JPH11107672A - Soundproof construction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize sufficient soundproof characteristics against low frequency sound with a construction that can be assembled easily. SOLUTION: A soundproof construction 11 is to be used for a tunnel such as a pit mouth in which an H-section steel 12 bent as a frame body by a bending process to an arch shape of a tunnel is attached to the inner peripheral surface of the tunnel to which primary lining work is applied by spraying fresh concrete, and an RC footing is built at the bottom of the tunnel and a number of round steel pipes 17 are built upright side by side without gaps between them by inserting the bottom ends of the pipes into recesses formed in the footing in advance thereby creating a soundproof pipe wall 18. Here, each round steel pipe 17 is constituted as a hollow pipe; at the top end of each pipe, a penetrated pipe 19 as communicating means through the soundproof wall 18 is connected to each round steel pipe 17 in such a manner that the hollow space in the penetrating pipe 19 is connected and communicates with each hollow space of the steel pipe 17 erected vertically, and the upper end of the each steel pipe 17 is fixed to the H-section steel frame 12 through each penetrating pipe 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soundproof structure mainly used for insulating low-frequency sound in blasting excavation work for a tunnel or the like.

[0002]

2. Description of the Related Art A blasting sound generated in a tunnel excavation work or the like has a characteristic that it is shocking, includes a wide frequency band, and has a high sound pressure level. Therefore, if the blasting sound leaks out of the tunnel pit, not only does it cause noise in the vicinity, but also low-frequency components contained in the blasting sound vibrate fittings such as shojis and windows to generate rattling noise.

[0003] Therefore, when blasting, a predetermined number of soundproof walls are installed between the pit and the face to shield the cross section of the tunnel so that the blasting sound is prevented from leaking outside the pit.
FIG. 6 shows such a soundproof wall 1 in a perspective view.
As shown in the figure, the soundproof wall 1 is installed at a position away from the face 4 and is made of H-shaped steel or the like over the tunnel cross section.
And a soundproof panel 3 is attached to the skeleton 2.

[0004]

However, such ordinary soundproofing panels 3 are often manufactured for noise reduction or improved in accordance with the weight rule, so that the soundproofing performance against blasting sound is poor. Was inferior. For example, two iron plates or perforated metal
Oppositely arranged at an interval of about 0 cm and the space between them is a hollow part,
A sound absorbing material such as glass wool is disposed at a thickness of about 5 cm in the hollow portion, and the remaining thickness is left hollow.
The rigidity is considerably reduced, and a problem has arisen that the low-frequency sound generated by the blast just resonates.

[0005] Such a problem causes a large out-of-plane bending vibration in the soundproof panel due to the low-frequency sound generated by the blasting, and the vibration causes secondary radiation of the low-frequency sound to the outside to cause damage to the surroundings.

Further, if the scattered rock at the time of blasting hits the soundproofing panel, the relatively thin sound insulating material may be damaged, so that there is also an inconvenience that blasting cannot be performed near a soundproofing wall. .

In order to avoid such a situation, the soundproof wall may be formed of concrete to improve the sound insulation performance. However, it is inevitable that difficulties occur in assembling, dismantling, removing, and diverting.

The present invention has been made in view of the above-mentioned circumstances, and has as its object to provide a soundproof structure which is easy to handle in assembling and disassembling and has sufficient sound insulation characteristics for low-frequency sounds. .

[0009]

In order to achieve the above object, the soundproof structure of the present invention comprises a plurality of steel pipes arranged adjacent to each other in parallel to form a soundproof body, as described in claim 1. And a communication means for mutually communicating two spaces separated by the soundproof body.

[0010] In the soundproof structure of the present invention, two adjacent steel pipes among the steel pipes are welded to each other.

Further, the soundproof structure of the present invention is characterized in that a predetermined number of steel pipes are welded in advance in a state of being juxtaposed to form a panel unit,
The soundproof body is constituted by connecting the panel units to each other via predetermined connecting means.

Further, in the soundproof structure of the present invention, the steel pipe is a round steel pipe.

