JP7446855B2 - Fireproof coating structure and its construction method - Google Patents

Description

The present invention relates to a fire-resistant coating structure in which the surfaces of columns and beams of structures are coated with different types of fire-resistant coating materials in the direction of the material axis, and in particular, one side in the direction of the material axis is coated with fire-resistant paint, and the other side is covered with fire-resistant molding. This invention relates to a fireproof coating structure covered with a board and its construction method.

Conventionally, when a structure using steel materials, such as a steel structure building, is exposed to a fire, the strength and rigidity of the steel material decreases due to the rise in temperature, leading to the risk of the structure collapsing. Therefore, beams and columns of steel structures are coated with a fireproof coating in order to suppress temperature rise due to heating by fire (see, for example, Patent Document 1).

One type of fire-resistant coating material is fire-resistant paint containing ammonium polyphosphate as a main component. When fire-resistant paint receives heat during a fire, it starts foaming at around 250°C, expands 20 to 30 times as much, and forms a heat insulating layer that suppresses the rise in temperature of steel materials.

When considering a specification in which one side of a steel beam in the axial direction is coated with fire-resistant paint and the other side is coated with another fire-resistant coating material such as rock wool, the fire-resistant performance in that case is The fit of the connecting part (joint part) with the fireproof covering material is important. Depending on the extent of this, the heat insulating performance of the fire-resistant paint or other fire-resistant coating materials may not be effectively exhibited, and there is a possibility that a predetermined fire-resistant performance may not be obtained.

In order to solve such problems, the present inventor has already proposed a fireproof covering structure described in Patent Document 2. This fire-resistant coating structure includes a foamable fire-resistant paint that is provided on a first region of the surface of the section steel and foams when heated, and a second region of the surface of the section steel that is adjacent to the first region. The ends are made of non-foamed rock wool overlaid on a fire-resistant paint surface. According to this, it is possible to ensure fire resistance performance at the boundary between different types of fire resistant coating materials.

Japanese Patent Application Publication No. 11-222958 Patent Application No. 2019-041848 (unpublished at this time)

By the way, when one side in the axial direction of a steel beam is coated with fire-resistant paint and the other side is coated with fire-resistant molded board instead of rock wool, the fire-resistant performance of the boundary between the fire-resistant paint and the fire-resistant molded board is evaluated. A structure that could be secured was needed.

The present invention has been made in view of the above, and an object of the present invention is to provide a fire-resistant coating structure and a construction method thereof that can ensure fire-resistant performance at the boundary between a fire-resistant paint and a fire-resistant molded plate.

In order to solve the above-mentioned problems and achieve the objects, a fire-resistant coating structure according to the present invention includes different types of fire-resistant coating materials that cover different regions of the longitudinal surface of a section steel, and It is a fireproof coating structure in which the ends of the materials are overlapped with each other with a predetermined overlap margin, and the fireproof coating materials of different types are provided in a first region of the surface of the section steel and have a foaming property that foams when heated. fire-resistant paint, and a non-foaming fire-resistant formed plate provided in a second region of the surface of the section steel adjacent to the first region, the end of which is overlapped with the surface of the fire-resistant paint. shall be.

Further, in another fire-resistant coating structure according to the present invention, in the above-mentioned invention, the section steel is an H-section steel, and the end side of the fire-resistant formed plate is provided to overlap the surface of the fire-resistant paint in the first area. A first member arranged as a closing plate in a space defined by the web and flange of the section steel, and a space provided adjacent to the first member and defined by the web and flange of the second region. It is characterized in that it includes a second material arranged as a spacer, and a third material that covers the first material, the second material, and the flange from the outside.

Further, another fire-resistant coating structure according to the present invention is characterized in that, in the above-mentioned invention, the overlap margin of the fire-resistant molded plate with respect to the fire-resistant paint is 15 mm or more.

