JPH11350435A - Soundproof wall - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the height of a soundproof wall by extending a sound absorbing body upward from the upper end of a soundproof wall main body, and oppositely arranging a sound insulating plate at the prescribed interval in the horizontal direction from the sound absorbing body. SOLUTION: A sound absorbing body 2 is extended upward nearly vertically from the upper end of a soundproof wall main body 1, and a sound insulating plate 4 is fitted to fitting arms 5 provided on stanchions 11 with its upper end portion kept nearly in parallel with the sound absorbing body 2 at the prescribed interval. The sound insulating plate 4 is also fitted to the tilt sections of the fitting arms 5 or on both sides of the soundproof wall main body 1 or on one of the noise source side and the opposite side to the noise source, as required. The lower section of the sound insulating plate 4 is connected to the soundproof wall main body 1, or the interval of the lower section is narrowed to reduce a sound leak from the lower section. The sound entering from above the soundproof wall is multiplex-reflected between the sound absorbing body 2 and the sound insulating plate 4 and multiplex-absorbed by the sound absorbing body 2, thereby noise can be reduced without increasing the height of the soundproof wall.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soundproof wall provided for suppressing the propagation of noise generated from roads, railways, factories and the like.

[0002]

2. Description of the Related Art Heretofore, when the propagation of noise has been suppressed by using a soundproof wall, a method of increasing the height of the soundproof wall has been generally adopted in order to increase the noise reduction effect. However, increasing the height of the soundproof wall has problems such as obstruction of sunshine, deterioration of landscape, and increase in construction cost.
As a method for solving these problems, a method of applying a sound absorbing material to the top end of the soundproof wall (for example, JP-A-50-26316).
Is widely used.

[0003]

However, even with the method using the top end sound absorber, the noise reduction effect at the evaluation point 10 m away from the road is about 2 dB, and a sufficient noise reduction effect has not been obtained.

Accordingly, an object of the present invention is to provide a soundproof wall having an improved noise reduction effect without increasing the height.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a soundproof wall installed around a noise source such as a railway or a road, and extends substantially vertically upward at the upper end of the soundproof wall body. A sound absorber, and a sound insulating plate facing the sound absorber at a predetermined interval in the horizontal direction.

[0006]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, a wall panel 12 is mounted between pillars 11 made of H steel provided at predetermined intervals to form a soundproof wall main body 1.
Is configured. The wall panel 12 is inserted from the upper end between the columns 11 (H steel recess). At the upper end of the soundproof wall main body 1, there is provided a sound absorber 2 extending substantially vertically upward. The sound absorber 2 is formed by attaching a member 22 covered with a film of glass wool to a gutter-like iron plate 21. The sound absorber 2 is attached to a support 11 by bolts 3. Further, a sound insulating plate 4 is provided so that at least an upper end portion of the sound absorbing body 2 is substantially parallel to the sound absorbing body 2 and at a predetermined interval in the horizontal direction.
To provide the sound insulating plate 4, the lower end of the mounting arm 5 is
The sound insulating plate 4 is attached to the mounting arm 5 with the support arm 11.

FIG. 2 shows a simplified side view, in which the horizontal distance between the sound absorber 2 and the sound insulating plate 4 is 0.3 m, and the sound insulating plate 4 is provided only on the vertical portion of the mounting arm 5. The height of the sound insulating plate 4 was 0.5 m. The height of the sound absorber 2 was 0.6 m, and the width thereof was 0.525 m. The distance between the sound insulating plate 4 and the sound absorbing body 2 can be set to 0.5 m, 0.7 m, 1 m, or the like depending on conditions such as the installation location of the sound insulating wall main body 1. Further, the height of the sound insulating plate 4 can also be changed according to the installation conditions and the like.

The embodiment shown in FIG. 3 shows an example in which the distance between the sound absorbing body 2 and the sound insulating plate 4 is 1 m, and the sound insulating plate 4 is also provided at the inclined portion of the mounting arm 5.

In the embodiment shown in FIG. 4, an L-shaped mounting arm 5 is used, and the sound insulating plate 4 is mounted only on a vertical portion thereof.

The embodiment shown in FIG. 5 shows an example in which a sound absorbing material 7 is attached to the inside of a sound insulating plate 4. This sound absorbing material 7 is made of short fibers having a fiber diameter distribution center of 30 denier or less, and has an average apparent density of 0.04 to 0.15 g / cm ^3.
Can be used as the sound-absorbing material 7. As the short fiber material, in addition to synthetic fibers such as polyester, polypropylene, polyethylene, nylon, and vinylon, natural fibers such as wool, cotton, and hemp, or these are used. Mixtures can be used. As the sound absorbing material 7, a fiber sound absorbing material such as rock wool or glass wool, a foamed sound absorbing material such as urethane fall or foam concrete, a material using a granular material such as ceramic or plastic, a perforated plate or the like may be used as appropriate. Can be. Such a sound absorbing material 7 can be stuck not only on one side but also on both sides of the sound insulating plate 4. It is also possible to attach the sound absorbing material 7 only on the surface opposite to that of the embodiment shown in FIG.

The embodiment shown in FIG. 6 shows an example in which the sound insulating plate 4 is provided on the opposite side to the above-mentioned embodiment, that is, on the noise source side, and the sound absorbing material 7 is attached to both surfaces of the sound insulating plate 4. is there.

In any of the above-described embodiments, the sound insulating plates 4 can be provided on both sides of the sound insulating wall main body 1, and may be provided on either the noise source side or the anti-noise source side.

[0014]Example 1  FIG. 2 shows the distance between the sound absorber 2 and the sound insulating plate 4
Was set to 0.5 m. The size of the sound absorber 2 is 0.525 in width.
m and a height of 0.6 m.

[0015]Example 2  In the first embodiment, the height of the sound insulating plate 4 extending in the vertical direction is
The length was doubled to 1 m.

[0016]Example 3  What was shown in FIG. Size of sound absorber 2
Was the same as in Example 1.

[0017]Example 4  FIG. 3 shows the distance between the sound absorber 2 and the sound insulating plate 4
Was set to 0.5 m. The size of the sound absorber 2 is the same as in the first embodiment.
One.

[0018]Example 5  The same sound insulating plate 4 as that shown in Embodiment 4 was used,
Was 0.3 m.

[0019]Example 6  The same sound insulating plate 4 as that shown in Embodiment 4 was used,
Was set to 0.7 m.

[0020]Example 7  The same sound insulating plate 4 as that shown in Embodiment 4 was used,
Was set to 1 m.

[0021]Example 8  A similar sound insulating plate 4 is provided on the opposite side of the fourth embodiment.
Was.

[0022]Example 9  The sound insulating plates 4 of the fourth and eighth embodiments are provided on both sides of the sound insulating wall main body 1.
Was provided.

[0023]Example 10  What was shown in FIG. As the sound absorbing material 7
Using a fiber assembly, the size of the sound absorber 2 was the same as in Example 1.
One.

In the first to tenth embodiments, the right side in the drawings is the anti-noise source side. The soundproof wall main body 1 on the anti-noise source side by the two-dimensional boundary element method according to the first to tenth embodiments.
5 m, 10 m, and 20 m above the ground surface were measured as evaluation points. The sound source side position (speaker installation location) was on the ground surface at a distance of 7.5 m from the soundproof wall main body 1. Further, the height of the soundproof wall in each example was set so that the top of the sound absorbing body 2 was 3 m from the ground surface. 200Hz to 1250
The results of the noise reduction effect obtained by applying a load of road traffic noise in the range of Hz are shown in Table 1 below. Note that the noise reduction effect (dB) is a sound volume reduction as compared to a straight wall having a height of 3 m.

[0025]

[Table 1]

In the fourth to seventh embodiments, the sound absorber 2 of the sound insulating plate 4 is used.
The distances from, were set to 0.5 m, 0.3 m, 0.7 m, and 1 m, respectively. The farther the sound insulating plate 4 is away from the sound absorbing body 2, the greater the noise reduction effect at a distant point, but the closer the point, the greater the sound leakage from the gap. Under these conditions, the distance between the sound insulating plate 4 and the sound absorbing body 2 is preferably about 0.5 m to 0.7 m.

Glass wool is used as the main constituent material of the sound absorber 2, but in addition to glass wool, a fibrous sound absorbing material or a foamed sound absorbing material using an inorganic material such as aluminum fiber or an organic material such as polyester. Alternatively, a sintered body of a granular material, for example, an aluminum sintered body, or a perforated plate such as a porous sound absorber or a perforated polycarbonate plate to which the granular material is welded and adhered can be used. Further, it is preferable that the material used for the sound absorber 2 is protected by a protective material such as a louver or a film as necessary.

When the sound insulating plate 4 is set apart from the sound absorbing body 2, there is a problem that sound leaks from a lower gap. As a method of preventing this, there is a method of connecting the lower part to the soundproof wall main body 1 to prevent sound leakage from the lower part as shown in FIG. In this way, there is no leakage sound from the lower part, and the sound reflected by the sound insulating plate 4 is absorbed by the sound absorber 2, so that there is no problem such as generation of resonance sound. The method of closing the lower portion causes problems such as accumulation of dust such as fallen leaves, snow accumulation, and drainage of rainwater. In order to withstand the snow load, the soundproof wall main body 1 may need to be reinforced. In order to solve this, even if the lower part is not completely closed, the leak of sound from the lower part can be reduced by reducing the interval between the lower parts. That is, as shown in FIG. 5, if the interval between the lower portions is reduced, the sound circulating from the upper portion is multiply absorbed by the sound absorber 2 in the process of multiple reflection between the sound absorber 2 and the sound insulating plate 4. This significantly reduces the sound. Further, by installing the sound absorbing material 7 inside the sound insulating plate 4, the sound reduction effect by the multiple sound absorbing can be improved.

Although a considerable effect can be obtained by providing the sound insulating plate 4 on the side of the noise source, when the sound insulating plate 4 is added also on the side of the noise source, the sound is absorbed by the sound absorbing body 2 and simultaneously the noise is reduced. With respect to the sound source due to the reflection of sound from the source side, it is possible to prevent an increase in sound pressure level on the side opposite to the noise source side sound insulation plate 4. In addition, even when the sound insulation plate 4 is added to the noise source side, even when another sound source exists on the sound receiving point side of the sound insulation plate 4 as in the case where a side road is attached to the highway. By providing the sound absorbing material 7 on the sound receiving point side of the added sound insulating plate 4, it is possible to prevent an increase in sound pressure due to reflection of the additional sound insulating plate 4.

[0030]

As described above, according to the present invention, a sound absorber extending substantially vertically upward at the upper end of the soundproof wall main body, and at least the upper end portion of the sound absorber is provided in a substantially parallel and horizontal direction. Since there is a sound insulation plate provided at intervals, the sound circulating from the upper part of the sound insulation wall is multiple-absorbed by the sound absorber in the process of multiple reflections between the sound absorber and the sound insulation plate, reducing noise Is done.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a preferred embodiment of the present invention.

FIG. 2 is a simplified side view showing an example in which a sound insulating plate is provided vertically.

FIG. 3 is a simplified side view showing an example in which an inclined sound insulating plate is added to a lower end of a vertical sound insulating plate.

FIG. 4 is a simplified side view showing an example using an L-shaped mounting arm.

FIG. 5 is a simplified side view showing an example in which a sound absorbing material is attached to an inner surface of a sound insulating plate.

6 is a simplified side view showing an example in which a sound absorbing material is attached to the opposite side to the example shown in FIG. 5 and to both sides of the sound insulating plate.

FIG. 7 is a simplified side view showing an embodiment in which a lower portion is closed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sound insulation wall main body 2 Sound absorber 4 Sound insulation board

Claims (5)

[Claims] 1. A soundproof wall installed around a noise source such as a railway or a road, comprising: a sound absorber extending substantially vertically upward at an upper end of a soundproof wall main body; A sound insulation wall having a sound insulation plate disposed opposite to the sound insulation plate. 2. The sound insulation wall according to claim 1, wherein the sound insulation plate is provided on one or both of a noise source side and an anti-noise source side. 3. The soundproof wall according to claim 1, wherein a sound absorbing material is attached to at least one surface of the sound insulating plate. 4. The soundproof wall according to claim 1, wherein a distance between the soundproof plate and the soundproof wall main body decreases as the soundproof plate moves downward. 5. The soundproof wall according to claim 1, wherein a lower end of the soundproof plate is connected to a soundproof wall main body.