Further, in the soundproof structure of the present invention, the communicating means may be such that the steel pipe is a hollow pipe, and the other end of the hollow pipe is connected to a through pipe passing through the soundproof body to a hollow space in the hollow pipe. It is configured by connecting in such a manner.

Further, in the soundproof structure of the present invention, the communicating means may be configured such that the steel pipe is a hollow pipe, and one end of the hollow pipe has a first opening opened in one space partitioned by the soundproof body. In addition to the above, the second end of the hollow tube is provided with a second opening which is opened in the other space partitioned by the soundproof body.

In the soundproofing structure according to the present invention, a large number of steel pipes are arranged in parallel without gaps to construct a soundproofing body.
In the longitudinal direction of the steel pipe, the rigidity is remarkably improved as compared with the conventional soundproof panel. Therefore, there is almost no concern that the soundproof body resonates with the low frequency component of the blast sound and emits secondary radiation.

Many steel pipes may be simply arranged side by side without any gap. However, if two adjacent steel pipes are welded to each other, the rigidity of the steel pipes in not only the longitudinal direction but also the connecting direction is remarkably increased. It is possible to more reliably prevent secondary radiation due to the low frequency component of the blast sound.

When the steel pipes are welded to each other, they may be welded one by one on site. However, a predetermined number of steel pipes are welded in advance in a juxtaposed state to form a panel unit. Are connected to each other via a predetermined connecting means to constitute the soundproofing body.If the soundproofing body is divided into several panel units, it becomes possible to handle the soundproofing body. Since the on-site welding operation is avoided, the assembling and disassembly can be performed efficiently.

The steel pipe may be round or square, but if the steel pipe is a round steel pipe, the impact of the rock scattered at the time of blasting can be reduced on the peripheral surface of the round steel pipe. Damage to the steel pipe can be prevented beforehand.

The communication means may be provided at any place as long as it can release the blast pressure at the time of blasting and prevent the damage of the soundproofing body beforehand. An opening may be provided in the frame for fixing as a communicating means, or an opening may be provided in a predetermined portion of the soundproofing body to serve as a communicating means. If a through pipe penetrating the soundproofing body is connected to the other end of the pipe so as to be communicated with the hollow space in the hollow pipe, the steel pipe and the penetrating pipe not only allow the blast pressure to escape but also Also, it acts as a side branch type silencer, and can greatly reduce the sound pressure of loud blast noise generated when the blast escapes.

[0020] The communicating means may be a steel pipe having a hollow pipe, one end of the hollow pipe having a first opening which is open in one space partitioned by the soundproof body, and If the other end of the pipe is provided with a second opening which is opened in the other space partitioned by the soundproofing body, such a steel pipe can not only release the blast pressure but also serve as an orifice type silencer. And the sound pressure of the loud blast sound generated when the blast escapes can be greatly reduced.

[0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a soundproof structure according to an embodiment of the present invention. It is to be noted that the same reference numerals are given to components and the like that are substantially the same as those in the conventional technology, and description thereof will be omitted.

1 and 2 are a front view and a sectional view of the soundproof structure according to the present embodiment. As can be seen from these figures, the soundproofing structure 11 of the present embodiment is based on the premise that the soundproofing structure 11 is installed in a tunnel, for example, a wellhead of the tunnel. An H-shaped steel 12 as a frame bent along the arch shape of the tunnel is attached, and a large number of round steel pipes are inserted into steel pipe building recesses 16 previously embedded in an RC foundation 13 installed on the tunnel bottom 15. A soundproof wall 18 as a soundproof body in which a round steel pipe 17 is erected in a columnar shape is formed by fitting the lower ends of the pipes 17 adjacent to each other without any gap.

Here, the round steel pipe 17 is formed as a hollow pipe as can be clearly seen from FIG. 2 (a), and a penetrating pipe 19 as a communicating means penetrating the soundproof wall 18 is provided at the upper end thereof.
Are connected so as to communicate with the hollow interior of the round steel pipe 17, and the upper end of the round steel pipe 17 is fixed to the H-shaped steel 12 as a frame through the through pipe 19. Round steel pipe 17
Is preferably set to, for example, about 200 to 250 mm.

