JP7565904B2 - Fireproof coating structure for steel members - Google Patents

Description

The present invention relates to a fire-resistant coating structure for steel frame members.

Multiple wooden members surrounding a steel frame member are known (see, for example, Patent Documents 1 to 3).

In Patent Document 1, wood material is laminated onto the surface of a fire-resistant coating material that covers a steel frame member.

JP 2017-008640 A JP 2019-056202 A JP 2019-206854 A

However, corners where the ends of adjacent wooden pieces butt together are heated from two directions during a fire, so compared to other parts, the temperature rises more easily and the joints are more likely to open up. This can lead to a decrease in the fire resistance of steel members.

Taking the above facts into consideration, the present invention aims to prevent the deterioration of the fire resistance of steel frame components.

The fire-resistant coating structure for a steel frame member in the first aspect comprises a steel frame member, a plurality of wood fire-resistant coating materials arranged around the steel frame member to provide fire-resistant coating for the steel frame member, and a corner base material that is bent along the corner where the ends of adjacent wood fire-resistant coating materials abut and has a pair of flange portions to which the ends are respectively attached, and supports the adjacent wood fire-resistant coating materials.

According to the fireproof covering structure for steel frame members of the first aspect , a plurality of wood fireproof covering materials are arranged around the steel frame members. The steel frame members are fireproof covered by these wood fireproof covering materials. As a result, the present invention increases the amount of carbon stored compared to a case where the steel frame members are fireproof covered by gypsum boards, calcium silicate boards, or the like. This contributes to decarbonization.

In addition, adjacent wood fire-resistant covering materials are supported by corner underlayment. The corner underlayment has a pair of flanges that are bent along the corner where the ends of adjacent wood fire-resistant covering materials butt against each other, and the ends of adjacent wood fire-resistant covering materials are attached to the pair of flanges.

This prevents the joints between the ends of adjacent wood fire-resistant covering materials from opening during a fire. Even if the joints between the ends of adjacent wood fire-resistant covering materials do open during a fire, the pair of flanges bent along the corners will block heat from entering the joints into the steel frame members. This improves the fire resistance of the steel frame members.

In this way, the present invention can improve the fire resistance of steel components while contributing to decarbonization.

The second aspect of the fire-resistant coating structure for a steel frame member is the same as the first aspect of the fire-resistant coating structure for a steel frame member, and the corner base material has a second bracket that is bolted to the first bracket while being stacked in the material axial direction of the steel frame member, and one of the bolt holes of the first bracket and the second bracket is a long hole extending in the width direction of the wood fire-resistant coating material, and the other of the bolt holes of the first bracket and the second bracket is a long hole extending in the thickness direction of the wood fire-resistant coating material.

According to the second aspect of the fire-resistant coating structure for a steel member, the first bracket protrudes outward from the steel member. The corner base material has a second bracket. The second bracket is bolted to the first bracket in a state where the second bracket is overlapped with the first bracket in the material axis direction of the steel member.

By attaching the corner base material to the steel frame member via the first bracket and second bracket in this way, the workability of the corner base material is improved.

In addition, one of the bolt holes of the first bracket and the second bracket is an elongated hole extending in the width direction of the wood fire-resistant covering material, and the other of the bolt holes of the first bracket and the second bracket is an elongated hole extending in the thickness direction of the wood fire-resistant covering material.

This allows the corner base material's mounting position to be adjusted in two directions relative to the steel frame member. This makes it possible to absorb processing errors and construction errors in the wood fire-resistant covering material.

The fire-resistant coating structure for steel frame members of the third aspect is the fire-resistant coating structure for steel frame members of the first aspect , in which the corner base material is positioned at a distance from the steel frame members and is supported by the main structure surrounding the steel frame members.

According to the third aspect of the fire-resistant covering structure for steel frame members, the corner base material is disposed at a distance from the steel frame members and is supported by the surrounding framework of the steel frame members. This allows the corner base material and the wood fire-resistant covering material to be installed without being affected by the installation accuracy of the steel frame members.

As explained above, the present invention can prevent the deterioration of the fire resistance of steel frame members.

