Spray fireproofing

Abstract

To provide a spray fire-resistant coating material in which rock wool and a hydraulic composition are mixed, capable of reducing the generation amount of carbon dioxide caused by the production of cement.SOLUTION: A spray fireproof coating material in which rock wool and a hydraulic composition are mixed is characterized in that the hydraulic composition contains 70 parts by mass or more and 80 parts by mass or less of blast furnace slag fine powder and 20 parts by mass or more and 30 parts by mass or less of a calcium-based admixture with respect to 100 parts by mass of the hydraulic composition, and a water content of the spray fireproof coating material is 2.0 mass% or more and 4.3 mass% or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a spray-applied fire-resistant coating material that is a mixture of rock wool and a hydraulic composition. [Background technology]

[0002] Sprayed rock wool has been used as a fire-resistant coating material for steel-framed buildings. Conventional sprayed rock wool contains cement (Portland cement) and rock wool as its main components. For example, Patent Document 1 discloses a sprayed rock wool material containing a cement-containing binder for fiber spraying and rock wool as its main components. As described above, conventional sprayed rock wool contains cement, but a large amount of carbon dioxide is generated during the production of cement. Therefore, conventional sprayed rock wool has room for improvement from the viewpoint of reducing carbon dioxide emissions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7232657 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a spray-applied fire-resistant coating material that is a mixture of rock wool and a hydraulic composition, and that can reduce the amount of carbon dioxide generated due to the production of cement. [Means for solving the problem]

[0005] A spray-on fire-resistant coating material comprising a mixture of rock wool and a hydraulic composition according to an embodiment of the present disclosure is characterized in that the hydraulic composition contains 70 to 80 parts by mass of finely powdered blast furnace slag and 20 to 30 parts by mass of a calcium-based admixture when the hydraulic composition is taken as 100 parts by mass, and the moisture content of the spray-on fire-resistant coating material is 2.0 to 4.3% by mass.

[0006] According to an embodiment of the present disclosure, the sprayed fire-resistant coating material is composed of rock wool and a hydraulic composition containing finely powdered blast furnace slag, and therefore can reduce carbon dioxide emissions resulting from cement production compared to conventional sprayed rock wool materials that mix rock wool and cement.

[0007] In the spray-on fire-resistant coating material according to an embodiment of the present disclosure, when the spray-on fire-resistant coating material is taken as 100 parts by mass, the contents of the rock wool and the hydraulic composition are in the following blending ratios (1) to (3): (1) 60 parts by mass of the rock wool and 40 parts by mass of the hydraulic composition (2) 40 parts by mass of the rock wool and 60 parts by mass of the hydraulic composition (3) The rock wool is more than 40 parts by mass but less than 60 parts by mass, and the hydraulic composition is the part by mass obtained by subtracting the part by mass of the rock wool. The present invention is characterized in that the present invention is any one of the following:

[0008] According to an embodiment of the present disclosure, the sprayed fire-resistant coating material is a mixture of rock wool and a hydraulic composition at the same mass ratio as conventional sprayed rock wool. As a result, the sprayed fire-resistant coating material of this embodiment can easily ensure a slurry concentration equivalent to that of conventional sprayed rock wool. Furthermore, because the sprayed fire-resistant coating material is composed of the same mass ratio and slurry concentration as conventional sprayed rock wool, a predetermined coating thickness can be ensured using a spraying device for conventional sprayed rock wool.

[0009] The sprayed fire-resistant coating material according to an embodiment of the present disclosure is characterized in that the hydraulic composition does not contain cement. According to an embodiment of the present disclosure, the sprayed fire-resistant coating material is composed of rock wool and a hydraulic composition that does not contain cement, and therefore can reduce carbon dioxide emissions caused by cement production compared to conventional sprayed rock wool materials that mix rock wool and cement. [Effects of the Invention]

[0010] The sprayed fire-resistant coating material according to an embodiment of the present disclosure is composed of rock wool and a hydraulic composition that does not contain cement, and therefore can reduce the amount of carbon dioxide generated due to the production of cement compared to conventional sprayed rock wool materials. [Brief explanation of the drawings]

[0011] [Figure 1A] FIG. 2 is a side view showing the shape of a test specimen used in the examples. [Figure 1B] FIG. 1B is a cross-sectional view taken along the line IB-IB in FIG. 1A. [Figure 1C] 1B is a cross-sectional view taken along line IC-IC in FIG. 1A, showing the temperature measurement positions of the test specimens used in the examples. [Figure 1D] FIG. 1B is a cross-sectional view taken along line ID-ID in FIG. 1A, showing the temperature measurement positions in the test used in the examples. [Figure 1E] FIG. 1 is a plan view showing displacement measurement positions of a test specimen used in an example. [Figure 2] FIG. 1 is a schematic diagram showing the setup state in a loaded heating test of an example. [Figure 3] 1 is a graph showing a comparison of the maximum temperature history of steel beams in specimens No. 1 to No. 5 in the examples. [Figure 4] 1 is a graph showing a comparison of the temperature history of steel beams in specimens No. 1 and No. 4 in the examples. [Figure 5A] 10 is a photograph showing the condition of test piece No. 1 after the experiment. [Figure 5B] 10 is a photograph showing the condition of test piece No. 4 after the experiment. [Figure 5C]This is a photograph showing the condition of the steel beams of specimen No. 1 after the experiment. [Figure 6] 1 is a graph showing the relationship between deflection (displacement) and time for No. 1 in the examples. [Figure 7] 10 is a graph showing the deflection (displacement) distribution of No. 1 in the examples. [Figure 8] 10 is a graph showing the relationship between vertical deflection (displacement) and time for No. 4 in the examples. [Figure 9] 10 is a graph showing the deflection (displacement) distribution of No. 4 in the examples. [Figure 10] 10 is a graph showing a comparison of the relationship between beam center deflection (displacement) and time for No. 1 to No. 5 in the examples. [Figure 11] 10 is a graph showing a comparison of the deflection (displacement) speed at the center position of No. 1 to No. 5 in the examples. DETAILED DESCRIPTION OF THE INVENTION

[0012] The present invention relates to a spray-on fireproof coating material comprising a mixture of rock wool and a cement-free hydraulic composition. The hydraulic composition contains 70 to 80 parts by mass of ground blast furnace slag and 20 to 30 parts by mass of a calcium-based admixture, based on 100 parts by mass of the hydraulic composition. The spray-on fireproof coating material has a bulk density of 0.28 g / cm. 3 The above-mentioned components are mixed at a slurry concentration of 33% by mass or more and 43% by mass or less. The embodiments will be described below with reference to the drawings. However, the following embodiments are merely examples of spray-applied fire-resistant coating materials for realizing the technical concept of the present embodiments, and are not intended to be limiting.

[0013] The sprayed fireproof coating material of the embodiment contains rock wool and a hydraulic composition. The hydraulic composition contains 70 to 80 parts by mass of ground blast furnace slag and 20 to 30 parts by mass of a calcium-based admixture, based on 100 parts by mass of the hydraulic composition. The sprayed fireproof coating material has a bulk density of 0.28 g / cm.3 or more, and the slurry concentration is 33 mass % or more and 43 mass % or less.

[0014] Rock wool is, for example, a material obtained by fiberizing raw mineral. Specific examples include at least one type of rock wool, such as SiO2-CaO-MgO-Al2O3-based or SiO2-Al2O3-based. Rock wool is obtained, for example, by melting a mixture of raw mineral materials in a cupola furnace or an electric furnace and fiberizing the mixture using a blowing method or a spinning method using a high-speed rotor. The raw mineral materials may have a composition of, for example, 35-55% by mass of SiO2, 10-20% by mass of Al2O3, 5-40% by mass of MgO, 0.5-40% by mass of CaO, 0-10% by mass of FeO, and 0-10% by mass of trace components such as Cr2O3, Na2O, KO, TiO2, and MnO.

[0015] The hydraulic composition contains blast furnace slag instead of the cement contained in conventional sprayed rock wool. By containing blast furnace slag instead of cement, the hydraulic composition can reduce carbon dioxide emissions resulting from the production of cement. The hydraulic composition may contain a trace amount of cement, but preferably does not contain cement. By not containing cement, the hydraulic composition can further reduce carbon dioxide emissions resulting from the production of cement. The hydraulic composition contains 70 to 80 parts by mass of ground blast furnace slag and 20 to 30 parts by mass of calcium-based admixture when the hydraulic composition is taken as 100 parts by mass. When the hydraulic composition is in this blending ratio, the desired slurry concentration can be achieved.

