JP7208044B2 - Seismic ceiling structure - Google Patents

Description

The present invention relates to an earthquake resistant ceiling structure.

2. Description of the Related Art Conventionally, suspended ceilings have been widely used as ceilings of buildings such as schools, hospitals, production facilities, gymnasiums, swimming pools, airport terminal buildings, office buildings, theaters, and cinema complexes. Such a suspended ceiling includes a plurality of ceiling joists arranged side by side with a predetermined interval in one horizontal direction, and a plurality of ceiling joists perpendicular to the ceiling joists and arranged side by side with a predetermined interval in the other horizontal direction. A plurality of joist receivers that are integrally connected to the joist, the lower end is connected to the joist receiver, and the upper end is fixed to the upper structure (building frame) such as the floor material on the upper floor It is composed of a plurality of suspension bolts (suspension members) and a ceiling panel that is integrally attached to the lower surface of the ceiling joist with screws or the like to form the ceiling surface of the lower floor.

On the other hand, the suspended ceiling, in which the ceiling base of the ceiling joists and ceiling joist receivers and the ceiling panel are suspended and supported by suspension members, is subject to horizontal acceleration during an earthquake and causes lateral vibration. Since the ceiling panel behaves structurally separately from the building frame and tends to amplify rolling, there is a risk that the ceiling panel will collide with the building frame, such as walls, pillars, and beams, and be damaged and fall off. rice field.

In order to prevent such a suspended ceiling from falling off, it is known to install diagonal members as earthquake-resistant members or to place walls, etc. that bear the seismic force around the ceiling as described in Notification No. 791 of the Ministry of Land, Infrastructure, Transport and Tourism. It is
As another example, for example, as shown in Patent Document 1, a substantially bar-shaped tension member is provided below the ceiling panel and in the lateral direction along the ceiling panel, and this tension member is attached to both ends of the building. The ceiling panel and the building frame are connected by connecting and arranging to the building frame, and by connecting and fixing the intermediate portion between both ends to the ceiling panel and/or the ceiling panel and/or the ceiling panel from below the ceiling panel and/or the ceiling panel by connecting and fixing means. There are also known earthquake-resistant ceiling structures in which the ceiling panels have improved earthquake-resistant performance, and straight ceilings in which the ceiling is directly attached to a trellis composed of columns and beams, although they are not suspended ceilings.

JP 2013-177801 A

A clean room that requires control of the amount of dust in the air has no clearance (hereinafter referred to as ceiling clearance) between walls, columns, beams, etc. around the ceiling and the members that make up the ceiling in order to ensure airtightness. is preferred. In addition, in clean rooms, interference with earthquake-resistant members is a problem because there are many facilities behind the ceiling.

In the method of installing diagonal members as earthquake-resistant members, the ceiling panel moves in sync with the upper structure from which it is suspended, and moves differently from the pillars and walls around the ceiling, creating a clearance around the ceiling that makes it difficult to maintain airtightness. In the case of the method of arranging walls, etc. that bear the seismic force around the ceiling, there is no clearance around the ceiling in daily life, but during an earthquake, the ceiling panel and the wall, etc. that bear the seismic force collide. The airtightness of the clean room is lost due to the presence of gaps.

If the ceiling is directly attached to the grape trellis or the tension member is placed on the lower surface of the ceiling panel to provide earthquake resistance, such as in Patent Document 1, airtightness can be easily maintained even in the event of an earthquake. However, in the case of a direct ceiling using a grape trellis, in addition to the problems of high cost and increased load, the height of the ceiling surface is lowered due to an increase in the ceiling height due to interference adjustment with the equipment in the ceiling. I had a problem with it.

In addition, if a tensile member is placed on the lower surface of the ceiling panel to provide earthquake resistance as in Patent Document 1, there is a problem with the required performance of a clean room that does not like unevenness of the ceiling surface from the viewpoint of dust adhesion prevention. However, due to the use of tension members, the arrangement of steel materials that connect the support points with straight lines is an essential configuration, and there is room for improvement in this respect.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an earthquake-resistant ceiling structure that can secure airtightness without installing diagonal members or tension members, eliminating the need for a ceiling clearance, and ensuring airtightness. With the goal.

