CN111719450A

CN111719450A - Near-orbit sound barrier

Info

Publication number: CN111719450A
Application number: CN202010598140.9A
Authority: CN
Inventors: 吴生提; 李林; 李登科; 黄志华; 张晶福; 王达
Original assignee: Zhuzhou Guochuang Track Technology Co ltd
Current assignee: Zhuzhou Guochuang Track Technology Co ltd
Priority date: 2020-06-28
Filing date: 2020-06-28
Publication date: 2020-09-29

Abstract

The invention provides a near-rail sound barrier, which comprises a base and a plurality of first acoustic modules, wherein the first acoustic modules are arranged on the base; the first acoustic module comprises a first perforated plate and a sound absorption structure which are connected in a stacked mode, a plurality of resonant cavities with different depths are arranged in the sound absorption structure, and each resonant cavity faces the first perforated plate. The invention utilizes the Helmholtz resonance sound absorption principle and adopts the combination of a plurality of resonant cavities with different depths, thereby effectively realizing the broadband sound absorption of medium and low frequency, and particularly adopting a symmetrical L-shaped resonant cavity structure, obviously reducing the space requirement of the structure and leading the structure to be more compact. Meanwhile, according to the performance requirements of different scenes, the diameter of the first through plate hole and the depth of the resonant cavity can be flexibly designed and adjusted, and the first through plate hole can be matched with a traditional sound absorption material for use, so that the sound absorption requirements of high, medium and low frequencies can be met simultaneously, and the optimal application effect is achieved.

Description

Near-orbit sound barrier

Technical Field

The invention belongs to the technical field of road noise reduction facilities, and particularly relates to a near-orbit sound barrier.

Background

With the rapid development of high-speed railways in China, the speed of trains is continuously improved, the following railway noise is more and more obvious, the noise pollution to the surrounding environment of the railways is continuously intensified, and the sound barrier is the trackside noise reduction equipment which is widely applied. The existing sound barrier is mainly made of materials such as concrete and aluminum alloy, the sound absorption performance of medium and low frequencies is insufficient, the noise reduction effect is concentrated on medium and high frequencies above 1000Hz, and the low-frequency part of wheel track noise below 1000Hz occupies a large proportion. Meanwhile, the existing sound barrier does not consider the frequency spectrum characteristics of the rail noise, for example, the noise reduction requirements of subways and motor cars are different due to different speed intervals, and the existing sound barrier is not designed for the frequency characteristics of the rail noise, so that the application effect under different scenes is poor.

Therefore, there is a need for a sound barrier for near-rail sound that can meet the requirements of low-frequency sound absorption in the periphery of the rail and has better application effect.

Disclosure of Invention

The invention aims to provide a near-rail sound barrier, and aims to solve the technical problems that in the prior art, the low-medium frequency sound absorption performance is insufficient, the frequency characteristic of rail noise is not designed, and the application effect is poor.

The invention provides a near-rail sound barrier, which comprises a base and a plurality of first acoustic modules, wherein the first acoustic modules are arranged on the base; the first acoustic module comprises a first perforated plate and a sound absorption structure which are connected in a stacked mode, a plurality of resonant cavities with different depths are arranged in the sound absorption structure, and each resonant cavity faces the first perforated plate.

Further, the sound absorption structure comprises a base shell and a plurality of partition plates; the base shell is of a closed structure, and the partition plates are arranged in the base shell and are divided into a plurality of resonant cavities with different depths;

each resonant cavity forms a plurality of resonant cavity groups, each resonant cavity group comprises a plurality of resonant cavities with gradually increasing depths, and in the direction towards the first perforated plate, any one resonant cavity is surrounded by the adjacent resonant cavities with large depths.

Further, the partition plate comprises a separation groove body, a first vertical plate and a second vertical plate; at least one first vertical plate is arranged in the basic shell to form a plurality of cavities, any cavity comprises a plurality of resonant cavity groups arranged side by side, the spacing groove bodies are arranged in the cavities in a step-by-step interval stacking mode, and a second vertical plate is arranged in the middle of each cavity to form resonant cavities with different depths.

