Fire-resistant coating structure and construction method of the same

Abstract

To provide a fire-resistant coating structure for joints of steel frame members with excellent workability and its construction method.SOLUTION: Provided is a fire-resistant coating structure 10 at a joint 14 where the ends of steel frame member 20 protruding from a wooden-steel member 12 are joined, the wooden-steel member 12 including the steel frame member 20 and a wood fire-resistant coating material 22 made of a wood material that provides a fire-resistant coating on the surface of the steel frame member 20, and the fire-resistant coating structure 10 includes a non-combustible material 16 provided on an end surface 42 of the wood fire-resistant coating material 22 on the joint 14 side, and a plate-shaped dry fire-resistant coating material 18 provided around the joint 14 so as to seal the gap between the wood fire-resistant coating materials 22 of the wooden-steel members 12 located on both sides of the joint 14.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a fire-resistant coating structure for joints of steel frame members provided with a fire-resistant coating material made of wood, and a construction method thereof. [Background technology]

[0002] It has been known that wood, a renewable resource with the effect of fixing carbon dioxide, is used as a fire-resistant covering material for steel beams in order to reduce the environmental impact in the construction industry (see, for example, Patent Document 1). Hereinafter, fire-resistant covering materials made of wood will be referred to as wood covering materials, and steel beams equipped with wood covering materials will be referred to as wood-steel beams.

[0003] In the event of a fire, the carbonized layer formed by the burning wood covering of the wooden beams blocks the heat of the fire, keeping the temperature of the steel frame below the carbonization temperature.After the fire ends, the burning of the wood covering material will self-extinguish, ensuring fire resistance.

[0004] Wood cladding is usually installed in a factory, but for the joints between wood and steel beams, the steel frames are bolted together on-site, so the wood cladding is not installed in a factory and a separate fire-resistant coating is applied after the steel frames are joined. In this case, the fire-resistant coating must be applied so that the temperature of the steel frame in the event of a fire will be below the carbonization temperature of the wood, so as not to impair the fire resistance performance of the wood and steel beams.

[0005] Conventional fire-resistant coating methods for joints between steel frame members and wooden members include, for example, a method of covering the joint with wood such as laminated lumber (see, for example, Non-Patent Document 1) and a method of covering the joint with a sprayed fire-resistant coating material such as sprayed rock wool (see, for example, Non-Patent Document 1 and Patent Document 2). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2023-99880 [Patent Document 2] Japanese Patent Application Publication No. 2019-218851 [Non-patent literature]

[0007] [Non-Patent Document 1] Japan Laminated Timber Industry Association website, "Fitment of main structural components of wood hybrid fireproof buildings," [online], [Retrieved April 26, 2024], Internet<URL:https: / / www.syuseizai.com / data02> ,<https: / / www.syuseizai.com / jlwa / wp-content / uploads / 2016 / 04 / mokusituosamari.pdf> Summary of the Invention [Problem to be solved by the invention]

[0008] In the above-mentioned wood covering method, the wood covering material needs to be processed to fit the shape of the bolt at the joint, but this processing is very difficult and not practical.

[0009] Furthermore, the method of covering with the above-mentioned spray-on fireproof coating requires the surrounding area to be cured and the thickness of the coating to be managed during construction. Also, if the joints are to be finished with decorative wood to match the design of the wood-steel beams, the decorative wood cannot be directly attached to the spray-on fireproof coating, so in places where the joints are long, a fastening base for the decorative wood must be installed. For these reasons, the method using spray-on fireproof coating requires a lot of work during construction and is difficult to install.