The soundproof wall 18 is provided with a ventilator 20, a worker's door 21 and a vehicle door 22 so as to be openable and closable. I can do it.

The worker's door 21 and the vehicle's door 22 have a difference between a single opening and a double opening, but basically, the point that the round steel pipe 17 described above is fitted into the door frame without any gap is almost the same. Therefore, here, only the vehicle door 22 will be described.

The vehicle door 22 is a so-called double-door type door, and is constituted by a pair of door panels 23 as shown in FIG. As can be seen from FIG. 2 (b), the door panel 23
A round steel pipe 17 having a penetrating pipe 19 connected to the upper end thereof is fitted into a square door frame 31 without any gap, and is fixed at several points on the way with a holding plate 32. In addition, above the vehicle door 22, a steel pipe building frame 33 is hung horizontally, and the lower end of the round steel pipe 17 to which the through pipe 19 is connected at the upper end is fitted into the frame.

As shown in FIG. 4 (a), the round steel pipes 17 of the door panel 23 are joined to each other by welding 41 to secure rigidity in a connecting direction. In addition,
The portions other than the door panel 23 can be welded on site as described later.

In order to construct the soundproof structure according to the present embodiment, an H-shaped steel 12 bent along the arch shape of the tunnel is attached to the inner peripheral surface 14 of the tunnel which has been primarily covered with shotcrete. , Tunnel bottom 1
The steel pipe building recess 16 is buried in the RC foundation 13 installed in 5 in advance.

Next, the round steel pipe 17 is inserted into the steel pipe building recess 16.
Are fitted without any gaps with their lower ends adjacent to each other, and their upper ends are fixed to the H-section steel 12 through the through pipes 19.

Next, the round steel pipes 17 are welded to each other, and the vehicle door 22, the worker door 21, and the ventilation port 2 are welded.
0 is provided to complete the soundproof wall 18. In addition, door panel 2
As for 3, it is preferable to carry out welding and assembly at a factory in advance and then carry it into the site.

In the soundproofing structure of the present embodiment, since a number of round steel pipes 17 are erected and joined together by welding to form a soundproof wall, the rigidity in both the longitudinal direction and the connecting direction is remarkably high. Even if the blast sound generated inside the tunnel arrives, the sound barrier does not resonate with the low-frequency sound included in the blast sound. There is almost no risk of radiation.

Further, since the blast due to the blast escapes to the outside of the mine through the through pipe 19, there is no possibility that the blast pressure acts directly on the soundproof wall 18 to cause breakage. Since the round steel pipe 17 connected to the penetrating pipe functions as a resonance type silencer together with the penetrating pipe 19, the sound generated at the moment when the blast escapes is greatly reduced.

That is, when the blast passes through the penetration tube 19,
A sound wave having a wavelength corresponding to the length of the round steel pipe 17 resonates in the steel pipe. Then, the energy of the air vibration resonating in the round steel pipe 17 is rapidly attenuated instead of the thermal energy due to friction when entering and exiting the penetration pipe 19.

Therefore, the length of the hollow space in the round steel pipe 17 is one-fourth of the low-frequency sound included in the blast sound.
If the length is adjusted to about the wavelength and the length of the round steel pipe 17 itself is too long, a partition may be provided in the steel pipe or padding may be performed in accordance with the target wavelength.

As described above, according to the soundproofing structure of the present embodiment, the soundproof wall 18 is constructed by arranging a number of round steel pipes 17 in parallel without any gap, so that the conventional soundproofing is performed in the longitudinal direction of the steel pipes. Rigidity is significantly improved compared to panels.
Therefore, there is almost no concern that the entire soundproof wall resonates with the low frequency component of the blast sound and emits secondary radiation.

Further, according to the present embodiment, the two round steel pipes 17 adjacent to each other are welded to each other, so that the rigidity of the round steel pipes 17 is markedly increased not only in the longitudinal direction but also in the connecting direction. It is possible to more reliably prevent secondary radiation due to the low frequency component of the blast sound.

Further, according to the present embodiment, since the round steel pipe 17 is employed as the steel pipe, the impact of the rock scattered at the time of blasting can be mitigated on the peripheral surface, and the damage of the steel pipe can be prevented beforehand. Can be prevented.

As a result of reducing the secondary radiation at the soundproof wall 18 and preventing damage to the soundproof wall 18, if even a large rock collision is avoided, a position quite close to the soundproof wall 18, for example, about 10 m. This makes it possible to excavate by blasting, and it is possible to prevent a situation in which inefficient mechanical excavation must be performed until the vehicle goes away from the soundproof wall by 50 to 100 m or more as in the related art.

According to the present embodiment, the round steel pipe 17
Is a hollow pipe, and the other end of the hollow pipe is connected to a through pipe 19 penetrating the soundproof wall 18 so as to communicate with a hollow space in the hollow pipe.
Not only simply releases the blast pressure, but also acts as a side branch silencer, greatly reducing the sound pressure of the blast noise generated when the blast escapes.

Since the soundproof wall made of a round steel pipe joined by welding has a sufficient sealing property and cotton density,
A sufficient sound insulation effect can be expected for ordinary noise.

In this embodiment, an example in which the present invention is applied to a blasting operation in a tunnel, that is, excavation in a horizontal direction has been described. However, the present invention is applicable to, for example, forming a vertical ventilation port in a mountain tunnel or starting a shield machine. Can also be applied to blasting work in shafts to perform blasting. In the case of such a configuration, the soundproof body of the present invention becomes a soundproof floor.

In this embodiment, two adjacent round steel pipes 17 are welded to each other. However, if sufficient rigidity can be ensured, such welding is omitted, and the pipes are simply arranged without gaps. May be.

Further, in this embodiment, the round steel pipes 17 constituting the soundproof wall 18 are arranged vertically, but they may be arranged horizontally, or a square may be used instead of the round. Needless to say.

Further, in the present embodiment, the round steel pipe 17 is carried into the site alone and is erected at a predetermined tunnel sectional position, and then the welding operation is performed on site. Thus, the panel unit 42 as shown in FIG. 4B may be manufactured in a factory in advance and assembled on site.

That is, the panel unit 42 shown in FIG.
For example, four round steel pipes 17 are connected to each other by welding 41, and a connecting flat steel 43 as a connecting means welded to the round steel pipes at both ends is connected to an adjacent panel unit 42. The adjacent panel units 42, 42 can be joined to each other by abutting the connecting flat steel 43 formed in the same manner, and in this state, by passing the bolt 44 through and fastening with the nut 45.

According to this configuration, it is possible to handle the soundproof wall 18 in a state of being divided into several panel units, which facilitates transportation and avoids welding work on site, so that assembly and disassembly can be performed. It can be performed efficiently.

Further, in this embodiment, the side branch type silencer is employed as the communication means, but an orifice type silencer as shown in FIG. 5 may be employed in place of such a configuration.

In the communicating means shown in FIG. 5, two L-shaped hollow members 51, 51 are attached to both ends of a hollow round steel pipe 17 in opposite directions, and the lower L-shaped hollow member 51 is a soundproof wall. 1
8 is a sound absorbing opening 52 as a first opening released into the inside space of the pit, which is one space partitioned by 8, and the upper L-shaped hollow member 51 is a pit which is the other space partitioned by the soundproof wall 18. Discharge port 5 as a second opening released to the outer space
It becomes 3.

According to such a configuration, the round steel pipe 17 not only releases the blast pressure but also acts as an orifice type silencer. The sound pressure of the blast sound is reduced. The degree of sound pressure reduction of the blast sound depends on the ratio between the length of the round steel pipe 17 and the diameter thereof, and may be appropriately determined in consideration of the scale of the blast, the sound pressure of the low-frequency sound, and the like.

If it is not necessary to reduce the audible sound caused by the blasting, it is not necessary to provide a muffler such as a branch type muffler or an orifice type muffler. May be provided. Such a communication opening is, for example, a ventilation port 2
The object can be achieved with a communication opening formed in the H-shaped steel 12 which is a frame body.

