JPH1179865A - Sound-absorbing body, and sound-absorbing and sound-insulating structure by using the sound-absorbing body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a light and cheap sound-absorbing body having high sound- absorbing characteristics, and to provide a sound-absorbing and sound-insulating structure by utilizing the sound-absorbing body. SOLUTION: This sound-absorbing body is obtained by uniformly mixing 100 pts.vol. cement paste obtained by mixing and stirring a mixture of 100 pts.wt. cement with 0.5-1 pts.wt. inorganic binder represented by the one formed into powder by water granulation of hormite mineral, 5-20 pts.wt. calcium aluminate-based light-weight aggregate, 0.2-0.5 pts.wt. water reducing agent for a cement, represented by melamine sulfonated condensate, with 35-50 pts.wt. water, with 300-600 pts.vol. ultra light-weight aggregate obtained by pulverizing a foamed synthetic resin hardened material and having 2-8 mm particle diameter, pouring the mixed product into a mold and hardening the poured mixed product. The sound-absorbing and sound-insulating body 1 is obtained by combining the sound-absorbing body 5 with a sound-insulating body 4 made of a concrete.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound absorbing body suitably used for walls and ceilings, and a sound absorbing / sound insulating structure capable of exhibiting both sound absorbing and sound insulating functions by using the sound absorbing body. It is about.

[0002]

2. Description of the Related Art Conventionally, for example, panels using glass wool or rock wool,
Those using concrete blocks are used.
That is, the former is one in which a sound absorbing material such as glass wool or rock wool is filled and arranged between a metal sound insulating plate and a perforated plate, and has both a sound absorbing function by the glass wool and a sound insulating function by the sound insulating plate. I have. On the other hand, the latter is formed by laminating a large number of concrete blocks having open cells in contact with the front surface of a concrete wall having a sound insulation function, and has a sound absorbing effect by the open cells formed on the surface and inside of the concrete block. It can be demonstrated.

[0003]

However, since the former uses a large number of parts and uses a metal plate or wool which is troublesome to manufacture, there is a certain limit in reducing the cost. The latter, on the other hand, makes the concrete blocks relatively small, as is well known, due to the increased weight. Therefore, there is a problem that a large number of man-hours are required for the lamination work on site. Although porous lightweight concrete blocks using lightweight aggregates such as perlite and vermiculite have been developed, the advent of lighter and cheaper sound absorbing materials is desired.

[0004]

In order to solve the above-mentioned problems, the present invention uses an ultralight aggregate having a particle size of 2 to 8 mm obtained by crushing a cured foamed synthetic resin as an aggregate. These ultra-light aggregates are uniformly coated with an inorganic material and bonded in a point contact state. In order to realize such a structure, formite mineral is used as a cement paste with respect to 100 parts by weight of cement. 0.5 to 1 part by weight of an inorganic thickener typified by granulation into a powder, 5 to 20 parts by weight of a calcium aluminate fine-grained lightweight aggregate, cement represented by melamine sulfonation condensation Water reducing agent 0.
1 to 0.5 parts by weight, water is added to
It is characterized by using a mixture obtained by mixing and stirring 5 to 50 parts by weight.

[0005] Further, the present invention provides, as an aggregate, a particle size of 2 to 8 mm obtained by pulverizing and heat-treating a foamed synthetic resin cured product.
Of ultra-light aggregates, and these ultra-light aggregates are uniformly coated with an inorganic material and bonded in a point contact state. To realize such a structure, 100 parts by weight of cement is used as a cement paste. On the other hand, 0.5 to 1 part by weight of an inorganic thickener represented by a powder obtained by granulating a formite mineral, 5 to 20 parts by weight of calcium aluminate-based fine aggregate, 5 to 20 parts by weight of melamine sulfon It is characterized by using a mixture obtained by mixing and stirring 35 to 80 parts by weight of water into a mixture prepared to be 0.1 to 0.5 parts by weight of a cement water reducing agent represented by chemical condensation.

