 9. However, according to the fireproof performance test / evaluation work method manual (Japan Building Research Institute), in general wall structures, the temperature 30 minutes after the start of heating should be below 400 ° C. It can be seen that even in the refractory structure 1 to which the present invention is applied, the temperature rise of the steel frame material 2 is sufficiently delayed. At this time, the refractory structure 1 to which the present invention is applied is filled with the refractory coating material 90 shown in FIG. 14B because the temperature 30 minutes after the start of heating falls below 400 ° C. and exhibits sufficient refractory performance. It can be seen that the conventional steel structure 9 (with a fireproof coating material) has an excessive fireproof performance as compared with the fireproof structure 1 to which the present invention is applied as shown in FIG. 14A.

In the fireproof structure 1 to which the present invention is applied, since the air layer G is formed in the approaching gap 30 between the finishing material 3 and the steel frame material 2 without providing the fireproof coating material 90, the finishing material 3 is used. Vibration propagation to the steel frame material 2 is suppressed, and it is possible to improve the sound insulation performance on the door boundary wall D or the like. Further, in the fireproof structure 1 to which the present invention is applied, a steel frame that becomes a structural material such as a beam material or a pillar material by forming an air layer G in an approaching gap 30 between the finishing material 3 and the steel frame material 2. The finishing material 3 can be easily installed on one side or both sides of the steel frame material 2 regardless of the construction error of the material 2.

In the fireproof structure 1 to which the present invention is applied, a narrow H-shaped steel is used as the steel frame material 2, and as shown in FIG. 13A, the flange 20 of the steel frame material 2 and the finishing material 3 are attached to each other. It is desirable that they are arranged in substantially orthogonal directions. At this time, the fire-resistant structure 1 to which the present invention is applied has the fire-resistant performance of the steel frame material 2 even when the steel frame material 2 is provided so as to be sandwiched between the pair of finishing materials 3 and fit inside the door boundary wall D. At the same time, it is possible to provide a thin-walled door boundary wall D without forming a beam type or a pillar type by the steel frame material 2.

Further, in the fireproof structure 1 to which the present invention is applied, as shown in FIG. 13, the steel frame material 2 is sandwiched between the pair of finishing materials 3 as the door boundary wall D, so that the outer surface 20b side of the flange 20 of the steel frame material 2 or A hollow gap portion 31 having a space larger than that of the approach gap portion 30 is formed on the side end portion 20a side. At this time, in the fireproof structure 1 to which the present invention is applied, even if the thin wall door boundary wall D is provided and the air layer G of the approaching gap 30 becomes smaller, the hollow gap at a position other than the approaching gap 30 The air layer G of the portion 31 becomes large, and the air layer G of the hollow gap portion 31 exerts a sufficient heat insulating effect, and the heat is transmitted from one side surface to the other side surface which is heated in the event of a fire in the door boundary wall D. It is possible to suppress heat.

Although the examples of the embodiments of the present invention have been described in detail above, the above-described embodiments are merely examples of the embodiment of the present invention, and the technical aspects of the present invention are based on these. The scope should not be construed in a limited way.

1: Fireproof structure 2: Steel frame 20: Flange 20a: Side end 20b: Outer surface 21: Upper flange 22: Lower flange 23: Web 3: Finishing material 30: Approaching gap 31: Hollow gap 4: Floor slab 5: Inter-beam steel beam 51: Steel brace 52: Wall column 6: Girder steel beam 7: Concrete column 8: Building 80: Handrail wall 81: Girder outer circumference 82: Inter-beam outer periphery A: Opening B: Balcony C: Passage D: Door boundary wall E: Entrance FR: Fire chamber Fd: Lower floor Fu: Upper floor G: Air layer P: Exclusive part S: Common part X: Girder direction Y: Height direction Z: Beam-to-beam direction α: Strong axis β: Weak axis

Claims (4)

It is a fireproof structure provided in the structural material of a building.
A steel frame material provided as a structural material such as a beam material or a column material and a finishing material provided apart from the steel frame material are provided.
A fireproof coating material is not provided between the finishing material and the steel frame material in an approaching gap formed by separating the finishing material from the steel frame material at a position closest to the steel frame material. ,
The finishing material is provided as a pair on both side surfaces of the door boundary wall as a part of the door boundary wall separating the exclusive portion of the building.
The door boundary wall is sandwiched between the pair of finishing materials to provide the steel frame material, and a hollow gap portion having a space larger than the approach gap portion is formed, and a piece to be heated in the event of a fire in the door boundary wall. A fire-resistant structure characterized in that an air layer is formed in the approaching gap on a side surface or both side surfaces and the hollow gap communicating with the approaching gap. As the steel frame material, an H-shaped steel having a pair of flanges and a web erected on the pair of flanges is used, and the direction in which the flange and the finishing material are substantially orthogonal to each other on the side of the steel frame material. The fireproof structure according to claim 1 , wherein the fireproof structure is provided so as to be sandwiched between a pair of the finishing materials. The steel frame material has a pair of flanges and a web erected on the pair of flanges, and the member width at each of the flanges is smaller than that of a member having the pair of flanges separated from each other. The fireproof structure according to claim 1 or 2, wherein a narrow H-shaped steel is used. The fireproof structure according to any one of claims 1 to 3 , wherein a fireproof plate such as gypsum board, rock wool board, calcium silicate board, ALC board or GRC board is used as the finishing material.

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