JPH1113026A - Silencing wall - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a phase difference between the projected sound of noise and the reflected sound for silencing by fitting a sound absorbing board, a bulkhead board, and rib-shaped sound absorbing boards on the bulkhead board of a box-like wall body partitioned by a bulkhead board at the inner lower section, and fitting a sound absorbing board provided with a curved surface at one end in the longitudinal direction of the sound absorbing board. SOLUTION: A bulkhead board 2b is fitted and fixed at the inside lower section of a wall body 1, a sound absorbing board 3b is fitted and fixed on it, a bulkhead board 2t is installed, a plurality of rib-like sound absorbing boards 4 are provided in the vertical direction of the sound absorbing board 3t, and a curved surface 5' is formed on one side. When the projected sound is fed to chambers formed by the upper bulkhead 2t, a part of the incident sound becomes the diffracted wave, it enters the chambers formed by the lower sound absorbing board 3b and the lower bulkhead 2b as the diffracted wave, and a phase difference is generated between it and the next incident sound wave. The phase difference between them has an interference effect, and the sound wave is eliminated or damped. The rib-like sound absorbing boards 4 arc inclinatorily erected at the angle of about 30 deg. in the proceeding direction, for example, and the projected sound is scattered by the vortexes generated on the tip back faces of ribs damp noise.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound-absorbing wall that stands on a bullet train, a highway, or a high-traffic road, and that is soundproof.

[0002]

2. Description of the Related Art Generally, a soundproof wall is formed of a metal plate as a package. In the package, glass wool is filled into a bag made of polyethylene, polyvinyl, etc., and the bag is decorated, and the surface of the package is covered with a door made of a metal plate. It is the present situation that a soundproof wall is formed.

[0003]

However, the soundproofing by this method has not been expected to provide the effect of the soundproofing wall in the present situation. In the motorway, since the size of the automobile and the traffic volume increase extremely and the generated noise energy is strong, it is impossible to cope with the conventional sound absorption and sound insulation alone. In addition, in the Shinkansen track, the number of trains to be transported has been increased for mass transportation, and the speed has been increased.
The generated energy of the vibration noise becomes strong and the wind pressure becomes strong, so that the glass fiber mat of the sound absorbing material installed in the soundproof wall becomes powder in a short time, and the sound absorbing effect is lost. There are a number of drawbacks. The noise barrier installed on the Shinkansen has a limited height. Its height is up to the height of the vehicle window. This is not just a matter of visibility. If visibility is a problem, even if the soundproof wall is raised, the Shinkansen vehicle can be operated at high speed if the transparent portions (transparent plastic soundproof wall) are erected at required intervals, and the visibility is wide because the track width is narrow. This is the same principle as that a disc can be seen through by rotating a disc with a plurality of holes. The higher the noise barrier, the better the soundproofing effect,
The Shinkansen has a narrow track and high wind pressure. In addition, in the case of an overpass, it is difficult to make a foundation for erecting the soundproof wall high.
In addition, depending on the direction in which the gust is received, the wind pressure applied to the soundproof wall becomes strong and involves great danger. Therefore, it is particularly desirable that the soundproof wall of the Shinkansen has a low wall surface and a good soundproof effect.

[0004]

In order to achieve the above object, the soundproofing wall according to the present invention is a conventional soundproofing method in which a sound absorbing material is provided inside a wall formed of a metal plate and a sound absorbing material is provided. The effect of the interference between sound waves and sound waves, that is, the formation of a phase difference (also referred to as an anti-phase) between the projected sound of the generated noise and the sound waves reflected by the projected sound waves in the wall, causing the two to interfere with each other. And the effect of controlling the flow of air to generate a vortex, which scatters sound waves to prevent diffraction waves. In addition, the wall surface is formed three-dimensionally so as to enlarge the sound absorbing surface. Further, a curved surface is provided on the upper portion of the wall surface which is erected, and a vortex is generated at the back of the tip of the curved surface, and the vortex scatters a diffracted wave sound diffracting the top of the wall body, thereby providing a diffraction sound. A sound-absorbing wall characterized by soundproofing by a combined effect of preventing noise.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the following embodiments. FIG. 1 is an external front view of a sound deadening wall according to the present invention, and FIG. 2 is a cross-sectional view taken along a line AA. FIG. 3 shows a minor section, and FIG. 4 shows a part of the minor section in detail. 5, 6, 7, and 8 show in detail the assembly structure of the sound deadening wall of the present invention. FIG. 8 shows a state in which a partition plate 2 b is fitted and fixed to the lower inside of the wall body 1, and The sound-absorbing plate 3b is fitted and fixed by applying a vibration-proof and sound-proof paint, and the partition plate 2t is placed thereon. A vibration-proof and sound-proof paint is applied to the entire inner surface of the partition. A plurality of rib-shaped sound-absorbing plates 4 are provided on the sound-absorbing plate 3t at required intervals in the vertical direction, and a composite sound-absorbing plate 3t having a curved surface formed on one side is provided. FIG. 9 shows a protection plate for fixing the back of the curved plate.