Furthermore, each cavity structure is symmetrical, and any cavity comprises two symmetrically arranged resonant cavity groups, and the gaps formed by stacking the spaced groove bodies step by step are equal.

Further, the first acoustic module further comprises a second perforated panel and a sound absorbing material; the second perforated plate, the sound absorption material, the first perforated plate and the sound absorption structure are sequentially connected in a stacked mode; the second perforated plate has a hole diameter larger than a hole diameter of the first perforated plate.

Further, a plurality of the first acoustic modules are mounted on the base in a longitudinally stacked arrangement.

The sound-absorbing structure further comprises a second acoustic module, wherein the second acoustic module comprises a second perforated plate, a sound-absorbing material and a frame structure which are sequentially connected in a stacked mode; the hole diameter of the second perforated plate is larger than that of the first perforated plate; the frame structure is connected with the base, and the first acoustic module and the second acoustic module are longitudinally stacked and arranged on the base.

Further, the first acoustic module and the second acoustic module are sequentially arranged in a staggered manner.

Further, the sound absorption material is at least one of rock wool, glass wool or PU, and when the sound absorption material is two or more, an acoustic membrane is arranged between the sound absorption materials.

Further, the diameter of the second perforated plate hole is larger than or equal to a limit value, and the diameter of the first perforated plate hole is smaller than the limit value, wherein the limit value is 1.5-2.5 mm.

The near-orbit sound barrier provided by the invention has the beneficial effects that: the near-orbit sound barrier comprises a base serving as a supporting structure and a plurality of first acoustic modules mounted on the base, wherein each first acoustic module comprises a first penetrating plate and a sound absorption structure, the sound absorption effect is mainly achieved, and the sound absorption structure is composed of a plurality of resonant cavities with different depths. The low-frequency sound absorption uses the Helmholtz resonance sound absorption principle, and a single resonant cavity only can generate a resonance sound absorption peak value and has a narrow frequency band, so that the combination of a plurality of resonant cavities with different depths is adopted, and the broadband sound absorption of medium and low frequencies is effectively realized. Meanwhile, according to the performance requirements of different scenes, the diameter of the first through plate hole and the depth of the resonant cavity can be flexibly designed and adjusted, and the best application effect is achieved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a near-rail sound barrier in the present embodiment;

FIG. 2 is a side view of the near-rail sound barrier of the present embodiment;

FIG. 3 is a schematic structural view of the sound absorbing structure in this embodiment;

fig. 4 is a schematic structural diagram of a first acoustic module according to the present embodiment;

FIG. 5 is a functional graph illustrating sound absorption performance of a first acoustic module according to the present embodiment;

fig. 6 is an arrangement front view of a near-orbital sound barrier in this embodiment;

fig. 7 is a schematic structural diagram of another first acoustic module and a second acoustic module in the present embodiment;

fig. 8 is an arrangement elevation view of another near-orbital sound barrier in this embodiment;

fig. 9 is a schematic structural view of the sound absorbing material in this embodiment.

The designations in the figures mean:

1. a base; 2. a first acoustic module; 3. a second acoustic module; 21. a first perforated plate; 22. a sound absorbing structure; 221. a base housing; 222. a separation groove body; 223. a first vertical plate; 224. a chamber; 225. a second vertical plate; 31. a second perforated plate; 32. a sound absorbing material; 321. an acoustic membrane; 33. the frame structure.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

It is to be understood that the terms "upper", "lower", "left", "right", and the like, as used herein, refer to an orientation or positional relationship based on that shown in the drawings, which is for convenience of description only, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be considered limiting of this patent. The terms "first", "second" and "first" are used merely for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "plurality" is two or more unless specifically limited otherwise. Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

It should also be noted that, unless expressly stated or limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may for example be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In order to explain the technical solution of the present invention, the following detailed description is made with reference to the specific drawings and examples.

Referring to fig. 1, the present embodiment provides a near-rail sound barrier, which includes a base 1 and a plurality of first acoustic modules 2 mounted on the base 1; the first acoustic module 2 includes a first perforated plate 21 and a sound absorbing structure 22 which are connected in a stacked manner, a plurality of resonant cavities with different depths are provided in the sound absorbing structure 22, and each resonant cavity is provided toward the first perforated plate 21.

