JP4736437B2 - Sound insulation double ceiling structure - Google Patents

Description

  The present invention relates to a sound insulation double ceiling structure in an apartment house or the like.

  In general, in apartment buildings of concrete buildings, a double ceiling structure is used for wiring the lighting and power supply to the ceiling. However, in order to secure a wide indoor space, the pocket (space between the ceiling plate and the ceiling slab) is as much as possible. It is necessary to have a narrow double ceiling. At this time, when a double ceiling with a small pocket (about 300 mm or less) is formed on the ceiling slab, and a gypsum board is installed as a ceiling material, a resonance transmission phenomenon occurs due to the influence of the pocket air, and a heavy floor impact sound insulation performance test In (JIS A 1418-2), the sound insulation performance in the low sound range (mainly 63 Hz) deteriorates.

  Here, as shown in the in-house heavy floor impact sound insulation performance test results shown in FIGS. 4 (a) and 4 (b), the double ceiling using gypsum board as the ceiling board improves the sound insulation performance in the middle and high sound ranges. To do. However, in the double ceiling using the gypsum board, the sound insulation performance is deteriorated in the low sound range (particularly, the determination frequency of the heavy floor impact sound level is 63 Hz) in the heavy floor impact sound level measurement by the above-described insulation performance test. This is presumably because the deterioration of the sound insulation performance in the low sound range is caused by a resonance phenomenon between the air spring portion of the double ceiling space and the mass portion of the gypsum board.

  In addition, the effect of ceiling depth (improvement based on the absence of double ceiling) is -3 dB at a depth of 100 mm, approximately -1 dB at 200 mm, and 4 dB at 300 mm. There is a report (Non-patent Document 1) that adversely affects the low frequency range (63 Hz) when taken small (FIG. 5).

Because the ceiling air layer forms a kind of elastic body, the ceiling slab and the ceiling plate sandwiching this air layer form one resonance system, and the vibration of the ceiling slab travels through the air layer and the ceiling plate. Shaking and impact sounds are generated. The resonance frequency f _d (Hz) at this time is such that the thickness of the air layer is d (m), the surface density of the slab is m ₁ (kg / m ² ), the density of the ceiling plate is m ₂ (kg / m ² ), When the speed of sound is c (m / s) and the density of air is ρ (kg / m ³ ), it is expressed by the following formula 1. Here, since m ₂ << _{1 in} general, f _d enters the audible frequency region when the air layer d is small, and adversely affects the heavy floor impact sound.

  Therefore, conventionally, in order to enhance the sound insulation effect, (1) deepening the ceiling pocket (no more than about 300 mm), (2) interposing a sound absorbing material such as glass wool, (3) such as runner part Measures such as attaching rubber to the place where the slab is installed and insulating it were taken. Patent Document 1 describes a sound insulation structure for a building structure in which a sound absorber is provided in an air layer between a housing and a finishing material to suppress resonance transmission. Patent Document 2 discloses a soundproof ceiling structure in which a ventilation material is provided on a ceiling slab and a sound absorbing material is disposed. Patent Document 3 forms an air layer having an opening between a panel surface and a wall surface, thereby forming a slit. An acoustic chamber structure that constitutes a type resonator and absorbs low frequencies is disclosed.

Summaries of Annual Meetings of the Architectural Institute of Japan (Tokai), September 2003; Yukinori Fuse “Effects of Double Ceiling on Weight Impact Sound—Part 2 Laboratory Examination” JP 2001-152571 A Japanese Patent Laid-Open No. 10-311106 JP-A-6-57850

  However, if the ceiling of the double ceiling structure is taken deep as in the above prior art, the indoor space becomes narrow, and the sound absorption effect by the sound absorbing material is effective in the high sound range, but it is difficult to improve the sound insulation performance in the low sound range. There is a problem that. In addition, even if the runner part is insulated, the floor impact sound is not a solid propagation sound but an air propagation sound, so the sound insulation effect cannot be obtained, and the structure with slits as openings makes the construction complicated There is. Furthermore, even when a double floor is constructed on the upper floor, there is a problem that the floor floor and the floor slab (corresponding to the ceiling slab) resonate to deteriorate the heavy floor impact sound insulation performance.