FIG. 10 is a front view showing the entire sound-absorbing wall of another structure (FIGS. 11 to 13). This sound deadening wall has a structure provided with a sound absorbing plate in which only the upper sound absorbing plate is formed of a single plate. This is economical because the processing can be performed easily and the processing cost is low. Although the soundproofing effect is slightly inferior to that of FIG. 1, the soundproofing wall has a much better soundproofing effect than a general soundproofing wall.

In FIGS. 14 and 15, only the curved portion is detachably formed. This is because processing is simple to form a curved rib-shaped sound absorbing plate in the curved portion. This is because it is extremely difficult to form the curved sound absorbing plate and the curved sound absorbing plate in an integrated structure. If only the curved portion is used, plastic molding can be relatively easily performed. Therefore, a split structure is preferable. FIGS. 16 and 17 are overall views of a sound deadening wall in which a curved rib 4 and a vertical rib 4 are integrally formed. FIG. 18 is a sectional view. FIG. 19 is a view macroscopically showing the relationship between sound waves and sound absorbing holes of a sound absorbing plate provided on a sound deadening wall according to the present invention. Next, the operation principle of the soundproofing of the present invention will be described with reference to the drawings. FIG. 1 is a front view of a sound absorbing wall, and 3t is an upper composite sound absorbing plate (a sound absorbing plate formed by forming a plurality of holes in a composite plate in which a sound absorbing material is interposed between metal plates. The rib-shaped sound absorbing plate 4 is installed upright on the surface of 3t. The rib to be attached is attached with an inclination (preferably having an inclination of about 30 degrees with respect to the wall surface) in the traveling direction when the soundproof wall is erected on the Shinkansen track. As shown in FIGS. 5 to 9, the partition wall plate 2 b is fitted and fixed to the lower part of the inside of the wall body 1 as shown in FIGS.
The vibration-proof and sound-insulating material, ie, Japanese Patent Publication No. Sho 6
The application of the name of the invention of 2-58633 is preferred. This is because this paint has no frequency characteristics, that is, it has a soundproofing effect for all frequency sounds. Next, the sound-absorbing plate 3b is mounted on the partition wall, and the partition wall plate 2t is further mounted on the fixed partition wall, and the vibration-proof and sound-proof paint is applied to the partition wall plate 2t, the sound absorbing plate 3b, and the entire upper part of the wall. I do. A sound absorbing plate 3t formed by erecting a rib-shaped sound absorbing plate is mounted on the mounted partition plate 2t and the wall 1, and fixed on the partition 2t and the upper portion of the wall 1. The protection plate 6 of the curved portion provided on the upper sound absorbing plate 3t is formed as shown in FIG. 9 and is attached to one side of the wall body 1 and fixed to the back surface of the curved portion by being attached thereto. As shown in FIG. 3, the front surface of the curved portion is preferably structured such that the curved end portion and the end portion of the rib-shaped sound absorbing plate 4 erected on the wall surface are connected and fixed by a bracket 7. This is for reinforcement. The sub-section of the soundproof wall having the above structure will be described in more detail with reference to FIG. As described above, the inside of the wall body 1 includes the partition plates 2t and 2b and the sound absorbing plates 3t and 3t.
b, a plurality of upper and lower chambers are formed in a plurality of chambers. Through holes through which sound waves enter and exit are formed in the sound absorbing plates 3t and 3b, and details thereof are shown in FIG.