FIG. 2 is a plan cross-sectional view showing a concrete-filled steel pipe column to which a fire-resistant coating structure for a steel member according to the first embodiment is applied. 2 is an exploded cross-sectional plan view of the corner base material, metal plate, wood fire-resistant covering material, and decorative material shown in FIG. 1 . FIG. FIG. 11 is a cross-sectional plan view showing a concrete-filled steel pipe column to which a fire-resistant coating structure for a steel member according to a second embodiment is applied. A cross-sectional plan view showing a steel column to which a modified example of a fire-resistant coating structure for a steel member according to the second embodiment is applied. FIG. 5 is a cross-sectional plan view showing the base of the steel column shown in FIG. 4 . This is a cross-sectional view taken along line 6-6 in Figure 5. FIG. 5 is an elevation view (side view) showing the column capital part of the steel column shown in FIG. 4 . This is a cross-sectional view taken along line 8-8 in Figure 7. FIG. 2 is a cross-sectional plan view corresponding to FIG. 1 , showing a concrete-filled steel pipe column to which a modified example of the fire-resistant coating structure of the steel member according to the first embodiment is applied. FIG. 10 is an exploded cross-sectional plan view of the corner base material, metal plate, wood fire-resistant covering material, and decorative material shown in FIG. 9 . 1 is a cross-sectional view showing a steel beam to which a modified example of the fire-resistant coating structure of the steel member according to the first embodiment is applied. FIG.

First Embodiment
First, a first embodiment will be described. Note that the arrow X direction and the arrow Y direction shown appropriately in each drawing indicate two horizontal directions perpendicular to each other.

Figure 1 shows a concrete-filled steel pipe column (hereinafter referred to as a "CFT column") 10 to which the fire-resistant structure of the steel member according to this embodiment is applied. The CFT column 10 comprises a steel pipe 12 and concrete 14 filled inside the steel pipe 12.

As an example, the steel pipe 12 is a square steel pipe. This steel pipe 12 is fire-resistant coated with a plurality of wood-based fire-resistant coating materials 30. Note that the steel pipe 12 is not limited to a square steel pipe, and may be a round steel pipe. Also, the steel pipe 12 is an example of a steel frame member.

(First bracket)
2, a pair of first brackets 20 for attaching a corner base material 40 described later is attached to each corner of the steel pipe 12. The pair of first brackets 20 are formed from metal plates such as steel plates, and are arranged with the thickness direction being the material axis direction of the steel pipe 12. In addition, the pair of first brackets 20 are formed into a rectangular shape when viewed from the material axis direction of the steel pipe 12.

The pair of first brackets 20 are arranged along the outer surface (side surface) of each corner of the steel pipe 12. In other words, the pair of first brackets 20 are arranged along directions that intersect with each other (approximately perpendicular in this embodiment) when viewed from the material axis direction of the steel pipe 12. One end of each first bracket 20 is joined by welding or the like while abutting against the outer surface of the steel pipe 12.

Each first bracket 20 is formed with a plurality of first bolt holes 22. The plurality of first bolt holes 22 are through holes that penetrate the first bracket 20 in the thickness direction. The plurality of first bolt holes 22 are also elongated holes that extend in the thickness direction (arrow X direction) of one of the wood fire-resistant coating materials 30A described below. A corner base material 40 described below is attached to this first bracket 20.

(Wood fireproof coating material)
1, a plurality of (four in this embodiment) wood fire-resistant covering materials 30 are arranged to surround the steel pipe 12. More specifically, the plurality of wood fire-resistant covering materials 30 are arranged in a rectangular frame shape surrounding the steel pipe 12 when viewed from the material axis direction of the steel pipe 12, and provide fire-resistant covering for the steel pipe 12.

Each wood fire-resistant coating material 30 is arranged with a gap G between it and the outer surface of the steel pipe 12. The gap G functions as an insulating layer (insulating space). In addition, by leaving a gap G between the outer surface of the steel pipe 12 and the wood fire-resistant coating material 30, interference between the wood fire-resistant coating material 30 and irregularities such as weld beads formed on the outer surface of the steel pipe 12 is suppressed, and the gap G makes it possible to absorb construction errors of the wood fire-resistant coating material 30.

