JP2003213630A - Noise eliminator of soundproof wall top - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a noise eliminator of a soundproof wall top small-sized and having excellent noise elimination effect by making the best use of a tolerance space at maximum. <P>SOLUTION: In this noise eliminator of a soundproof wall top, at least two sound insulation plates connect the road side and counter-road side top parts in a tolerance space and the top of the soundproof wall, and the tops of the road side sound insulation plate and the counter-road side sound insulation plate are connected by a porous sound absorbing plate. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field relating to a soundproof wall top silencer.

[0002]

2. Description of the Related Art As a measure to prevent the noise barriers of highways and railways from being raised, by installing a muffling device on the top of
A method has been put to practical use to muffle sound waves from a noise source and to increase the soundproofing effect by reducing the sound by reducing the diffraction distance until the sound waves from the noise source diffract at the upper edge of the sound barrier and reach the opposite side of the sound source. However, up until now, the cylindrical shape of the soundproof wall has been the mainstream.

[0003]

As described above, the sound deadening mechanism of the sound deadening wall top muffling device is designed to muffle sound waves from the noise source and the sound waves from the noise source are diffracted at the upper end of the sound deadening wall to oppose the sound source. Due to the sound reduction by increasing the diffraction distance to reach the side. As a sound deadening means for sound waves, a method of covering the surface of the sound deadening device with a sound absorbing material, a method of inserting a sound absorbing material inside, and the like are general. Further, as a method of increasing the diffraction distance of the sound wave, a method of incorporating a sound insulating material inside the silencer is generally used.

By the way, it is hard to say that the cylindrical sound deadening device, which is currently the mainstream, has a sufficient diffraction effect due to the internal sound insulating material in the space allowed by the sound deadening device.

The object of the present invention is to reduce the size of sound by making the most of the diffraction effect of the sound insulation plate incorporated in the top of the soundproof wall muffler and by effectively utilizing the porous sound absorbing plate. It is an object of the present invention to provide a soundproof wall top muffling device having an excellent effect.

[0006]

[Means for Solving the Problems] The size of the three-dimensional space allowed in the soundproof wall top silencer is such that the size (overhang) from the inner surface of the soundproof wall to the inner surface of the road is beyond the vehicle limit, and the outer side of the soundproof wall is outside. As for the overhang, the construction cost is increased due to the increase of the strength of the structure including the soundproof wall by increasing the size of the site by increasing the height of the site and the problem of the sunshine right to the surrounding private houses. Determined by The allowable dimension for a soundproof wall represented by a currently popular cylindrical type is generally within 500 mm as the outer diameter of the cylinder.

[0007] Therefore, as a result of extensive studies conducted by the present inventors, the allowable three-dimensional space is 5 at the top of the soundproof wall.
Assuming a top muffler with a 00 mm square cross section,
In addition to finding a structure in which the sound insulating plate effectively functions in this space, the present invention has been accomplished by finding a compact top muffling device having a superior sound deadening effect by effectively combining a porous sound absorbing plate.

According to a first aspect of the present invention, in a soundproof wall top silencer, at least two of the roadside and the opposite roadside tops in the three-dimensional space allowed by the device are connected to the top of the soundproof wall. With the built-in sound insulation plates (1, 2),
In the soundproof wall top silencer, the tops of the road-side sound insulation plate and the anti-road-side sound insulation plate are arranged so as to be connected by a porous sound absorption plate 3.

According to a second aspect of the present invention, in the soundproof wall top muffling device shown in the first aspect, two sound insulating plates connecting the roadside and antiroad side tops to the top of the soundproof wall are directed to the air. It is a sound-damping wall top muffling device, which is characterized by being expanded.

According to a third aspect of the present invention, an air layer is provided on the sound insulation plate on the road side or the sound insulation plate on the road side and the road side opposite to the sound insulation wall top muffler shown in the first and second embodiments. A soundproof wall top muffling device, characterized in that a porous sound absorbing plate 5 is disposed therethrough.

According to a fourth aspect of the present invention, the soundproof wall is characterized in that the porous sound absorbing plate shown in the first and third aspects is an aluminum fiber type porous sound absorbing plate (3, 5). It is a top silencer.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a soundproof wall top muffler of the present invention will be described in detail with reference to the accompanying drawings.

In the following invention, examples of the porous sound absorbing plate include an aluminum fiber type porous sound absorbing plate, an aluminum foam plate, and an aluminum sintered plate. Glass wool or rock wool is formed into a plate shape with an adhesive. Also included are those formed by molding and foamed plastic into a plate shape.

[Embodiment 1] (Embodiments relating to Claims 1, 3, and 4) FIG. 1 shows an outline of an embodiment of a soundproof wall top silencer of the present invention in a direction perpendicular to the soundproof wall 8. It is shown in a cut sectional view (transverse sectional view). The space allowed for the top silencer, that is, the width (α) and height (β) of the silencer is 5 each.
It was set to 00 mm.