Next, the operation principle of the soundproof effect in which the soundproof walls having the above structure are provided on both sides of the Shinkansen track will be described in detail with reference to the drawings. The Shinkansen runs at 220 km / h.
This is a speed of 61 m / s, so that the standing soundproof wall is instantaneously subjected to a corresponding wind pressure. The generated noise induces a kind of Doppler effect by the wind pressure, and the noise increases. That is, the sound pressure energy becomes strong. Therefore, the sound-absorbing material (glass fiber) contained in the conventional sound-insulating wall and contained in a polybag becomes powder due to the wind pressure and the sound pressure, and the soundproofing effect is not expected. It is also because the height of the wall is restricted to the edge of the window. Furthermore, in recent years, the speed has become extremely high, and the speed becomes 350 km / h, and the speed becomes 97 m / sec. Therefore, the energy of the generated vibration noise is unimaginable. The sound-absorbing wall of the present invention is a sound-absorbing wall utilizing an extremely high level of technology capable of coping with various soundproofing effects.

[0009] The noise and wind pressure generated by the running of the train are changed by a rib-shaped sound absorbing plate provided on the wall surface. It is desirable that the rib-shaped sound absorbing plate 4 be erected at an angle of about 30 ° in the traveling direction as described above. This is because the flow of air on the surface of the rib-shaped sound absorbing plate becomes faster, and a vortex is generated on the back surface of the tip of the rib. The sound projected by the vortex is scattered and a part of the noise is attenuated. Further, the soundproof wall is provided with a number of rib-shaped sound absorbing plates to increase the sound absorbing area to enhance the sound absorbing effect. Next, the silencing effect will be described. The sound waves projected on the sound deadening wall enter through the sound absorbing holes of the upper sound absorbing plate 3t and enter the respective chambers defined by the partition plate 2t. This incident sound will be described in detail with reference to FIG. This diagram is a diagram that quotes Heigens' law, which is generally widely known as the principle of diffraction waves. Explained by this schematic diagram

The sound S entering the sound absorbing hole h formed in the sound absorbing plate 2A is projected as shown by the arrow and enters the sound absorbing hole. At this time, the sound absorbing hole vibrates and expands and contracts under the sound pressure. This movement causes the air on the surface of the hole to vibrate. That is, the sound pressure energy is converted into the vibration energy of air and consumed by heat radiation. This is the principle of sound absorption. The sound wave reduced by the sound absorbing hole becomes a spherical wave at the exit of the hole h, diffracts, and propagates as a diffracted wave d. The diffraction angle of this diffraction wave is 2A, 2
As compared with B, the smaller the hole diameter, the deeper the hole, and the larger the hole diameter, the shallower the light propagates. As described above, when the projection sound is divided by the upper partition wall 2t from the sound absorbing hole of the upper sound absorbing plate 3t and enters each formed chamber, the incident sound is surrounded by an arrow around the hole as shown in 2A of FIG. A part becomes a diffraction wave as shown in FIG. The anti-vibration sound-proof paint applied to the inner surface of the chamber suppresses the reflected sound in the chamber and reduces the sound. The projected sound further enters each chamber formed by the next lower sound absorbing plate 3b and the lower partition 2b from the sound absorbing hole of the sound absorbing plate 3b as a diffracted wave as described above, and the energy of the reflected resonance sound is: In the same manner as described above, the sound wave attenuated by the vibration-proof and sound-insulating paint applied to the inner surface has a phase difference with the next incoming sound wave. The sound wave disappears or attenuates due to the interference between the two phases. These actions occur continuously. The above is the outline of the muffling effect.
Next, the diffraction wave sound generated at the upper end of the standing sound deadening wall will be described. Generally, the sound wave projected on the upper part of the soundproof wall has a sound propagating linearly and a sound that bends at the top of the wall and enters the back side, that is, a diffracted wave sound, and if this diffracted sound is not prevented, the soundproofing effect of the soundproof wall is obtained. There is no. In order to prevent this, a curved surface is formed by giving a required curved surface inside the upper part of the soundproof wall. As described in Japanese Patent Application No. 49-29496, wind pressure is generated when a vehicle travels inside a soundproof wall having an upper portion curved inside on both sides of a track or a road. The generated wind pressure blows up air to generate an updraft. Naturally, the speed of the rising airflow is proportional to the speed of the vehicle. However, the speed of the rising airflow is slow at a position apart from the wall surface, and the speed of the airflow rising along the wall surface and the curved surface is the fastest (fluid flow). Therefore, it is inevitable that a vortex is generated behind the upper end of the curved surface of the sound insulating wall. Therefore, the diffraction wave sound projected into the vortex is scattered and disappears.
As shown in FIGS. 10, 11, 12, and 13, when only the upper sound absorbing plate 9 of the sound deadening wall is formed by a single plate, the rib-shaped sound absorbing plate to be erected can be easily erected, thereby reducing the processing cost. Can be cheap. Further, it is possible to provide a soundproof wall having an effect that sound can be easily taken into the wall body.