Each wood fire-resistant coating material 30 is formed from a wood board such as CLT (Cross Laminated Timber), LVL (Laminated Veneer Lumber), laminated timber, or plywood. Note that the adhesive used for laminated timber is preferably a thermosetting resin adhesive from the standpoint of fire resistance.

The wood fire-resistant coating material 30 functions as a fire-resistant coating material. Specifically, the wood fire-resistant coating material 30 functions as a substitute layer that provides fire-resistant coating for the steel pipe 12. The substitute layer burns during a fire and forms a carbonized layer (thermal insulation layer), which prevents the heat of the fire from penetrating into the steel pipe 12.

The thickness (thickness) t of the wood fire-resistant coating material 30 is set appropriately according to the required fire resistance performance. More specifically, when wood (wooden material) is heated on one side, it is carbonized to 40mm to 60mm after one hour of heating, 70mm to 90mm after two hours of heating, and 100mm to 120mm after three hours of heating. When wood (wooden material) is heated on two sides, a 10% to 20% margin in the thickness is required, and the wood thickness of pillars, beams, etc. (thickness t of wood fire-resistant coating material 30) is set to 44mm to 72mm after one hour of heating, 77mm to 108mm after two hours of heating, and 110mm to 144mm after three hours of heating.

Examples of tree species (wood) used for the wood fire-resistant covering material 30 include larch, Douglas fir, and cedar. Depending on the tree species, the burning state of the outer surface (front surface) of the wood fire-resistant covering material 30 after heating may differ. For example, in the case of cedar, burning tends to continue over the entire outer surface of the wood fire-resistant covering material 30.

On the other hand, in the case of larch and Douglas fir, burning continues in parts on the outer surface of the wood-based fire-resistant covering material 30, but the fire tends to stop as a whole. Therefore, larch and Douglas fir are preferred as the tree species (wood) to be used for the wood-based fire-resistant covering material 30.

The steel pipe 12 also has a high thermal conductivity. Therefore, even if combustion continues partially on the outer surface of the wood fire-resistant coating material 30 during a fire, the heat of the fire is diffused throughout the steel pipe 12, suppressing localized temperature increases in the steel pipe 12. Furthermore, the concrete 14 inside the steel pipe 12 has a large heat capacity, further suppressing temperature increases in the steel pipe 12.

Therefore, if larch or Douglas fir is used for the wood fire-resistant coating material 30, the fire resistance of the CFT column 10 is ensured even if partial combustion continues on the outer surface of the wood fire-resistant coating material 30 during a fire.

When viewed from the material axis direction of the steel pipe 12, adjacent wood fire-resistant coating materials 30 are arranged along directions that are approximately perpendicular to each other (the direction of arrow X and the direction of arrow Y). Adjacent wood fire-resistant coating materials 30 are arranged with their ends butted against each other, and a joint 32 is formed between the ends. These wood fire-resistant coating materials 30 are attached to the corner base material 40 via a metal plate 34, which will be described later.

The outer surface of the wood fire-resistant coating material 30 is covered with a decorative material 38. The decorative material 38 is made of, for example, wood or a waterproof material such as resin, and is attached to the outer surface of the wood fire-resistant coating material 30 with screws (not shown). This decorative material 38 enhances the design of the CFT column 10.

For example, when the CFT column 10 is installed outdoors, the decorative material 38 as a weather-resistant layer suppresses corrosion of the wood fire-resistant covering material 30 due to rain, etc., thereby improving the durability of the wood fire-resistant covering material 30. Note that the decorative material 38 can be omitted.

(Corner base material)
The corner base material 40 is disposed around the steel pipe 12 along the material axis direction of the steel pipe 12, and is attached to each corner of the steel pipe 12. The corner base material 40 is formed of a light-gauge steel frame or the like having an L-shaped cross section, and is disposed on the outside of each corner of the steel pipe 12. The corner base material 40 is disposed with the material axis direction of the steel pipe 12 as the longitudinal direction, and extends from the column base to the column head of the steel pipe 12.

