JP7499072B2 - Method for installing fireproof member and fireproof member - Google Patents

Description

The present invention relates to a method for constructing a fire-resistant component and a fire-resistant component, and in particular to a method for constructing a fire-resistant component by applying fire-resistant paint in succession, and a fire-resistant component.

Traditionally, when a structure made of steel, such as a steel building, is exposed to fire, the temperature rise in the steel reduces its strength and rigidity, and there is a risk that the structure will collapse. For this reason, fire-resistant coatings are applied to the beams and columns of steel-framed structures to prevent temperature increases caused by fire.

One type of fire-resistant coating material is a fire-resistant paint whose main component is ammonium polyphosphate. When exposed to heat during a fire, fire-resistant paint begins to foam at around 250°C, expanding 20 to 30 times in size to form an insulating layer and suppress the temperature rise of the steel material. Fire-resistant paint is applied to the surface of the steel material in a thickness ranging from a few millimeters to a dozen millimeters.

When fire-resistant paint is applied to steel members in a factory such as a steel frame prefabricator, and then the members 1 are transported to the construction site and installed, as shown in Figure 5, and fire-resistant paint is applied on-site to the joints or around the joints 2, it is necessary to ensure the integrity of the fire-resistant paint 3 applied at the factory and the fire-resistant paint 4 applied on-site. In other words, if the integrity of the fire-resistant paint applied at the factory and the fire-resistant paint applied on-site cannot be ensured, there is a risk that the required insulation performance in the event of a fire cannot be ensured.

On the other hand, a technique for forming a cured film on a part where a fire-resistant cured film is lost for some reason after a fire-resistant cured film has already been formed on the surface of a substrate that forms a structure is known, for example as described in Patent Document 1. This technique involves a step of attaching a cured film made by curing a fire-resistant paint to an unformed part where a cured film of the fire-resistant paint is not formed via a primer layer before drying and curing, and a step of drying and curing the primer layer. This method involves cutting out the cured film of the fire-resistant paint to the required size and pasting it on the unformed part, which is problematic in that it is time-consuming and laborious.

JP 2014-105566 A

The present invention has been made in consideration of the above, and aims to provide a method for applying fire-resistant components and fire-resistant components that ensure the integrity of the fire-resistant paint and ensure fire resistance even when the fire-resistant paint is applied at a factory and then further applied on-site.

In order to solve the above problems and achieve the objectives, the method of constructing fire-resistant components according to the present invention is a method of constructing fire-resistant components by applying a foaming fire-resistant paint that foams at a predetermined foaming temperature when heated to a portion of the surface of a steel material, drying and hardening the paint, and then applying a new fire-resistant paint next to the dried and hardened fire-resistant paint, the method being characterized in that the fire-resistant paint is composed of a paint containing a polyether-based resin.

The fire-resistant component according to the present invention is a fire-resistant component comprising a steel material and a foaming fire-resistant paint that is applied to the surface of the steel material and foams at a predetermined foaming temperature when heated, and is characterized in that it comprises a fire-resistant paint applied to a portion of the surface of the steel material and a fire-resistant paint applied adjacent to the fire-resistant paint, and the fire-resistant paint is composed of a paint containing a polyether-based resin.

According to the method for constructing fire-resistant components of the present invention, a foaming fire-resistant paint that foams at a specified foaming temperature when heated is applied to a portion of the surface of the steel material, the paint is dried and hardened, and then a new fire-resistant paint is applied next to the dried and hardened fire-resistant paint to construct the fire-resistant component. Since the fire-resistant paint is composed of a paint containing a polyether resin, the integrity of the fire-resistant paint is ensured even if the fire-resistant paint is applied at the factory and then further applied on-site, and fire resistance is also ensured.

The fire-resistant component according to the present invention is a fire-resistant component comprising a steel material and a foaming fire-resistant paint that is applied to the surface of the steel material and foams at a predetermined foaming temperature when heated, and comprises a fire-resistant paint applied to a portion of the surface of the steel material and a fire-resistant paint applied next to the fire-resistant paint, and the fire-resistant paint is composed of a paint containing a polyether resin, so that the integrity of the fire-resistant paint is ensured even if the fire-resistant paint is applied at the factory and then further fire-resistant paint is applied on-site, and fire resistance is also ensured.

FIG. 1(1) is a cross-sectional view of a main part showing an embodiment of a fire-resistant component and a method for installing the fire-resistant component according to the present invention, and FIG. 1(2) is a modified example. FIG. 2 is a diagram showing materials used in the examples. FIG. 3 is a diagram showing the main material coating specifications of the fire-resistant paint joint, where (1) is a side view of the pre-coated area, (2) is a cross-sectional view along line A-A of (1), (3) is a side view of the post-coated area, and (4) is a cross-sectional view along line B-B of (3). FIG. 4 is a diagram showing the undercoat area of the fire-resistant paint joint, (1) being a side view, and (2) being a cross-sectional view taken along line A-A of (1). Figure 5 is an image of a steel frame structure that combines parts where fireproof paint was applied in a factory and parts where it was applied on-site.