[0016] Ground granulated blast furnace slag is blast furnace slag in powder form. Blast furnace slag is a mixture of components other than iron, such as silica contained in iron ore, and ash from coke, which is used as a reducing agent, combined with limestone, an auxiliary raw material. As the blast furnace slag, it is preferable to use ground granulated blast furnace slag used in JIS (Japanese Industrial Standards) R5211 "Blast furnace cement" or ground granulated blast furnace slag conforming to JIS A6206 "Blast furnace slag for concrete." In addition, blast furnace slag has a specific surface area of ​​2000 to 10000 cm. 2 / g, preferably 3500 to 7000 cm 2 It is preferable to use one having a hydroxyl group content of 1 / g. Furthermore, by using blast furnace slag powder as the hydraulic composition material, the sprayed fireproof coating material is whiter than conventional sprayed rock wool. Emissivity tends to be higher when the color is black and lower when the color approaches white. Therefore, the fireproof performance of the sprayed fireproof coating material can be improved from the viewpoint of emissivity as well. Furthermore, because the sprayed fireproof coating material is white, its emissivity is less likely to change even if it deteriorates over time.

[0017] The calcium-based admixture is a substance (stimulant) that activates the latent hydraulic properties of the blast furnace slag fine powder, thereby enabling the blast furnace slag fine powder to exhibit its hydraulic properties. The calcium-based admixture contains, for example, at least one of an expanding agent, limestone fine powder, and slaked lime. While the blending ratios are not particularly limited, a preferred blending ratio is, for example, 31 parts by mass of the expanding agent, 37 parts by mass of the limestone fine powder, and 32 parts by mass of slaked lime, based on 100 parts by mass of the calcium-based admixture. By blending the calcium-based admixture in this ratio, it becomes suitable as a calcium-based admixture for use in a hydraulic composition. Furthermore, a hydraulic composition obtained by mixing the calcium-based admixture with blast furnace slag fine powder can be used to fix rock wool.

[0018] The sprayed fireproof coating has a bulk density of 0.28 g / cm 3 The bulk density of the sprayed fireproof coating material is 0.28 g / cm 3By setting the bulk density to 0.29 g / cm or more, the fire resistance performance of the sprayed fire-resistant coating material is improved. From the viewpoint of improving the fire resistance performance of the sprayed fire-resistant coating material, the bulk density of the sprayed fire-resistant coating material is preferably 0.29 g / cm 3 More than 0.35g / cm 3 The following is the result.

[0019] The sprayed fire-resistant coating material has a slurry concentration of 33% by mass or more and 43% by mass or less. A slurry is a fluid in which solid particles are suspended in a liquid, and in this embodiment, it is a fluid in which rock wool and a hydraulic composition are suspended in water. The slurry concentration is the total mass of the rock wool and the hydraulic composition relative to the volume of water. By setting the slurry concentration within this range, it becomes easier to spray the sprayed fire-resistant coating material onto the target object using conventional spraying equipment for sprayed rock wool, and it also becomes easier to achieve the desired coating thickness of the sprayed fire-resistant coating material.

[0020] The spray fireproof coating material has a content of rock wool and a hydraulic composition in the following blending ratios (1) to (3) when the spray fireproof coating material is taken as 100 parts by mass: (1) 60 parts by mass of rock wool and 40 parts by mass of hydraulic composition (2) 40 parts by mass of rock wool and 60 parts by mass of hydraulic composition (3) Rock wool is more than 40 parts by mass but less than 60 parts by mass, and the hydraulic composition is the part by mass obtained by subtracting the part by mass of rock wool. It is preferable that either of the above is used.

[0021] The blending ratios of the above-mentioned (1) to (3) are the same as the blending ratios of rock wool and hydraulic composition in conventional sprayed rock wool. Therefore, the sprayed fire-resistant coating material can easily ensure a slurry concentration equivalent to that of conventional sprayed rock wool. This makes it easy to achieve a predetermined coating thickness for the sprayed fire-resistant coating material using a spraying device for conventional sprayed rock wool.

[0022] As described above, the sprayed fire-resistant coating material of the embodiment can reduce carbon dioxide emissions resulting from cement production without reducing fire resistance compared to conventional sprayed rock wool. Therefore, an environmentally friendly sprayed fire-resistant coating material can be realized. Furthermore, by using a hydraulic composition that does not contain any cement, the sprayed fire-resistant coating material of the embodiment can reduce carbon dioxide emissions generated during material production by approximately 80% compared to conventional sprayed rock wool that uses a hydraulic composition containing cement as a main component. [Example]

[0023] Examples are described below. The dimensions, materials, shapes, relative positions, etc. of the components described in the examples are not intended to be limiting, but are merely examples, unless otherwise specified. Note that the size and positional relationship of components shown in each drawing may be exaggerated or simplified for clarity of explanation. Also, some elements may be omitted to avoid overly complicated drawings.