The corner base material 40 has a pair of flanges 40A. When viewed from the material axis direction of the steel pipe 12, the pair of flanges 40A are bent along the corners 30C of adjacent wood fire-resistant covering materials 30. The ends of adjacent metal plates 34 and the ends of adjacent wood fire-resistant covering materials 30 are attached to the pair of flanges 40A, respectively.

(Metal plate)
The metal plate 34 serving as the heat insulating layer is made of a steel plate, an iron plate, or the like having high thermal conductivity, and is disposed opposite the outer surface (side surface) of the steel pipe 12. On the outer surface of this metal plate 34, a wood fire-resistant covering material 30 is layered.

The metal plate 34 and wood fire-resistant coating material 30 are arranged across the outer surface of the flange portion 40A of the adjacent corner base material 40, and both ends are attached (fastened together) to the flange portion 40A by a number of screws 36. The multiple screws 36 are arranged at intervals in the longitudinal direction of the flange portion 40A.

In addition, the outer surface of the wood fire-resistant coating material 30 is formed with a countersunk hole 31 for the screw 36. The wood fire-resistant coating material 30 and the metal plate 34 may also be formed as a pre-integrated unit. In this case, the metal plate 34 is, for example, bonded to the inner surface of the wood fire-resistant coating material 30 with an adhesive.

(Second bracket)
2, a pair of second brackets 50 are provided on the corner base material 40. The pair of second brackets 50 are formed from metal plates such as steel plates, and are arranged with the thickness direction being the material axis direction of the steel pipe 12. In addition, the pair of second brackets 50 are formed in a rectangular shape when viewed from the thickness direction of the steel pipe 12.

The pair of second brackets 50 are arranged along the inner surfaces of the pair of flange portions 40A. In other words, the pair of second brackets 50 are arranged along directions (arrow X direction and arrow Y direction) that are approximately perpendicular to each other when viewed from the material axis direction of the steel pipe 12. One end of each second bracket 50 is joined by welding or the like while abutting against the inner surfaces of the pair of flange portions 40A.

Each second bracket 50 has a plurality of second bolt holes 52 formed therein. The second bolt holes 52 are through holes that penetrate the second bracket 50 in the thickness direction. The second bolt holes 52 are elongated holes that extend in the width direction (arrow Y direction) of one of the adjacent wood fire-resistant covering materials 30A, 30B. In other words, the first bolt hole 22 and the second bolt hole 52 are elongated holes that extend in directions (arrow X direction, arrow Y direction) that are approximately perpendicular to each other.

The first bolt hole 22 may be an elongated hole extending in the width direction of one of the adjacent wood fire-resistant covering materials 30A, and the second bolt hole 52 may be an elongated hole extending in the thickness direction of one of the adjacent wood fire-resistant covering materials 30A. Furthermore, the first bolt hole 22 and the second bolt hole 52 are not limited to elongated holes, and at least one of the first bolt hole 22 and the second bolt hole 52 may be a circular hole. Furthermore, the first bolt hole 22 and the second bolt hole 52 are an example of a bolt hole.

The pair of second brackets 50 are bolted to the pair of first brackets 20 provided on the steel pipe 12 in a state where they are stacked in the material axis direction of the steel pipe 12. Specifically, the first bracket 20 and the second bracket 50 are joined by bolts 54 that pass through the first bolt holes 22 and the second bolt holes 52, and nuts (not shown). In this way, the corner base material 40 is attached to each corner of the steel pipe 12.

(Action)
Next, the operation of the first embodiment will be described.

As shown in FIG. 1, in this embodiment, multiple wood fire-resistant coating materials 30 are arranged around the steel pipe 12 of the CFT column 10. The steel pipe 12 is fire-resistant coated with these wood fire-resistant coating materials 30. As a result, in this embodiment, the amount of carbon stored is increased compared to when the steel pipe 12 is fire-resistant coated with gypsum board, calcium silicate board, or the like. This can therefore contribute to decarbonization.