From Formula 1, for example, an air density ρ = 1.293 kg / m ³ and a sound velocity c = 343.5 m are passed through a 200 mm thick slab (surface density m ₁ = 460 kg / m ² ) through an air layer with a thickness d = 100 mm. / S, and when a gypsum board having a thickness of 12.5 mm (surface density = 8.4 kg / m ² ) is used as the ceiling board, the resonance frequency f _d is calculated to be 68.4 Hz. In reality, it is thought that the resonance of the ceiling board acts and the resonance occurs at a frequency in the vicinity of this, so the resonance frequency determines the performance in the heavy floor impact sound insulation performance test (JIS A 1418-2). There is a problem that it falls within the frequency band of 63 Hz and deteriorates the performance.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a sound-insulating double ceiling structure having excellent sound insulation performance.

In order to solve the above technical problem, as shown in FIG. 1, the present invention provides a double ceiling structure in which a ceiling plate 8 is attached below the ceiling slab 2, and is provided between the ceiling slab and the ceiling plate 8. The space between the air layers 4 is 300 mm or less, and the surface density of the ceiling plate is 3 kg / m ² or less.

In the sound-insulating double ceiling structure according to the present invention, the ceiling plate is composed of a flat plate material having a thickness of 20 mm or less.
Moreover, the sound insulation double ceiling structure which concerns on this invention is the structure which made the space | interval of the said air layer 100 mm or less.

  In the sound-insulating double ceiling structure according to the present invention, the ceiling slab is constituted by an upper double floor.

  In the sound-insulating double ceiling structure according to the present invention, the ceiling panel has a configuration in which a non-combustible plate material or a non-combustible flexible material is attached to one or both of the front surface and the back surface.

According to the sound-insulating double ceiling structure according to the present invention, in the double ceiling structure in which a ceiling plate is attached below the ceiling slab, an air layer interval between the ceiling slab and the ceiling plate is set to 300 mm or less, and the ceiling Since the board has a surface density of 3 kg / m ² or less, a good sound insulation effect can be obtained even if the pocket is narrow, and the sound insulation performance against heavy impact sound (around 63 Hz) in the low range on the floor is excellent. There is.

  According to the sound-insulating double ceiling structure according to the present invention, since the ceiling plate is made of a flat plate material having a thickness of 20 mm or less, there is an effect that a good sound insulation effect can be obtained with a practical shape. Moreover, according to the sound insulation double ceiling structure which concerns on this invention, since the space | interval of the air layer was 100 mm or less, there exists an effect that the indoor space with a high ceiling can be ensured.

  Moreover, according to the sound insulation double ceiling structure which concerns on this invention, even if the floor which comprises a ceiling slab is a double floor, there exists an effect that a favorable sound insulation effect is acquired.

  According to the sound-insulating double ceiling structure according to the present invention, the ceiling panel has a configuration in which a non-combustible plate material or a non-combustible flexible material is attached to one or both of the front surface and the back surface. There is an effect that a ceiling is formed.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a sound insulation double ceiling structure according to the present invention will be described with reference to the drawings.
FIG. 1 is an exploded perspective view of the sound-insulating double ceiling structure employed in a living space such as a housing complex. As shown in FIG. 2, this ceiling structure has a ceiling base material 6 disposed below a concrete air slab 2 from a concrete ceiling slab 2, and a ceiling plate 8 is provided on the lower surface of the base material 6. It has a double ceiling structure.

  In the living space, a runner material 10 having a U-shaped cross section is provided on a wall surface of a room (plane 5675 mm × 3340 mm), and a ceiling serving as a base material 6 having a cross-section of a U shape is provided between the runner materials 10. The edge material is installed at regular intervals (for example, 303 mm). Then, the ceiling plate 8 is fixed to the lower part of the base material 6. Here, in the ceiling pocket between the ceiling slab 2 and the ceiling plate 8, an air layer 4 having a predetermined pocket interval (h) is formed.

