JP2002146726A - Sound insulating wall - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound insulating wall excellent in the noise attenuation effect and workability when it is constructed. SOLUTION: A recess section 14 as the back air space of a sound absorbing plate 20 is formed in an interior wall surface of a concrete wall 12, and the recess section 14 is formed in the whole interior wall surface and, at the same time, it is favorable that the thickness of the sound insulating wall becomes the extent of 5 to 20 cm in terms of the noise attenuation effect. Ribs 16 and 16 having a plurality of stripes are provided to the interior wall surface of the concrete wall 12 in the horizontal direction, the ribs 16 and 16 have such an original purpose that the ribs hold the strength of the thin concrete wall 12 and, at the same time, the ribs bears such a part that the sound absorbing plate 20 is mounted while ensuring the back air space on the wall surface of the concrete wall 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soundproof wall installed on a side of an expressway or a railway elevated as a soundproofing measure of a vehicle.

[0002]

2. Description of the Related Art Conventionally, a local noise barrier against a noise source such as a noise barrier along a railway, a road side noise barrier, and a multistory parking garage has a support wall made of H steel or the like on a concrete wall cast in place. After being built, the sound-absorbing plate and sound-insulating plate are fixed with clasps. At this time, in order to form an air layer between the sound absorbing plate (or the sound insulating plate) and the concrete wall, a spacing member is often interposed between the two. When such a soundproof wall is installed, for example, along a railway, a sound absorbing plate or the like occupies a limited inner space section, so that it is necessary to secure a space for installation in advance. In addition, there is a problem that the workability is poor because the spacing member, the fastener, and the like are required even in the case of mounting.

The inventors of the present invention have previously described a sound-absorbing panel in which a dam plate and a porous sound-absorbing plate are combined and integrated via an air layer.
A soundproof wall structure including a concrete wall in contact with the weir plate has been proposed (JP-A-2000-8331). The sound-insulating wall according to the present invention uses the sound-absorbing panel as a concrete driving formwork, and uses the concrete wall as a sound-insulating wall. It cannot be denied that advanced technology is required to satisfy construction accuracy during installation.

[0004]

SUMMARY OF THE INVENTION The present invention provides a soundproof wall comprising a transmission / reflection type sound absorbing plate and a concrete wall, which is excellent in noise reduction effect. It is intended to provide.

[0005]

The soundproof wall of the present invention comprises a concrete wall having a concave portion and a rib as a back air layer on the surface, and a porous sound absorbing plate attached to the concrete wall. It is assumed that. Preferably, said concrete wall is a precast concrete wall. It is preferable that the sound absorbing plate is formed by curing an inorganic particulate material and a fibrous filler added as needed with a binder.

[0006]

The plurality of ribs formed on the inner wall surface of the concrete wall reinforce the strength of the thin concrete wall and at the same time secure a back air space. Thus, the generated noise is effectively reduced by the transmission / reflection type sound absorbing plate, the sound insulating concrete wall, and the air layer interposed therebetween.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, as a preferred embodiment of the present invention, a soundproof wall installed on a road or a railway overpass will be described. FIG. 1 shows a soundproof wall 10 erected on an elevated foundation 8.
1 is a partial perspective view showing a soundproof wall 10 constructed by attaching a sound absorbing plate 20 to an inner wall surface of a concrete wall 12. The concrete wall 12 shown in this figure is a precast concrete wall fixed to the elevated foundation 8 with anchor bolts 9, but the concrete wall 12 may be constructed by cast-in-place concrete.

[0008] On the inner wall surface of the concrete wall 12, a concave portion 14 serving as an air layer behind the sound absorbing plate 20 is formed. It is preferable that the concave portion 14 is provided on the entire inner wall surface and has a thickness of about 5 to 20 cm from the viewpoint of a noise reduction effect. On the inner wall surface of the concrete wall 12, a plurality of ribs 16, 16 are provided.
Are provided in the horizontal direction. The ribs 16, 16 have an essential purpose of maintaining the strength of the thin concrete wall 12 and also have a role of attaching the sound absorbing plate 20 to the wall surface of the concrete wall 12 while securing a back air layer. Therefore, there is no limitation on the shape and the number of ribs 16 as long as these functions are satisfied. FIG.
Is a front view of a precast concrete wall 12 as another embodiment, and shows that the present embodiment has two ribs 16, 16 in the vertical direction.

The sound-absorbing plate 20 of the present invention is made of a porous material having continuously formed voids therein, and has a structure in which sound is easily absorbed. Inorganic granules are used as the main material of the sound absorbing plate, and obsidian, pearlite, antifossil, foamed granules of natural stones such as shirasu, or foamed granules of glass or various ceramics are preferable, and these can be used alone or in combination. Used. The particle size of the inorganic particles is preferably about 0.1 to 2 mm.

In the present invention, in order to increase the strength of the sound absorbing plate 20, it is desirable to mix a filler into the sound absorbing material to reinforce the strength of the sound absorbing plate. As the filler, chopped strand, mat, or net-like fibrous materials are preferable, and glass fibers, rock wool, inorganic fibrous materials such as carbon fibers, and organic synthetic fibrous materials such as vinylon and polyester. Can be used. In addition, a prepreg formed by impregnating a fibrous material with a thermosetting resin such as a phenol resin, a polyester resin, an epoxy resin, or a melamine resin, and curing the fiber partially can also be suitably used. The portion to be reinforced with the filler may be at any position near or inside the surface of the sound absorbing plate, or may have any structure of a single layer, two or more layers.