[0010] The present invention has been made in view of the above, and aims to provide a fire-resistant coating structure for joints of steel frame members that is easy to install and a method for installing the same. [Means for solving the problem]

[0011] In order to solve the above-mentioned problems and achieve the object, the fire-resistant coating structure of the present invention is a fire-resistant coating structure at a joint where the ends of steel frame members protruding from wooden-steel members are joined, the fire-resistant coating structure comprising steel frame members and a wood fire-resistant coating material made of a wood material that provides fire-resistant coating to the surface of the steel frame members, and is characterized by having a non-combustible material provided on the end surface of the wood fire-resistant coating material on the joint side, and a plate-shaped dry fire-resistant coating material provided around the joint so as to seal the gap between the wood fire-resistant coating materials of the wooden-steel members located on both sides of the joint.

[0012] Another fire-resistant covering structure according to the present invention is characterized in that, in the above-mentioned invention, the dry fire-resistant covering material is a fiber-mixed calcium silicate board.

[0013] Another fire-resistant covering structure according to the present invention is characterized in that, in the above-mentioned invention, decorative wood is provided on the outside of the dry fire-resistant covering material.

[0014] Another fire-resistant coating structure according to the present invention is characterized in that, in the above-mentioned invention, an inorganic filler is provided in the gap between the wood fire-resistant coating material and the dry fire-resistant coating material.

[0015] Another fire-resistant coating structure according to the present invention is characterized in that, in the above-mentioned invention, the thickness of the dry fire-resistant coating material is set to a thickness that is equal to or greater than the maximum temperature of the steel frame member at the joint when heated by fire, which is below the carbonization temperature.

[0016] In addition, the method for constructing a fire-resistant coated structure according to the present invention is a method for constructing the above-mentioned fire-resistant coated structure, and is characterized by comprising the steps of joining the ends of the steel frame members to form the joint, providing the non-combustible material on the end surface of the wood fire-resistant coating material on the joint side, and providing the dry fire-resistant coating material around the joint. [Effects of the Invention]

[0017] The fire-resistant coating structure of the present invention is a fire-resistant coating structure at a joint where the ends of steel frame members protruding from wooden and steel members are joined, the fire-resistant coating structure comprising steel frame members and a wood fire-resistant coating material made of a wood material that provides fire-resistant coating to the surface of the steel frame members, and the fire-resistant coating structure comprises a non-combustible material provided on the end surface of the wood fire-resistant coating material on the joint side, and a plate-shaped dry fire-resistant coating material provided around the joint so as to seal the gap between the wood fire-resistant coating materials of the wooden and steel members located on both sides of the joint, thereby achieving the effect of being easier to install than conventional wet construction methods.

[0018] Furthermore, according to another fire-resistant covering structure of the present invention, the dry fire-resistant covering material is a fiber-mixed calcium silicate board, which has the effect of enabling construction to be carried out relatively easily and inexpensively.

[0019] In addition, according to another fire-resistant coating structure of the present invention, decorative wood is provided on the outside of the dry fire-resistant coating material, which has the effect of providing a design that harmonizes with the wood-steel components at the joints.

[0020] In addition, according to another fire-resistant coating structure of the present invention, an inorganic filler is provided in the gap between the wood fire-resistant coating material and the dry fire-resistant coating material, which has the effect of reducing heat input to the joint and improving fire resistance performance.

[0021] In addition, according to another fire-resistant coating structure of the present invention, the thickness of the dry fire-resistant coating material is set to a thickness that is greater than or equal to the thickness at which the maximum temperature of the steel member at the joint when heated by fire becomes less than the carbonization temperature, thereby achieving the effect of ensuring the required fire resistance performance.