As described above, a gypsum board having a thickness of 12.5 mm (surface density = 8.4 kg / m ² ) is used as the ceiling plate 8 to a slab having a thickness of 200 mm (surface density m ₁ = 460 kg / m ² ) and a thickness d. In the case of being arranged through an air layer of 100 mm, the resonance frequency f _d is 68.4 Hz from Equation 1. When a heavy gypsum board is used as the ceiling board in this way, the resonance frequency falls within the 63 Hz band, which is the frequency that determines the performance in the heavy floor impact sound cutoff performance test (JIS A 1418-2), and the performance deteriorates. Let

On the other hand, when a glass wool board (surface density = 1.28 kg / m ² ) having a thickness of 20 mm is arranged as the ceiling board 8 under the same conditions as the gypsum board, the resonance frequency f _d is 174 Hz from Equation 1. Calculated. Further, assuming that a surface material (for example, a heat insulating material (hard urethane foam) having a surface density of 0.45 kg / m ² ; manufactured by Achilles Co., Ltd.), which is much lighter than the plaster board, is used for the ceiling plate, the resonance frequency can be calculated from the above Equation 1. f _d is about 300Hz.

  Thus, it is expected that the use of a lightweight face material as the ceiling plate 8 will shift the resonance frequency and prevent the sound insulation performance from being deteriorated. From this, the resonance frequency band becomes the determining frequency of the heavy floor impact sound insulation performance, 63 Hz. It is considered that deterioration due to resonance of slab vibration can be prevented.

For this reason, with respect to the double ceiling structure, a heavy floor impact sound blocking performance test was performed in-house on a ceiling plate with a low surface density (test bodies 1 to 3) and a ceiling plate with a high surface density (gypsum board). Here, the measurement of the heavy floor impact sound level is based on JIS A 1418-2 (Measurement method of floor impact sound insulation performance of buildings-Part 2: Method using standard weight impact source). -2 (Evaluation method of sound insulation performance of buildings and building components-Part 2: Floor impact sound insulation performance) Moreover, the test bodies 1-3 consist of glass wool boards with a plate thickness of 20 mm to 25 mm. In addition, as a plate material having a low surface density (3.0 kg / m ² or less), there are a heat insulating material made of rigid urethane foam, a phenol foam, and an olefin-based rigid foam.

The heavy floor impact sound was set to 63 Hz, which is the frequency for determining the heavy floor impact sound level in the low frequency range. For ceiling plate 8 has a lighter areal density (3.0 kg / m ² or less) specimens 1-3, the surface density of the heavy (3.0 kg / m ² or more) were compared separately to the gypsum board. Further, assuming a double ceiling with a narrow ceiling, the gap (h) as the air layer 4 was set to 100 mm.

The surface density, each specimen 1 1.28 kg / m ^2, test material 2 is 1.6 kg / m ² and specimen 3 is 2.4 kg / m ^2. The surface density of each of the three types of gypsum board tested together was 4.7 kg / m ^{2 for} a gypsum board having a thickness of 7 mm, and 6.4 kg / m ^{2 for} a gypsum board having a thickness of 9.5 mm. The 2 mm gypsum board is 8.4 kg / m ² .

  FIG. 3 shows the amount of improvement based on the ceiling of the ceiling slab surface (no ceiling plate) as a result of the heavy floor impact sound test. FIG. 3A is a table showing a comparison result of the improvement amount in the difference in areal density, and FIG. 3B is a graph showing the improvement amount.

According to this result, for test bodies 1 to 3 (surface density of 1.28 kg / m ^{2 to} 2.4 kg / m ² ) having a surface density of 3.0 kg / m ² or less, test bodies 1 and 2 are improved. Of 0.7 dB and 0.0 dB are obtained, and the improvement amount of the test sample 3 is slightly reduced to -0.3 dB, and a good sound insulation performance is obtained. It was verified that there was no effect on the impact sound insulation performance. On the other hand, for a gypsum board having a surface density of 3.0 kg / m ² or more (surface density 4.7 kg / m ^{2 to} 8.4 kg / m ² ), the improvement is −0.8 dB to −2.4 dB. It has been verified that it has an influence on the weight impact sound blocking performance.

