Covering structure

A coated steel beam structure with varying thickness coating layers enhances heat resistance and maintains pipe insertion ease, addressing the need for fire-resistant steel beams with unobstructed pipe access.

JP7876922B1Active Publication Date: 2026-06-22CO LTD アトムラ IND

Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
CO LTD アトムラ IND
Filing Date
2025-12-09
Publication Date
2026-06-22

AI Technical Summary

Technical Problem

Existing steel beams lack sufficient heat resistance during fires, and existing methods to enhance heat resistance compromise the ease of inserting pipes through insertion holes.

Method used

A coated structure for steel beams featuring a continuous coating layer made of refractory material covering the flanges, web, and insertion hole surfaces, with varying thicknesses to maintain pipe insertion ease and enhance heat resistance.

Benefits of technology

The coating structure provides high heat resistance to steel beams while allowing easy insertion of pipes, ensuring fire protection without reducing the hole diameter.

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Abstract

To provide a covering structure with high heat resistance for steel beams. [Solution] The steel beam 10 has a pair of flanges 20 and a web 30 that is continuous with the pair of flanges 20 and has through holes 32 through which pipes 210 are inserted. The steel beam 10 has a pair of flanges 20 and a web 30 that is continuous with the pair of flanges 20 and has through holes 32 formed therein. The steel beam 10 has a pair of flanges 20 and a web 30 that is continuous with the pair of flanges 20 and the web 30 and has through holes 32 and has an inner circumferential surface 33. The thickness T52 of the second coating layer 52 is smaller than the thickness T51 of the first coating layer 51. The steel beam 10 has a pair of flanges 20 and a web 30 that is continuous with the pair of flanges 20 and has through holes 32 through which pipes 210 are inserted. The steel beam 10 has a pair of flanges 20 and a web 30 that is continuous with the pair of flanges 20 and has through holes 32 through which pipes 210 are inserted. The thickness T60 of the surface layer 60 is smaller than the thickness T52 of the second coating layer 52. Furthermore, it is equipped with a pin 40 that protrudes from the inner circumferential surface 33 and has a length L42 equal to the thickness T52 of the second coating layer 52.
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Description

Technical Field

[0001] The present invention relates to a coated structure.

Background Art

[0002] Conventionally, it has been proposed to form insertion holes through which pipes are inserted in the web of a steel beam (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, in the steel beam of Patent Document 1, it is desired to enhance heat resistance in case of a fire.

[0005] Therefore, an object of the present invention is to provide a coated structure having high heat resistance for a steel beam.

Means for Solving the Problems

[0006] As means for solving the above problems, the present invention includes a steel beam having a pair of flanges and a web continuous with the pair of flanges and having insertion holes through which pipes are inserted, and a coating layer that continuously covers the surfaces of the flanges, the surface of the web, and the inner peripheral surface of the insertion holes and is formed of the same material and has heat insulation properties. The coating layer includes a first coating layer that covers the surfaces of the flanges and the web, and a second coating layer that covers the inner peripheral surface of the insertion holes. The thickness of the second coating layer is smaller than the thickness of the first coating layer, and a surface layer that covers the first coating layer and the second coating layer is provided. The thickness of the surface layer is smaller than the thickness of the second coating layer. The pins protrude from the inner circumferential surface and have a length equal to the thickness of the second coating layer. The coated structure is characterized by the above.

[0007] With this configuration, a coating layer made of the same material and possessing thermal insulation properties continuously covers the surface of the flange, the surface of the web, and the inner circumferential surface of the through-hole, thereby increasing the heat resistance of the flange and web, i.e., the steel beam.

[0008] Furthermore, piping can be inserted through the through-holes in the web. Here, since the thickness of the second coating layer covering the inner circumferential surface of the through-hole is smaller than the thickness of the first coating layer covering the surface of the flange and the surface of the web, the inner diameter of the through-hole through which the piping is inserted does not become significantly smaller, making it easier to insert the piping through the through-hole.

[0009] With this configuration, the surface layer protects the first coating layer by covering it.