[0022] Furthermore, according to the method for constructing a fire-resistant coated structure of the present invention, the method for constructing the above-mentioned fire-resistant coated structure includes the steps of joining the ends of the steel frame members to form the joint, providing the non-combustible material on the end face of the wood fire-resistant coating material on the joint side, and providing the dry fire-resistant coating material around the joint, thereby achieving the effect of superior workability compared to conventional wet construction methods. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 shows an embodiment of a fire-resistant covering structure and its construction method according to the present invention, where (1) is a side cross-sectional view and (2) is a horizontal cross-sectional view. [Figure 2] 2(1), (2), and (3) are vertical cross-sectional views taken along lines AA, BB, and CC in FIG. 1(1), respectively. [Figure 3] FIG. 3(1) is a side cross-sectional view of the structure of FIG. 1 with decorative wood applied, and (2) is a cross-sectional view taken along line AA of (1). [Figure 4] Figure 4 shows the test specimen, where (1) is a horizontal cross-section, (2) is a side cross-section, (3) is a diagram of the temperature measurement positions of the steel beams, and (4) is a vertical cross-section along line AA of (2). [Figure 5] Figure 5(1) is a schematic cross-sectional side view showing the test conditions, and (2) is a diagram showing the change in steel beam temperature over time. DETAILED DESCRIPTION OF THE INVENTION

[0024] The following describes in detail an embodiment of a fire-resistant covering structure and its construction method according to the present invention, taking as an example a case where the structure is applied to a joint between wood and steel beams, with reference to the drawings. However, the present invention is not limited to the embodiment.

[0025] As shown in Figures 1 and 2, a fire-resistant coated structure 10 according to an embodiment of the present invention is a fire-resistant coated structure at a joint 14 where wooden-steel beams 12 are butt-joined in the longitudinal direction, and is provided with a non-combustible material 16 and a dry fire-resistant coating material 18.

[0026] The wood-steel beam 12 is a wood-steel member comprising a steel beam 20 (steel member) and a wood-based fire-resistant coating material 22 that provides a fire-resistant coating on the surface of the steel beam 20. The steel beam 20 protrudes in the longitudinal direction from the end of the wood-steel beam 12 on the joint 14 side, and these ends are butt-joined to each other at the joint 14.

[0027] The steel beam 20 is a steel member made of H-shaped steel having a web 24, an upper flange 26, and a lower flange 28. On the upper surface of the upper flange 26, a floor material 30 such as concrete or ALC is provided.

[0028] The wood fire-resistant coating material 22 is a fire-resistant coating material made of a wood material with a predetermined fire-extinguishing performance. This wood fire-resistant coating material 22 is approximately rectangular in cross section when viewed from the longitudinal direction of the wooden-steel beam 12. It fills the recessed space defined by the web 24 and the upper and lower flanges 26, 28 and extends outward beyond the left and right ends of the upper and lower flanges 26, 28 to cover the underside and end face of the lower flange 28 and the end face of the upper flange 26. For example, larch laminated lumber can be used for the wood fire-resistant coating material 22. The thickness of the wood fire-resistant coating material 22 is preferably set so that the maximum temperature of the steel beam 20 is below the carbonization temperature when heated for the required fire resistance period.

[0029] The joint 14 is joined using plates 32 arranged on both the left and right sides of the butted webs 24 along the longitudinal direction of the steel beam 20, plates 34, 36 arranged on both the top and bottom sides of the upper and lower flanges 26, 28 along the longitudinal direction of the steel beam 20, bolts 38 passed through multiple bolt holes opened in each of the plates 32, 34, 36, the web 24, and the upper and lower flanges 26, 28, and nuts 40 screwed onto the tip ends of the bolts 38. Note that in the example of Figures 1 and 2, the plates 34 and nuts 40 arranged on the upper side of the upper flange 26 are not shown because they are embedded in the floor material 30.

[0030] The non-combustible material 16 is attached to the end face 42 (end surface) of the wood fire-resistant covering material 22 on the joint 14 side. This non-combustible material 16 is used to maintain the temperature of the end face 42 below the carbonization temperature so as not to impair the fire resistance of the wood-steel beam 12. It can be made of, for example, a fiber-mixed calcium silicate board or gypsum board. The non-combustible material 16 can be fastened to the end face 42 using adhesives in addition to fastening materials such as screws and nails. This prevents heat from entering through the gap between the non-combustible material 16 and the wood fire-resistant covering material 22, improving fire resistance. By pre-setting a gap of approximately 1 mm between the non-combustible material 16 and the steel beam 20, distortion of the steel beam 20 can be absorbed, making installation of the non-combustible material 16 easier. In this case, the resulting gap between the non-combustible material 16 and the steel beam 20 is preferably filled with an inorganic filler. This reduces the heat input from the joints 14 to the wood fire-resistant covering material 22, further improving fire resistance. The non-combustible material 16 may be made of a board material such as a fiber-mixed calcium silicate board or gypsum board with a thickness of about 35 mm. In this way, the non-combustible material 16 can also be used as a fastening base for the dry fire-resistant covering material 18 installed around the joints 14.

[0031] The dry fire-resistant coating material 18 is a plate-like (board-shaped) material installed around the periphery of the joint 14 to fill the gap between the wood fire-resistant coating materials 22 of the wooden-steel beams 12 located on both sides of the joint 14. The dry fire-resistant coating material 18 is preferably composed of, for example, a fiber-mixed calcium silicate board. Such a material allows for relatively easy and inexpensive application. The thickness of the dry fire-resistant coating material 18 is set to a thickness that ensures that the maximum temperature of the steel beam 20 at the joint 14 during fire heating is below the carbonization temperature. This ensures the required fire resistance. When the dry fire-resistant coating material 18 is composed of a fiber-mixed calcium silicate board, the optimal thickness of the fiber-mixed calcium silicate board can be determined based on the dimensions of the steel beam 20, as shown in the "Relationship between Thickness of the Dry Fire-Resistant Coating Material and Steel Frame Dimensions" section below. In other words, by increasing the thermal capacity of the steel beam 20, the thickness of the fiber-mixed calcium silicate board can be reduced, thereby reducing costs.

[0032] The dry fire-resistant coating material 18 is continuously arranged around the front, rear, and lower sides of the joints 14, excluding the upper side of the joints 14, in a generally U-shaped cross section viewed from the longitudinal direction of the steel beams 20. That is, the dry fire-resistant coating material 18 is composed of a dry fire-resistant coating material 18A on the side surfaces of the joints 14 and a dry fire-resistant coating material 18B on the lower surface of the joints 14. The dry fire-resistant coating material 18A is arranged vertically on the front and rear sides of the joints 14, and its upper end is connected to the underside of the floor material 30. The dry fire-resistant coating material 18B is arranged horizontally below the joints 14, and its both front-to-rear ends are connected to the lower end of the dry fire-resistant coating material 18A. It is desirable to install the dry fire-resistant coating materials 18A and 18B alternately so that the joints 44 of the two materials are not aligned. The dry fire-resistant coating materials 18A and 18B are not in close contact with the joint 14, and a certain space is formed between the dry fire-resistant coating material 18 and the joint 14.

[0033] The dry fire-resistant coating 18A is installed between the upper and lower flanges 26, 28 by fastening it with fastening materials such as nails to a fastening base 46 provided perpendicular to the upper and lower flanges 26, 28. The fastening base 46 is preferably made of a non-combustible material with a certain thickness, such as a 35 mm thick fiber-mixed calcium silicate board. When installing the fastening base 46 between the bolts 38 of the upper and lower flanges 26, 28, installing it through an underlayment 48 made of the same non-combustible material as the fastening base 46 can ensure a more stable installation. Alternatively, the dry fire-resistant coating 18A may be secured using a steel base extending from the web 24 in the front-to-rear direction. This provides a more solid support for the dry fire-resistant coating 18A. In the example shown in the figure, a steel base 52 with an L-shaped cross section extending left and right is fixed to the tip of the protruding steel base 50, which is fixed to two points above and below the web 24, and this steel base 52 is used in combination to fix the dry fire-resistant coating material 18A.