[0006] Further, the present invention provides a combination of the above sound absorber with a concrete sound insulator.
It is an object of the present invention to provide a sound absorbing / sound insulating structure having high soundproof performance. That is, the invention of the sound absorbing / sound insulating structure,
This corresponds to the invention of a product exclusively utilizing the specific properties of the sound absorber.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The sound absorber according to the present invention comprises 0.5 to 1% by weight of an inorganic thickener represented by a powder obtained by granulating formite mineral with respect to 100 parts by weight of cement. 35 to 5 parts by weight of a calcium aluminate-based lightweight aggregate and 0.1 to 0.5 parts by weight of a cement water reducing agent represented by a melamine sulfonated condensate. -100 parts by weight of the cement paste obtained by mixing and stirring is uniformly mixed with 300 to 600 parts by weight of an ultralight aggregate having a particle size of 2 to 8 mm obtained by pulverizing a cured synthetic resin. It is obtained by driving into a frame and curing.

Further, the sound absorber according to the present invention is a cement 1
For 100 parts by weight, 0.5 to 1 part by weight of an inorganic thickener typified by granulating and powdering formite mineral, 5 to 20 parts by weight of calcium aluminate-based fine-grained lightweight aggregate, 0.1 to 0.5 parts by weight of a cement water reducing agent typified by a melamine sulfonated condensate, and 35 to 80 parts by weight of water mixed and stirred with 100 parts by volume of a cement paste obtained by mixing and stirring. , An ultralight aggregate 30 having a particle size of 2 to 8 mm obtained by crushing and heat-treating a cured synthetic resin foam
It is obtained by uniformly mixing with 0 to 600 parts by volume, driving into a mold, and curing.

In other words, this sound absorbing material is continuously coated with a cement paste having a thickness of 0.5 to 2 mm on the surface of each ultra-light aggregate, and the resulting material is cast into a mold and cured. Voids are 20-40% of the cured product
It was molded so that Here, the inorganic thickener is used to coat the cement paste with a uniform thickness on the surface of the ultralight aggregate by imparting adhesion and viscosity to the cement paste. The reason for using 0.5 to 1 part by weight of the inorganic thickener with respect to 100 parts by weight of cement is that if the amount is less than 0.5 part by weight, the surface of the ultralight aggregate is appropriately coated with cement paste. If the amount exceeds 1 part by weight, the coating thickness becomes excessively large and the porosity becomes unduly small.

[0010] The calcium aluminate-based fine lightweight aggregate is used for a role as a viscosity aid, and for the purpose of reducing the weight of the cement paste and suppressing cracking. The reason why the ground material is used as the ultra-light aggregate is that the cement paste adheres better than when using a bead-like material having a smooth surface. There is an advantage that it is hard to separate from

In order to further improve the durability of the paste, such as water resistance and adhesion, a water-dispersible resin solution, particularly a polymer resin emulsion represented by an acrylic resin emulsion, is added to a cement weight of 5%. It is desirable to mix up to 15%. Further, when it is desired to mix the cement paste and the ultra-light aggregate obtained by grinding particularly homogeneously, an anionic surfactant such as alkylnaphthalene sulfonate, or a nonionic surfactant is further added to the paste composition. It is preferable to mix a foaming agent composed of an activator so that the amount of bubbles inside is 5 to 15%. That is, when such a foaming agent is introduced, the cement paste can be made into a soft cream-like one into which a large number of fine bubbles are introduced. Therefore, when the cement paste and the ultralight aggregate are kneaded, the cement paste is rich in adhesiveness, and the entire outer surface of the ultralight aggregate can be uniformly coated with the cement paste. Becomes In addition, it is possible to more reliably eliminate the problem that only the ultralight aggregate is unevenly distributed on the upper portion due to a difference in specific gravity from the cement paste.