[0011] With this configuration, the thickness of the second coating layer can be confirmed by the pin. That is, for example, if the tip of the pin and the surface of the second coating layer are approximately flush, it can be confirmed that the second coating layer is of a predetermined thickness. Furthermore, when applying the coating layer by spraying, the thickness of the second coating layer can be confirmed by the pin while spraying. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a covering structure for steel beams that has high heat resistance. [Brief explanation of the drawing]

[0013] [Figure 1] This is a perspective view of the covering structure according to this embodiment. [Figure 2] This is a cross-sectional view of the covering structure according to this embodiment. [Figure 3] This is a side view of the pin according to this embodiment. [Modes for carrying out the invention]

[0014] <<Structure of the covering structure>> One embodiment of the present invention will be described with reference to Figures 1 to 3. Here, as shown in Figure 1, for convenience, we define front, back, left, right, up, and down. The front-to-back direction (first horizontal direction) is the longitudinal direction of the steel beam 10. The left-to-right direction (second horizontal direction) is the horizontal direction and is perpendicular to the front-to-back direction (first horizontal direction).

[0015] The covering structure 1 comprises a steel beam 10, a pin 40, a covering layer 50, and a surface layer 60.

[0016] <Steel beam> The steel beam 10 is a metal member extending in the front-rear direction, with both ends fixed to columns (not shown), and supports the floor plate 110 from below. The steel beam 10 is, for example, H-shaped or I-shaped, and comprises a pair of flanges 20, 20 and a web 30 continuous with the pair of flanges 20, 20.

[0017] The pair of flanges 20, 20 are positioned at the upper and lower parts of the steel beam 10 in the longitudinal section, and are elongated plate-like portions that are wide in the left-right direction and extend in the front-back direction.

[0018] The web 30 is a plate-like portion that is wide in the vertical direction and extends in the front-to-back direction in a longitudinal cross-section. The upper part of the web 30 is joined to the upper flange 20, and the lower part of the web 30 is joined to the lower flange 20.

[0019] The web 30 has a plurality of through holes 32. The plurality of through holes 32 are arranged at intermediate positions in the vertical (height) direction and at predetermined intervals in the front-to-back direction. The through holes 32 are through holes that penetrate the web 30 in the thickness direction and are holes for inserting cylindrical pipes 210 (ducts). Electrical wiring, for example, is provided inside the pipes 210. Alternatively, a ring-shaped reinforcing member that reinforces the web 30 may be joined to one or both sides of the opening edge of the through hole 32. In addition, a reinforcing plate with through holes of the same diameter as the through holes 32 may be joined to one or both sides of the web 30.

[0020] <Pin> Pin 40 is a member provided on the inner peripheral surface 33 of the insertion hole 32 and protruding radially inward, and includes a pedestal 41 and a pin body 42 extending from the pedestal 41. A plurality of pins 40 are provided on the inner peripheral surface 33 at predetermined intervals (90° intervals in this embodiment) in the circumferential direction.

[0021] The pedestal 41 is a portion fixed to the inner peripheral surface 33 and is arc-shaped in a cross-sectional view corresponding to the inner peripheral surface 33. The pedestal 41 of the pedestal is fixed to the inner peripheral surface 33 with, for example, a double-sided tape or an adhesive.

[0022] The pin body 42 is a needle-shaped (elongated columnar) member extending radially inward from the pedestal 41. The length L42 from the pedestal 41 to the tip 42a of the pin body 42 (the length of the pin 40) is substantially equal to the thickness T52 of the second coating layer 52 to be described later (L42 = T52). Thus, the thickness T52 of the second coating layer 52 can be confirmed by the pin body 42. That is, when the tip 42a of the pin body 42 and the surface 52a of the second coating layer 52 are substantially flush, it can be confirmed that the second coating layer 52 has a generally predetermined thickness. Also, when the coating layer 50 is applied by spraying, it can be sprayed while confirming the thickness D52 of the second coating layer 52 by the pin 40.

[0023] <Coating layer> The coating layer 50 is a layer that continuously coats the surface 21 of the flange 20, the surface of the web 30, and the inner peripheral surface 33 of the insertion hole 32. "Continuously coating" means that the first coating layer 51 and the second coating layer 52 to be described later are applied in the same material and in the same process, and joints and the like are not formed and are continuously coated without interruption.

[0024] The coating layer 50 is a refractory layer (heat insulation layer) having fire resistance (heat insulation). Thus, for example, even if a fire breaks out indoors, the heat of the fire is insulated by the coating layer 50, and the steel girder 10 is protected from the heat. The coating layer 50 is formed, for example, by spraying a mixture of rock wool (artificial mineral fiber) and cement (hardening material) slurry with a spraying gun while mixing and then curing it. The density of the coating layer 50 is, in the absolutely dry state, for example, 0.25 to 0.80 (g / cm ).

[0025] The coating layer 50 includes a first coating layer 51 and a second coating layer 52.

[0026] The first coating layer 51 is a layer that covers the surface 21 of the flange 20 and the surface 31 of the web 30. The thickness T51 of the first coating layer 51 is, for example, 45 to 60 mm.