From these, in the double ceiling structure using the ceiling board 8 made of a material having a surface density of 3.0 kg / m ² or less, a practical and effective sound insulation effect can be expected for a heavy impact sound (63 Hz). It can be judged.

  Next, an in-house heavy floor impact sound insulation performance test was conducted in a state in which a double floor for sound insulation was constructed on the upper floor (which comprises a downstairs ceiling slab). Normally, many sound insulation double floors are laid on the floors of apartment buildings, and the floor impact sound insulation performance of the downstairs ceiling structure where such double floors were laid was measured.

The ceiling structure in this case is the same as the double ceiling structure, and the test conditions are the same as in the in-house test. However, in this study, as top plate 8, the surface density is light face material and a surface density of (0.54 kg / m ²⁾ was performed for the two types of heavy gypsum board (8.4kg / m ^2). The double floor has a floor height from the floor slab to the floor board of 150 mm. In order to confirm the frequency characteristics, the impact frequency was 31.5 Hz to 4 kHz.

  FIG. 4 shows the amount of improvement based on the ceiling of the ceiling slab surface (no ceiling plate) as a result of the heavy floor impact sound test. FIG. 4A is a table showing the comparison results of the improvement amounts in the difference in impact frequency for the above two types of surface density ceiling boards, and FIG. 4B is a graph showing the improvement amounts. .

According to this result, if construction is carried out using a ceiling plate made of a face material with a low surface density (3 kg / m ² or less), there will be little effect on the heavy floor impact sound insulation performance in the low range where the impact sound is 63 Hz or less. . For this reason, even when a double floor is constructed on the upper floor, it can be judged that it is effective to use a surface material having a low surface density (3 kg / m ² or less). In addition, a nonflammable plate material or a nonflammable flexible material (such as a glass nonwoven fabric) may be attached to one or both of the front and back surfaces of the ceiling plate, thereby obtaining a ceiling excellent in fire resistance.

Therefore, according to the ceiling structure according to the above-described embodiment, the ceiling panel has a surface density of 3 kg / m ² or less even though the ceiling pocket of the apartment building of the concrete building is within 300 mm. It is possible to provide a double ceiling that can prevent the loss of nearby low sound range, and also has the effect of widening the indoor space. Furthermore, since the ceiling plate is a plate having a surface density of 3 kg / m ² or less, the ceiling plate can be cross-finished and is excellent in aesthetics. In addition, the double ceiling structure in which a nonflammable material is attached to the front and back surfaces of the ceiling board is excellent in fire resistance.

It is a disassembled perspective view of the double ceiling structure which concerns on embodiment of this invention. It is a figure which shows the double ceiling structure which concerns on embodiment, (a) shows the whole cross section, (b) shows the cross section of a part (A). (A) is a table | surface which shows the comparison result of the improvement amount in a difference in areal density about the result of a heavy floor impact sound test, (b) is a graph which shows the improvement amount. Regarding the results of the heavy floor impact sound test, (a) is a table showing a comparison result of the improvement amount in the difference in the impact frequency for the ceiling boards of two types of areal density, and (b) is a graph showing the improvement amount. It is. This is an excerpt from the summary of the annual meeting of the Architectural Institute of Japan, Yukinori Fuse, “Effects of double ceilings on weight impact sound—part 2: Examination in the laboratory”.

Explanation of symbols

2 Ceiling slab 4 Air layer 8 Ceiling board

Claims (3)

In a double ceiling structure in which a ceiling board is attached below the ceiling slab, the thickness of the air layer between the ceiling slab and the ceiling board is 100 mm or less, and the surface density of the ceiling board is 1.28 kg / m ² to 2. A sound-insulating double ceiling structure characterized in that the thickness is 4 kg / m ² and the thickness of the ceiling plate is 20 mm to 25 mm . Sound insulation double ceiling structure according to claim 1 Symbol mounting, characterized in that the ceiling slab is constituted by an upper floor of a double bed. The ceiling plate, on one or both front and back surfaces, according to claim 1 or 2 Symbol placement of sound insulation double ceiling structure, characterized in that deposited the incombustible sheet material or incombustible flexible material.

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