Furthermore, the method for constructing a fire-resistant coating structure according to the present invention is a method for constructing the fire-resistant coating structure described above, in which a fire-resistant coating is applied to a first region on the surface of a section steel, and then a fire-resistant coating is applied to a second region and a fire-resistant coating structure. It is characterized by the construction of a fireproof molded board on the surface of the paint.

According to the fireproof coating structure according to the present invention, different types of fireproof coating materials are provided which respectively cover different regions of the longitudinal surface of the section steel, and the ends of the different types of fireproof coating materials are arranged with a predetermined overlap margin between them. A fire-resistant coating structure in which different types of fire-resistant coating materials are stacked on each other include a foamable fire-resistant paint provided on a first region of the surface of the section steel and foamed by heating, and a fire-resistant coating material adjacent to the first region. It consists of a non-foaming fire-resistant molded plate provided on the second area of the surface of the section steel and whose end portion is overlapped with the surface of the fire-resistant paint, so it can be easily constructed, and the fire-resistant paint and the fire-resistant molded plate can be easily constructed. This has the effect of ensuring fire resistance at the boundary.

Further, according to another fire-resistant coating structure according to the present invention, the shaped steel is an H-shaped steel, and the end side of the fire-resistant formed plate is provided overlappingly with the surface of the fire-resistant paint in the first region, and the shaped steel A first material arranged as a closing plate in a space defined by the web and the flange of the second region, and a spacer provided adjacent to the first material and arranged as a spacer in the space defined by the web and the flange of the second region. Since it is composed of the second material, which is coated with the first material, the third material that covers the first material, the second material, and the flange from the outside, the boundary between the fire-resistant paint that coats the H-shaped steel and the fire-resistant molded plate is It has the effect of being easy to construct and ensuring its fire resistance performance.

Further, according to another fireproof coating structure according to the present invention, since the overlapping margin of the fireproof molded plate with respect to the fireproof paint is 15 mm or more, it is possible to ensure fireproof performance for, for example, one hour.

Further, according to the method for constructing a fire-resistant coating structure according to the present invention, the method for constructing the fire-resistant coating structure described above includes applying a fire-resistant paint to a first region of the surface of a section steel, and then applying a fire-resistant coating to a second region. Since the fireproof molded plate is applied to the surface of the fireproof paint, it is possible to perform the work easily, and the fireproof performance of the boundary between the fireproof paint and the fireproof molded plate can be ensured.

FIG. 1 is a diagram showing an embodiment of a fireproof coating structure according to the present invention. FIG. 2 is an overall view showing an embodiment of the fireproof coating structure according to the present invention, in which (1) is a side view, (2) is a cross-sectional view along line AA, and (3) is a sectional view along line BB. (4) is a cross-sectional view taken along line CC. FIG. 3 is a partial view showing an embodiment of the fireproof covering structure according to the present invention, in which (1) is a side view, (2) is a cross-sectional view taken along line DD, and (3) is a sectional view taken along line EE. It is a sectional view along the line. FIG. 4 is a diagram showing the test specimen and thermocouple positions used in the fire resistance test, in which (1) is a side view and (2) is a cross-sectional view. FIG. 5 is a list of dimensions of the test specimens used in the fire resistance test. FIG. 6 is a diagram showing test results regarding 1-hour fire resistance performance. FIG. 7 is a diagram showing test results regarding 2-hour fire resistance performance.

EMBODIMENT OF THE INVENTION Below, embodiment of the fireproof covering structure and its construction method based on this invention is described in detail based on drawing. In this embodiment, when constructing a frame as shown in FIG. 1 using pre-coated members, it is assumed that joints and joints are coated with a fireproof material of a different type. Note that the present invention is not limited to this embodiment.

As shown in FIG. 1, a fireproof coating structure 10 according to an embodiment of the present invention includes a fireproof coating that covers different regions R1 (first regions) in the longitudinal direction of a beam 12 made of H-shaped steel (shape steel). 14, and a refractory molded plate 16 (a different type of refractory covering material) that covers the region R2 (second region).