Below, an embodiment of the fire-resistant member and the installation method of the fire-resistant member according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to this embodiment.

As shown in FIG. 1 (1), a fire-resistant member 10 according to an embodiment of the present invention comprises a steel plate 12 (steel material), a fire-resistant paint 14 that is applied in advance on one side of the surface of the steel plate 12 at a factory or the like, and a fire-resistant paint 16 that is applied next to the fire-resistant paint 14 at a construction site or the like. Both fire-resistant paints 14 and 16 are composed of strong solvent-based fire-resistant paints of the same components, including ammonium polyphosphate and polyether-based resin, and are applied to the surface of the steel plate 12 via a primer 18. When this fire-resistant paint is exposed to heat during a fire, it begins to foam at around 250°C (foaming temperature), foams 20 to 30 times, forms a heat-insulating layer, and suppresses the temperature rise of the steel plate 12.

For the interface between the pre-applied fireproof paint 14 and the post-applied fireproof paint 16, a method may be adopted in which a primer 18 is applied to the pre-applied area and the post-applied area, and then the fireproof paint 14 is applied to the pre-applied area. Also, as shown in Figure 1 (1), it is preferable to apply the fireproof paints 14 and 16 on the surface of the primer 18 to form a wedge-shaped layer whose film thickness changes linearly in cross-section, and to finish them to the same thickness, but the present invention is not limited to this. For example, as shown in Figure 1 (2), the fireproof paints 14 and 16 may be applied so that there is no overlapping portion.

In this embodiment, the fire-resistant paints 14 and 16 are strong solvent-based fire-resistant paints that use polyether resins, so even if the fire-resistant paint 14 is applied to the steel plate 12 at the factory and then the fire-resistant paint 16 is applied over it at the construction site, the integrity of the fire-resistant paints 14 and 16 is ensured, and fire resistance is also ensured.

In the above embodiment, the foaming temperature of the fire-resistant paint is around 250°C. However, the present invention is not limited to this and can be applied to fire-resistant paints with foaming temperatures other than this. In any case, any fire-resistant paint can be used as long as it is a strong solvent-based fire-resistant paint that uses a polyether resin. In this case, the same effects as those described above can be achieved.

(Example)
In order to verify the effect of the present invention, a fireproof paint precoated steel beam was manufactured as an example, and a fireproof test was conducted to confirm the fireproof performance. In this example, it was assumed that the fireproof paint would be used as a fireproof coating around the joints and joints after the steel beam precoated with the fireproof paint was erected at the construction site. The coverage area in the longitudinal direction of the steel material was divided into two, and the fireproof paint was applied to one coverage area, and then the fireproof paint was applied to the other coverage area. In the jointed area, a jointing method that is considered to be disadvantageous in terms of fireproofing was adopted. That is, as shown in Figure 1 (2), the first applied fireproof paint 14 and the second applied fireproof paint 16 were not applied over each other.

The specifications of the fireproof paint used are shown in Figure 2. The fireproof paint used was "Taitect (registered trademark)" (Kansai Paint Co., Ltd.). The amount of coating and the film thickness (wet) when coating the main material vary depending on various conditions, but the guidelines for the production of the test specimens this time (not including film thickness adjustment and loss) were coating amount: 2500 g/m ² , film thickness (wet): 2.00 mm, and film thickness (dry): 1.75 mm. Two cases of main material thickness were set according to the fireproof time: 1.75 mm (fireproof time 1 hour) and 4.80 mm (fireproof time 2 hours). The cross section of the steel material used was H-400 x 200 x 8 x 13 mm (H-shaped steel), and the steel type was SM490A of JIS G 3106 "Rolled steel material for welded structure". The total length of the fire-resistant paint precoated steel beam was 5,800 mm, and an ALC plate 100 mm thick and 600 mm wide was attached to the top of the steel beam with stud bolts to simulate a floor.

As shown in Figure 3, the application of fireproof paint to the joints was done in the following order: [primer coat on the previous application area and the later application area] → [main coat on the previous application area] → [leave for 24 hours] → [main coat on the later application area] → [intercoat on the previous application area and the later application area] → [topcoat on the previous application area and the later application area]. The primer is a weak solvent-based paint and the main paint is a strong solvent-based paint, so even if the primer is applied to the later application area first, the strong solvent of the main paint will melt the surface layer of the primer when the main paint is applied, ensuring adhesion of both paints.