[0027] The second coating layer 52 is a layer that covers the inner peripheral surface 33 of the insertion hole 32. The thickness T52 of the second coating layer 52 is, for example, 15 to 20 mm. That is, the thickness T52 of the second coating layer 52 is smaller than the thickness T51 of the first coating layer 51 (T52 < T51) and is approximately 1 / 2 to 1 / 3.

[0028] <Surface layer> The surface layer 60 is an extremely thin finishing layer that covers the coating layer 50 (the first coating layer 51 and the second coating layer 52). Thus, the surface layer 60 protects the coating layer 50.

[0029] The thickness T60 of the surface layer 60 is smaller than the thickness T52 of the second coating layer 52 (T60 < T52) and is, for example, 2 to 5 mm. The surface layer 60 is an extremely thin cement layer formed, for example, by spraying cement slurry. In addition, the surface layer 60 can also be formed with a coating film of a desired color by applying a paint of the desired color to enhance the design.

[0030] ≪Function and effect of the coating structure≫ Next, the function and effect of the coating structure 1 will be described. Since the insulating coating layers 50 (first coating layer 51, second coating layer 52) formed from the same material continuously cover the surface 21 of the flange 20, the surface 31 of the web 30, and the inner circumferential surface 33 of the insertion hole 32, the heat resistance of the flange 20 and the web 30, that is, the steel beam 10, is increased.

[0031] Since the thickness T52 of the second coating layer 52 covering the inner circumferential surface 33 of the insertion hole 32 is smaller than the thickness T51 of the first coating layer 51 covering the surface 21 of the flange 20 and the surface 31 of the web 30, the inner diameter of the insertion hole 32 through which the pipe 210 is inserted is not significantly reduced, and the pipe 210 can be easily inserted into the insertion hole 32.

[0032] ≪Construction Method for Covering Structures≫ Next, we will explain one method of constructing the covering structure 1. Rock wool and cement slurry are sprayed using a spray gun onto the surface 21 of the flange 20, the surface 31 of the web 30, and the inner circumferential surface 33 of the insertion hole 32 to form a coating layer 50 (first coating layer 51, second coating layer 52). In this case, for example, the second coating layer 52 and the first coating layer 51 are formed continuously. The amount of spraying is also adjusted so that the surface 52a of the second coating layer 52 is flush with the tip 42a of the pin body 42.

[0033] Subsequently, cement slurry is sprayed in a predetermined amount to form the surface layer 60. As a result, a covered structure 1 is obtained.

[0034] ≪Variations≫ Although one embodiment of the present invention has been described above, the present invention is not limited thereto and may be modified as follows, for example.

[0035] In the above-described embodiment, a configuration in which the covering structure 1 includes a surface layer 60 was illustrated, but other configurations, such as one without a surface layer 60, are also possible.

[0036] In the embodiment described above, a configuration in which the surface layer 60 covers the first coating layer 51 and the second coating layer 52 was illustrated. However, for example, the surface layer 60 may cover only the first coating layer 51 and not the second coating layer 52. With such a configuration, since the surface layer 60 is not provided on the radially inner side of the second coating layer 52, the inner diameter of the insertion hole 32 is not reduced by the surface layer 60. [Explanation of symbols]

[0037] 1. Covering structure 10 Steel beams 20 flanges 21 Surface 30 Web 31 Surface 32 Through hole 33 Inner peripheral surface 40 pins 41 Pedestal 42-pin body 50 Covering layer 51 1st coating layer 52 Second coating layer 60 Surface layer (surface layer) 110 Floorboards 210 Piping L42 Pin Length T51 Thickness of the first coating layer T52 Thickness of the second coating layer T60 Surface thickness

Claims

[Claim 1] A steel beam having a pair of flanges and a web that is continuous with the pair of flanges and has through holes through which pipes are inserted, A coating layer is formed from the same material and has heat-insulating properties, which continuously covers the surface of the flange, the surface of the web, and the inner circumferential surface of the insertion hole. Equipped with, The coating layer comprises a first coating layer that covers the surface of the flange and the surface of the web, and a second coating layer that covers the inner circumferential surface of the through hole. The thickness of the second coating layer is smaller than the thickness of the first coating layer. The device comprises a surface layer covering the first coating layer and the second coating layer, The thickness of the surface layer is smaller than the thickness of the second coating layer. The pins protrude from the inner circumferential surface and have a length equal to the thickness of the second coating layer. A covering structure characterized by the following: