JP2001003482A - Hollow double sound insulating wall structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase sound insulation performance by effectively reducing the resonance and transmission of sound at a specified frequency. SOLUTION: A specified number of resonance tubes 15 with a specified resonance frequency and a porous sound absorbing material 16 formed of glass wool, rock wool or the like are disposed, as hollow sound insulating material, in a hollow space part S between a pair of wall surface elements 12 and 13 of a double wall. The resonance tubes 15 can take in sound in low frequency band for resonance and absorption by properly setting the lengths of the resonance tubes. Thus, the porous sound insulating material 16 can absorb a sound of relatively high frequency band.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow double sound insulation wall structure provided for effectively absorbing and blocking sound propagation in a building or the like.

[0002]

2. Description of the Related Art Conventionally, a sound insulation wall for minimizing sound propagation between adjacent rooms has a double wall structure, and glass wool and lock are provided in hollow portions defined between wall elements on both sides. What inserts a porous sound absorbing material made of wool or the like is known.

[0003]

However, it has been pointed out that the sound insulation wall having the double wall structure has a low sound insulation performance in a specific frequency band. This is due to the resonance transmission phenomenon.For example, in a dry double wall structure, a wall element such as a gypsum board or a calcium silicate plate is attached to a wooden shaft or a light iron stud with a screw, a nail, a stapler, or the like. Since the resonance transmission frequency shifts to a low frequency range as the surface density of the wall element and the layer thickness of the hollow portion increase, resonance transmission of sound occurs in a low sound range with such a double wall. For example, in the case of a combination of a 65 mm light iron stud and a 12.5 mm + 9.5 mm gypsum board bonded on both sides, which is often used, the sound insulation performance is reduced by resonance transmission at around 90 Hz.

[0004] Even if a porous sound absorbing material such as glass wool or rock wool is inserted into the hollow portion of the double wall, this type of sound absorbing material tends to have a higher sound absorbing coefficient as the frequency becomes higher. Since the sound absorption rate is low in the low frequency band, the effect of preventing resonance transmission of sound in the low frequency range is hardly obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a main technical problem thereof is to improve sound insulation performance by effectively reducing resonance transmission of sound at a specific frequency. It is in.

[0006]

Means for Solving the Problems As a means for effectively solving the above technical problem, a hollow double sound insulating wall structure according to the present invention is provided in a hollow portion between a pair of wall elements in a double wall. A required number of hollow sound absorbing materials having a resonance frequency of? The hollow sound absorbing material takes in a sound in a specific frequency band according to the resonance theory and absorbs the sound by resonance. In this configuration, more preferably, the hollow sound absorbing material is arranged together with the porous sound absorbing material. In this case, the sound in the low sound range, which is likely to be resonantly transmitted through the double wall, can be absorbed by the hollow sound absorbing material, and the sound in the higher frequency band can be absorbed by the porous sound absorbing material. As the hollow sound-absorbing material, for example, an elongated tube having at least one end or an arbitrary portion opened, a resonator having a hole in a part thereof,
A plate-like or film-like vibrator provided with an air layer behind it is suitably employed.

When the hollow sound absorbing material is an elongated tube,
The longer the length and the larger the inner diameter, the lower the resonance frequency (sound absorption frequency). The length of the open tube (open tube) is 開 い of the wavelength of the incident sound.
A resonance phenomenon occurs at the times of 1 ×, 1/3 ×, 2 ×,..., And the length of a tube (closed tube) opened only at one end is １ ／ times the wavelength of the incident sound. , 3/4 times, 5/4 times,...

When the hollow sound absorbing material is a resonator having a hole, the resonance frequency is determined by the spring constant of the air spring formed inside the resonator and the mass of the air mass on the inner periphery of the hole. The larger the mass or cavity volume of the air mass, the more the sound in the low frequency range can be absorbed.

When the hollow sound absorbing material is a plate-shaped or film-shaped vibrating body provided with an air layer behind, the resonance frequency depends on the surface density and rigidity of the vibrating body and the layer thickness of the air layer behind. That is, as the surface density or the air layer thickness of the vibrating body increases, the sound in the low frequency range can be absorbed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment 1] The hollow double sound insulation wall structure shown in the perspective views of FIGS. 1 and 2 is composed of a plurality of light iron studs (LGs) built in a row on a floor slab F at predetermined intervals.
S) 11a, horizontal light iron runner 11b and horizontal rail 11c
A double wall constructed by a dry method is constituted by wall elements 12 and 13 composed of a gypsum board or a calcium silicate plate adhered by screws 14, nails or staples, etc. on both sides of a support member 11 composed of the same. ing. A plurality of resonance tubes 15 and a porous sound absorbing material 16 are built in a hollow portion S sandwiched between the wall elements 12 and 13.