In this example, the undercoat was applied in advance over the entire surface of the later application area, but in reality, the undercoat around the joints and joints will be applied later in order to perform bolt and weld joints. In practice, therefore, it is desirable to apply the undercoat of the later application area as far as possible (for example, L = 100 mm or more) beyond the end of the earlier application main material so that the paint film of the earlier application main material is not affected by rust on the steel frame base, as shown in Figure 4. Also, in the production of the example, the intermediate coat and top coat of the earlier application area and the later application area were applied simultaneously as shown in Figure 3, but the intermediate coat and top coat of the later application area may be applied after the intermediate coat and top coat of the earlier application area have been completed in the earlier application. In that case, it is desirable to apply the later application intermediate coat and top coat over the intermediate coat and top coat of the earlier application area.

Before applying the fireproof paint, the surface of the steel was prepared by blasting. The main material was applied with a trowel in several layers, and the thickness was adjusted by sanding the hardened paint film. The undercoat, intermediate coat, and top coat were applied with a roller. The procedure for applying the fireproof paint in the production of the example was to first apply the undercoat to the entire surface where the fireproof paint was to be applied, and then finish the main material in the first application area to the specified thickness. For the main material coating joint, a polypropylene resin board (a board made of a material that paint does not easily adhere to) made to match the specified main material thickness was placed as a ruler at the coating joint, and the main material was applied. After the coating of the main material in the first application area was completed, a day was left, and the main material in the second application area was coated with the specified thickness. Then, the top coat and intermediate coat were applied to complete the painting. Minor unevenness was observed in the fireproof paint coating joint, but no cracks or fissures occurred.

Fire resistance tests were conducted on the steel beams that had been precoated with fire-resistant paint in this way, and the temperature of the steel around the joints was closely measured. As a result of these measurements, it was confirmed that the required fire resistance performance (1-hour fire resistance, 2-hour fire resistance) had been secured.

As explained above, the method for constructing fire-resistant components according to the present invention involves applying a foaming fire-resistant paint that foams at a specified foaming temperature when heated to a portion of the surface of a steel material, drying and hardening the paint, and then applying a second coat of fire-resistant paint next to the dried and hardened fire-resistant paint to construct a fire-resistant component. Since the fire-resistant paint is made of a paint containing a polyether resin, the integrity of the fire-resistant paint is ensured even if the fire-resistant paint is applied at the factory and then further applied on-site, and fire resistance is also ensured.

The fire-resistant component according to the present invention comprises a steel material and a foaming fire-resistant paint that is applied to the surface of the steel material and foams at a predetermined foaming temperature when heated. The fire-resistant paint is applied to a portion of the surface of the steel material and is applied next to the fire-resistant paint. The fire-resistant paint is composed of a paint containing a polyether resin, so that the integrity of the fire-resistant paint is ensured even if the fire-resistant paint is applied at the factory and then further fire-resistant paint is applied on-site, and fire resistance is also ensured.

As described above, the fire-resistant component application method and fire-resistant component of the present invention are useful for fire-resistant components that are applied at a factory and then overcoated with fire-resistant paint on-site, and are particularly suitable for ensuring the integrity and fire resistance of the fire-resistant paint.

10 Fireproof member 12 Steel plate (steel material)
14, 16 Fireproof paint 18 Primer

Claims (2)

A method for constructing a fireproof member by applying a first fireproof paint, which foams at a predetermined foaming temperature when heated, to a part of the surface of a steel material, drying and hardening the first fireproof paint, and then applying a second fireproof paint next to the first fireproof paint that has dried and hardened,
The method includes the steps of: applying an undercoat material to a pre-application range and a post-application range set on the surface, and then applying the first fire-resistant paint on the undercoat material in the pre-application range; and drying and curing the first fire-resistant paint, and then applying the second fire-resistant paint on the undercoat material in the post-application range.
The method for applying a fire-resistant member is characterized in that the first fire-resistant paint and the second fire-resistant paint are composed of strong solvent-based paints having the same components , including ammonium polyphosphate and a polyether-based resin, and the undercoat material is composed of a weak solvent-based paint . A fireproof member comprising a steel material, an undercoat material provided on a surface of the steel material, and a foaming fireproof paint provided on the undercoat material and foaming at a predetermined foaming temperature by heating,
The fire-resistant paint comprises a first fire-resistant paint applied on a portion of the undercoat material, and a second fire-resistant paint applied by applying it over the undercoat material next to the first fire-resistant paint, the first fire-resistant paint and the second fire-resistant paint being composed of a strong solvent-based paint of the same components containing ammonium polyphosphate and a polyether-based resin , and the undercoat material being composed of a weak solvent-based paint, characterized in that the fire-resistant member.

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