Adjacent wood fire-resistant coating materials 30 are supported by corner underlayment 40. Corner underlayment 40 has a pair of flanges 40A arranged along corner 30C where the ends of adjacent wood fire-resistant coating materials 30 abut. The ends of adjacent wood fire-resistant coating materials 30 are attached to the pair of flanges 40A.

This prevents the joints 32 between the ends of adjacent wood fire-resistant coating materials 30 from opening during a fire. Even if the joints 32 between the ends of adjacent wood fire-resistant coating materials 30 open during a fire, the pair of flanges 40A bent along the corners 30C block the penetration of heat from the joints 32 to the steel pipe 12. This improves the fire resistance of the steel pipe 12.

In this way, this embodiment can improve the fire resistance of the steel pipe 12 of the CFT column 10 while contributing to decarbonization.

As shown in FIG. 2, a pair of first brackets 20 are provided at each corner of the steel pipe 12. The pair of first brackets 20 each protrude outward from the outer surface of the corner of the steel pipe 12. The corner base material 40 also has a pair of second brackets 50. The pair of second brackets 50 are bolted to the pair of first brackets 20 in a state where they are overlapped in the material axis direction of the steel pipe 12.

By attaching the corner base material 40 to the steel pipe 12 in this manner via a pair of first brackets 20 and a pair of second brackets 50, the workability of the corner base material 40 is improved.

The first bolt holes 22 of the pair of first brackets 20 are elongated holes extending in the width direction (arrow X direction) of one of the adjacent wood fire-resistant covering materials 30A. The second bolt holes 52 of the pair of second brackets 50 are elongated holes extending in the thickness direction (arrow Y direction) of one of the adjacent wood fire-resistant covering materials 30A. In other words, the first bolt holes 22 and the second bolt holes 52 are elongated holes extending in directions (arrow X direction, arrow Y direction) that are approximately perpendicular to each other.

This allows the attachment position of the corner base material 40 to be adjusted in two directions (the direction of the arrow X and the direction of the arrow Y) relative to the steel pipe 12. This makes it possible to absorb processing errors and construction errors of the wood fire-resistant coating material 30.

The wood fire-resistant coating material 30 is supported by the corner base material 40 with a gap G between it and the outer surface of the steel pipe 12. This creates an insulating layer (air layer) between the outer surface of the steel pipe 12 and the inner surface of the wood fire-resistant coating material 30, further improving the fire resistance of the steel pipe 12.

Furthermore, by providing a gap G between the outer surface of the steel pipe 12 and the wood fire-resistant coating material 30, interference between the unevenness of the weld beads and the like formed on the outer surface of the steel pipe 12 and the wood fire-resistant coating material 30 is suppressed, and construction errors of the wood fire-resistant coating material 30 are absorbed.

The wood fire-resistant coating material 30 also provides fire-resistant coating to the outer surface of the steel pipe 12 via a metal plate 34 that acts as an insulating layer. As a result, if, for example, a fire occurs and combustion continues partially on the outer surface of the wood fire-resistant coating material 30, the metal plate 34 diffuses the heat of the fire, dispersing it throughout the steel pipe 12. As a result, localized temperature increases in the steel pipe 12 are suppressed. This improves the fire resistance of the CFT column 10.

Second Embodiment
Next, a second embodiment will be described. In the second embodiment, the same reference numerals will be used to designate the same components as those in the first embodiment, and the description thereof will be omitted as appropriate.

Figure 3 shows a CFT column 10 to which the fire-resistant coating structure for steel members according to this embodiment is applied. A number of corner base materials 60, reinforcing base materials 62, and intermediate base materials 70 are arranged around the CFT column 10.

(Corner base material)
The corner base material 60 is formed of studs (lightweight steel frames) with a C-shaped cross section, and is disposed on the outside of each corner of the steel pipe 12. The corner base material 60 is disposed with its longitudinal direction aligned with the material axis of the steel pipe 12, and extends from the base to the head of the steel pipe 12. The cross-sectional shape of this corner base material 60 is a rectangle extending in the width direction of one of the adjacent wood fire-resistant covering materials 30.