A road-side sound insulation board 1 was formed by connecting the road-side top (X) and the top of the soundproof wall 8 using a galvanized steel sheet having a thickness of 1.6 mm. Further, the anti-road side sound insulating plate 2 is formed by connecting the anti-road side apex (Y) and the soundproof wall apex with the same steel plate as described above.

Further, from the top of the soundproof wall 8 a steel plate similar to the above is used as the structural support plate 4, and in addition a 1.6 mm thick galvanized steel plate is used as a reinforcing plate 6 as shown in the figure. The side sound insulating plate 1, the structure support plate 4, and the anti-road side sound insulating plate 2 were connected.

Further, the road-side sound insulation plate 1 and the anti-road-side sound insulation plate 2
The aluminum fiber type porous sound absorbing plate 3 was attached so as to connect with each other, that is, to connect the point X and the point Y.

On the outside of the road-side sound insulation plate 1, an air layer having a maximum portion of 85 mm was secured, and an aluminum fiber type porous sound absorption plate 5 was attached as shown in the figure. The sound absorbing plate 5 was supported by a reinforcing plate 6 similar to the above as shown in the figure.

On the outside of the sound insulating plate 2 on the opposite road side, a plate thickness of 0.
The decorative plate 7 was made of aluminum-based punching metal having a diameter of 8 mm and an aperture ratio of 50%. The shape is symmetrical with the aluminum fiber-based porous sound absorbing plate 5 and is supported by the reinforcing plate 6.

FIG. 2 shows a perspective view from the road side for explaining the structure of the soundproof wall top muffler 9 of this embodiment. The length of one unit of the soundproof wall top silencer 9 is 150
It was set to 0 mm. Soundproof wall top silencer grip 10 in the figure
Is a portion for inserting and gripping the H-shaped steel, which serves as a structural support of the soundproof wall 8, into the recessed portion. This grip has
A 1.6 mm thick galvanized steel plate was used.

A field test was conducted for the purpose of confirming the effect of the soundproof wall top muffling device 9 of the present invention. FIG. 6A shows the outline of the field test. First, as a comparative example,
A pair of 15 mm-thick resin soundproof walls having a height of 3.3 m and a plate thickness of 5 mm were installed with a length of 30 m and an interval of 15 m. The speaker 16 was installed at a position 0.5 m high in the center. In addition, microphones 17 were installed at two measurement points (P1 / P2) having a height of 1.2 m at positions of 5 m and 10 m from the soundproof wall. 500Hz, 1000
Hz and 2000 Hz 1/1 octave band noise was generated from the speaker 16 and used as a test sound source. The strength of the test sound source was adjusted to be 100 dB at 1 m in front of the speaker, and the resin sound barrier 1
The sound insulation effect of 5 was confirmed.

Next, as an example, FIG. 6 (b) shows a field test procedure when the soundproof wall top muffler 9 of Example 1 of the present invention is installed. The total height in this case is 3.3 m, which is the same as the soundproof wall height of the comparative example of (a). The noise reduction effect of the noise barrier top muffler 9 is measured at each measurement point (P
It was determined by subtracting the sound pressure level (dB) of the example from the sound pressure level (dB) of the comparative example at 1 / P2), and these are summarized in Table 1.

[0023]

[Table 1]

As is clear from Table 1, the effect of the soundproof wall top muffling device 9 of the present invention is that P at 5 m from the soundproof wall is effective.
2.5 to 8.7 dB at one point, and 10 from the soundproof wall
A noise reduction effect of 1.8 to 6.0 dB was observed at point P2 at point m.

The decorative plate 7 made of punching metal, which is used on the outside of the sound insulating plate 2 on the opposite road side, replaces the punching metal with an aluminum fiber-based porous plate when the reverberant noise generated from the sound source on the opposite road side is large. Use of the sound absorbing plate enhances the effect as a muffling device.

In the case of use as a decorative plate, the sound insulating plate 2 on the side opposite to the road may be processed into a shape similar to that of the punched metal decorative plate 7 to serve as a decorative plate and a sound insulating plate.

However, when used in combination with a soundproof wall made of transparent polycarbonate in the median strip of an expressway, the aluminum fiber type porous sound absorbing board 5 is provided outside the sound insulating boards (1, 2) with an air layer interposed therebetween. It is more effective to reduce noise by disposing.

[Example 2] (Examples relating to Claims 2, 3 and 4) A roadside side and an anti-noise side of a sound deadening device having the same structure as the sound deadening wall top muffling device having the same structure as that of the first embodiment. FIG. 3 shows a cross-sectional view of a sound deadening device having an expansion part 11 in which two sound insulating plates (1, 2) connecting the top part on the road side and the top part of the soundproof wall are expanded by 50 mm into the air.