Further, in order to reinforce the entire molded sound absorbing body, it is preferable to provide a reinforcing mesh inside. The reinforcing mesh is preferably set in the mold when the cement paste is driven into the mold. Regarding the material,
A synthetic resin mesh represented by polypropylene or the like, or a metal mesh such as stainless steel is particularly preferable in terms of durability and ease of handling.

[0013] In view of the importance of resource recycling for the purpose of preserving the global environment, it is desirable to crush the styrene foam waste generated in large quantities without interruption to produce ultralight aggregates. The sound-absorbing / sound-insulating structure of the present invention using the above-described sound-absorbing body includes a concrete sound-insulating body having a concave portion on one surface, and the above-described sound absorbing member disposed in the concave portion of the sound insulating member. It is suitably used for soundproof walls and the like.

In this case, in order to expect a sound-absorbing effect utilizing a resonance phenomenon in addition to the sound-absorbing action based on the flow resistance of the open cell, the depth of the recess is set to be larger than the thickness of the sound-absorbing body. Preferably, a cavity is formed between the inner surface of the sound absorber and the bottom surface of the concave portion facing the inner surface. For ease of assembly or to simplify replacement work when the sound absorbing body is damaged, the sound insulating body is made into a plate-like structure that can be stacked up and down to form a wall, It is preferable that the concave portion is provided so as to be opened at one of the upright surface and the upper end surface of the sound insulating body, and the sound absorber is slidably engaged with the concave portion from the upper end surface side.

In order to simplify the structure,
It is a matter of course that the above-mentioned sound absorbing body may be simply attached to one side of a concrete sound insulating body.

[0016]

Examples Examples of Sound Absorber A cement paste and an ultralight aggregate were mixed and kneaded, and the mixture was poured into a mold to obtain a plate-like sound absorber. Details of the cement paste and the ultra-light aggregate are as follows.

Nine types of cement paste were prepared as shown in Table 1 below. That is, Table 1
In P-2, cement, water, fine lightweight sand as a calcium aluminate-based fine lightweight aggregate, formite powder as an inorganic thickener, and a water reducing agent are blended, and air is entrained. P-1, P-3, and P-4 are further mixed with a foaming agent and kneaded to form a soft cream. P-6 and P-7 are obtained by further adding an acrylic resin emulsion which is a water-dispersible resin liquid. Further, P-8 and P-9 are obtained by changing the water cement ratio without using a foaming agent. The units in the table are parts by weight.

[0018]

[Table 1]

As ultra-light aggregates, P-1 to P-6 are:
Styrofoam waste material has a particle size of 8mm by crusher
Using Styrofoam crushed sand pulverized to become the following, P-7 to P-9 coarsely pulverized waste of Styrofoam by a crusher, and crushed Styrofoam secondary to 8 mm or less by a crusher again with heat-treated Styrofoam It uses sand. The crushed styrene foam crushed sand or the crushed and heat-treated styrene foam crushed sand was uniformly mixed with the cement paste and poured into a mold to obtain 15 types of sound absorbing materials as shown in Table-2.

[0020]

[Table 2]

Here, A, B,
C shows that A is good, B can be molded even if it is a little rough, and C shows that it takes a lot of time to hold down the molding and is defective. When the calcium aluminate-based fine aggregate exceeds 20% of the weight of the cement, the strength of the sound absorbing material is remarkably reduced, the viscosity of the paste is reduced, and the paste becomes lumpy and molding is difficult.

The amount of fine bubbles in the paste is also 1
If it exceeds 5%, the strength is greatly reduced, and the surface of the cured product is undesirably powdery. Next, the mixing ratio of the styrene foam crushed sand or the crushed and heat-treated styrene foam crushed sand to the paste component is excellent in that the volume ratio of 1: 3 to 1: 4 uniformly forms continuous voids, It is also stable in terms of strength. On the other hand, when the ratio is less than 1: 3, the porosity extremely decreases,
Not preferred. As for the sound absorbing performance as a sound absorbing material, a block type thing has a continuous porosity of preferably 25% to 3%.
About 5%, there is a lot of interference by mortar with styrene,
Efficiency is due to fine continuous voids. The results obtained in consideration of these facts are the above examples.