The corner base material 60 is arranged along the corner 30C of adjacent wood fire-resistant covering materials 30. This corner base material 60 has a pair of flange portions 60A. When viewed from the material axis direction of the steel pipe 12, the pair of flange portions 60A are bent along the corner 30C of adjacent wood fire-resistant covering materials 30. The ends of adjacent metal plates 34 and the ends of adjacent wood fire-resistant covering materials 30 are attached to the pair of flange portions 60A by a plurality of screws 36. In addition, the corner base material 60 is reinforced by a reinforcing base material 62.

(Reinforcing base material)
The reinforcing base material 62, like the corner base material 60, is formed from a stud (lightweight steel frame) with a C-shaped cross section, and is disposed adjacent to the corner base material 60. The reinforcing base material 62 is disposed in a different orientation (rotated by 90°) from the corner base material 60 when viewed from the material axis direction of the steel pipe 12. The reinforcing base material 62 prevents the corner base material 60 from collapsing. The reinforcing base material 62 can be omitted as appropriate.

(Intermediate base material)
A pair of intermediate base materials 70 are disposed between adjacent corner base materials 60. The pair of intermediate base materials 70 are formed of studs (lightweight steel frames) with a C-shaped cross section, and are disposed back-to-back with each other. The pair of intermediate base materials 70 are disposed with the material axis direction of the steel pipes 12 as the longitudinal direction, and extend from the base portion to the head portion of the steel pipes 12. The cross-sectional shape of the intermediate base material 70 is a rectangle extending in the thickness direction of the wood fire-resistant coating material 30 that the intermediate base material 70 supports.

(Lower runner, upper runner)
The lower ends of the corner base material 60, the reinforcing base material 62, and the intermediate base material 70 are supported by a lower runner 80. The lower runner 80 is formed of a lightweight steel frame or the like with a C-shaped cross section that is open at the top, and a plurality of lower runners 80 are arranged in a rectangular frame shape so as to surround the column base of the steel pipe 12.

Each lower runner 80 is fixed to a structural body such as a slab with screws or the like. The lower ends of the corner base material 60, the reinforcing base material 62, and the intermediate base material 70 are fitted inside these lower runners 80 and fixed with screws or the like (not shown).

Similarly, the upper ends of the corner base material 60, the reinforcing base material 62, and the intermediate base material 70 are supported by upper runners (not shown). The upper runners are formed of light steel frames or the like with a C-shaped cross section that opens downward, and multiple upper runners are arranged in a rectangular frame shape to surround the column heads of the steel pipes 12.

Each upper runner is fixed, for example, with screws to the upper floor's structural members, such as the slabs and beams. The lower ends of the corner base material 60, the reinforcing base material 62, and the intermediate base material 70 are fitted inside these upper runners and fixed with screws. The lower runner 80 and the upper runner are examples of runners.

(Wood fireproof coating material)
The multiple wood fire-resistant coating materials 30 are arranged to surround the steel pipes 12 of the CFT column 10, and are arranged at a distance G from the outer surface of the steel pipes 12. Each wood fire-resistant coating material 30 is arranged across the corner base material 60 and the intermediate base material 70, and both ends of each material are attached to the corner base material 60 and the intermediate base material 70 by multiple screws 36, respectively.

Adjacent wood fire-resistant coating materials 30 are joined by a notch on a pair of intermediate base materials 70. These wood fire-resistant coating materials 30 provide fire protection to the steel pipes 12 of the CFT columns 10.

(Action)
Next, the operation of the second embodiment will be described. Note that the explanation of the same operations and effects as those of the first embodiment will be omitted as appropriate.

As shown in FIG. 3, adjacent wood fire-resistant coating materials 30 are supported by a corner base material 60. The corner base material 60 has a pair of flange portions 60A. The pair of flange portions 60A are bent along the corner portion 30C where the ends of adjacent wood fire-resistant coating materials 30 abut. The ends of adjacent wood fire-resistant coating materials 30 are attached to the pair of flange portions 60A, respectively.

This prevents the joints 32 between the ends of adjacent wood fire-resistant coating materials 30 from opening during a fire. Even if the joints 32 between the ends of adjacent wood fire-resistant coating materials 30 open during a fire, the pair of flanges 60A bent along the corners 30C block the penetration of heat from the joints 32 to the steel pipe 12. This improves the fire resistance of the steel pipe 12.