[0024] In this example, we investigated the fire resistance of steel members coated with a sprayed fire-resistant coating material that uses no cement at all, but a hydraulic composition that uses blast furnace slag, an industrial by-product, instead of cement (hereinafter referred to as "cement-free material"), i.e., environmentally friendly sprayed rock wool (hereinafter referred to as "environmentally friendly sprayed RW"). The cement-free material is defined as a material that contains 70 to 80 parts by mass of finely powdered blast furnace slag and 20 to 30 parts by mass of calcium-based admixture, when the cement-free material is taken as 100 parts by mass. For example, the cement-free material has a density of 0.432 ton / m 3 The mixture is made up of 0 parts by mass of Portland cement, 77.2 parts by mass of ground blast furnace slag, and 22.82 parts by mass of calcium-based admixture. The calcium-based admixture is made up of 31 parts by mass of expansive material, 37 parts by mass of limestone powder, and 32 parts by mass of slaked lime per 100 parts by mass of the calcium-based admixture.

[0025] 1. Experimental plan and temperature history of steel beams (steel materials) 1-1. Test plan 1-1-1. Test specimen A list of the test specimens is shown in Table 1. The test specimens are broadly divided into Case 1 (Nos. 1 to 3), in which the specimens were heated until collapse, and Case 2 (Nos. 4 and 5), in which the heating was stopped after 1 hour of heating. Three specimens were used for Case 1. The test variables were the mass ratio of rock wool to cement-free materials and the coating thickness of the environmentally friendly sprayed RW (sprayed RW thickness). The specimen conditions are shown in Table 1. The specimen configuration is shown in Figures 1A and 1B. Specimen 100 includes a steel beam 10, an environmentally friendly sprayed RW 20, and an ALC panel 30. The steel beam 10 measures H-400 x 200 x 8 x 13 x 8000 mm and is made of SN490 steel. The support section (support span) was 6800 mm, and the heating section was 6000 mm. In Figure 1A, P / 2 indicates the loading position in the load heating test, and the heating range HR indicates the area heated in the load heating test. In Figure 1B, the thickness of the environmentally friendly sprayed RW 20 is t (mm). The thickness of the ALC panel 30 is 100 mm.

[0026] Case 2 consisted of two test specimens under the same conditions. The purpose of Case 2 was to confirm whether the environmentally friendly sprayed RW would crack or fall off when left to cool. The steel beams were H-396 x 199 x 7 x 11 x 6000 mm, the support section (support span) was 5100 mm, and the heating section was 4200 mm. The conditions of the test specimens are as shown in Table 2. As with Case 1, in the loaded heating test, the loading position was on the trisecting line of the support section, and temperature measurement positions were at two cross sections. All other specifications were the same as those of the test specimens in Case 1.

[0027] [Table 1]

[0028] 1-1-2. Load heating and measurement method The loaded heating test for Case 1 was conducted according to the standard heating curve of ISO 834. Heating was continued until the critical deflection (289 mm) or critical deflection rate (12.84 mm / min) specified in the ISO was reached, or until the load-bearing capacity was lost. Figure 2 shows the setup for the loaded heating test. For the loaded heating test, a 20 MN loaded heating device 200 owned by Taisei Corporation was used. The load was a concentrated load of a specified load P (215 kN in Case 1 and 251 kN in Case 2) to generate the long-term allowable stress on the bottom flange of the steel beam. The test specimen was simply supported, and the loading position was on the trisecting line of the support section. For Case 2, heating was completed after one hour, and the specimen was allowed to cool for three hours while the specified load was still applied.

[0029] The temperature measurement locations (thermocouple installation locations) are shown in Figures 1C and 1D, and the displacement measurement locations are shown in Figure 1E. The temperature measurement cross sections were 1,225 mm away from the support (cross section of line ID-ID in Figure 1A: cross section ii) and 3,400 mm away (cross section of line IC-IC in Figure 1A: cross section i). There were five measurement points at each cross section: four at the top flange and bottom flange, and one at the web. There were eight displacement measurement points: two at the support of the specimen, four at the loading position, and two at the center of the beam.