[0034] Dry fire-resistant covering material 18B is installed by fastening its edge to the surface of dry fire-resistant covering material 18A with fastening materials such as nails. Dry fire-resistant covering material 18B may also be fastened to a fastening base attached to the underside of bottom flange 28. This allows dry fire-resistant covering material 18B to be supported more firmly. Note that the example shown in the figure shows a case where steel bases 54 with an L-shaped cross section extending in the front-to-rear direction are fixed to two locations on the left and right sides of the underside of bottom flange 28, and dry fire-resistant covering material 18B is fastened using these steel bases 54.

[0035] The dry fire-resistant coating material 18 is installed to fill the gap between the wood fire-resistant coating materials 22 of the wooden steel beams 12 located on both sides of the joint 14 and to cover the non-combustible material 16. However, by leaving a gap (for example, about 2 mm) where the wood fire-resistant coating material 22 and the dry fire-resistant coating material 18 join, they do not interfere with each other and the installation of the dry fire-resistant coating material 18 becomes easier. In this case, it is preferable to fill the gap between the wood fire-resistant coating material 22 and the dry fire-resistant coating material 18 with an inorganic filler. This reduces the heat input into the joint 14 during a fire and improves fire resistance.

[0036] As shown in Figure 3, decorative wood 56 may be attached to the outside of the dry fire-resistant covering material 18. In this way, it is possible to provide a design that matches the wooden-steel beam 12 at the joint 14. Furthermore, because the dry fire-resistant covering material 18 is in the form of a board, the decorative wood 56 can be attached directly to the dry fire-resistant covering material 18 without using a fastening base. This provides excellent workability.

[0037] Next, an example of a method for constructing the above-mentioned fire-resistant covering structure will be described. First, the ends of the steel beams 20 are joined together to form the joints 14. Meanwhile, non-combustible material 16 is provided on the end surface 42 of the wood fire-resistant covering material 22 on the joint 14 side. The non-combustible material 16 may be provided after the joints 14 are formed. Next, dry fire-resistant covering material 18 is attached around the joints 14. In this manner, the fire-resistant covering structure 10 can be constructed. If decorative wood 56 is to be provided, the dry fire-resistant covering material 18 is first installed around the joints 14, and then the decorative wood 56 is attached to the outside of the dry fire-resistant covering material 18.

[0038] According to this embodiment, the fireproof coating of the joints 14 of the wooden-steel beams 12 is performed by a dry construction method, which has the effect of providing superior workability compared to conventional wet construction methods.

[0039] (Verification of the effects of the present invention) Next, a fire resistance test conducted to verify the effects of the present invention and the results thereof will be described.

[0040] A test specimen was fabricated based on the fire-resistant structure 10 described above, and a fire resistance test was conducted to confirm its fire resistance. Figure 4 shows the shape, dimensions, and temperature measurement locations of the steel beams. The wooden beams 12 used had a 2-hour fire resistance. The steel beams 20 were H-1000 x 300 x 22 x 32. The non-combustible material 16, dry-type fire-resistant material 18, and fastening base 46 were fiber-mixed calcium silicate boards (35 mm thick). The decorative wood 56 was cedar decorative wood (15 mm thick). The flooring 30 was an ALC panel (100 mm thick). Reinforced gypsum boards (21 mm thick x 6) were used as the members 58 on both the left and right ends of the test specimen, and AES blankets (25 mm thick) were used as the members 60 on the outside of these members 58 and on the edge of the flooring 30. The temperature measurement locations for the steel beams 20 were set at positions a to c of cross sections in Figure 4(3).

[0041] The fire resistance test was carried out by placing the test specimen in a furnace and heating it for two hours according to the standard heating curve specified in ISO 834. The standard heating curve specified in ISO 834 is defined by the following formula (1), where T is the furnace temperature [°C] and t is the heating time [minutes].

[0042]

number

[0043] After heating, the specimen was left in the furnace and allowed to cool until it stopped burning and its temperature dropped. An overview of the test conditions is shown in Figure 5(1), and the test results are shown in Figure 5(2).