As shown in fig. 1 and fig. 2, the near-rail sound barrier provided by this embodiment includes a base 1, the base 1 is installed beside a track as a supporting structure, and a plurality of first acoustic modules 2 are installed on the base 1 to absorb sound. Wherein the first acoustic module 2 comprises a first perforated plate 21 and a sound absorbing structure 22 consisting of a plurality of resonant cavities of different depths, which are connected in a stack. Different from the structure that the sound barrier in the prior art adopts materials such as concrete, aluminum alloy, the sound absorption structure 22 of this nearly rail sound barrier has contained the resonant cavity of a plurality of different depths, combines first perforated plate 21, utilizes helmholtz resonance sound absorption principle can effectively absorb the wheel rail noise of low frequency in the middle of the prior art, solves the problem that low frequency sound absorption performance is not enough in the prior art.

According to the helmholtz resonance sound absorption principle, a single resonant cavity can only generate one resonance sound absorption peak value, the frequency band of the resonance sound absorption peak value is narrow, the sound absorption structure 22 of the near-orbit sound barrier provided by the embodiment is composed of a plurality of resonant cavities with different depths, and the resonant cavities with different depths are combined through design, so that the broadband sound absorption of medium and low frequencies is realized. Because the sound absorption performance of the medium-low frequency is mainly determined by the hole diameter of the first perforated plate 21 and the depth of the resonant cavity, different design combinations can be made on the first perforated plate 21 and the sound absorption structure 22 of the first acoustic module 2 according to the sound absorption requirements of different applicable places so as to meet various sound absorption requirements and ensure that the application effect of the near-orbit sound barrier is better. While the first acoustic module 2 structure can also be used for its semi-closed and closed sound barrier.

The beneficial effect of the near-orbit sound barrier that this embodiment provided lies in: the near-orbit sound barrier comprises a base 1 serving as a supporting structure and a plurality of first acoustic modules 2 mounted on the base 1, wherein each first acoustic module 2 comprises a first penetrating plate and a sound absorption structure 22 and mainly plays a sound absorption role, and the sound absorption structure 22 consists of a plurality of resonant cavities with different depths. The low-frequency sound absorption uses the Helmholtz resonance sound absorption principle, and a single resonant cavity only can generate a resonance sound absorption peak value and has a narrow frequency band, so that the combination of a plurality of resonant cavities with different depths is adopted, and the broadband sound absorption of medium and low frequencies is effectively realized. Meanwhile, according to the performance requirements of different scenes, the diameter of the first through plate hole and the depth of the resonant cavity can be flexibly designed and adjusted, and the best application effect is achieved.

As a further preference of the present embodiment, the sound absorbing structure 22 includes a base shell 221 and a plurality of partitions; the basic shell 221 is a closed structure, and the partition plates are arranged in the basic shell 221 and are divided into a plurality of resonant cavities with different depths;

each resonant cavity forms a plurality of resonant cavity groups, each resonant cavity group comprises a plurality of resonant cavities with gradually increasing depths, and in the direction towards the first perforated plate 21, any resonant cavity is surrounded by adjacent resonant cavities with large depths.

As shown in fig. 1, 2 and 3, the sound absorption structure provided by this embodiment includes a base casing 221 having a closed structure and a plurality of partition boards, which are vertically and horizontally combined in the base casing 221 to partition the base casing 221 into a plurality of resonant cavities with different depths. A plurality of resonant cavities of increasing depth form resonant cavity groups, each resonant cavity group being surrounded by adjacent resonant cavities of greater depth in the direction towards the first perforated plate 21. The base housing 221 may have a plurality of resonant cavity groups therein. The sound absorption structure provided by the embodiment is simple and compact in structure and more flexible in combination, and different resonant cavity groups are formed by changing the number and positions of the partition plates so as to meet different sound absorption requirements.

As a further preference of this embodiment, the partition plate includes a partition groove body 222, a first riser 223 and a second riser 225; at least one first vertical plate 223 is arranged in the base shell 221 to form a plurality of cavities 224, each cavity 224 comprises a plurality of resonant cavity groups arranged side by side, the partition groove bodies 222 are arranged in each cavity 224 in a step-by-step interval stacking mode, and a second vertical plate 225 is arranged in the middle of each cavity 224 to form a plurality of resonant cavities with different depths.