[0030] 1-2. Experimental results - Temperature history Figure 3 shows a comparison of the maximum temperature history of the steel beams in specimens No. 1 to No. 5. The maximum temperatures of No. 4 and No. 5 were approximately 450°C and 500°C, respectively, showing a difference of approximately 50°C, but there was no difference in the temperature of the steel beams after 100°C, confirming reproducibility. Figure 4 shows a comparison of the temperature history of the steel beams in specimens No. 1 and No. 4. In Figure 4, the "No. 1-T1" graph corresponds to the temperature measurement location "T1" shown in Figure 1C for specimen No. 1. Similarly, the other graphs correspond to the temperature measurement locations shown in Figures 1C and 1D for specimens No. 1 and No. 4. Furthermore, the No. 1-calculated value and No. 4-calculated value graphs show the calculation results for the thermal properties of sprayed RW, using the Fire Resistance Design Guidelines for Steel Structures (Architectural Institute of Japan: Fire Resistance Design Guidelines for Steel Structures, March 2008).

[0031] For No. 1, at 72 minutes, the temperature of the top flange (measured at temperature locations T1, T2, T6, and T7 in Figures 1C and 1D) was 250°C, while the temperature of the bottom flange and web (measured at temperature locations T3, T4, T5, T8, T9, and T10 in Figures 1C and 1D) was 430°C. Comparing the calculated and experimental values ​​for No. 1, the experimental results were lower, approximately 60°C lower at 60 minutes after heating. For No. 4, for example, at No. 4-T5, the temperature was approximately 450°C at 60 minutes after heating, with a maximum temperature of 480°C (66 minutes after heating). The calculated results for No. 4 closely correlated with the experimental results up to 60 minutes after heating. Although direct comparison of No. 1 and No. 4 is not possible due to differences in the dimensions of the steel beams, the top flange temperatures were nearly the same, while the web and bottom flange temperatures for No. 4 were higher, approximately 100°C higher at 60 minutes after heating.

[0032] 1-3. Summary The results of this experiment showed that no cracks or falling off were observed in the environmentally friendly sprayed RW during or after heating, and for Nos. 1 to 3, the temperature of the test specimens (steel beams) at 72 minutes was 420 to 570°C, and the temperature of the test specimens (steel beams) at the time of collapse was 625 to 640°C. In other words, it can be said that the sprayed fireproof coating material of the embodiment not only has excellent fire resistance performance, but also can reduce carbon dioxide emissions caused by cement production.

[0033] 2. Deflection behavior during fire Deflection was evaluated by subtracting the displacement at the support point from the central displacement. 2-1. Experimental results 2-1-1. Condition of the test specimen after the experiment Figures 5A-5C show the condition of specimens No. 1 and No. 4 after the heating test. Figure 5A shows the condition of specimen No. 1 after the test, Figure 5B shows the condition of specimen No. 4 after the test, and Figure 5C shows the condition of the steel beam of specimen No. 1 after the test. No cracks or shedding of the environmentally friendly sprayed RW occurred in specimens No. 1-3 until the time of collapse, and in specimens No. 4 and No. 5 until three hours after heating and cooling. The environmentally friendly sprayed RW was removed from specimens No. 1-3 that collapsed. As an example, Figure 5C shows the condition of the steel beam (No. 1) after the test. No local buckling was observed in the center of the specimen or the steel beam directly below the load. Considering the condition of the steel beam and the deflection of the specimens after the test, it is believed that specimens No. 1-3 all collapsed in bending.

[0034] 2-1-2. Deflection behavior Table 2 shows the deflection and collapse time at 72 minutes for No. 1 to No. 3. In this experiment, the collapse time was defined as the point at which the applied load dropped by 10% compared to the target load. The deflection at 72 minutes was 142 mm for No. 3, and 66 to 69 mm for No. 1 and No. 2. No. 3 showed approximately twice the deflection of No. 1 and No. 2.

[0035] [Table 2]

[0036] Figure 6 shows an example of the overall measurement results, showing the relationship between deflection (displacement) and time for No. 1, and Figure 7 shows the deflection (displacement) distribution. In Figure 6, the start of heating is set to 0, and deflection toward the heating furnace is displayed as a positive value. The deflection of D3, measured at the center of the beam, was the largest, reaching 234 mm at the time of collapse (92 minutes after heating began). The deflection increased significantly between 82 and 92 minutes after heating began. The bottom flange temperature of the steel beam at this time was approximately 500°C. The deflection rate also increased sharply after 80 minutes of heating, reaching the critical deflection rate (12.84 mm / min) at 85 minutes. The deflection rate also increased to 2.5 mm / min between 40 and 60 minutes after heating began, and then plateaued. Figure 7 shows that the load was evenly distributed until collapse.