According to a fourth aspect of the present invention, when only the curved surface portion of the upper sound absorbing plate 3t is separated and separately processed and mounted, the construction can be simplified. This is as shown in FIGS.
Also, it is extremely difficult to form a rib-shaped sound-absorbing plate on a curved portion. In such a case, if a molding process is made of a transparent plastic material, a sound-insulating wall which is easy to form and has a transparent property can be obtained. The effect that can be achieved is extremely large.

[0012]

As described above, the sound deadening wall of the present invention forms a phase difference between sound waves and sound waves, that is, a projected sound and a reflected sound, and interferes with both of the sound waves and the sound waves to muffle the sound. The sound absorbing effect is increased by increasing the sound absorbing area by the sound absorbing effect and the rib-shaped sound absorbing plate erected on the upper surface of the wall.
In addition, by inclining the rib-shaped sound absorbing plate in the traveling direction, a vortex is generated, and the projected sound is scattered and reduced. Further, the sound deadening wall has a double-layered soundproofing effect, such as forming a curved surface or a curved rib sound absorbing plate on the upper wall surface to prevent diffraction wave noise. Next, the interference effect due to the phase difference between the projected sound and the reflected sound will be described. As shown in FIG. 20A, a sound-absorbing wall sample is installed, and a projection sound is projected from the speaker to the sound-absorbing wall sample at an angle of 45 °. As a result of comparing the frequencies of the reflected sounds, the fourth
A waveform having a phase difference as shown in FIG. B is obtained. Then, when these two waveforms are combined, the peaks and valleys of the waveform overlap and interfere with each other as shown in FIG. 4C. Disappears or is attenuated. When the sound-absorbing plate is formed of a single material such as a metal plate, plastic, or an inorganic material as described in claim 6, the sound-absorbing effect is slightly inferior, but processing can be extremely easily performed. As described above, when the sound deadening wall according to the present invention is installed on a Shinkansen track or a high-speed vehicle and soundproofed, various soundproofing effects such as the following are provided. A plurality of sound absorbing plates are provided upright to increase the sound absorbing area, and by inclining the rib-shaped sound absorbing plates in the traveling direction, a vortex is generated on the back of the plate, and sound waves are scattered by the vortex to reduce sound. A curved surface is provided at the top of the standing sound-absorbing wall, and by changing the flow of the airflow, a vortex is generated at the back of the tip of the curve to prevent the diffracted wave sound diffracting at the top of the wall from being scattered by the vortex. It is a sound-absorbing wall that has an extremely excellent sound-proofing effect, with the combined sound-proofing effects such as effects.

[Brief description of the drawings]

FIG. 1 is a front view showing an example of a sound deadening wall according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a longitudinal sectional view of FIG.

FIG. 4 is a view showing in detail a part of a sound absorbing hole formed in the sound absorbing plate of FIG. 3; FIGS. 5, 6, 7, 8 and 9 are views showing the assembly of an example of the sound deadening wall of the present invention.

FIG. 5 is an upper sound absorbing plate in which a plurality of rib-shaped sound absorbing plates are erected on a surface and a curved surface is provided on an upper portion.