As shown in fig. 3, the sound absorbing structure 22 includes a base casing 221 of a closed structure, a first riser 223 is disposed in the base casing 221 to form a plurality of chambers 224, in this embodiment, the number of the first risers 223 is one, the base casing 221 is divided into two chambers 224, the number of the first risers 223 can be set according to actual requirements, and the base casing 221 is divided into three, four or more chambers 224. A plurality of spacing groove bodies 222 are stacked in each cavity 224 in a step-by-step interval manner, in this embodiment, the number of the spacing groove bodies 222 in each cavity 224 is also one, and a second vertical plate 225 is arranged in the middle of each cavity 224, so that the spacing groove bodies 222 in each cavity 224 are divided into a plurality of resonant cavities with different depths.

As shown in fig. 3, the base shell 221 and the partition groove 222 are square, the second vertical plate 225 divides each chamber 224 into left and right sides, and the partition groove 222 in each side is divided into an L-shape. The spacing grooves 222 and the second vertical plate 225, and the first vertical plate 223, the second vertical plate 225 and the base shell 221 can be connected by welding or bonding, so that resonant cavity structures with different depths can be obtained. The structure does not change the resonance characteristic of Helmholtz, the combination of the step-by-step gap stacking of the spacing groove body 222 is flexible and compact, a thin sound absorption module can be formed, and the resonance sound absorption structure has the advantages of small thickness, wide noise reduction frequency and the like.

The grade of the sound absorbing structure 22 is determined by the number of the spaced grooves 222, and the sum of the number of the spaced grooves 222 and the number of the basic casing 221 disposed in each chamber 224 is the grade of the sound absorbing structure 22, as shown in fig. 3, this embodiment provides a two-stage sound absorbing structure 22. The higher grade sound absorbing structure 22 will have a greater sound absorbing bandwidth as the peak sound absorption increases, so a higher grade will perform better, but at a higher cost and with more difficulty in manufacture. The grade of sound absorbing structure 22 may be selected as appropriate for the application.

As a further preferred embodiment of the present invention, each chamber 224 has a symmetrical structure, and each chamber 224 includes two symmetrically disposed resonant cavity groups, and the gaps between the spaced grooves 222 stacked in a stepwise manner are equal.

As shown in fig. 3, the first vertical plate 223 divides the base shell 221 into uniform chambers 224, and the partition grooves 222 are uniformly arranged in each chamber 224 step by step, so that the position of the second vertical plate 225 is also exactly in the middle of the partition grooves 222, and each chamber 224 is symmetrical in structure, and two adjacent chambers 224 are symmetrical in structure. The even symmetrical structure makes the position of any part of first acoustic module 2 middle low frequency resonance inhale balanced orderly, and its sound absorbing effect is better, and the symmetrical structure makes sound absorbing structure 22's structure under the equivalent effect compacter simultaneously, has effectively saved installation space.

As shown in fig. 3, the gaps formed by stacking the spaced grooves 222 in stages are equal, so that the structure of the whole sound absorbing structure 22 is more symmetrical and ordered. The gaps between the spaced slots 222 in each chamber 224 are equal, so that the widths of the resonant cavities are consistent and the depths of the resonant cavities are different. Furthermore, the sound absorption effect is better, the structure is more compact, and the installation space is effectively saved.

As a further preference of the present embodiment, the first acoustic module 2 further includes a second perforated plate 31 and a sound absorbing material 32; the second perforated plate 31, the sound-absorbing material 32, the first perforated plate 21 and the sound-absorbing structure 22 are sequentially connected in a stacked manner; the hole diameter of the second perforated plate 31 is larger than the hole diameter of the first perforated plate 21.