[0044] As a result of the test, as shown in Figure 5 (2), the temperature of the steel beam in the area of ​​the wooden-steel beam 12 was kept below 200°C (average temperature of cross section a), and it was confirmed that the wood fire-resistant covering material 18 had stopped burning. This confirmed that the fire-resistant covering structure 10 of this example has excellent fire resistance performance.

[0045] (Relationship between thickness of dry fireproof coating material and steel frame dimensions) Next, the relationship between the thickness of the dry fire-resistant coating material and the dimensions of the steel frame will be explained. The maximum temperature T of a steel frame (steel beam 20) fire-resistant coated with a fiber-mixed calcium silicate board (dry-type fire-resistant coating material 18) s According to the following reference 1, is expressed by the following formula (2).

[0046] [Reference 1] "2001 Edition: Explanation of Fire Resistance Verification Method and Calculation Examples and Commentary," Building Guidance Division, Housing Bureau, Ministry of Land, Infrastructure, Transport and Tourism, Building Research Institute, Japan Building Officials Conference, Edited by the Building Center of Japan, Kaibundo Publishing Co., Ltd., 2001

[0047]

number

[0048] In equation (2), t is the heating time, and h and t w are expressed by the following equations (3) and (4), respectively. h is the rate of increase in steel frame temperature per unit time, and t w is the time it takes for the temperature of the steel frame to rise due to the evaporation of water from the fiber-mixed calcium silicate board.

[0049]

number

[0050]

number

[0051] However, H s is the heating perimeter of the steel frame [m], A s is the cross-sectional area of ​​the steel frame [m 2 ], H i is the heating circumference of the fiber-mixed calcium silicate board [m], A i is the cross-sectional area of ​​the fiber-mixed calcium silicate board [m 2 ]. Also, φ=H i / H s , a w =20300, K0=0.00067, R=365, C=0.136.

[0052] As shown in FIG. 5(2), the maximum temperature of the steel beams at the joints in the fire resistance test conducted on the fire-resistant coated structure 10 of this embodiment was lower than the maximum temperature of the steel beams at the joints calculated from Equation (2). This is because the temperature of the steel beams at the joints and the temperature of the steel beams within the wooden-steel beams, which are at lower temperatures, are equalized. Therefore, if the dimensions of the steel beams and the fiber-reinforced calcium silicate boards are designed so that the maximum temperature of the steel beams at the joints calculated from Equation (2) is below the carbonization temperature, the fire resistance of the wooden-steel beams including the joints can be ensured. The relationship between the dimensions of the steel beams and the fiber-reinforced calcium silicate boards so that the maximum temperature of the steel beams calculated from Equation (2) is below 260°C, which is commonly used as the carbonization temperature, is expressed by the following Equation (5).

[0053]

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[0054] The value t in Equation (5) can be considered to be the required fire resistance time for the relevant section. As an example of the dimensions required for a given fire resistance, Table 1 shows an example of the relationship between the thickness of the fiber-reinforced calcium silicate board calculated using Equation (5) and the dimensions of the steel frame at the joint. The given fire resistance can be achieved by setting the thickness of the fiber-reinforced calcium silicate board and the dimensions of the steel frame at the joint to the values ​​shown in Table 1. The symbols in Table 1 correspond to those in Figure 3, and the separation distance d4 between the steel frame and the fiber-reinforced calcium silicate board is set to 50 mm. Also, in Table 1, 1-hour fire resistance, 2-hour fire resistance, and 3-hour fire resistance indicate fire resistance of 1 to 3 hours, respectively.

[0055] [Table 1]

[0056] As explained above, the fire-resistant coating structure of the present invention is a fire-resistant coating structure at a joint where the ends of steel frame members protruding from wooden and steel members are joined, the fire-resistant coating structure comprising steel frame members and a wood fire-resistant coating material made of a wood material that provides fire-resistant coating to the surface of the steel frame members, and the fire-resistant coating structure comprises a non-combustible material provided on the end surface of the wood fire-resistant coating material on the joint side, and a plate-shaped dry fire-resistant coating material provided around the joint so as to seal the gap between the wood fire-resistant coating materials of the wooden and steel members located on both sides of the joint, making it easier to install than conventional wet construction methods.