FIG. 2 is an enlarged view of the main parts. FIG. 3 is a partial view of FIG. 2 with illustration of the outer covering portion omitted.
As shown in these figures, the beam 12 has a web 18, an upper flange 20, and a lower flange 22, and a floor slab 24 made of reinforced concrete slab or ALC slab is provided on the upper surface of the upper flange 20.

The fireproof paint 14 is a foaming material that expands and increases in thickness when heated, and is provided by painting or the like on the entire surface of the web 18 and the lower flange 22, as well as the edge and lower surface of the upper flange 20. The thickness t1 of the fireproof paint 14 is set to be much smaller than the thickness t2 of the fireproof molded plate 16. The refractory molded plate 16 is a non-foamable plate-shaped plate, and can be formed of, for example, a calcium silicate refractory coating plate. The refractory molded plate 16 is composed of pieces A1 and A2 (third material), piece B (second material), and piece C (first material). Pieces A1, A2, B, and C have the same thickness t2, but the thicknesses of B and C may be greater than or equal to the thicknesses of A1 and A2. At the boundary 26 between the fireproof paint 14 and the fireproof molded board 16, the end 16A of the fireproof molded board 16 is overlapped with the end 14A of the fireproof paint 14 with an overlapping margin W in between.

The piece A1 is a rectangular side plate placed on the side of the beam 12. This piece A1 is provided on the side facing the web 18 from the lower surface of the floor slab 24 to the lower side of the lower flange 22. Piece A2 is a rectangular bottom plate placed on the lower surface of beam 12. This piece A2 is provided at the bottom facing the lower surface of the lower flange 22. The lower end of piece A1 and the edges at both widthwise ends of piece A2 are fixed with screws, nails, etc. (not shown). Pieces A1 and A2 cover pieces B and C, which will be described later, and a lower flange 22 from the outside.

Piece B is a substantially rectangular plate arranged as a spacer in the space defined by the web 18 and the upper and lower flanges 20 and 22 in the region R2. A plurality of pieces B are provided at positions adjacent to piece C, which will be described later, and at positions separated by predetermined intervals from there in the longitudinal direction of the beam 12. The upper and lower corners of the inner edge of piece B are chamfered. The reason for chamfering is to avoid interference between the web 18 and the rounded shape of the welded portion of the upper and lower flanges 20 and 22. The outer edge of piece B is located on the outer side of the edges of the upper and lower flanges 20 and 22. A small triangular plate-shaped wedge 30 is inserted between the lower edge of piece B and the lower flange 22. The inner edge and upper and lower edges of piece B are secured to web 18 and upper and lower flanges 20, 22, respectively, with adhesive 28. Piece A1 is fixed to the outer edge of piece B with a plurality of screws and an adhesive 28 (not shown).

The piece C is a substantially rectangular plate that is provided overlapping the surface of the fireproof paint 14 in the region R1 and is arranged as a closing plate in the space defined by the web 18 and the upper and lower flanges 20 and 22. The thickness t2 of the piece C corresponds to the overlap W. The upper and lower corners of the inner edge of piece C are chamfered. The reason for chamfering is to avoid interference between the web 18 and the rounded shape of the welded portion of the upper and lower flanges 20 and 22. A small triangular plate-shaped wedge 30 is inserted between the lower edge of the piece C and the fireproof paint 14 of the lower flange 22. The inner edge and upper and lower edges of piece C are fixed to the web 18 and the surface of the fireproof coating 14 of the upper and lower flanges 20, 22 with an adhesive 28. The outer edge of piece C is covered by piece A1.

The adhesive 28 used to bond the pieces A1, A2, B, and C may be, for example, a sodium silicate adhesive or a sealant.

Next, a method of constructing the fireproof covering structure 10 described above will be explained. Here, we will take as an example a case in which piece C is installed on beam 12 where fireproof paint 14 is applied in area R1, then pieces B, A1, and A2 are installed in that order, and finally joint treatment is performed with adhesive. explain.

