CN101238258B

CN101238258B - Floor-ceiling structure

Info

Publication number: CN101238258B
Application number: CN2006800291458A
Authority: CN
Inventors: 村桥喜满; 川上宽明; 增田京子; 次桥一树
Original assignee: Kobe Steel Ltd; Nippon Steel Corp
Current assignee: Kobe Steel Ltd; Nippon Steel Corp
Priority date: 2005-08-12
Filing date: 2006-08-08
Publication date: 2010-12-01
Anticipated expiration: 2026-08-08
Also published as: TWI322214B; KR20080037706A; CN101238258A; WO2007020841A1; TW200716833A

Abstract

A floor-ceiling structure between an upper story floor board and a lower story ceiling board, comprising a plurality of floor joists disposed in a specific direction in the state of being arranged roughly parallel with each other, side joists disposed at positions for holding the floor joists in the specific direction in the state of being arranged parallel with these floor joists, end joists which are disposed at positions for holding the floor joists in a direction crossing perpendicularly to the specific direction and to which the end parts of the side joists and the floor joists are fixed, and a ceiling beam for suspending the ceiling board disposed across the end joists so as to be roughly parallel with the side joists. At least one joist among a joist group formed of the side joists and the plurality of floor joists is supported by the wall of the upper story or the lower story, and the ceiling beam is installed only near the wall.

Description

Floor-ceiling structure

Technical Field

The present invention relates to a floor-ceiling structure (floor-ceiling structure) supported by a plurality of walls, and more particularly, to a floor-ceiling structure having excellent soundproof performance.

Background

In recent years, in residential buildings, a floor structure (steel house) in which a floor is joined to a frame made of a frame material and a beam material made of metal profiles has been used instead of a floor structure in which a floor is joined to a frame made of wood. The steel house uses a framework formed by a frame material and a beam material made of metal section bars, so that the vibration resistance and the durability can be improved.

In addition, when such a floor structure having a framework formed of a frame member and a beam member made of metal profiles is used as a boundary floor (hereinafter, referred to as a floor-ceiling structure) of a boundary between upper and lower floors of a residential building (hereinafter, referred to as a floor-ceiling structure), although the floor structure is improved over a floor structure having a conventional wood framework, sound-proof measures are required because of the increase in consumer demand. In particular, measures against impact sound (hereinafter referred to as heavy floor impact sound) generated downstairs when a person jumps or walks are required.

As a method for reducing impact noise of a general weight floor, there are (1) a method of increasing the weight of a floor structure and (2) a method of increasing the bending rigidity of a floor structure. Further, as a method of quickly attenuating floor vibration after an impact force acts and suppressing a sense of discomfort, (3) a method of imparting vibration damping property to a floor, and the like are known. Further, the methods (1), (2) and (3) may be used together.

Patent document 1 discloses a ceiling structure and a building in which the number of components is not increased, and the vibration in the upstairs weight floor impact sound vibration mode is dispersed by a ceiling to reduce the impact sound to the downstairs weight floor without affecting the piping in the space inside the floor.

In the ceiling structure and the building described in patent document 1, the vibration in the vibration mode of the upstairs weight floor impact sound is dispersed by the ceiling panel by the weight member attached to the ceiling rib of the ceiling panel, and the impact sound to the downstairs weight floor is reduced. Further, since the peripheral edge portion of the ceiling panel to which the weight member is attached to the floor joist via the vibration-proof rubber, the vibration of the ceiling panel is more effectively dispersed, and the effect of reducing the weight of the floor impact sound by the weight member can be further improved.

Further, patent document 2 discloses a soundproof ceiling structure that can reduce floor impact noise by suppressing transmission of vibration from upstairs to downstairs at both the time of light weight impact and the time of heavy weight impact, and that can improve sound insulation particularly in a low frequency region.

In the soundproof ceiling structure described in patent document 2, when vibration is transmitted from the ceiling base material to the ceiling member via the suspending members, the vibration level of the ceiling member due to solid propagation can be significantly reduced by the vibration damping action of the vibration damping member.

Further, patent document 3 discloses a ceiling suspension capable of absorbing vibration in a large frequency band.

The ceiling suspension described in patent document 3 includes an upper attachment member attached to a beam on the back surface of a ceiling, and a lower attachment member extending downward from the upper attachment member and supporting a ceiling substrate through a lower end portion, and a damper member is provided at a connection portion between the upper attachment member and the lower attachment member, and the damper member includes a plurality of vibration-proof rubbers having different vibration absorption frequency bands, so that an effect of absorbing vibrations in a relatively large frequency band can be obtained.

However, in any of the structures of patent documents 1 to 3, it is necessary to add a weight member, to seal a fluid in the interior of the elastic body, or to arrange vibration-proof rubbers having different hardness in a superimposed manner. Therefore, even if there are few components or the cost increases at one place, the number of components and the cost increase sharply as the structure becomes larger.

[ patent document 1 ] Japanese patent application laid-open No. 2002-121856

[ patent document 2 ] Japanese patent application laid-open No. Hei 10-183849

[ patent document 3 ] Japanese patent application laid-open No. 2003-313987

Disclosure of Invention

The object of the present invention is to provide a floor-ceiling structure capable of greatly reducing floor impact sound in a large frequency band without requiring an increase in parts and a complicated design.

In order to achieve the above object, the present invention is a floor-ceiling structure interposed between an upper floor and a lower ceiling, comprising: a plurality of floor joists (floor joists) arranged in a specific direction in a state of being arranged substantially parallel to each other; side joists (side joists) arranged substantially parallel to the floor joists and positioned to hold the floor joists therebetween in the specific direction; an end joist (head joist) disposed at a position sandwiching the floor joist from a direction orthogonal to the specific direction, and fixing the side joist and an end portion of the floor joist, the end joist and the side joist constituting a frame; and ceiling beams (ceiling beams) for suspending the ceiling, the ceiling beams spanning the end joists and being arranged substantially parallel to the side joists; wherein at least one joist in a joist group consisting of the side joists and the plurality of floor joists is supported by a wall of the upper or lower floor, and the ceiling joists are provided only in the vicinity of the wall.

Drawings

Fig. 1 is a perspective view showing an example of the floor-ceiling structure according to embodiment 1.

Fig. 2 is a top view of the floor-ceiling structure of fig. 1.

Fig. 3 is a schematic perspective view showing details of the ceiling beam.

Fig. 4(a) is a sectional view showing a structure of a floor-ceiling structure, and fig. 4(b) is a view for explaining an operation in a case where a force is applied to a floor.

Fig. 5(a) is a schematic cross-sectional view of the floor panel, and fig. 5(b) to 5(e) are schematic views showing first to fourth order modes of the floor panel, respectively.

Fig. 6(a) is a schematic cross-sectional view of the floor panel, and fig. 6(b) to 6(e) are schematic views showing first to fourth order modes of the floor panel, respectively.

Fig. 7(a1), 7(a2), 7(b1), and 7(b2) are schematic views showing examples of the arrangement of the walls.

Fig. 8(a1), 8(a2), 8(b1), and 8(b2) are schematic views showing examples of the arrangement of the walls.

Fig. 9(a) to 9(d) are plan views showing another example of the floor-ceiling structure.

FIG. 10 is a graph showing the vibration transmittances of examples 1 to 3 and comparative example 1.

Fig. 11 is a graph showing the results of the measurement of the weight floor impact sound.

Fig. 12 is a graph showing the results of the impact sound test of the light weight floor.

FIGS. 13(a) to 13(c) are views showing examples 1 to 3, respectively, and FIG. 13(d) is a view showing comparative example 1.

(symbol description)

11 end joist

30 beam for ceiling

31 suspension member

32 suspended ceiling rib bearing beam

33 ceiling rib

50 floor

Detailed Description

Embodiments of the present invention will be described below.

(embodiment 1)

Fig. 1 is a perspective view showing an example of a floor-ceiling structure 100 according to embodiment 1, and fig. 2 is a plan view of the floor-ceiling structure 100 of fig. 1.

The floor-ceiling structure 100 of fig. 1 and 2 is a structure between the floor 50 of the upper layer and the ceiling 60 of the lower layer (not shown), and mainly includes end joists 11, side joists 12, floor joists 20, ceiling beams 30, suspension members 31 (not shown), ceiling bearers 32 (not shown), and ceiling ribs 33 (not shown). The ceiling beams 30, the suspension members 31, the ceiling rib bearers 32, and the ceiling ribs 33 constitute ceiling support portions for suspending the ceiling 60 from the end joists 11.

As shown in fig. 1 and 2, in the floor-ceiling structure 100, a rectangular frame is formed by connecting end portions of a pair of end joists 11 arranged substantially parallel to each other and a pair of side joists 12 arranged substantially perpendicular to the end joists 11. In the frame, a plurality of floor joists 20 are arranged substantially parallel to the side joists 12, and both ends of the floor joists 20 are fixed to the pair of end joists 11. In other words, the pair of side joists 12 are disposed at positions sandwiching the floor joists 20 from the direction in which the floor joists 20 are arranged, and the pair of end joists 11 are disposed at positions sandwiching the floor joists 20 from the direction orthogonal to the direction in which the floor joists 20 are arranged. The floor 50 is fixedly supported by a pair of end joists 11 and side joists 12, and a plurality of floor joists 20.

As shown in fig. 2, a plurality of ceiling joists 30 are disposed in the frame substantially parallel to the pair of side joists 12 and the plurality of floor joists 20, and both end portions of the ceiling joists 30 are fixed to the pair of end joists 11. The number and arrangement of the ceiling beams 30 will be described in detail later.

Fig. 3 is a schematic perspective view showing details of the ceiling beam 30. As shown in fig. 3, the upper surfaces of the pair of end joists 11, the pair of side joists 12, and the plurality of floor joists 20 are substantially at the same height and can support the floor 50. The end joist 11 has a cross-sectional shape of approximately コ with an opening on the inside, and both ends of the side joists 12 and the floor joists 20 enter the opening of the end joist 11. The cross-sectional shape of the end joist 11 is not limited to the approximately コ -shaped cross-section, and may be other shapes such as an I-shaped cross-section. The ceiling beam 30 has a substantially コ -shaped cross section. The cross-sectional shape of the ceiling beam 30 is not limited to the approximately コ -shaped cross-section, and may be any shape such as square-shaped or zigzag-shaped cross-section.

As shown in fig. 4(a), a suspension member 31 is suspended from the ceiling beam 30, and the suspension member 31 extends downward from the ceiling beam 30. The suspension member 31 is made of wood or metal, and particularly, in the case of metal, it is also called a suspension metal object or a suspension metal member. A ceiling rib 33 for fixing the ceiling 60 is attached to a lower portion of the suspension member 31 via a ceiling rib support 32. The suspended ceiling rib bearer 32 is a rod-shaped member extending in a direction substantially orthogonal to the suspended ceiling rib 33. The ceiling rib support 32 may be attached to the lower end of the suspension member 31 in a state of protruding downward from the suspension member 31, or may be attached to the upper side of the lower end of the suspension member 31.

The ceiling beams 30 are provided so as not to protrude from the upper surfaces of the pair of end joists 11. The suspension member 31 is also provided so as not to protrude from the upper surfaces of the pair of end joists 11, but to protrude from the lower surfaces thereof. That is, the ceiling beam 30 is provided so as not to contact the floor 50, and the ceiling 60 is attached to the ceiling beam 30 via the suspension members 31, the ceiling rib receiving members 32, and the ceiling ribs 33.

Next, the principle of transmission of vibration of the floor-ceiling structure 100 will be explained. Fig. 4(a) and 4(b) are diagrams for explaining the transmission of vibration from the floor 50. Fig. 4(a) is a sectional view showing the structure of the floor-ceiling structure 100, and fig. 4(b) is a view for explaining an operation in the case where a force F is applied to the floor 50.

First, as shown in fig. 4(b), a force F is applied to the floor 50. The vibration thus generated is transmitted to the end joists 11, the side joists 12 and the floor joists 20 as a solid propagation component. The vibration transmitted to the end joists 11 is transmitted to the ceiling beams 30, and the vibration transmitted to the side joists 12 and the plurality of floor joists 20 is transmitted to the ceiling beams 30 via the end joists 11. The vibration transmitted to the ceiling beam 30 is transmitted to the ceiling 60 via the suspension members 31, the ceiling rib beams 32, and the ceiling ribs 33.

Further, in the case where the force F is applied to the floor panel 50, at the same time, the vibration of the floor panel 50 is transmitted as an airborne component (sound) to the ceiling panel 60 via the air inside the floor-ceiling structure body. In such a structure, the solid propagating component is dominant compared to the air propagating component.

Next, a general mode of vibration in the structure of the floor panel 50, the frame body, and the floor joists 20 of the present embodiment (hereinafter, the floor panel 50, the floor joists 20, and the frame body (the end joists 11 and the side joists 12) are collectively referred to as a floor panel 200) will be described. In the present embodiment, since the occurrence of the vibration mode in the longitudinal direction of the end joist 11 of the floor panel 200 is relatively significant, the vibration mode in only one direction will be described.

Fig. 5(a) to 5(e) are schematic views for explaining the vibration of the floor panel in which the two

floor panels

200a and 200b are arranged in the longitudinal direction of the end joist 11. Fig. 5(a) is a schematic cross-sectional view of the floor panel, fig. 5(b) shows a first-order pattern of the floor panel, fig. 5(c) shows a second-order pattern of the floor panel, fig. 5(d) shows a third-order pattern of the floor panel, and fig. 5(e) shows a fourth-order pattern of the floor panel. The space partitioned by the

floor boards

200a and 200b has an upper layer at the upper part and a lower layer at the lower part.

As shown in fig. 5(a), the two

floor boards

200a and 200b are disposed in a state where the side joists 12 are in contact with each other. The

floor boards

200a and 200b may be arranged so that a predetermined gap is formed between the side joists 12, or may be integrally configured so that the side joists 12 are used in common.

A wall 70 is provided vertically at an end portion of one end side (left side in fig. 5 a) of the floor panel 200a, and the wall 70 is provided on an upper surface of a central portion of the floor panel 200 a. Specifically, the vertically disposed wall 70 is connected to the side joist 12 at one end side of the floor 200a, and the 2 nd wall 70 from the left of the upper floor is connected to the floor joist 20 at the center. In other words, the side joists 12 at one end are supported by the walls 70 of the lower and upper floors, and the floor joists 20 at the center are supported by the walls 70 of the upper floor.

Further, a wall 70 is provided vertically at the end portion on the other end side (right side in fig. 5 (a)) of the floor panel 200b, and a wall 70 is provided on the lower surface of the center portion of the floor panel 200 b. Specifically, the vertically disposed wall 70 is connected to the side joist 12 on the other end side of the floor 200a, and the 2 nd wall 70 from the right of the lower floor is connected to the floor joist 20 in the center portion. In other words, the side joists 12 on the other end side are supported by the walls 70 of the lower and upper floors, and the floor joists 20 in the center portion are supported by the walls 70 of the lower floor.

Hereinafter, for the sake of explanation, the distance from wall 70 provided only at the upper layer of floor 200a to wall 70 provided only at the lower layer of floor 200b will be referred to as distance L.

When focusing on the floor 200a and the floor 200b shown in fig. 5(a), the positions of the frame corresponding to the joists supported by the wall 70 become nodes of vibration. Therefore, when the force F applied to the floor panel 50 contains a frequency component matching the first-order natural frequency, the floor panel 200a and the floor panel 200b vibrate in the first-order mode as shown in fig. 5 (b). That is, the amplitude of the portion at a distance L/2 from the wall 70 existing only in the upper layer is the maximum (antinode), and the amplitude of the portion near the wall 70 is the minimum (node).

When the force F applied to the floor panel 50 contains a frequency component matching the second order natural frequency, the floor panel 200a and the floor panel 200b vibrate in the second order mode as shown in fig. 5 (c). In this case, the amplitude is maximum at the portions at distances L/4 and 3L/4 from the wall 70 existing only in the upper layer, and the amplitude is minimum at the portion L/2 and the portion near the wall 70.

Further, when the force F applied to the floor panel 50 contains a frequency component matching the third-order natural frequency, the floor panel 200a and the floor panel 200b vibrate in the third-order mode as shown in fig. 5 (d). In this case, the amplitude is minimum at the portions at distances of L/3, 2L/3 from the wall 70 existing only in the upper layer, and the portions near the wall 70.

Further, when the force F applied to the floor panel 50 contains a frequency component matching the fourth-order natural frequency, the floor panel 200a and the floor panel 200b vibrate in the fourth-order mode as shown in fig. 5 (e). In this case, the amplitude is minimum at the portions at distances of L/4, L/2, 3L/4 from the wall 70 existing only in the upper layer, and the portions near the wall 70.

Therefore, considering the longitudinal vibration mode of the end joists 11 of the

floor boards

200a and 200b, it is preferable to provide the ceiling beams 30 at the portions of the

floor boards

200a and 200b where the vibration is small.

Next, another example of the general vibration mode described in fig. 5 will be described. Fig. 6(a) to 6(e) are schematic diagrams for explaining the vibration of the floor panel configured by arranging two

floor panels

200a and 200b in the longitudinal direction of the end joist 11.

Fig. 6(a) is a schematic cross-sectional view of the floor, fig. 6(b) shows a first-order pattern in the longitudinal direction of the end joist 11 of the floor, fig. 6(c) shows a second-order pattern in the longitudinal direction of the end joist 11 of the floor, fig. 6(d) shows a third-order pattern in the longitudinal direction of the end joist 11 of the floor, and fig. 6(e) shows a fourth-order pattern in the longitudinal direction of the end joist 11 of the floor.

As shown in fig. 6, walls 70 are provided above and below one end of the floor panel 200a and the other end of the floor panel 200 b. Further, a wall 70 is provided on the upper side of the floor 200 b. That is, similarly to the description with reference to fig. 5(a), the side joists 12 on one end side of the floor 200a and the side joists 12 on the other end side of the floor 200b are supported by the lower and upper walls 70, and the floor joists 20 near one end side of the floor 200b are supported by the upper wall 70.

In addition, a distance from the wall 70 on the left side in the drawing to the wall 70 on the upper side is set to L11 below, and a distance from the wall 70 in the center in the drawing to the wall 70 on the right side in the drawing is set to L12.

A portion of the

floor boards

200a and 200b within the range of the distance L11 generates vibrations of the first order mode, the second order mode, the third order mode, and the fourth order mode on the

floor boards

200a and 200b, respectively, in response to the applied force. However, in any one of the first order mode to the fourth order mode, the amplitude of the floor 200a is small in the range of 1/8 or less at a distance L11 from the wall 70. That is, the ceiling beam 30 is provided only on the left side of the wall 70 provided only on the upper layer and only on the portion close to the wall 70, thereby minimizing the vibration transmissivity.

Further, also, a portion of the floor panel 200b within the range of the distance L12 generates vibrations in the first order mode, the second order mode, the third order mode, and the fourth order mode, respectively, in response to the applied force. However, in any one of the first order mode to the fourth order mode, the amplitude of the floor 200b is small in the range of 1/8 or less at a distance L12 from the wall 70. That is, the ceiling beam 30 is provided only on the right side of the wall 70 provided only on the upper layer and only on the portion close to the wall 70, thereby minimizing the vibration transmissivity.

As described above, the ceiling beam 30 is provided only on the left side of the wall 70 provided on the upper layer in the range of 1/8 or less from the wall 70 of L11 and only on the right side of the wall 70 provided on the upper layer in the range of 1/8 or less from the wall 70 of L12, whereby it is possible to reduce the transmission of the vibration generated in the

floors

200a and 200b to the ceiling 60 via the solid propagation component.

In particular, when the ceiling beam 30 is disposed in the range of distances L11 and L12 of 1/4 or less from the wall 70, the antinodes of the first order mode and the second order mode are not included, and therefore, the vibration of the ceiling caused by the first order mode and the second order mode can be reduced, when the ceiling beam 30 is disposed in the range of distances L11 and L12 of 1/6 or less from the wall 70, the antinodes of the first order mode, the second order mode, and the third order mode are not included, and therefore, the vibration of the ceiling caused by the first order mode, the second order mode, and the third order mode can be reduced, and when the ceiling beam 30 is disposed in the range of distances L11 and L12 of 1/8 or less from the wall 70, the antinodes of the first order to fourth order modes are not included, and therefore, the vibration of the ceiling caused by the first order to fourth order mode can be reduced.

Next, a specific example of the arrangement of the wall 70 will be described. Fig. 7(a1) to 7(b2) and 8(a1) to 8(b2) are schematic views showing examples of the arrangement of the wall 70.

Fig. 7(a1) and 7(a2) show the wall 70 provided below the floor panel 200a, fig. 7(b1) and 7(b2) show the wall 70 provided above the contact portion between the floor panel 200a and the floor panel 200b, fig. 8(a1) and 8(a2) show the wall 70 provided above and below the contact portion between the floor panel 200a and the floor panel 200b, and fig. 8(b1) and 8(b2) show the wall 70 provided below the contact portion between the floor panel 200a and the floor panel 200 b.

When the wall 70 is provided below the floor 200a as shown in fig. 7(a1), the ceiling beam 30 is preferably disposed near the wall 70 as shown in fig. 7(a 2). That is, by providing the ceiling beams 30 near the nodes of the vibration of the floor 200a, the vibration transmitted to the ceiling 60 can be minimized.

In particular, if considering vibrations from the first-order mode to the fourth-order mode, the position of the ceiling beam 30 is preferably in the range of 1/4 or less at a distance L1a (L1a ') from the wall 70, more preferably in the range of 1/6 or less at a distance L1a (L1a ') from the wall 70, and further preferably in the range of 1/8 or less at a distance L1a (L1a ') from the wall 70, and the closer to 0 the distance from the wall 70 is the more preferable.

As a result, since the ceiling beam 30 is disposed at the portion of the floor 200 where the amplitude is minimum, the transmission of the vibration of the floor to the ceiling 60 can be suppressed.

Similarly, when the wall 70 is provided above the floor 200a as shown in fig. 7(b1) and 8(a1), particularly when vibration from the first-order mode to the fourth-order mode is considered as shown in fig. 7(b2) and 8(a2), the position of the ceiling beam 30 is preferably at a distance L1b (L1b ') or 1/4 (L2a ') (L2a ') from the wall 70, and the distance from the wall 70 is preferably as close to 0.

As a result, since the ceiling beam 30 is disposed at the portion of the floor 200 where the amplitude is minimum, the transmission of the vibration of the floor 200 to the ceiling 60 can be suppressed.

In addition, as shown in fig. 8(b1), when the wall 70 is provided below the

floor boards

200a and 200b, as shown in fig. 8(b2), particularly when vibration from the first-order mode to the fourth-order mode is considered, the ceiling beam 30 is preferably disposed at a position 1/4 of L2b (L2 b') from the wall 70, and the closer to 0 the distance from the wall 70 is, the more preferable.

Next, another example of the floor-ceiling structure 100 shown in fig. 2 will be described. Fig. 9(a) to 9(d) are plan views showing another example of the floor-ceiling structure 100.

Fig. 9(a) shows a floor-ceiling structure 100a, in which one end joist 11 is divided into two end joists 11a, 11b, the end joists 11a, 11b are coupled via auxiliary side joists 12a, and one side joist 12 is coupled to the end joist 11b via auxiliary side joists 12b, and a plurality of rolling prevention portions 35 are provided at appropriate locations, fig. 9(b) shows a floor-ceiling structure 100b, one end joist 11 is divided into two end joists 11a, 11b, the end joists 11a, 11b are coupled via auxiliary side joists 12a, fig. 9(c) shows a floor-ceiling structure 100c, one end joist 11 is divided into 3 end joists 11d to 11f, an end joist 11e is coupled to the end joists 11d, 11f via auxiliary side joists 12c, 12d, and a plurality of rolling prevention portions 35 are provided at appropriate locations, fig. 9(d) shows a floor-ceiling structure 100d, in which one end joist 11 is divided into 3 end joists 11d to 11f, and an end joist 11e is connected to the end joists 11d and 11f via auxiliary side joists 12c and 12 d. In these floor-ceiling structures 100a to 100d, the auxiliary side joists 12b may not be provided and the side joists 12 may be extended, or the auxiliary side joists 12a, 12c and 12d may not be provided and the floor joists 20 may be extended.

As shown in fig. 9(a) to 9(d), the floor-ceiling structures 100a to 100d are not limited to rectangular shapes as shown in fig. 2, and may have any other shapes. In these cases, the vibration transmitted from the floor to the ceiling can be reduced by providing the ceiling beam 30 only in the vicinity of the wall 70. In the present embodiment, the plurality of rolling prevention portions 35 have the same function as the end joists 11.

When at least 5 floor joists 20 are disposed between the walls 70, it is preferable that the ceiling beams 30 are disposed in the range from each wall 70 to the 2 nd floor joists 20. In this case, since the ceiling beam 30 is provided at a position close to the wall 70, a large amplitude of the floor 50 is not transmitted to the ceiling 60, and vibration can be reduced.

In the present embodiment, the case where the wall exists over the entire length of the side joists 12 and the floor joists 20 has been described, but the present invention is not limited thereto, and similar effects can be obtained even for a window or a door of a building in which a structure exists in a part of the wall. The support is not limited to the wall, and may be supported by any other optional additional member, such as a column.

As described above, in the floor-ceiling structure according to the present invention, when a force acts on the floor 200 and vibration occurs, the vibration is transmitted to the frame having the end joists 11 and the side joists 12. Since one or more joists in a joist group consisting of the pair of side joists 12 and the plurality of floor joists 20 are supported by the wall 70, the vibration of the frame at a position corresponding to the joists supported by the wall 70 is reduced, and the vibration of a portion away from this position is increased. Therefore, since the ceiling beam 30 is provided only in the vicinity of the wall 70, the vibration of the ceiling beam 30 can be reduced, and the vibration transmitted from the floor 50 to the ceiling 60 can be reduced.

As a result, the impact sound in a large frequency band can be reduced with a simple configuration. In particular, since the contribution of the solid propagation component of the heavy floor impact sound is large, the heavy floor impact sound can be reduced by reducing the vibration of the ceiling beam 30.

< example A >

(examples 1 to 3)

As examples 1 to 3, the vibration transfer rate from the floor to the ceiling was simulated for the case where the ceiling beam 30 was disposed within the range of L/4 of the distance from the wall 70 (see fig. 13(a)), the case where the ceiling beam 30 was disposed within the range of L/6 of the distance from the wall 70 (see fig. 13(b)), and the case where the ceiling beam 30 was disposed within the range of L/8 of the distance from the wall 70 (see fig. 13 (c)).

Further, as a simulation condition, the vibration of the ceiling when the vibration was applied to 1 point on the upper surface of the floor was calculated by the finite element method. The point of applied vibration was selected to produce the largest weight floor impact sound when the weight floor impact sound was tested in the conventional structure based on JIS a 1418. The ceiling vibration uses the sum of the vibration velocities of a plurality of points arranged substantially uniformly as a representative value.

Comparative example 1

As comparative example 1, the vibration transmission rate from the floor to the ceiling of the conventional structure (see fig. 13(d)) in which the ceiling beam 30 was provided on the entire surface of the floor-ceiling structure was simulated.

FIG. 10 is a graph showing the vibration transfer rate from the floor to the ceiling in examples 1 to 3 and comparative example 1.

The vertical axis of fig. 10 represents the vibration transmissivity (dB) and the horizontal axis represents the frequency (Hz). Here, the vibration transmission rate (dB) is a value obtained by dividing the representative value of the vibration velocity of the ceiling by the vibration velocity of the vibration point applied to the floor logarithmically.

< evaluation >

As shown in fig. 10, in a frequency band (50Hz band (44.7Hz to 56.2Hz)) generally determining the L level of the floor impact sound, it was confirmed that the vibration transmission rate decreased in the order of comparative example 1, example 2, and example 3. This confirmed that the reduction in the ceiling vibration was large in the order of distances from the wall 70 of L/4, L/6, and L/8.

< example B >

Next, the weight floor impact sound and the light floor impact sound were measured according to JIS a1418 in the same manner as in example 3 and comparative example 1.

Fig. 11 and 12 are diagrams showing the results of measuring the impact sound of the heavy floor and the impact sound of the light floor.

The vertical axis of fig. 11 represents the weight floor impact sound level (5dB/grid), the vertical axis of fig. 12 represents the light floor impact sound level (5dB/grid), and the horizontal axes of fig. 11 and 12 represent the 1/1-fold frequency band center frequency (Hz).

As shown in fig. 11, in example 3, a decrease of about 5dB in the weight floor impact sound level in the range of the frequency of 63Hz band or more and 1kHz band or less was observed as compared with comparative example 1. Further, a 10dB reduction can be achieved in the 2kHz band and the 4kHz band.

On the other hand, as shown in fig. 12, in example 3, the impact sound level of the light floor can be reduced by 3dB in the frequency bands of 63Hz and 125Hz as compared with comparative example 1. In addition, a 2dB reduction was observed in the range of the 250Hz band and 4kHz band.

In the floor-ceiling structure of the present invention, the floor 50 corresponds to a floor, the floor joists 20 correspond to floor joists, the side joists 12 correspond to side joists, the end joists 11 correspond to end joists, the ceiling joists 30 correspond to ceiling joists, the ceiling 60 corresponds to a ceiling, the floor-ceiling structure 100 corresponds to a floor-ceiling structure, the walls 70 correspond to walls, the suspension members 31 correspond to suspension members, the ceiling ribs 33 correspond to ceiling ribs, and the ceiling rib bearers 32 correspond to ceiling rib bearers.

Further, although the ceiling beams 30 are provided only in the vicinity of the wall 70 in the above embodiment, for example, it is possible to reduce the vibration transmitted from the floor 50 to the ceiling 60 by not providing at least one of the ceiling beams 30, the suspension members 31, the ceiling rib support beams 32, and the ceiling ribs 33 constituting the ceiling support portion in a region other than the vicinity of the wall 70.

For example, even if the ceiling beam 30 is provided in a region other than the vicinity of the wall 70, the suspension member 31 may not be provided in the region other than the vicinity of the wall 70. Alternatively, even if the ceiling beams 30 and the suspension members 31 are provided in the regions other than the vicinity of the wall 70, the ceiling rib supports 32 and the ceiling ribs 33 may not be provided in the regions other than the vicinity of the wall 70.

Further, if at least 1 of the ceiling beams 30, the suspension members 31, the ceiling rib supports 32, and the ceiling ribs 33 is not connected to other members in the region other than the vicinity of the wall 70, and the one member can be independently displaced in a state of being separated from the other members, the vibration transmitted from the floor 50 to the ceiling 60 can be reduced. That is, all of the ceiling beams 30, the suspension members 31, the ceiling rib supports 32, and the ceiling ribs 33 may be connected only in the region near the wall 70.

In the above-described embodiment and modifications, the ceiling rib support 32 may be omitted, and the ceiling rib 33 may be directly attached to the suspension member 31.

As described above, the floor-ceiling structure according to claim 1 is a floor-ceiling structure between an upper floor and a lower ceiling, and includes: a plurality of floor joists arranged in a specific direction in a state of being arranged substantially parallel to each other; side joists arranged in a position that sandwiches the floor joists from the specific direction in a state of being arranged substantially parallel to the floor joists; an end joist disposed at a position sandwiching the floor joist from a direction orthogonal to the specific direction and fixing end portions of the side joist and the floor joist; and a ceiling beam for suspending the ceiling, the ceiling beam spanning the end joist and being arranged substantially parallel to the side joist; wherein at least one joist in a joist group consisting of the side joists and the plurality of floor joists is supported by a wall of the upper or lower floor, and the ceiling joists are provided only in the vicinity of the wall.

In the floor-ceiling structure according to claim 1, the floor joists are provided on the end joists substantially in parallel to the side joists in the frame body including the side joists and the end joists. In the frame body composed of the side joists and the end joists, the ceiling beams are provided on the end joists substantially in parallel to the side joists. At least 1 joist in a joist group consisting of a side joist and a plurality of floor joists is supported by a wall, and the ceiling joist is only arranged near the wall.

Here, when a force acts on the floor to generate vibration, the vibration is transmitted to the frame body composed of the side joists and the end joists. Since at least 1 joist in the joist group is supported by the wall, the vibration of the frame at the position corresponding to the joist supported by the wall is reduced, and the vibration of the part away from the position is increased. Therefore, since the ceiling beam is provided only in the vicinity of the wall, the vibration of the ceiling beam can be reduced, and the vibration transmitted from the floor to the ceiling can be reduced.

As a result, the impact sound in a large frequency band can be reduced with a simple configuration. In particular, in such a structure, the contribution of the solid propagation component is greater than that of the air propagation component, and therefore, a large reduction effect can be obtained by reducing the vibration of the ceiling beam.

Preferably, the joist assembly comprising the side joists and the plurality of floor joists includes joists supported by a1 st wall of the upper or lower deck and joists supported by a2 nd wall of the upper or lower deck, the 2 nd wall is disposed at a position spaced apart from the 1 st wall, the ceiling joists are disposed in the vicinity of the wall in a region between the 1 st wall and the 2 nd wall, and the distance from each wall to the ceiling joists in the vicinity of each wall is 1/4 or less of the distance between the 1 st wall and the 2 nd wall.

In this case, since the distance from each wall to the ceiling beam near each wall is not more than 1/4 of the distance between the 1 st wall and the 2 nd wall, even when the floor vibrates in the first order mode or the second order mode in the longitudinal direction of the end joist, for example, the ceiling beam is provided near the node of the vibration (the portion with the smallest amplitude) without being disposed on the antinode of the vibration (the portion with the largest amplitude), and therefore, the vibration transmitted from the floor to the ceiling can be reduced.

Preferably, the joist assembly comprising the side joists and the plurality of floor joists includes joists supported by a1 st wall of the upper or lower deck and joists supported by a2 nd wall of the upper or lower deck, the 2 nd wall is disposed at a position spaced apart from the 1 st wall, the ceiling joists are provided in the vicinity of the respective walls in a region between the 1 st wall and the 2 nd wall, and the distance from the respective walls to the ceiling joists in the vicinity of the respective walls is 1/6 or less of the distance between the 1 st wall and the 2 nd wall.

In this case, since the distance from each wall to the ceiling beam near each wall is not more than 1/6 of the distance between the 1 st wall and the 2 nd wall, even when the floor vibrates in the first order, second order, or third order modes in the longitudinal direction of the end joist, for example, the ceiling beam is provided near the node (the portion where the amplitude is the smallest) of the vibration without being disposed on the antinode (the portion where the amplitude is the largest) of the vibration, and therefore, the vibration transmitted from the floor to the ceiling can be reduced.

Preferably, the joist assembly comprising the side joists and the plurality of floor joists includes joists supported by a1 st wall of the upper or lower deck and joists supported by a2 nd wall of the upper or lower deck, the 2 nd wall is disposed at a position spaced apart from the 1 st wall, the ceiling joists are provided in the vicinity of the respective walls in a region between the 1 st wall and the 2 nd wall, and the distance from the respective walls to the ceiling joists in the vicinity of the respective walls is 1/8 or less of the distance between the 1 st wall and the 2 nd wall.

In this case, since the distance from each wall to the ceiling beam near each wall is not more than 1/8 of the distance between the 1 st wall and the 2 nd wall, even when the floor vibrates in the first to fourth order modes in the longitudinal direction of the end joist, for example, the ceiling beam is provided near the node (the portion with the smallest amplitude) of the vibration without being disposed on the antinode (the portion with the largest amplitude) of the vibration, and therefore, the vibration transmitted from the floor to the ceiling can be reduced.

Preferably, at least 5 floor joists are arranged between the 1 st wall and the 2 nd wall, and the ceiling beam is provided in a range from each of the walls to the 2 nd floor joists.

In this case, since the ceiling beam is provided at a position close to the wall, a large amplitude of the floor is not transmitted to the ceiling, and vibration can be reduced.

The floor-ceiling structure according to claim 2 is a floor-ceiling structure between a floor on an upper layer and a ceiling on a lower layer, and includes: a plurality of floor joists arranged in a specific direction in a state of being arranged substantially parallel to each other; side joists arranged in a position that sandwiches the floor joists from the specific direction in a state of being arranged substantially parallel to the floor joists; an end joist disposed at a position sandwiching the floor joist from a direction orthogonal to the specific direction and fixing end portions of the side joist and the floor joist; and a ceiling support portion for suspending the ceiling from the end joists; wherein at least one joist in a joist group consisting of the side joists and the plurality of floor joists is supported by the wall of the upper or lower floor, and the ceiling support section includes: a ceiling beam disposed across the end joists; a suspension member vertically provided on the ceiling beam; a ceiling rib bolster mounted on the suspension member; and a suspended ceiling rib mounted on the suspended ceiling rib bearer and fixing the ceiling; wherein at least one of the ceiling beam, the suspension member, the ceiling rib beam, and the ceiling rib is not provided in a region other than the vicinity of the wall.

In the floor-ceiling structure according to claim 2, the floor joists are provided on the end joists substantially in parallel to the side joists in the frame body including the side joists and the end joists. In addition, in the frame body composed of the side joists and the end joists, the ceiling supporting part is arranged on the end joists. At least 1 joist in a joist group consisting of a side joist and a plurality of floor joists is supported by a wall, and the ceiling support portion comprises a ceiling beam, a suspension member, a ceiling rib beam, and a ceiling rib, and at least one of the ceiling beam, the suspension member, the ceiling rib beam, and the ceiling rib is not provided in a region other than the vicinity of the wall.

Here, when a force acts on the floor to generate vibration, the vibration is transmitted to the frame body composed of the side joists and the end joists. Since at least 1 joist in the joist group is supported by the wall, the vibration of the frame at the position corresponding to the joist supported by the wall is reduced, and the vibration of the part away from the position is increased. Therefore, by not providing at least one of the ceiling beams, the suspension members, the ceiling rib support beams, and the ceiling ribs constituting the ceiling support portion in a region other than the vicinity of the wall, it is possible to reduce the vibration transmitted from the floor to the ceiling. Therefore, the impact sound in a large frequency band can be reduced with a simple configuration. In particular, in such a structure, since the contribution of the solid propagation component is greater than that of the air propagation component, a large reduction effect can be obtained by reducing the vibration by not providing at least one of the ceiling beam, the suspension member, the ceiling rib bolster, and the ceiling rib at a portion having a large amplitude.

The floor-ceiling structure according to claim 3 is a floor-ceiling structure between a floor on an upper layer and a ceiling on a lower layer, and includes: a plurality of floor joists arranged in a specific direction in a state of being arranged substantially parallel to each other; side joists arranged in a position that sandwiches the floor joists from the specific direction in a state of being arranged substantially parallel to the floor joists; an end joist disposed at a position sandwiching the floor joist from a direction orthogonal to the specific direction and fixing end portions of the side joist and the floor joist; and a ceiling support portion for suspending the ceiling from the end joists; wherein at least one joist in a joist group consisting of the side joists and the plurality of floor joists is supported by the wall of the upper or lower floor, and the ceiling support section includes: a ceiling beam disposed across the end joists; a suspension member vertically provided on the ceiling beam; a ceiling rib bolster mounted on the suspension member; and a suspended ceiling rib mounted on the suspended ceiling rib bearer and fixing the ceiling; wherein at least one of the ceiling beam, the suspension member, the ceiling rib support beam, and the ceiling rib is not connected to another member in a region other than the vicinity of the wall.

In the floor-ceiling structure according to claim 3, the floor joists are provided on the end joists substantially in parallel to the side joists in the frame body including the side joists and the end joists. In addition, in the frame body composed of the side joists and the end joists, the ceiling supporting part is arranged on the end joists. At least 1 joist in a joist group consisting of a side joist and a plurality of floor joists is supported by a wall. The ceiling support portion includes ceiling beams, suspension members, ceiling rib bearers, and ceiling ribs, and at least one of the ceiling beams, the suspension members, the ceiling rib bearers, and the ceiling ribs is not connected to another member in a region other than the vicinity of the wall.

Here, when a force acts on the floor to generate vibration, the vibration is transmitted to the frame body composed of the side joists and the end joists. Since at least 1 joist in the joist group is supported by the wall, the vibration of the frame at the position corresponding to the joist supported by the wall is reduced, and the vibration of the part away from the position is increased. Therefore, in the region other than the vicinity of the wall, at least one of the ceiling beams, the suspension members, the ceiling rib support beams, and the ceiling ribs constituting the ceiling support portion is not connected to another member, and thus vibration transmitted from the floor to the ceiling can be reduced. Therefore, the impact sound in a large frequency band can be reduced with a simple configuration. In particular, in such a structure, since the contribution of the solid propagation component is greater than that of the air propagation component, a large reduction effect can be obtained by reducing the vibration without connecting at least one of the ceiling beam, the suspension member, the ceiling rib support beam, and the ceiling rib to another member in a portion having a large amplitude.

The floor-ceiling structure according to claim 4 is a floor-ceiling structure between a floor on an upper layer and a ceiling on a lower layer, and includes: a plurality of floor joists arranged in a specific direction in a state of being arranged substantially parallel to each other; side joists arranged in a position that sandwiches the floor joists from the specific direction in a state of being arranged substantially parallel to the floor joists; an end joist disposed at a position sandwiching the floor joist from a direction orthogonal to the specific direction and fixing end portions of the side joist and the floor joist; and a ceiling support portion for suspending the ceiling from the end joists; wherein at least one joist in a joist group consisting of the side joists and the plurality of floor joists is supported by the wall of the upper or lower floor, and the ceiling support section includes: a ceiling beam disposed across the end joists; a suspension member vertically provided on the ceiling beam; and a suspended ceiling rib mounted on the suspension member and fixing the ceiling; wherein at least one of the ceiling beam, the suspension member, and the ceiling rib is not provided in a region other than the vicinity of the wall.

In the floor-ceiling structure according to claim 4, the floor joists are provided on the end joists substantially in parallel to the side joists in the frame body including the side joists and the end joists. In addition, in the frame body composed of the side joists and the end joists, the ceiling supporting part is arranged on the end joists. At least 1 joist in a joist group consisting of a side joist and a plurality of floor joists is supported by a wall, and the ceiling supporting part comprises a beam for ceiling, a suspension member and a suspended ceiling rib, and at least one of the beam for ceiling, the suspension member and the suspended ceiling rib is not arranged in a region other than the vicinity of the wall.

Here, when a force acts on the floor to generate vibration, the vibration is transmitted to the frame body composed of the side joists and the end joists. Since at least 1 joist in the joist group is supported by the wall, the vibration of the frame at the position corresponding to the joist supported by the wall is reduced, and the vibration of the part away from the position is increased. Therefore, by not providing at least one of the ceiling beams, the suspension members, and the ceiling ribs constituting the ceiling support portion in a region other than the vicinity of the wall, it is possible to reduce the vibration transmitted from the floor to the ceiling. Therefore, the impact sound in a large frequency band can be reduced with a simple configuration. In particular, in such a structure, since the contribution of the solid propagation component is greater than that of the airborne component, a large reduction effect can be obtained by reducing the vibration by not providing at least one of the ceiling beam, the suspension member, and the ceiling rib at a portion having a large amplitude.

The floor-ceiling structure according to claim 5 is a floor-ceiling structure between an upper floor and a lower ceiling, and includes: a plurality of floor joists arranged in a specific direction in a state of being arranged substantially parallel to each other; side joists arranged in a position that sandwiches the floor joists from the specific direction in a state of being arranged substantially parallel to the floor joists; an end joist disposed at a position sandwiching the floor joist from a direction orthogonal to the specific direction and fixing end portions of the side joist and the floor joist; and a ceiling support portion for suspending the ceiling from the end joists; wherein at least one joist in a joist group consisting of the side joists and the plurality of floor joists is supported by the wall of the upper or lower floor, and the ceiling support section includes: a ceiling beam disposed across the end joists; a suspension member vertically provided on the ceiling beam; and a suspended ceiling rib mounted on the suspension member and fixing the ceiling; wherein at least one of the ceiling beam, the suspension member, and the ceiling rib is not connected to another member in a region other than the vicinity of the wall.

In the floor-ceiling structure according to claim 5, the floor joists are provided on the end joists substantially in parallel to the side joists in the frame body including the side joists and the end joists. In addition, in the frame body composed of the side joists and the end joists, the ceiling supporting part is arranged on the end joists. At least 1 joist in a joist group consisting of a side joist and a plurality of floor joists is supported by a wall, and the ceiling support part comprises a beam for ceiling, a suspension member and a suspended ceiling rib, and at least one of the beam for ceiling, the suspension member and the suspended ceiling rib is not connected with other members in the region except the vicinity of the wall.

Here, when a force acts on the floor to generate vibration, the vibration is transmitted to the frame body composed of the side joists and the end joists. Since at least 1 joist in the joist group is supported by the wall, the vibration of the frame at the position corresponding to the joist supported by the wall is reduced, and the vibration of the part away from the position is increased. Therefore, in the region other than the vicinity of the wall, at least one of the ceiling beams, the suspension members, the ceiling rib support beams, and the ceiling ribs constituting the ceiling support portion is not connected to another member, and thus vibration transmitted from the floor to the ceiling can be reduced. Therefore, the impact sound in a large frequency band can be reduced with a simple configuration. In particular, in such a structure, since the contribution of the solid propagation component is greater than that of the airborne component, a large reduction effect can be obtained by reducing the vibration by not connecting at least one of the ceiling beam, the suspension member, and the ceiling rib to another member in a portion having a large amplitude.

Claims

1. A floor-ceiling structure disposed between a floor on an upper layer and a ceiling on a lower layer, characterized by comprising:

a plurality of floor joists arranged in a specific direction in a state of being arranged substantially parallel to each other;

side joists arranged in a position that sandwiches the floor joists from the specific direction in a state of being arranged substantially parallel to the floor joists;

an end joist disposed at a position sandwiching the floor joist from a direction orthogonal to the specific direction, and fixing the side joist and an end of the floor joist, the end joist and the side joist constituting a frame; and

a ceiling beam for suspending the ceiling, the ceiling beam being disposed across the end joists and substantially parallel to the side joists; wherein,

at least one joist in the joist group consisting of the side joists and the plurality of floor joists is supported by the wall of the upper or lower floor,

the ceiling beam is provided only in the vicinity of the wall.

2. The floor-ceiling structure of claim 1,

the joist assembly comprising the side joists and the plurality of floor joists includes a joist supported by the 1 st wall of the upper or lower deck and a joist supported by the 2 nd wall of the upper or lower deck, the 2 nd wall being disposed at a position spaced from the 1 st wall,

the ceiling beam is provided in the vicinity of the wall in the region between the 1 st wall and the 2 nd wall,

the distance from each wall to the ceiling beam in the vicinity of each wall is 1/4 or less of the distance between the 1 st wall and the 2 nd wall.

3. The floor-ceiling structure of claim 1,

the ceiling beam is provided in the vicinity of each wall in the region between the 1 st wall and the 2 nd wall,

the distance from each wall to the ceiling beam in the vicinity of each wall is 1/6 or less of the distance between the 1 st wall and the 2 nd wall.

4. The floor-ceiling structure of claim 1,

the distance from each wall to the ceiling beam in the vicinity of each wall is 1/8 or less of the distance between the 1 st wall and the 2 nd wall.

5. The floor-ceiling structure of claim 1,

at least 5 floor joists are arranged between the 1 st wall and the 2 nd wall,

the ceiling beam is provided in a range from the walls to the 2 nd floor joist.

6. A floor-ceiling structure disposed between a floor on an upper layer and a ceiling on a lower layer, characterized by comprising:

a ceiling support portion for suspending the ceiling from the end joists; wherein,

the ceiling support portion includes:

a ceiling beam disposed across the end joists;

a suspension member vertically provided on the ceiling beam;

a ceiling rib bolster mounted on the suspension member; and

the suspended ceiling rib is arranged on the suspended ceiling rib bearer and is used for fixing the ceiling; wherein,

one, two or three of the ceiling beams, the suspension members, the ceiling rib bearers and the ceiling ribs are provided in regions other than the vicinity of the wall, or the ceiling beams, the suspension members, the ceiling rib bearers and the ceiling ribs are all provided in regions in the vicinity of the wall.

7. A floor-ceiling structure disposed between a floor on an upper layer and a ceiling on a lower layer, characterized by comprising:

the ceiling support portion includes:

a ceiling beam disposed across the end joists;

a suspension member vertically provided on the ceiling beam;

a ceiling rib bolster mounted on the suspension member; and

in the region other than the vicinity of the wall, two or three of the ceiling beams, the suspension members, the ceiling rib bearers, and the ceiling ribs are connected to each other.

8. A floor-ceiling structure disposed between a floor on an upper layer and a ceiling on a lower layer, characterized by comprising:

the ceiling support portion includes:

a ceiling beam disposed across the end joists;

a suspension member vertically provided on the ceiling beam; and

a ceiling rib mounted on the suspension member and fixing the ceiling; wherein,

one or both of the ceiling beam, the suspension member, and the ceiling rib are provided in a region other than the vicinity of the wall, or the ceiling beam, the suspension member, and the ceiling rib are provided in a region in the vicinity of the wall.

9. A floor-ceiling structure disposed between a floor on an upper layer and a ceiling on a lower layer, characterized by comprising:

the ceiling support portion includes:

a ceiling beam disposed across the end joists;

a suspension member vertically provided on the ceiling beam; and

a ceiling rib mounted on the suspension member and fixing the ceiling; wherein,

in the region other than the vicinity of the wall, two of the ceiling beam, the suspension member, and the ceiling rib are connected to each other.