As shown in fig. 4, the first acoustic module 2 is formed by sequentially stacking and connecting the second perforated plate 31, the sound absorbing material 32, the first perforated plate 21, and the sound absorbing structure 22. Wherein the high frequency depends on the sound absorbing properties of the fibrous and porous material itself, and the second perforated plate 31 and the sound absorbing material 32. The present embodiment places the second perforated plate 31 and the sound absorbing material 32 in the skin layer, wherein the second perforated plate 31 mainly plays a role of protection and fixing in addition to the sound absorbing function. The sound absorption structure 22 is placed on the bottom layer, so that the sound transmission and sound absorption characteristics are fully utilized, the medium-high frequency penetration capacity is weak, the sound absorption structure can be directly absorbed by the second perforated plate 31 and the sound absorption material 32, and the low frequency penetration capacity is strong, so that the sound absorption structure 22 can absorb sound by utilizing resonance. The sound absorption structure 22 resonance structure and the first perforation noise reduction structure realize the full-band broadband noise reduction structure by combining with the high-frequency sound absorption structure, and the low-frequency noise reduction effect is outstanding.

As shown in fig. 4, in which low frequencies are mainly absorbed by the resonance of the first perforated plate 21 and the sound absorbing structure 22, the first perforated plate 21 may be a single perforated plate having a suitable aperture or may be composed of a plurality of perforated plates having different diameters. Meanwhile, the sound absorption structure 22 can be selected from different grades of sound absorption structures 22 according to actual requirements. In this embodiment, fig. 5 is a graph of a sound absorption coefficient obtained by combining a single first perforated plate 21 and a four-stage sound absorption structure 22, in the graph, the four-stage sound absorption structure 22 corresponds to four sound absorption peaks, a frequency spectrum bandwidth of the four-stage sound absorption structure is wider than a frequency spectrum bandwidth of one sound absorption peak, and a broadband noise reduction effect of the four-stage sound absorption structure is better.

As a further preferable mode of the present embodiment, a plurality of first acoustic modules 2 are mounted on the base 1 in a longitudinally stacked arrangement.

As shown in fig. 6, a plurality of first acoustic modules 2 are longitudinally stacked and arranged on a base 1, the first acoustic modules 2 and the base 1 can be riveted or screwed, and then the near-rail sound barrier is mounted on two sides of a rail through the fixed base 1, so that noise reduction treatment is performed on noise of the rail. The second perforated plate 31 faces the sound source side, and the sound barrier formed by the plurality of first acoustic modules 2 has a full-band high-performance noise reduction effect.

As a further preferable feature of this embodiment, the acoustic module further includes a second acoustic module 3, and the second acoustic module 3 includes a second perforated plate 31, a sound absorbing material 32, and a frame structure 33, which are stacked and connected in this order; the hole diameter of the second perforated plate 31 is larger than the hole diameter of the first perforated plate 21; the frame structure 33 is connected to the base 1, and the first acoustic module 2 and the second acoustic module 3 are mounted on the base 1 in a vertically stacked arrangement.

As shown in fig. 7, the present embodiment provides a second sound barrier structure, a first acoustic module 2 and a second acoustic module 3 are longitudinally stacked and arranged on a base 1, the first acoustic module 2 mainly comprises a first perforated plate 21 and a sound absorption structure 22, and mainly aims at middle and low frequency sound absorption, and the middle and high frequency sound absorption is completed by the second acoustic module 3, and includes a second perforated plate 31, a sound absorption material 32, and a frame structure 33 which are sequentially stacked and connected. The first acoustic module 2 and the second acoustic module 3 are stacked longitudinally, and compared with the first sound barrier structure shown in fig. 6, in which the areas of the low-frequency sound absorbing structure and the medium-high frequency sound absorbing structure are relatively reduced, the overall thickness of the sound barrier can be made thinner and the cost can be made lower, although a part of the sound absorbing and insulating performance is sacrificed.

As a further preferred embodiment, the first acoustic modules 2 and the second acoustic modules 3 are sequentially arranged in a staggered manner.

As shown in fig. 8, the first acoustic module 2 and the second acoustic module 3 are sequentially installed on the base 1 in a staggered manner, so that the overall structure is thinner, and the acoustic module is suitable for occasions with higher space limitation, and the first acoustic module 2, the second acoustic module 3 and the base 1 can be connected by riveting or screws.

As a further preference of this embodiment, the sound absorbing material 32 is at least one of rock wool, glass wool, or PU, and when the sound absorbing material 32 is two or more, an acoustic membrane 321 is provided between the sound absorbing materials 32.