[0037] Figure 8 shows the relationship between vertical deflection (displacement) and time for No. 4. 60 minutes after the start of heating, the deflection at the center of the specimen was approximately 30 mm. The deflection peaked at 36.1 mm approximately 30 minutes after the end of heating (90 minutes after the start of heating). Figure 9 shows the deflection (displacement) distribution for No. 4. The load was evenly distributed on both sides until the end of the test, and the maximum residual deflection of the specimen after four hours of cooling was 21 mm. The deflection rate began to increase immediately after heating began, reaching a maximum of 1.25 mm / min. As this was smaller than the critical deflection rate, it was found to have a one-hour fire resistance.

[0038] Figure 10 shows a comparison of the beam center deflection (displacement) versus time for Nos. 1 to 5. The deflection here is the average of the values ​​measured in the east-west (E, W) directions. Comparing Nos. 1 to 3, which differ in the blend ratio and coating thickness of the cement-free raffinate, No. 3 showed the fastest increase in deflection and the shortest collapse time at 77 minutes. Comparing Nos. 1 and 2, which differ only in the blend ratio of the cement-free raffinate, showed similar deflection behavior up to 40 minutes after the start of heating. However, after 40 minutes, No. 1's deflection increased compared to No. 2, and it collapsed faster. Furthermore, even if the bulk density of the sprayed RW was increased compared to No. 1 (25 mm coating thickness), No. 3, with a coating thickness of 20 mm, showed a shorter collapse time than No. 1. These results suggest that even if the absolute amount of cement-free raffinate in the sprayed RW is increased, fire resistance will not be fully realized unless an appropriate spraying thickness is ensured. No. 4 and No. 5 showed similar deflection behavior, confirming reproducibility under the same conditions. Comparing No. 1 and No. 4, which have the same mass ratio of cement-free material to rock wool, the deflection of No. 1 after 60 minutes of heating was 1.6 times that of No. 4.

[0039] Figure 11 shows a comparison of deflection (displacement) rates for No. 1 to No. 5. The maximum deflection rate in Case 2 (No. 4, No. 5) was 0.17 times the maximum allowable deflection rate. In Case 1 (No. 1 to No. 3), where loading was continued until collapse, the load was supported even when the critical deflection rate was exceeded. In Case 1, the time at which the deflection rate began to increase rapidly was approximately 80 minutes for No. 1, approximately 90 minutes for No. 2, and approximately 60 minutes for No. 3. The steel beam temperature at that time was approximately the same for No. 1 to No. 3, at approximately 500°C.

[0040] 2-2. Summary The results of this experiment confirmed that the environmentally friendly sprayed RW coating with a thickness of 25 mm provides a fire resistance of 1 hour. In other words, the sprayed fireproof coating material of the embodiment not only has excellent fire resistance but also can reduce carbon dioxide emissions caused by cement production. [Explanation of symbols]

[0041] 10 Steel beams 20 Environmentally friendly sprayed RW 30 ALC panels 100 test specimens 200 20MN loading heating device

Claims

1. A spray-applied fireproof coating material in which rock wool and a hydraulic composition are mixed, The hydraulic composition contains 70 parts by mass or more and 80 parts by mass or less of ground blast furnace slag powder and 20 parts by mass or more and 30 parts by mass or less of a calcium-based admixture when the hydraulic composition is taken as 100 parts by mass, A spray-applied fire-resistant coating material characterized in that the moisture content of the spray-applied fire-resistant coating material is 2.0 mass% or more and 4.3 mass% or less.

2. When the sprayed fire-resistant coating material is taken as 100 parts by mass, the contents of the rock wool and the hydraulic composition are in the following blending ratios (1) to (3): (1) 60 parts by mass of the rock wool and 40 parts by mass of the hydraulic composition (2) 40 parts by mass of the rock wool and 60 parts by mass of the hydraulic composition (3) The rock wool is more than 40 parts by mass but less than 60 parts by mass, and the hydraulic composition is the part by mass obtained by subtracting the part by mass of the rock wool.

2. The spray-applied fire-resistant coating material according to claim 1, wherein the spray-applied fire-resistant coating material is any one of the following:

3. 3. The spray-applied fire-resistant coating material according to claim 1, wherein the hydraulic composition does not contain cement.

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