First, adhesive is applied to the edges around the piece C whose dimensions have been adjusted. Subsequently, the piece C is placed on the surface of the fireproof paint 14 in the region R1, and the wedge 30 is inserted into the lower part of the piece C. Next, an adhesive is applied to the periphery of the piece B whose dimensions have been adjusted, and this piece B is temporarily fixed adjacent to the region R2 side of the piece C. Thereafter, a wedge 30 is inserted into the lower part of piece B to permanently fix it, and pieces B and C are made to face each other by sanding the sides as necessary.

Next, piece A1 is fastened to piece B with screws, nails, etc., and then piece A2 is fastened to piece A1 with screws, nails, etc. Thereafter, adhesive is applied to the surfaces of piece C and fireproof paint 14 and to the joints of piece A1. Then, adhesive is applied to the joint between the piece A2 and the surface of the fireproof paint 14. Thereafter, the surfaces of the piece C and the fire-resistant paint 14 and the joints of the piece A1 are pressed and filled with adhesive. Also, the adhesive is pushed into and filled into the joint between the piece A2 and the surface of the fireproof paint 14. According to the above procedure, the fireproof covering structure 10 described above can be constructed.

According to the fire-resistant coating structure 10 of the present embodiment, it is possible to ensure the fire-resistant performance not only of the boundary area 26 but also of the entire area without locally increasing the thickness of the foamable fire-resistant paint 14 at the boundary area 26. can. Therefore, the present embodiment can be constructed more easily than the conventional structure described above, and can ensure the fire resistance performance of the boundary portion 26 between different types of fire-resistant coating materials. Moreover, the appearance of the boundary portion 26 from the region R1 side can be improved. This embodiment is particularly effective in ensuring fireproof performance at the boundary when a joint or a joint is coated with a different material for fireproofing when constructing a frame using pre-coated members.

In the above embodiment, the thickness t1 of the fireproof paint 14, the thickness t2 of the fireproof molded plate 16 (pieces A1, A2, B, C), and the overlapping margin W are set as appropriate within a range that does not impede the effects of the present invention. Can be changed. For example, as shown in the test results described later, in order to ensure one-hour fire resistance, the thickness t1 of the fire-resistant paint 14 is set to about 1.75 mm, and the thickness t2 of the fire-resistant molded plate 16 is set to about 15 mm or more. Good too. Further, in order to ensure fire resistance performance for two hours, the thickness t1 of the fire-resistant paint 14 may be set to about 4.80 mm, and the thickness t2 of the fire-resistant molded plate 16 may be set to about 25 mm or more. The overlapping margin W is preferably set to be approximately equal to or greater than the thickness t2 of the refractory molded plate 16, and is desirably set to approximately 35 mm.

Further, in the above embodiment, the case where H-shaped steel is coated with fire-resistant paint and fire-resistant molded plate has been explained as an example, but the present invention is not limited to H-shaped steel, and for example, channel steel, angle-shaped steel, etc. It can also be applied when coating steel etc. with fire-resistant paint and fire-resistant molded plates. Even in this case, the same effects as described above can be achieved.

(Verification of effects of the present invention)
Next, the tests and results conducted to verify the effects of the present invention will be explained.

This test investigated the fire resistance performance (1-hour fire resistance performance, 2-hour fire resistance performance) of the joint portion of different fire-resistant covering materials during loading in the fire-resistant covering structure according to the present invention.