As shown in fig. 9, the sound absorbing material 32 may be any one of fiber materials such as rock wool and glass wool, or foam materials such as light PU. Multiple layers of sound absorbing material 32, such as: a sound absorbing material 32, an acoustic membrane 321, and another sound absorbing material 32.

As a further optimization of the embodiment, the hole diameter of the second perforated plate 31 is larger than or equal to a limit value, and the hole diameter of the first perforated plate 21 is smaller than the limit value, wherein the limit value is 1.5-2.5 mm.

The first perforated plate 21 is generally a micro-perforated plate, and in this embodiment, the diameter of the first perforated plate 21 is less than 2 mm. The second perforated plate 31 is generally a conventional perforated plate, and in this embodiment, the diameter of the second perforated plate 31 is more than 2 mm. The second perforated plate 31 absorbs high-frequency noise, the low-frequency noise reaches the first perforated plate 21 by virtue of strong penetrating power, and the sound absorption structure 22 with a plurality of resonant cavities with different depths is combined to perform resonance sound absorption on the low-frequency noise, so that the full-band high-performance noise reduction effect is ensured.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts of the present invention. It should be noted that there are no specific structures but a few objective structures due to the limited character expressions, and that those skilled in the art may make various improvements, decorations or changes without departing from the principle of the invention or may combine the above technical features in a suitable manner; such modifications, variations, combinations, or adaptations of the invention using its spirit and scope, as defined by the claims, may be directed to other uses and embodiments.

Claims

1. A near-rail sound barrier comprising a base and a plurality of first acoustic modules mounted on the base; the first acoustic module comprises a first perforated plate and a sound absorption structure which are connected in a stacked mode, a plurality of resonant cavities with different depths are arranged in the sound absorption structure, and each resonant cavity faces the first perforated plate.

2. The near rail sound barrier of claim 1 wherein said sound absorbing structure comprises a base housing and a plurality of baffles; the base shell is of a closed structure, and the partition plates are arranged in the base shell and are divided into a plurality of resonant cavities with different depths;

3. The near-rail sound barrier of claim 2, wherein the partition comprises a spacer channel, a first riser, and a second riser; at least one first vertical plate is arranged in the basic shell to form a plurality of cavities, any cavity comprises a plurality of resonant cavity groups arranged side by side, the spacing groove bodies are arranged in the cavities in a step-by-step interval stacking mode, and a second vertical plate is arranged in the middle of each cavity to form resonant cavities with different depths.

4. The near-rail sound barrier of claim 3, wherein each chamber is symmetrical in structure, and each chamber comprises two symmetrically arranged resonant cavity groups, and the gaps formed by stacking the separation grooves in a stepwise manner are equal.

5. The near rail sound barrier of claim 1, wherein said first acoustic module further comprises a second perforated panel and a sound absorbing material; the second perforated plate, the sound absorption material, the first perforated plate and the sound absorption structure are sequentially connected in a stacked mode; the second perforated plate has a hole diameter larger than a hole diameter of the first perforated plate.

6. The near-rail sound barrier of claim 5 wherein a plurality of said first acoustic modules are mounted on said base in a longitudinally stacked arrangement.

7. The near rail sound barrier of claim 4, further comprising a second acoustic module comprising a second perforated panel, sound absorbing material, and frame structure in sequential stacked connection; the hole diameter of the second perforated plate is larger than that of the first perforated plate; the frame structure is connected with the base, and the first acoustic module and the second acoustic module are longitudinally stacked and arranged on the base.

8. The near rail sound barrier of claim 7, wherein the first acoustic module is sequentially staggered from the second acoustic module.

9. The near-rail sound barrier of any one of claims 5 to 8, wherein the sound absorbing material is at least one of rock wool, glass wool, or PU, and when the sound absorbing material is two or more, an acoustic membrane is disposed between the sound absorbing materials.

10. The near-orbital sound barrier of any one of claims 5 to 8, wherein the second perforated plate has a hole diameter greater than or equal to a defined value, and the first perforated plate has a hole diameter smaller than the defined value, wherein the defined value is 1.5 to 2.5 mm.