The sound absorbing performance of these sound absorbing bodies is shown in Table 3 below. The numerical values in the table indicate the results measured by the reverberation room method defined in JIS A1409, that is, the reverberation room method sound absorption coefficient. The sound absorbing material having a thickness of 50 mm was used.

[0024]

[Table 3]

Embodiment Regarding Sound Absorbing / Sound Insulating Structure In the embodiment shown in FIGS. 1 to 4, a sound absorbing / sound insulating structure 1 for constructing a soundproof wall 2 or the like of a highway using the above-described sound absorbing body. It is composed. That is, as shown in FIGS. 1 and 2, the sound absorbing / sound insulating structure 1 includes a sound insulating body 4 having a concave portion 3 on one surface and a concave portion 3 of the sound insulating body 4.
And a sound absorbing body 5 attached to the vehicle.

The sound insulator 4 is provided with a prestressed concrete structure or a reinforced concrete structure, has a long and narrow rectangular shape on the left and right sides, and has a groove-shaped recess 3 opening on one side and both right and left end faces. I have. The concave portion 3 has a dovetail shape in which the vertical width of the opening end is set slightly smaller than the vertical width of the bottom portion, and has the same composition as described in the first or second embodiment in the concave portion 3. A sound absorber 5 is provided. The sound absorber 5 is formed by directly kneading cement-based mortar and ultra-light aggregate into the recess 3 using the sound insulator 4 instead of a mold.
An insert nut 7 used for temporarily screwing a hook fitting 6 for lifting the sound absorbing / sound insulating structure during transportation or construction on the upper surface and the lower surface of the sound insulating body 4.
Is buried.

The sound insulating member 4 and the sound absorbing member 5 may be manufactured separately and combined in the final step. FIGS. 3 and 4 show an example of a case where a soundproof wall 2 is constructed by using a plurality of the sound absorbing / sound insulating structures 1. The soundproof wall 2 has H-shaped supports 8 in plan view having concave grooves 8a on both sides thereof erected at predetermined intervals along a road. For example, six sound absorbing / sound insulating structures 1 are provided between the respective supports 8.
The groove 8a of the column 8 corresponding to each of both side end portions 1a
It is interposed in a state where it is fitted to. In FIG. 1, the left half of the sound-absorbing / sound-insulating structure 1 is shown with the sound-absorbing body 5 omitted.

The sound absorbing / sound insulating structure 101 shown in FIGS.
Is, in addition to the sound insulator 4 and the sound absorber 5 similar to those described above,
A decorative plate 110 for covering and covering the sound absorbing body 5 is provided. The decorative plate 110 is made of, for example, a sheet metal, has a louver portion 110a having air permeability, and its upper end and lower end are fixed to the front surface of the sound insulating body 4 using screws 110b. In FIG. 5, the right half of the sound absorbing / sound insulating structure 101 is not illustrated with the decorative plate 110 being omitted.

The sound absorbing / sound insulating structure 201 shown in FIGS.
Is obtained by separately manufacturing and combining the sound insulator 204 and the sound absorber 205. That is, on both upper and lower inner surfaces of the groove-shaped concave portion 203 of the sound insulating body 204, ridges 203a having a V-shaped cross section are formed.
5, a concave groove 205a having a V-shaped cross section is formed on both upper and lower end surfaces. Then, the sound absorbing body 205 is fitted into the concave groove 205a with the ridge 203a,
The sound insulating body 204 is slidably engaged in the recess 203 from one end in the longitudinal direction.