[0051]

As described above, according to the soundproofing structure of the present invention according to the first aspect, the rigidity of the steel pipe in the longitudinal direction is significantly improved as compared with the conventional soundproofing panel. for that reason,
There is almost no concern that the soundproofing body resonates with the low-frequency components of the blasting sound and emits secondary radiation.

According to the soundproofing structure of the present invention, the rigidity of not only the longitudinal direction but also the connecting direction of the steel pipe is remarkably improved, and the secondary radiation due to the low frequency component of the blasting sound is reduced. There is also an effect that the prevention can be performed more reliably.

Further, according to the soundproof structure of the present invention, it is possible to handle the soundproof body in a state where the soundproof body is divided into several panel units. Is avoided, so that the assembling and disassembly can be performed efficiently.

Further, according to the soundproofing structure of the present invention, the impact of the rock scattered at the time of blasting can be mitigated on the peripheral surface of the circular steel pipe, thereby preventing damage to the soundproofing body. It also has the effect that it can be done.

According to the soundproof structure of the present invention, the hollow steel pipe and the through pipe not only allow the blast pressure to escape but also act as a side branch type silencer, and the blast escapes. There is also an effect that the sound pressure of a large blast sound generated at that time is greatly reduced.

According to the soundproof wall of the present invention according to claim 6, the steel pipe not only merely releases the blast pressure, but also acts as an orifice type silencer, and generates a large blast sound generated when the blast escapes. Also, the effect that the sound pressure of the sound is greatly reduced is produced.

[0057]

[Brief description of the drawings]

1A and 1B are diagrams of a soundproof structure according to an embodiment, wherein FIG. 1A is a front view, and FIG. 1B is a horizontal cross-sectional view along line AA.

FIGS. 2A and 2B are diagrams of a soundproof structure according to the present embodiment, in which FIG. 2A is a vertical cross-sectional view along the line BB of FIG. 1, and FIG. 2B is a vertical cross-sectional view along the line B′-B ′.

FIG. 3 is a front view of a door panel.

FIG. 4 is a partial cross-sectional view of the soundproof wall, and FIG.
Sectional drawing of the door panel which follows the C line, (b) is sectional drawing of the panel unit which concerns on a modification.

FIG. 5 is a vertical sectional view showing a communication unit according to a modification.

FIG. 6 is an overall perspective view of a soundproof wall according to the related art.

[Explanation of symbols]

 11 soundproof structure 17 round steel pipe (steel pipe) 18 soundproof wall (soundproof body) 19 penetration pipe (communication means) 23 door panel (soundproof body) 41 welding 42 panel unit (soundproof body) 51 L-shaped hollow member (communication means)

Claims (6)

[Claims] 1. A soundproofing device comprising a plurality of steel pipes arranged adjacent to each other in parallel to form a soundproofing body, and a communication means for communicating two spaces separated by the soundproofing body with each other. Soundproof structure. 2. The soundproof structure according to claim 1, wherein two adjacent steel pipes among said steel pipes are welded to each other. 3. The soundproof body according to claim 1, wherein a predetermined number of steel pipes are welded in advance in a juxtaposed state to form a panel unit, and the panel units are connected to each other via predetermined connection means. Item 2. The soundproofing structure according to Item 2. 4. The soundproof structure according to claim 1, wherein said steel pipe is a round steel pipe. 5. The communication means wherein the steel pipe is a hollow pipe, and a through pipe penetrating the soundproof body is connected to the other end of the hollow pipe so as to communicate with a hollow space in the hollow pipe. The soundproof structure according to claim 1. 6. The communication means, wherein the steel pipe is a hollow pipe, and one end of the hollow pipe is provided with a first opening which is open in one space partitioned by the soundproof body, and the hollow pipe is provided with the first opening. 2. The soundproofing structure according to claim 1, wherein the other end of the pipe is provided with a second opening which is opened in the other space partitioned by the soundproofing body.