In order to achieve the above object, the earthquake-resistant ceiling structure according to the present invention is a ceiling panel that is suspended and supported by the upper structure of a building frame via suspension members, and that forms a suspended ceiling without installing an earthquake-resistant member composed of diagonal members or tensile members. and a horizontal force transmission member connected to an upper surface of an end portion of the ceiling panel, wherein the end portion of the ceiling panel is connected to the building frame or a support structure portion of the building frame via the horizontal force transmission member. and the horizontal force transmission member is designed based on the maximum tension calculated from the following formula (1),
maxH=maxK×maxW×maxb×maxl (1)
Note that maxH is the maximum tension (N) of the horizontal force transmission member
maxK: Maximum design horizontal seismic coefficient
maxW: maximum design load of the ceiling (N/m ² )
maxb: Maximum installation interval of horizontal force transmission members (m)
maxl: Maximum distance between fulcrums of horizontal force transmission member (m)
It is characterized by

In the present invention, by joining the ends of the ceiling panel to the building frame near the height of the ceiling surface or the support structure provided on the building frame through the horizontal force transmission member, the ceiling panel with high in-plane rigidity can be manufactured. Using this characteristic, the horizontal inertial force of the ceiling that acts during an earthquake can be reliably transmitted to the building frame, or transmitted to the building frame via the support structure, and the ceiling can be integrated horizontally with the building frame. behave. That is, it is possible to suppress the amplification of the vibration of the ceiling and prevent the ceiling from colliding with the walls, pillars, beams, and other structures of the building as in the past.

In addition, in the present invention, as described above, since the ceiling part behaves in the horizontal direction integrally with the building frame or support structure near the height of the ceiling surface, which is less susceptible to inter-story displacement, airtightness can be ensured. Therefore, it is not necessary to provide a horizontal clearance between the ceiling surface and the building frame, and it can be applied to buildings such as clean rooms that require airtightness both in normal times and during earthquakes.
Furthermore, in the present invention, since no earthquake-resistant member is arranged other than the horizontal force transmission member provided at the end of the ceiling panel, the degree of freedom in facility arrangement is secured, and the design is not degraded. .

Further, in the earthquake-resistant ceiling structure according to the present invention, the support structure section is a support beam installed between columns of the building frame, and the horizontal force transmission member and the support beam are provided between the horizontal force transmission member and the support beam. A height adjustment member that can be fixed by adjusting a vertical interval between the force transmission member and the support beam may be provided.

In this case, it is possible to dispose the height adjusting member having a dimension that matches the vertical gap between the ceiling panel and the beam, thereby facilitating the joining of the ceiling panel and the beam.

According to the earthquake-resistant ceiling structure of the present invention, it is possible to secure airtightness without installing diagonal members or tensile members, eliminating the need for a ceiling clearance.

1 is a perspective view showing a seismic ceiling structure according to an embodiment of the present invention; FIG. FIG. 2 is a side cross-sectional view of the earthquake-resistant ceiling structure shown in FIG. 1 viewed from a second lateral direction; FIG. 3 is a side cross-sectional view showing a main part of a joint portion between a ceiling panel and a support beam via a horizontal force transmission member in the earthquake-resistant ceiling structure shown in FIG. 2 ; FIG. 2 is a top plan view of one section of the earthquake-resistant ceiling structure shown in FIG. 1 ;

Hereinafter, an earthquake-resistant ceiling structure according to an embodiment of the present invention will be described based on the drawings.

As shown in FIGS. 1 and 2, the earthquake-resistant ceiling structure 1 according to the present embodiment is used in the ceilings of buildings such as clean rooms, production factories, research facilities, etc., where the ceiling must be airtight. This earthquake-resistant ceiling structure 1 is applied not only to new buildings but also to repair work for making existing buildings earthquake-resistant.

The earthquake-resistant ceiling structure 1 includes a joist receiver 2 that is suspended and supported by a superstructure 11 such as a slab of a building frame via a suspension member 6, a joist 3 attached to the joist receiver 2, and a lower surface of the joist 3. A horizontal force transmission member 5 that joins the ceiling panel 4 attached to the ceiling panel 4, the upper surface 4b at the end 4c of the ceiling panel 4, and the support structure (beam 13 described later) provided in the building frame. there is

The joist 3 is, for example, a thin sheet steel specified in JIS A 6517, is horizontally extended, and is positioned at a predetermined interval in the first horizontal direction X1 in one horizontal direction (horizontal direction of the paper surface in FIGS. 1 and 2) are arranged in parallel with a space between them.

The joist receiver 2 is, for example, a thin plate steel specified in JIS A 6517, extends horizontally along the first horizontal direction X1, and extends in the other horizontal direction at right angles to the first horizontal direction X1. A plurality of them are arranged in parallel with a predetermined interval in the direction X2 (the direction perpendicular to the plane of FIG. 2). The joist receiver 2 is arranged so as to intersect with the joists 3 and is arranged in a state of being placed on the plurality of joists 3. - 特許庁Each joist receiver 2 is connected to the joist 3 by using a joist connection fitting (hereinafter referred to as a clip 22) at a portion where it intersects with the joist 3.

The suspending member 6 is a suspending bolt formed in the shape of a cylindrical bar and having a male screw thread on the outer peripheral surface, and the upper end is fixed to the upper structure 11 such as the floor material of the upper floor, or is tightly connected to a steel joist or the like. The lower end side is connected to the joist receiver 2 by using a hanger 60 which is a fitting for connecting a hanging member, and a plurality of them are arranged. Also, the plurality of hanging members 6 are distributed at predetermined intervals.

As shown in FIG. 3, the ceiling panel 4 is formed by laminating ^two boards, for example, together. formed. The ceiling panel 4 is installed by being screwed to the lower surfaces 3a of the plurality of joists 3 with screws 41 (see FIG. 2). The ceiling panel 4 may be composed of one board or three or more boards.

Thus, in the earthquake-resistant ceiling structure 1 , the ceiling joist 3 , the ceiling joist receiver 2 , and the ceiling panel 4 are suspended from the upper structure 11 via the hanging members 6 . A ceiling base is formed by the joist 3 and the joist receiver 2, and a ceiling part is formed by the ceiling panel 4 attached to the ceiling base. A ceiling surface 4a is formed by the ceiling portion.

As shown in FIGS. 3 and 4 , the ceiling panel 4 extends below a support beam 13 to be described later, and is joined to the lower end 13 a of the support beam 13 (support structure) via a horizontal force transmission member 5 . ing.

The ceiling panel 4 configured in this way propagates the horizontal inertial force acting on the ceiling surface constituent members (the ceiling joists 2, the joists 3, and the ceiling panel 4) to the support structure (the beams 13) during an earthquake. functioning as components.

As shown in FIGS. 1 and 2, the building skeleton 10 is a main structural part of a building such as walls, pillars, beams, and floors. As a support structure provided in the building frame 10, there are supporting beams 13 which are integrally joined so as to extend adjacent columns 12, 12 in the horizontal direction and arranged at a predetermined height.

A plurality of columns 12 may be provided at predetermined intervals in the first horizontal direction X1 and the second horizontal direction X2. For example, the span of the pillar 12 can be set to 10 m or more×10 m or more.

As shown in FIG. 2, the support beams 13 support the horizontal inertial force generated in the ceiling surface constituent members (roofing receivers 2, 3, ceiling panel 4) during an earthquake, and horizontally between the columns 12, 12. placed. A plurality of receiving beams 13 are provided so as to extend along the first lateral direction X1 and the second lateral direction X2 parallel to the joist 3 and the joist receiver 2 (see FIG. 4). On both sides of the web 13A of the receiving beam 13, reinforcing ribs 131 whose plane faces the direction orthogonal to the beam length direction are joined at intervals in the length direction.
Further, the receiving beam 13 is suspended and supported by hanging members 132 supported from the upper structure at predetermined intervals in the beam length direction. By providing the suspending member 132, it is possible to prevent the support beam 13 from bending due to its own weight.

As the columns 12 and the support beams 13, for example, shaped steel such as H-shaped steel, I-shaped steel, and channel steel, tubular materials such as square steel pipes, and reinforced concrete structures can be used. H-shaped steel is adopted for the support beam 13 of the present embodiment, and for example, H-500×200×10×16 are arranged sideways (web 13A is sideways).

As shown in FIG. 3, the horizontal force transmission member 5 is a steel material having an L-shaped cross section. A vertical plate 52 is fixed to the height adjusting member 7 with a plurality of screws 71 .

The height adjustment member 7 is provided between the horizontal force transmission member 5 and the support beam 13 so as to be fixed by adjusting the vertical interval between the horizontal force transmission member 5 and the support beam 13 . The height adjustment member 7 is a rectangular steel plate, and has a bolt hole formed in the upper portion thereof, and is fixed to the lower reinforcing rib 131 of the support beam 13 by fastening a bolt 72 using the bolt hole. . A lower portion of the height adjustment member 7 is fixed to the vertical plate 52 of the horizontal force transmission member 5 with a plurality of screws 71 .

The height adjustment member 7 configured in this manner is fixed to the ceiling panel 4 and the beams 13 by screws 71 and bolts 72 at positions corresponding to the vertical spacing between the ceiling panel 4 and the beams 13 . By doing so, the ceiling panel 4 and the support beam 13 are joined at a predetermined height.

Here, a design example of the horizontal force transmission member 5 of this embodiment will be described.
First, for the horizontal inertial force at the time of an earthquake on the ceiling surface 4a that is borne by the horizontal force transmission member 5 at one location, a numerical value on the safe side is calculated using equation (1). In addition, the horizontal force transmission member 5 shall include the height adjustment member 7. As shown in FIG.
For example, the maximum design horizontal seismic coefficient (maxK) is 2.2, the ceiling maximum design load (maxW) is 30kg/m ² × 9.8N/kg, the maximum installation interval (ruling width) (maxb ) is 10 m (here, 10 m/2), and the maximum fulcrum distance (maxl) of the horizontal force transmission member is 2.5 m, the maximum tension (maxH) of the horizontal force transmission member is 8085 N from equation (1). becomes.

Next, the operation of the earthquake-resistant ceiling structure described above will be described in detail based on the drawings.
In this embodiment, as shown in FIG. 3, by joining the end portion 4c of the ceiling panel 4 to the support beam 13 near the height of the ceiling surface via the horizontal force transmission member 5, the ceiling panel with high in-plane rigidity Using the characteristics of 4, the horizontal inertial force of the ceiling that acts during an earthquake can be reliably transmitted to the building frame, or can be transmitted to the building frame through the support beams 13, and the ceiling can be integrated horizontally with the building frame. behave in the direction That is, it is possible to suppress the amplification of the vibration of the ceiling and prevent the ceiling from colliding with the walls, pillars, beams, and other structures of the building as in the past.

In addition, in the present embodiment, as described above, the ceiling portion behaves in the horizontal direction integrally with the support beams 13 installed near the height of the ceiling surface, which is less susceptible to inter-story displacement. This eliminates the need to provide a horizontal clearance between them, and can be applied to buildings such as clean rooms that require airtightness both in normal times and during earthquakes.
Furthermore, in the present embodiment, since no seismic member is arranged other than the horizontal force transmission member 5 provided at the end 4c of the ceiling panel 4, the degree of freedom in facility arrangement is ensured, and designability is reduced. I don't even have to.

In addition, in this embodiment, the height adjustment member 7 can be arranged to match the vertical gap between the ceiling panel 4 and the beams 13, so that the ceiling panel 4 and the beams 13 can be joined together. can be easily done.

As described above, in the earthquake-resistant ceiling structure 1 according to the present embodiment, airtightness can be ensured without installing diagonal members or tensile members, and without ceiling clearance.

Although the embodiments of the earthquake-resistant ceiling structure according to the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be appropriately modified without departing from the scope of the present invention.

For example, in the present embodiment, the horizontal force transmission member 5 fixed to the ceiling panel 4 and the support beam 13 are joined using the height adjustment member 7, but the height adjustment member 7 may be omitted. is also possible.

In this embodiment, the ceiling panel 4 is joined to the support beams 13 of H-shaped steel, which are the support structure, but the support structure is not limited to the support beams 13 . For example, the support structure may be a rectangular steel pipe support beam or a reinforced concrete support beam. Furthermore, the joint portion of the ceiling panel 4 is not limited to the beam material, and for example, the ceiling panel 4 may be joined to the pillar 12, which is the building skeleton, via a horizontal force transmission member.

Further, in this embodiment, the suspended ceiling using the ceiling joists 2 and the joists 3 is used, but the structure is not limited to this. For example, a structure of a suspended ceiling using a T-bar may be used without using the ceiling joists 2 and 3.

In addition, it is possible to appropriately replace the components in the above-described embodiments with well-known components without departing from the scope of the present invention.

1 earthquake-resistant ceiling structure 2 joist receiver 3 joist 4 ceiling panel 4a ceiling surface 4b upper surface 4c end 5 horizontal force transmission member 6 suspension member 7 height adjustment member 10 building skeleton 11 superstructure 12 pillar 13 support beam (support structure )
X1 First horizontal direction X2 Second horizontal direction

Claims (2)

a ceiling panel that is suspended and supported by the upper structure of the building frame via suspension members and that forms a suspended ceiling without installing any earthquake-resistant members made of diagonal members or tensile members;
a horizontal force transmission member coupled to an upper surface of an edge of the ceiling panel;
An end portion of the ceiling panel is joined to the building frame or a support structure portion of the building frame via the horizontal force transmission member ,
The horizontal force transmission member is designed based on the maximum tension calculated from the following formula (1),
maxH=maxK×maxW×maxb×maxl (1)
Note that maxH is the maximum tension (N) of the horizontal force transmission member
maxK: Maximum design horizontal seismic coefficient
maxW: maximum design load of the ceiling (N/m ² )
maxb: Maximum installation interval of horizontal force transmission members (m)
maxl: Maximum distance between fulcrums of horizontal force transmission member (m)
An earthquake-resistant ceiling structure characterized by: The support structure is a support beam installed between columns of the building skeleton,
A height adjustment member is provided between the horizontal force transmission member and the support beam, and is capable of adjusting and fixing a vertical gap between the horizontal force transmission member and the support beam. The earthquake-resistant ceiling structure according to claim 1.

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