The sound absorbing / sound insulating structure 201 includes the sound insulating body 2
The depth of the recess 203 of the sound absorber 204 is set to be larger than the thickness of the sound absorber 205, and a cavity is formed between the inner surface 205b of the sound absorber 205 and the bottom surface 203b of the recess 203 facing the inner surface 205b. 210 are formed. If the cavity 210 is unnecessary, the sound absorber 2
Needless to say, the thickness dimension of the recess 05 and the depth dimension of the recess 203 may be set to be substantially equal.

The sound absorbing / sound insulating structure 3 shown in FIGS.
01 is the same as that shown in FIGS.
And the sound absorber 305 are separately manufactured and combined. That is, the sound insulator 304 is provided with a plurality of recesses 303 opened in one of the upright surface 304a and the upper end surface 304b. Is engaged. Protrusions 303a having a V-shaped cross section are formed on both left and right inner surfaces of each concave portion 303 of the sound insulator 304, and V-shaped cross sections are formed on both left and right end surfaces of each sound absorber 305. A concave groove 305a is formed. And
Each of the sound absorbers 305 is inserted into the groove
a so that the upper end surface 30 of the sound insulating body 304 is
The sliding engagement is made from the 4b side into the corresponding concave portion 303.

The sound absorbing / sound insulating structure 301 is also provided with the sound insulating body 3.
04 has a depth dimension larger than the thickness dimension of the sound absorber 305, and a cavity is provided between the inner surface 305b of the sound absorber 305 and the bottom surface 303b of the recess 303 facing the inner surface 305b. 310 are formed. In FIG. 10, the left half of the sound absorbing / sound insulating structure 301 is not illustrated with the sound absorbing body 305 omitted. Also in this embodiment, when the cavity 310 is unnecessary, the sound absorber 3
Needless to say, the thickness dimension of the recess 05 and the depth dimension of the recess 303 may be set to be substantially equal.

The sound absorbing / sound insulating structure 401 shown in FIG.
The sound absorbing body 405 is attached to a flat surface of the sound insulating body 404 by an appropriate method, so that the structure can be simplified.

[0034]

According to the sound absorber of the present invention, each of the ultra-light aggregates obtained by crushing a cured foamed synthetic resin such as styrene foam or crushing and heat-treating the cured foamed synthetic resin can be used. It has a structure in which it is uniformly wrapped by the hardened material of the cement paste and is connected to each other in a point contact state, and has continuous voids therein at a rate of about 20 to 40%. Therefore, according to the present invention, it is possible to provide a sound absorber that is extremely lightweight and easy to handle, and that has excellent sound absorption characteristics. Therefore, the sound absorber according to the present invention can be suitably used not only as a soundproof wall of a highway, but also as a wall material or a floor material of a building. It can be used without difficulty as a ceiling material. Also,
Such a sound absorbing material also has fire resistance because each ultralight aggregate is uniformly coated with the inorganic cement paste.

Further, a material further mixed with a water-dispersible resin such as an acrylic resin not only can improve the adhesive strength of the cement paste, but also has particularly good water resistance, and is suitable for outdoor use. It becomes something.
Further, when using a cement paste in which the proportion of air bubbles mixed with an anionic surfactant such as an alkyl naphthalene sulfonate or a non-ionic surfactant is 5 to 15%, In particular, a large amount of air can be entrained finely, and can be kneaded into a soft cream. Therefore, the specific gravity of the cement paste can be made as small as possible, and even if an ultra-light aggregate is added and kneaded therein, the cement paste is rich in adhesive strength, The problem that the ultralight aggregate is biased upward due to the difference in specific gravity can be effectively suppressed, and when using hard styrene that has been heat-treated, the paste is substantially uniformly adhered to the styrene surface. By mixing as described above so that the continuous voids are not filled with the paste, it is possible to obtain a high-quality sound absorber in which ultralight aggregates are uniformly dispersed.