In order to confirm the effect of the soundproof wall muffler of the present invention, a field test was conducted in the same manner as in the procedure of Example 1, and the results are shown in Table 2.

[0030]

[Table 2]

As is clear from Table 2, by using the soundproof wall top muffling device of the present invention, the sound reduction effect more than the effect obtained by the method of the first embodiment was recognized.

It should be noted that the extension portion 11 in this embodiment has 50
However, if the partial expansion is allowed in relation to the surrounding environment, the expansion is not limited to 50 mm, and the expanded part is preferably large from the viewpoint of the sound reduction effect.

In addition, when the extension to the road side is not permitted and the opposite road side is permitted, the length of the extended portion may be determined within a range allowable on the opposite road side.

As is clear from the present embodiment, the sound insulation plate disposed inside is extremely expanded to the outside without increasing the main body portion of the soundproof wall top silencer, that is, the width and height. It is possible to enhance the sound reduction effect economically with a simple method.

The inventors of the present invention filed Japanese Patent Application No. 2001-35.
No. 4354, a silencer in which a plastic bottle is filled in a cylindrical silencer top silencer is pending.
By adopting the structure shown in FIG. 4 and FIG. 5 also in the soundproof wall top muffler of the present invention, the PET bottle can be utilized as a sound absorbing auxiliary material.

[0036]

As described above in detail, the sound insulating plates (1 and 2) are arranged inside the device to maximize the use of the space allowed for the sound deadening device at the top of the soundproof wall, and the diffractive effect thereof is provided. By making maximum use and by effectively using the aluminum fiber-based porous sound absorbing plates (3, 5), it is possible to obtain a soundproof wall top sound deadening device having a small size and excellent sound deadening effect.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating the basic structure of a soundproof wall top silencer.

FIG. 2 is a perspective view illustrating the basic structure of the soundproof wall top muffling device as viewed from the road side.

FIG. 3 is a transverse cross-sectional view for explaining the basic structure of the device when two sound insulating plates arranged inside the soundproof wall top muffling device are expanded toward the air.

FIG. 4 is a transverse cross-sectional view for explaining the basic structure of the soundproof wall top silencer when a PET bottle is mounted inside the apparatus.

FIG. 5 is a plan view showing a state in which the aluminum fiber-based porous sound absorbing plate on the top of the soundproof wall top muffling device is removed and the bird's-eye view is viewed from directly above.

FIG. 6 is a diagram showing a field test implementation point of a soundproof wall top muffling device, (a) is a case without a soundproof wall top muffling device (comparative example), and (b) is a soundproof wall top muffling device. It is a figure in a case.

[Explanation of symbols]

1 Roadside sound insulation board 2 Anti-road side sound insulation plate 3 Porous sound absorbing plate 4 Structure support plate 5 Road side porous sound absorbing board 6 Reinforcement plate 7 Veneer 8 sound barriers 9 Sound barrier top muffler 10 Soundproof wall top silencer grip 11 Sound insulation plate extension 12 partition boards 13 PET bottles 14 Connection strip 15 resin soundproof wall 16 speakers 17 microphone Width of α silencer β Height of silencer X Road side top Y Road side apex P1 measurement point P2 measurement point

Continued front page    (72) Inventor Masamichi Sekiya             2-2-1 Jonanjima Stock Market, Ota-ku, Tokyo             Company Unix (72) Iwao Ishii, inventor             2-2-1 Jonanjima Stock Market, Ota-ku, Tokyo             Company Unix (72) Kenji Ihara             2-2-1 Jonanjima Stock Market, Ota-ku, Tokyo             Company Unix F-term (reference) 2D001 AA01 BA01 CA02 CB05 CC01                       CD02                 5D061 AA16 BB35 BB37 DD06

Claims (4)

[Claims] 1. A soundproof wall top muffling device has at least two sound insulating plates for connecting the roadside and anti-roadside tops in a three-dimensional space allowed by the device and the top of the soundproof wall. In addition, a soundproof wall top muffling device, wherein the road-side sound insulation plate and the anti-road-side sound insulation plate are arranged so that the tops thereof are connected by a porous sound absorption plate. 2. The soundproof wall top muffler according to claim 1, wherein two sound insulation plates connecting the roadside and antiroad side tops and the soundproof wall top are expanded toward the air. , Sound deadening device on top of sound barrier. 3. A porous sound absorbing plate is disposed on the road-side sound insulating plate or the road-side and anti-road side sound insulating plate of the soundproof wall top silencer according to claim 1 or 2, with an air layer interposed therebetween. A sound deadening device on the top of a soundproof wall. 4. A soundproof wall top sound deadening device, wherein the porous sound absorbing plate according to claim 1 or 3 is an aluminum fiber type porous sound absorbing plate.