In this way, in this embodiment, like the first embodiment described above, it is possible to improve the fire resistance of the steel pipe 12 of the CFT column 10 while contributing to decarbonization.

The corner base material 60 is placed at a distance G from the steel pipe 12 and is supported by the surrounding structure of the steel pipe 12 via a lower runner 80 and an upper runner (not shown). This allows the corner base material 60 and wood fire-resistant coating material 30 to be installed without being affected by the installation accuracy of the steel pipe 12.

(Modification of the second embodiment)
In the second embodiment, the corner base material 60 is formed by a stud. However, the corner base material 60 is not limited to a stud. For example, in the modified example shown in Fig. 4 and Fig. 5, the corner base material 90 is formed by a lightweight steel frame having an L-shaped cross section.

The corner base members 90 are arranged on the outside of each corner of the steel pipe 12. The corner base members 90 are arranged with the material axis direction of the steel pipe 12 as the longitudinal direction, and extend from the base to the head of the steel pipe 12.

The corner base material 90 has a pair of flange portions 90A. The pair of flange portions 90A are bent along the corner portions 30C of adjacent wood fire-resistant covering materials 30. The ends of adjacent metal plates 34 and the ends of adjacent wood fire-resistant covering materials 30 are attached to the pair of flange portions 90A.

As shown in Figures 5 and 6, the lower end of the corner base material 90 is supported by a lower runner 92. As shown in Figure 6, the lower runners 92 are formed of light steel frames with an L-shaped cross section, and multiple lower runners 92 are arranged in a rectangular frame shape to surround the column base of the steel pipe 12. Each lower runner 92 is fixed to a structure 94 such as a slab with screws, for example. The lower end of the corner base material 90 is fixed to these lower runners 92 with screws, etc.

As shown in Figures 7 and 8, the upper end of the corner base material 90 is supported by an upper runner 96. The upper runner 96 is formed of a lightweight steel frame with an L-shaped cross section, and is attached to the lower flange portion 100A of the steel beam 100. The upper end of the corner base material 90 is fixed to this upper runner 96 with screws, etc.

As shown in FIG. 7, adjacent corner base materials 90 may be connected via a connecting material 98. The upper runner 96 and the lower runner 92 are examples of runners.

In this way, the shape and support structure of the corner base material 90 can be changed as appropriate.

(Modifications of the first to third embodiments)
Next, modified examples of the first to third embodiments will be described. Note that, although various modified examples will be described below using the first embodiment as an example, these modified examples can also be appropriately applied to the second and third embodiments.

In the first embodiment, the steel frame member is the steel pipe 12 of the CFT column 10. However, the steel frame member is not limited to the steel pipe 12 and may be a shaped steel.

For example, in the modified example shown in Figures 9 and 10, a steel column 110 as a steel member is formed of an H-shaped steel. The steel column 110 has a pair of flange portions 110A, 110B that face each other in the horizontal direction, and a web portion 110C that connects the pair of flange portions 110A, 110B.

A pair of first brackets 20 are attached to both ends of the pair of flanges 110A by welding or the like. A corner base material 40 is attached to the pair of first brackets 20 via a pair of second brackets 50.

In the first embodiment, the steel frame member is a column (CFT column 10). However, the steel frame member is not limited to a column, and may be a steel beam. For example, in the modified example shown in FIG. 11, the steel frame member is a steel beam 120.

The steel beam 120 is formed from an H-shaped steel. This steel beam 120 has an upper flange portion 120A and a lower flange portion 120B that face each other in the vertical direction, and a web portion 120C that connects the upper flange portion 120A and the lower flange portion 120B.

A pair of first brackets 20 are attached to both ends of the lower flange portion 120B by welding or the like. A corner base material 40 is attached to the pair of first brackets 20 via a pair of second brackets 50.

A slab 130 is provided on top of the upper flange portion 120A. A first bracket 20 is attached to each end of both sides of the upper flange portion 120A by welding or the like. A base material 140 is attached to the first bracket 20 via a second bracket 50. The base material 140 is formed of a flat bar or the like. The end of the wood fire-resistant coating material 30 is attached to the base material 140 by a number of screws or the like.

In this way, the steel members are not limited to CFT columns or steel columns, but can also be steel beams.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and one embodiment and various modified examples may be used in appropriate combination, and the present invention may of course be embodied in various forms without departing from the spirit of the present invention.

12 Steel pipes (steel frame members)
20 First bracket 22 First bolt hole (bolt hole)
30 Wood fire-resistant coating material 30C Corner portion 40 Corner base material 40A Flange portion 50 Second bracket 52 Second bolt hole (bolt hole)
60 Corner base material 60A Flange portion 90 Corner base material 90A Flange portion 110 Steel column (steel member)
120 Steel beam (steel member)
G interval

Claims (8)

Steel members;
A plurality of wood fire-resistant covering materials are arranged around the steel frame members and provide fire-resistant covering for the steel frame members;
a corner base material that is bent along the corner where the ends of the adjacent wood fire-resistant covering materials butt against each other and has a pair of flanges to which the ends are respectively attached, and that is attached to the steel frame member and supports the adjacent wood fire-resistant covering materials;
A first bracket protruding outward from the steel frame member and arranged with its thickness direction being in the material axis direction of the steel frame member;
Equipped with
The corner base material has a second bracket that is bolted to the first bracket in a state overlapping the first bracket.
Fire-resistant coated structure for steel components. Steel frame members;
A plurality of wood fire-resistant covering materials are arranged around the steel frame members and provide fire-resistant covering for the steel frame members;
a corner base material that is bent along the corner where the ends of the adjacent wood fire-resistant covering materials butt against each other and has a pair of flanges to which the ends are respectively attached, and that is attached to the steel frame member and supports the adjacent wood fire-resistant covering materials;
A first bracket protruding from the steel frame member;
Equipped with
The corner base material has a second bracket that is bolted to the first bracket in a state where the second bracket is overlapped thereon,
One of the bolt holes of the first bracket and the second bracket is an elongated hole extending in the width direction of the wood fire-resistant covering material, and the other of the bolt holes of the first bracket and the second bracket is an elongated hole extending in the thickness direction of the wood fire-resistant covering material.
Fire-resistant coated structure for steel components. Steel frame members;
A plurality of wood fire-resistant covering materials are arranged around the steel frame members and provide fire-resistant covering for the steel frame members;
a corner base material that supports the adjacent wood fire-resistant covering materials and has a pair of flanges to which the ends of the adjacent wood fire-resistant covering materials are attached, the corner base material being bent along the corner where the ends of the adjacent wood fire-resistant covering materials are butted against each other;
A first bracket protruding outward from the steel frame member;
Equipped with
The corner base material has a second bracket that is bolted to the first bracket in a state where the second bracket is overlapped in the material axis direction of the steel frame member,
One of the bolt holes of the first bracket and the second bracket is an elongated hole extending in the width direction of the wood fire-resistant covering material, and the other of the bolt holes of the first bracket and the second bracket is an elongated hole extending in the thickness direction of the wood fire-resistant covering material.
Fire-resistant coated structure for steel components. A metal plate is attached in advance to the inner surface of the wood fire-resistant covering material,
The wood fire-resistant covering material and the metal plate are attached to the flange portion by screws.
A fire-resistant coating structure for a steel frame member according to any one of claims 1 to 3. The metal plates of adjacent wood fire-resistant covering materials are not integrated with each other.
A fire-resistant coating structure for a steel frame member according to claim 4. The steel frame member is a steel pipe or a steel pipe filled with concrete, which constitutes a column.
A fire-resistant coating structure for a steel frame member according to any one of claims 1 to 5. The corner base material is formed to have an L-shaped cross section along the corner portion.
A fire-resistant coating structure for a steel frame member according to any one of claims 1 to 6. A decorative material is provided to cover the outer surface of the wood fire-resistant covering material.
A fire-resistant coating structure for a steel frame member according to any one of claims 1 to 7.