Further, if a synthetic resin mesh or a metal mesh is provided inside, the strength of the sound absorbing body can be increased, so that the handling becomes easier, and the sound absorbing body is formed into a relatively thin shape to be practically used. It is also possible to make it. The use of Styrofoam waste as an ultra-light aggregate not only makes it possible to effectively use waste resources that are in short supply, but is not only economically advantageous but also contributes to the preservation of the global environment. Gain.

Further, if such a sound absorbing body is combined with a sound insulating body made of concrete, it is possible to construct a sound absorbing / sound insulating structure suitable for constructing a soundproof wall or the like of a highway. By using such a sound absorbing body, the weight of the sound absorbing / sound insulating structure itself can be reduced, and not only transportation and construction can be facilitated, but also a tall soundproof wall can be easily constructed.

The sound absorbing / sound insulating structure can use open cells formed in the cement composition of the sound absorbing body as flow resistance inducing means for exhibiting a sound absorbing action. If a cavity is formed between the inner surface of the sound absorbing body and the bottom surface of the concave portion facing the inner surface, the cavity can be further used as a resonance space for silencing using a resonance effect. Therefore, by appropriately selecting the volume of the cavity, it is possible to particularly improve the soundproofing effect against sound of a specific frequency.

Further, a concave portion of the sound insulating body is provided so as to be opened on one of the upright surface and the upper end surface of the sound insulating member, and the sound absorbing body is slidably engaged with the concave portion from the upper end surface side. For example, only by stacking a plurality of sound insulators, each sound absorber can be fixed to the sound insulator so as not to fall off. In addition, if a specific sound absorber is damaged,
It is possible to replace the damaged sound absorber with a new one simply by slightly lifting the sound insulation structure. Therefore, it is possible to construct a soundproof wall that is easy to maintain as well as to construct.

[Brief description of the drawings]

FIG. 1 is a front view partially showing another embodiment of the present invention;

FIG. 2 is an enlarged sectional view taken along line AA in FIG.

FIG. 3 is an overall plan view showing the embodiment.

FIG. 4 is an overall front view showing the embodiment.

FIG. 5 is a front view partially showing another embodiment of the present invention;

FIG. 6 is an enlarged sectional view taken along line BB in FIG. 5;

FIG. 7 is an overall front view showing the embodiment.

FIG. 8 is a front view showing a still further embodiment of the present invention with a part being omitted;

FIG. 9 is an enlarged sectional view taken along line CC in FIG. 8;

FIG. 10 is a front view showing a still further embodiment of the present invention with a part being omitted;

FIG. 11 is a partial plan view showing the embodiment.

12 is a sectional view taken along line DD in FIG.

FIG. 13 is an overall front view showing the embodiment.

FIG. 14 is an enlarged cross-sectional view corresponding to FIG. 2, showing still another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Sound absorption / sound insulation structure 1a ... Side end part 2 ... Sound insulation wall 3 ... Recessed part 4 ... Sound insulation 5 ... Sound absorption body 6 ... Hook metal fitting 7 ... Insert nut 8 ... Prop 8a ... Concave groove 101 ... Sound absorption / sound insulation structure 110: decorative board 110a: louver part 110b: screw 201: sound absorbing / sound insulating structure 203: concave part 203a: ridge 203b: bottom surface 204: sound insulating body 205: sound absorbing body 205a: concave groove 205b ... inner surface 210: cavity 301: sound absorbing・ Sound insulation structure 303 ... Concave part 303a ... Protrusion ridge 304 ... Sound insulation body 304a ... Standing surface 304b ... Top surface 305 ... Sound absorber 305a ... Concave groove 310 ... Cavity 401 ... Sound absorption / sound insulation structure 404 ... Sound insulation body 405 ... Sound absorber