Each resonance tube 15 is located between the light iron studs 11a, 11a of the support member 11, and is fixed to the inner surface of one wall element 12 by an adhesive or other appropriate fixing means. The porous sound absorbing material 16 is made of glass wool, rock wool, or the like, and is fixed to the inner surface of the other wall element 13 by an adhesive or other appropriate fixing means.

The resonance tube 15, which is a hollow sound absorbing material, is open at least at one end or any part thereof, and is made of wood, metal, resin material such as gypsum, vinyl chloride, or the like.
Anything that can constitute a tube may be used. The cross-sectional shape of the tube may be not only circular as shown, but also polygonal, elliptical or the like, and is not particularly limited. Further, the installation direction may be a vertical direction as shown in FIG. 1, a horizontal direction as shown in FIG. When installed obliquely, the resonance frequency can be set to a low frequency band by increasing the length of the tube.

The number of the resonance tubes 15 is appropriately determined by the required sound absorbing power, and the length and inner diameter of the resonance tubes 15 are appropriately determined by the frequency of the sound to be absorbed. That is, FIG.
By providing a plurality of resonance tubes having the same length and inner diameter, the sound absorbing power of a sound in a specific frequency band is increased. In the same (B), a plurality of resonance tubes having the same inner diameter and different lengths are provided. (C) shows that a plurality of resonance tubes having the same length and different inner diameters can be absorbed to absorb sound in a wide frequency band. is there.

In practice, by changing the length as shown in FIG. 3 (B) or by changing the inner diameter as shown in FIG. 3 (C), the resonance frequency can be increased by octaves ( ²ⁿ times) or 1/3. A plurality of resonance tubes different by octaves are combined into one unit, and the plurality of units are arranged in the hollow portion S at predetermined intervals. When the supporting material 11 has a light iron stud 11a and a light iron runner 11b of 65 mm and the wall elements 12 and 13 on both sides are each made of a gypsum board of 12.5 mm + 9.5 mm as generally used, the vicinity of 90 Hz is used. Since the sound insulation performance decreases due to the resonance transmission phenomenon in the center frequency band, for example, the resonance frequencies are set to 63 Hz, 80 Hz, 100 Hz, and 1 respectively.
Four resonance tubes tuned to 25 Hz are combined into one unit.

According to the above configuration, the porous sound absorbing material 16 made of glass wool, rock wool, or the like absorbs and attenuates transmitted sound in the middle and high frequency bands, and is easily transmitted by the resonance transmission phenomenon in a normal double wall structure. Since sound in a low frequency band centered around 90 Hz is absorbed by the units of the plurality of resonance tubes 15, the sound absorption coefficient is improved. In addition, since the resonance frequency of the resonance tube 15 depends on the size and does not depend on the material, it can be easily tuned to a target band by a length or the like.

The resonance tube 15 does not necessarily have to be a straight tube, but may be a curved tube or a bent shape depending on the installation conditions and the like. , The resonance frequency can be set to a low frequency band.

Further, as shown in FIG.
May have holes 15a at appropriate intervals in the length direction. In this case, as is well known,
It can be considered that a cavity 15b corresponding to each hole 15a is partitioned by a virtual partition in the tube, and a plurality of resonators composed of the hole 15a and the cavity 15b are configured.
Each resonator takes in and absorbs sound from the hole 15a, and its resonance frequency is determined by the mass of the air mass existing on the inner periphery of the hole 15a and the spring constant of the air layer in the cavity 15b behind the hole. It can be set freely according to the rule, that is, the size of the holes 15a and their intervals.

[Embodiment 2] The sound insulating wall 1 shown in the perspective views of FIGS. 5 and 6 employs a plate-shaped or film-shaped vibrating body 17 provided with an air layer behind as a hollow sound absorbing material. is there. The vibrating body 17 has an outer peripheral edge stretched around a circular or polygonal frame 18 as shown in FIG. 7, and is fixed to the inner surface of one wall element 12 via the frame 18.
The other parts are basically configured in the same manner as the first embodiment shown in FIGS.

The vibrating body 17 is provided in the resonance tube according to the first embodiment in a band centered on a resonance frequency determined by a surface density and rigidity, a fixing method such as whole circumference fixing or partial fixing, a layer thickness of an air layer behind, and the like. Similarly to 15, the incident sound is absorbed by resonance. Examples of the material of the vibrating body 17 include inorganic materials such as a wooden plate, a metal plate, and a gypsum board.
A synthetic resin plate, or a metal thin film, a thin film made of an inorganic material such as glass fiber, etc., as long as it is plate-shaped or film-shaped, is not particularly limited, but according to the frequency band to be subjected to vibration absorption, the material and thickness, Set the size etc. appropriately. Also,
The number of the vibrating bodies 17 to be installed is appropriately determined depending on the required sound absorbing power.

Therefore, also in this embodiment, by arranging a plurality of vibrators 17 having different materials and sizes as one unit, for example, a sound in a low frequency band centered at, for example, around 90 Hz where resonance transmission phenomenon is likely to occur. Can be effectively absorbed.

Also, in this case, if a hole is formed in the vibrating body 17, a required number of resonators corresponding to the hole can be formed.

In each of the embodiments described above, the double wall is used as the support material 1.
Although the structure is formed by the dry method including the wall elements 1 and the wall elements 12 and 13 attached to both surfaces thereof, the present invention can be similarly applied to a double wall formed by the wet method. In this case, after one wall element is constructed by casting concrete, a hollow sound absorbing material such as a resonance tube 15 or a vibrating body 17 or a porous sound absorbing material 16 is disposed on the back side thereof, and a concrete block is provided. For example, a method of constructing the other wall surface element is adopted. It is also possible to adopt a dry construction method in which a gypsum board or a calcium silicate plate is attached as the other wall element.

In order to minimize the transmission of vibration of one wall element due to receiving sound pressure to the other wall element via the support 11, the support 11 and the wall elements 12, 13 and an elastic body, or the both are connected with a special clip, and a stud (stud 11a)
It is also effective to alternately arrange the element for fixing the wall element 12 and the element for fixing the wall element 13.

[0024]

According to the hollow double sound-insulating wall structure of the present invention, the sound in the low-frequency range, which easily transmits through the double wall, is effectively absorbed by the hollow sound-absorbing material installed inside the double wall. Therefore, it is possible to obtain a hollow double sound insulation wall structure with high sound insulation performance (sound transmission loss) in which sound resonance transmission is reduced and sound insulation loss is eliminated.

[Brief description of the drawings]

FIG. 1 is a first embodiment of a hollow double sound insulation wall structure according to the present invention.
5 is a partial horizontal cross-sectional perspective view showing a case where a resonance tube is installed vertically as a hollow sound absorbing material.

FIG. 2 is a partial vertical cross-sectional perspective view showing a case where the resonance tube is installed horizontally in the first embodiment.

FIG. 3 is a perspective view showing a resonance tube used in the first embodiment.

FIG. 4 is an explanatory diagram showing an operation when an opening is formed in the resonance tube in the first embodiment.

FIG. 5 is a second embodiment of a hollow double sound insulation wall structure according to the present invention.
It is a partial horizontal cross-sectional perspective view showing.

FIG. 6 is a partial vertical sectional perspective view showing the second embodiment.

FIG. 7 is a perspective view showing an example of a vibrating body used in the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sound insulation wall 12, 13 Wall element 15 Resonance pipe (hollow sound absorbing material) 16 Porous sound absorbing material 17 Vibration body S Hollow part

Claims (3)

[Claims] 1. A hollow double sound insulating wall structure, wherein a required number of hollow sound absorbing materials having a specific resonance frequency are arranged in a hollow portion between a pair of wall elements of the double wall. 2. The hollow double sound insulation wall structure according to claim 1, wherein the hollow sound absorbing material is arranged together with the porous sound absorbing material. 3. The plate-like structure according to claim 1, wherein the hollow sound-absorbing material is an elongated tube having at least one end or an arbitrary portion opened, a resonator having a hole in a part thereof, and an air layer provided behind. Or a hollow double sound insulation wall structure characterized by being selected from a film-like vibrator.