FIG. 4 is a schematic diagram of the test specimen. The numbers (1 to 21) in the figure are thermocouple numbers (temperature measurement positions). As shown in this figure, the test specimen was composed of a steel beam (H-beam) covered with fire-resistant paint and fire-resistant molded plates. The H-shaped steel used was SM490A, H-400 x 200 x 8 x 13 mm. An ALC plate with a thickness of 100 mm and a width of 600 m was attached to the upper side of the beam using stud bolts to simulate a floor. Fireproof Tect (registered trademark) manufactured by Kansai Paint Co., Ltd. was used as the fireproof paint. New Taicalite No. 2 manufactured by Nippon Insulation Co., Ltd. (Taicalite is a registered trademark) was used as the fireproof molded plate. The structure of the boundary part described above was applied to the joint part, and the general parts other than the joint part were designed in accordance with the fitting and construction instructions specified for the fireproof molded board. FIG. 5 shows the shape, dimensions, etc. of each piece used for the connecting part. The joints were installed in the order of piece C (closing plate), piece B (spacer), piece A1 (side plate), and piece A2 (bottom plate), and finally, the joints were treated with adhesive. The thickness of the main material of the fire-resistant paint was 1.75 mm (for the 1-hour fire-resistance test specimen) and 4.80 mm (for the 2-hour fire-resistance test specimen). The overlap between piece C and the fireproof paint was 35 mm.

1 in accordance with the fireproofing performance test/evaluation procedure manual for a test specimen (1-hour fireproof test specimen) coated with a fire-resistant paint with a 1-hour fire-resistance specification and a fire-resistant molded board with a 1-hour fire-resistance specification. The results of the time fire resistance test (temperature measurement results) are shown in FIG. In addition, the test specimen (2-hour fire-resistance test specimen) was coated with a fire-resistant paint with a 2-hour fire-resistance specification and a fire-resistant molded plate with a 2-hour fire-resistance specification, in accordance with the fire-retardant performance test and evaluation procedure manual. Figure 7 shows the results of a 2-hour fire resistance test (temperature measurement results).

Note that the load on the test specimen was two-line loading at three equally divided points, and heating was performed with a long-term allowable bending moment (long-term allowable tensile stress) acting on the beam. For heating, the time course of temperature measured by a thermocouple is determined according to ISO834-Part. Heating was carried out along the standard heating temperature curve of No. 1. The heating time was 60 minutes, and after the heating was completed, the steel material temperature began to fall and the steel material was allowed to cool while continuing to be loaded until the displacement became stable. Then, measure the furnace temperature, specimen temperature, specimen displacement, and load, and if the deflection amount or deflection rate of the beam exceeds the specified value (maximum deflection amount 182.25 mm, maximum deflection rate 8.10 mm/min) It was determined that the test specimen could no longer support the load.

As a general guideline, unless the steel temperature of the steel beam is 550℃ or less, the steel beam will not be able to support the long-term allowable bending moment, but as shown in Figures 6 and 7, at the center of the span (fireproof coating joint) The temperature of the steel material in all cross sections is below 550°C, about 450°C, about 380°C on the fireproof molded plate side, and about 500°C on the fireproof paint side. The highest temperature of the steel material is the fireproof molded plate side < the center of the span < the fireproof paint side, and the joints of the fireproof coating are not weak points. In this way, the maximum temperature of the steel material was 550℃ or less, and the amount of deflection and the rate of deflection did not exceed the specified values. It was confirmed that the 1-hour fire resistance was satisfied, and the 2-hour fire resistance was satisfied as shown in FIGS. 7 (4) and (5).

According to this embodiment, a synthetic fireproof coating construction method in which a fireproof paint and a fireproof molded board are combined in the axial direction of the beam becomes possible. As a result, fire-resistant paint is applied (pre-coated) to steel beams at a factory such as a steel fabricator, and after the beams are transported to the site and erected, the remaining uncoated areas are coated with fire-resistant formed plates (dry fire-resistant coating) on-site. It is possible to apply fireproof coating to the area as shown in Figure 1. As a result, it becomes possible to save labor, shorten the construction period, and improve the environment during fireproof coating work on site.