[0057] Furthermore, in another fire-resistant covering structure according to the present invention, the dry fire-resistant covering material is a fiber-mixed calcium silicate board, so that it can be installed relatively easily and inexpensively.

[0058] In addition, according to another fire-resistant coating structure of the present invention, decorative wood is provided on the outside of the dry fire-resistant coating material, so that a design that harmonizes with the wood-steel components can be imparted at the joint.

[0059] In addition, according to another fire-resistant coating structure of the present invention, an inorganic filler is provided in the gap between the wood fire-resistant coating material and the dry fire-resistant coating material, thereby reducing heat input to the joint and improving fire resistance performance.

[0060] In addition, according to another fire-resistant coating structure of the present invention, the thickness of the dry fire-resistant coating material is set to a thickness that is greater than or equal to the thickness at which the maximum temperature of the steel member at the joint when heated by fire becomes less than the carbonization temperature, thereby ensuring the required fire resistance performance.

[0061] Furthermore, according to the construction method for a fire-resistant covering structure of the present invention, the method for constructing the above-mentioned fire-resistant covering structure includes the steps of joining the ends of the steel frame members to form the joint, providing the non-combustible material on the end face of the wood fire-resistant covering material on the joint side, and providing the dry fire-resistant covering material around the joint, and therefore has superior construction properties to conventional wet construction methods.

[0062] The Sustainable Development Goals (SDGs) are 17 international goals adopted at the United Nations Summit in September 2015. The fire-resistant coating structure and its construction method according to this embodiment can contribute to achieving one of the 17 SDGs, for example, goal 11, "Make cities and towns inclusive and sustainable." [Industrial Applicability]

[0063] As described above, the fire-resistant covering structure and its construction method according to the present invention are useful for fire-resistant covering structures for joints of steel frame members, and are particularly suitable for improving construction efficiency. [Explanation of symbols]

[0064] 10 Fire-resistant covering structure 12 Wood-steel beams (wood-steel members) 14 Joint 16 Noncombustible materials 18 Dry fireproof cladding 20 Steel beams (steel members) 22 Wooden fireproof cladding 30 Flooring 32~36 Plates 38 volts 42 Small side 56 Decorative wood

Claims

1. A fire-resistant coating structure at a joint where the ends of the steel frame members protruding from a wood-steel member are joined together, the wood-steel member comprising a steel frame member and a wood fire-resistant coating material made of a wood material that fire-resistantly coats the surface of the steel frame member, A fire-resistant coating structure characterized by comprising a non-combustible material provided on the end surface of the wood fire-resistant coating material on the joint side, and a plate-shaped dry fire-resistant coating material provided around the joint so as to seal the gap between the wood fire-resistant coating materials of the wood-steel members located on both sides of the joint.

2. 2. The fire-resistant covering structure according to claim 1, wherein the dry fire-resistant covering material is a fiber-mixed calcium silicate board.

3. 2. The fire-resistant covering structure according to claim 1, wherein a decorative wood is provided on the outside of the dry fire-resistant covering material.

4. 2. The fire-resistant covering structure according to claim 1, wherein an inorganic filler is provided in a gap between the wood fire-resistant covering material and the dry fire-resistant covering material.

5. The fire-resistant coating structure according to claim 1, characterized in that the thickness of the dry fire-resistant coating material is set to a thickness that is greater than or equal to the thickness at which the maximum temperature of the steel member at the joint when heated by a fire becomes less than the carbonization temperature.

6. A method for installing the fire-resistant covering structure according to any one of claims 1 to 5, A construction method for a fire-resistant covering structure, comprising the steps of joining the ends of the steel frame members to form the joint, providing the non-combustible material on the end surface of the wood fire-resistant covering material on the joint side, and providing the dry fire-resistant covering material around the joint.

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