FIG. 6 is an upper partition plate.

FIG. 7 is a lower sound absorbing plate.

FIG. 8 is a view in which a partition plate is attached to a lower portion of the inside of a wall, and a vibration-proof and sound-proof paint is applied.

FIG. 9 is a reinforcing plate for fixing the back of the curved plate.

FIG. 10 is a front view of another sound deadening wall (claim 3).

11 is a longitudinal sectional view of FIG.

FIG. 12 is a diagram showing a part of FIG. 11 in detail.

FIG. 13 is a view showing a cross section AA of FIG. 10;

FIG. 14 is a diagram in which a rib-shaped sound absorbing plate is erected on a curved portion.

FIG. 15 is a side view of FIG. 14;

FIG. 16 is a front view of an example of the sound-absorbing wall of the present invention, in which a rib-shaped sound-absorbing plate erected on a surface portion is vertically installed on the surface.

FIG. 17 is a perspective view of FIG. 16;

FIG. 18 is a sectional view taken along line AA of FIG.

FIG. 19 is a diagram macroscopically showing a relationship between a projection sound, a sound absorbing hole, and a diffraction wave.

FIG. 20 is a diagram illustrating a device A for measuring the phase difference between the projected and reflected sounds of the sound deadening wall of the present invention, and the principle of the interference effect due to the phase difference.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wall 2t, 2b Partition plate 3t, 3b Sound absorbing plate 4, 4p Rib-shaped sound absorbing plate 5, 5 'Bending part 6 Protective plate 7 Bracket 8 Receiving stand 9, 9' Single sound absorbing plate S Projection sound h Sound absorption hole d times Analyzed sound 2A, 2B Sound absorbing plate 2C Sound insulation wall A Measuring device B Interference device by phase difference

Claims (6)

[Claims] 1. A lower portion of a box-shaped wall 1 made of a hard material such as a metal plate, plastic, a wooden plate, or an inorganic material is partitioned and fixed by a partition plate 2b. A vibration-proof and sound-proof paint formed by mixing and uniformly dispersing metal powder or heavy-mass powder is applied to the entire inner surface of the partitioned compartment. A laminated board in which a soundproofing material, that is, a sound absorbing material in which an inorganic or organic fiber such as asbestos, glass fiber, rock wool or the like is formed in a panel shape is interposed between the panels, on the partition plate 2b in the wall body having the above structure. Sound absorbing plate 3b formed by drilling a plurality of holes
And a partition plate 2t is mounted thereon. The anti-vibration and sound-proof paint is also applied to the mounted sound absorbing plate 3b, the partition plate 2t, and the upper part in the wall body 1. To the top of the above structure,
A sound absorbing plate 3t having a structure in which a curved surface 5 is further provided at one longitudinal end of the sound absorbing plate 3t having a plurality of rib-shaped sound absorbing plates 4 mounted on the upper surface of the sound absorbing plate 3t is mounted. A sound-absorbing wall characterized by that. 2. The rib-shaped sound absorbing plate 4 according to claim 1.
At a required angle with respect to the surface of the sound absorbing plate 3t,
A sound-absorbing wall characterized by being mounted at an angle. 3. The sound deadening wall according to claim 2, wherein
The upper sound absorbing plate 9 is provided with a rib-shaped sound absorbing plate P on a single plate, that is, a sound absorbing plate 9 formed by drilling a plurality of through holes in a metal plate, and the rib-shaped sound absorbing plate end and the curved plate 9 ' A sound-absorbing wall characterized in that the sound-absorbing wall is connected and fixed by a bracket 7 and is formed by attaching a protective cover 6 to a back portion. 4. A sound deadening wall, wherein the curved portion 5 of the upper sound absorbing plate 3t according to claim 1 is processed separately from the sound absorbing plate 3t and is attached thereto. 5. A sound-absorbing wall, wherein a plurality of rib-shaped sound-absorbing plates 4 are vertically mounted and fixed on the surface of the upper sound-absorbing plate 3t according to claim 1. 6. A sound-absorbing wall, wherein the sound-absorbing plate according to claim 1 is formed of a single material such as a metal plate, plastic, or an inorganic material.