As explained above, the fireproof coating structure according to the present invention includes different types of fireproof coating materials that respectively cover different regions of the longitudinal surface of the section steel, and the ends of the different types of fireproof coating materials are connected to each other. A fire-resistant coating structure in which different types of fire-resistant coating materials are overlapped with each other with a predetermined overlap margin, a fire-resistant coating material of different types is provided on a first area of the surface of a section steel, and a foamable fire-resistant paint that foams when heated; It consists of a non-foaming fireproof molded plate provided in a second area of the surface of the section steel adjacent to the first area and whose end portion is overlapped with the surface of the fireproof paint, so it can be easily constructed, and It is possible to ensure fireproof performance at the boundary between the fireproof paint and the fireproof molded board.

Further, according to another fire-resistant coating structure according to the present invention, the shaped steel is an H-shaped steel, and the end side of the fire-resistant formed plate is provided overlappingly with the surface of the fire-resistant paint in the first region, and the shaped steel A first material arranged as a closing plate in a space defined by the web and the flange of the second region, and a spacer arranged adjacent to the first material in a space defined by the web and the flange of the second region. Since the structure includes the second material, which is coated with the first material, the third material that covers the first material, the second material, and the flange from the outside, the boundary between the fire-resistant paint that coats the H-shaped steel and the fire-resistant molded plate is It can be easily constructed and its fire resistance performance can be ensured.

Further, according to another fireproof coating structure according to the present invention, since the overlapping margin of the fireproof molded plate with respect to the fireproof paint is 15 mm or more, fireproof performance can be ensured for, for example, one hour.

Further, according to the method for constructing a fire-resistant coating structure according to the present invention, the method for constructing the fire-resistant coating structure described above includes applying a fire-resistant paint to a first region of the surface of a section steel, and then applying a fire-resistant coating to a second region. Since the refractory molded board is applied to the surface of the fireproof paint, construction is easy and the fireproof performance of the boundary between the fireproof paint and the refractory molded board can be ensured.

As described above, the fire-resistant coating structure and its construction method according to the present invention are useful for ensuring fire-resistant performance at the boundary between the fire-resistant paint and the fire-resistant molded plate that cover different regions in the longitudinal direction of the shaped steel, It is especially suitable for easy construction.

10 Fireproof coating structure 12 Beam (shaped steel)
14 Fireproof paint 14A, 16A End 16 Fireproof molded board 18 Web 20 Upper flange 22 Lower flange 24 Floor slab 26 Boundary 28 Adhesive 30 Wedge A1, A2 Piece (third material)
B Piece (second material)
C piece (first material)
R1 area (first area)
R2 area (second area)
t1, t2 Thickness W Overlapping allowance

Claims (3)

A fireproof coating structure comprising different types of fireproof coating materials covering different regions of the longitudinal surface of the section steel, and in which the ends of the different types of fireproof coating materials are overlapped with each other with a predetermined overlap margin. ,
The different types of fire-resistant coatings include a foamable fire-resistant coating that is provided on a first region of the surface of the section steel and foams upon heating, and a second region of the surface of the section steel that is adjacent to the first region. It consists of a non-foaming fire-resistant molded plate whose ends are overlaid on the surface of fire-resistant paint,
The shaped steel is an H-shaped steel, and the end side of the fire-resistant formed plate is provided overlapping the surface of the fire-resistant paint in the first area and is arranged as a closing plate in the space defined by the web and flange of the shaped steel. a first material, a second material provided adjacent to the first material and arranged as a spacer in a space defined by the web and flange of the second region; A fireproof covering structure comprising: a third material covering the flange from the outside . The fireproof coating structure according to claim 1, wherein the overlap margin of the fireproof molded plate to the fireproof paint is 15 mm or more. A method for constructing the fireproof covering structure according to claim 1 or 2 , comprising:
A method for constructing a fire-resistant coating structure, comprising applying a fire-resistant paint to a first area of the surface of a shaped steel, and then applying a fire-resistant molded plate to a second area and the surface of the fire-resistant paint.

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