The sound absorbing plate 20 is preferably formed by molding and hardening the inorganic particulate matter and a fibrous filler added as necessary with a binder. As a binder,
Either organic or inorganic binders can be used, but in the case of producing a sound absorbing material by adhering the inorganic particles in a spotted manner, a heat curing temperature in the range of 80 to 200 ° C. It is preferable to use a binder of a conductive resin. Examples of such a synthetic resin include a phenol resin, an epoxy resin, a melamine resin, a urea resin, and a lignin resin, and a phenol resin is particularly preferable. In the case of a phenolic resin, the mixing ratio with respect to the inorganic particulate matter is preferably 1.5 to 25% by weight, particularly preferably 5.0 to 15% by weight. If the content is less than 1.5% by weight, the granular material cannot be firmly bonded to each other or the granular material and the filler, and the strength of the sound absorbing material decreases. On the other hand, if it exceeds 25% by weight, voids between the granular materials are filled, and a porous structure suitable for a sound absorbing material cannot be formed.

In order to manufacture the sound absorbing plate 20, inorganic particulate matter,
The filler and the binder may be simply mixed, or the surface of the inorganic particulate matter may be coated in advance with a binder, and then the filler and a binder to be added as necessary may be mixed. Next, the mixture or the granular material is put in a mold or the like, and if necessary, a lubricant is mixed, and the mixture is heated and pressed to be formed by a dry manufacturing method. Of course, it may be manufactured by a wet manufacturing method. The porosity of the sound absorbing material obtained in this way is 5 to 75%, preferably about 10 to 50%.
The porosity can be adjusted by appropriately selecting the type and blending ratio of the inorganic particulate matter, the filler and the binder, or the production method such as the pressing pressure and temperature conditions.

The sound absorbing plate 20 is attached to the concrete wall 12 by a rectangular metal frame 18, and the concrete walls 12, 12
.. Are continuously erected to construct a side noise barrier along a road or a railway overpass.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a viaduct 6 shown in a sectional view in FIG.
The sound reduction effect by the soundproof wall 10 was measured. The soundproof wall 10 is one in which the sound absorbing plate 20 is attached to the inner wall surface of the concrete wall 12 described above, and the noise level when the train passes at various train speeds is measured at a measurement point M outside the soundproof wall 10.
The results are shown in FIG. Also, for comparison,
The noise level was measured with only the concrete wall 12 from which the sound absorbing plate 20 was removed, and the result is indicated by a square in FIG. From the results of both measurements, the noise level of the soundproof wall 10 to which the sound absorbing plate 20 was attached was reduced by 3 dB to 5 dB, and a noise reduction effect was recognized.

[0015]

According to the first aspect of the present invention, since the concave portion and the rib as the back air layer are formed on the inner wall surface of the concrete wall, the weight and thickness of the soundproof wall structure can be reduced. In addition, since a structure in which the sound absorbing plate is directly attached to the ribs is employed, no extra hardware such as mounting hardware and spacers is required, and the workability is excellent and the cost is extremely advantageous. In addition, the sound absorbing plate can be easily mounted, and even if it is damaged, it can be easily replaced or the specification can be changed. Furthermore, since the soundproof wall surface has a smooth structure, it does not hinder traffic and work on the side of the wall, and by treating or painting the smooth surface, the scenery and beauty can be improved. Has side effects.

According to the second aspect of the present invention, the soundproof wall is made of a precast concrete having a light weight and a thin structure, whereby the thickness of the concrete wall can be further reduced and the construction can be performed without enlarging the entire space. Because of this, it is excellent in workability. The soundproof wall according to claim 3 has a particularly remarkable noise reduction effect.

[Brief description of the drawings]

FIG. 1 is a partial perspective view of a soundproof wall according to the present invention.

FIG. 2 is a front view of a precast concrete wall as another embodiment.

FIG. 3 is a cross-sectional view of a viaduct in which a sound reduction effect by a soundproof wall is measured.

FIG. 4 is a graph showing a measurement result of a noise level in the example.

[Explanation of symbols]

 Reference Signs List 10 soundproof wall 12 concrete wall 14 recess 16 rib 18 metal frame 20 sound absorbing plate

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Nobuyuki Murata 2-1 Tsukudo-cho, Shinjuku-ku, Tokyo Headquarters of Kumagaya Gumi Tokyo Co., Ltd. (72) Inventor Masaji Hata 2-1 Tsukudo-cho, Shinjuku-ku, Tokyo Kumagai Gumi Tokyo Head Office (72) Inventor Seiichi Kondo 2-1, Tsukudo-cho, Shinjuku-ku, Tokyo Fukushima (Tokyo) F-term (Reference) 2D001 BA02 CA01 CB01 CB05 CD03 CD04 5D061 AA13 AA25 BB24 BB37 DD06 DD07

Claims (3)

[Claims] 1. A soundproof wall comprising a concrete wall having a concave portion and a rib as a back air layer on a surface thereof, and a porous sound absorbing plate attached to the concrete wall surface. 2. The soundproof wall according to claim 1, wherein said concrete wall is a precast concrete wall. 3. The sound-insulating wall according to claim 1, wherein the sound-absorbing plate is formed by curing an inorganic particulate matter and a fibrous filler added as required with a binder.