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI E04B 1/86 E04B 1/86 D // (C04B 28/02 16:08 14:04 24:30 14:02) 111: 52 (72) Inventor Setsuharu Hideshima 4-1111-50 Matsumi-cho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture 406 406 Towa Myorenji Corp. (72) Inventor Kazuya Nishimura 3-12-14, Wakaizumi, Honjo-shi, Saitama (72) Inventor Koji Noguchi 6-6, Umezu Owanaba-cho, Ukyo-ku, Kyoto-shi, Kyoto Arashiyama Royal Heights Building No. 3 1003 (72) Inventor Kojiro Yuki 2-10-22 Misonocho, Kodaira-shi, Tokyo (72) Inventor Koichi Nagase Kanagawa Prefecture 4466-15 Izumi-cho, Izumi-ku, Yokohama-shi

Claims (11)

[Claims] 1. An inorganic thickener represented by a powder obtained by granulating a formite mineral in an amount of 0.5 to 1 part by weight with respect to 100 parts by weight of cement, and a calcium aluminate-based fine lightweight aggregate. 5 to 20 parts by weight, 0.1 to 0.5 parts by weight of a cement water reducing agent represented by a melamine sulfonated condensate,
100 parts by volume of a cement paste obtained by mixing and stirring 35 to 50 parts by weight of water into a mixture prepared so as to obtain an ultralight aggregate 300 having a particle size of 2 to 8 mm obtained by crushing a cured foamed synthetic resin. A sound absorber characterized by being uniformly mixed in a volume of up to 600 parts, driven into a mold, and cured. 2. 100 parts by weight of cement, 0.5 to 1 part by weight of an inorganic thickener represented by powdery granulation of formite mineral, calcium aluminate based fine aggregate 5 to 20 parts by weight, 0.1 to 0.5 parts by weight of a cement water reducing agent represented by a melamine sulfonated condensate,
100 parts by volume of a cement paste obtained by mixing and stirring 35 to 80 parts by weight of water with a mixture prepared so as to obtain a particle size of 2 to 8 m obtained by crushing and heating a cured foamed synthetic resin.
A sound absorber characterized by being uniformly mixed with 300 to 600 parts by volume of an ultralight aggregate having a diameter of m and then being driven into a mold and cured. 3. The cement paste according to claim 1, wherein a water-dispersible resin solution such as an acrylic resin is added to the paste composition in an amount of 5 to 15 parts by weight based on 100 parts by weight of the cement. Sound absorber. 4. The cement paste is further mixed with an anionic surfactant such as an alkylnaphthalene sulfonate or a foaming agent comprising a nonionic surfactant in the above-mentioned paste composition. 4. The sound absorber according to claim 1, wherein the sound absorber is adjusted to be 15%. 5. A reinforcing mesh internally provided, wherein the reinforcing mesh is a synthetic resin mesh represented by polypropylene or the like set in the mold when the cement paste is poured into the mold, or 5. The sound absorber according to claim 1, which is a metal mesh such as stainless steel. 6. The sound absorber according to claim 1, wherein the ultralight aggregate is obtained by crushing waste material of styrofoam. 7. The sound absorber according to claim 2, wherein the ultralight aggregate is obtained by crushing and heating a waste material of styrofoam. 8. A sound insulator made of concrete having a concave portion on one surface, and disposed in the concave portion of the sound insulator.
A sound-absorbing / sound-insulating structure, comprising: the sound-absorbing body according to 2, 3, 4, 5, 6, or 7. 9. A depth dimension of the concave portion is set to be larger than a thickness dimension of the sound absorber, and a cavity is formed between an inner surface of the sound absorber and a bottom surface of the concave portion facing the inner surface. A sound absorbing / insulating structure according to claim 8. 10. The sound insulator is a plate-like member configured so that a plurality of sound insulators can be vertically stacked to form a wall, and the recessed portion is opened on one of the upright surface and the upper end surface of the sound insulator. The sound absorbing / sound insulating structure according to claim 8 or 9, wherein the sound absorbing body is slidably engaged with the concave portion from the upper end surface side. 11. A sound insulator made of concrete, and a sound insulator provided on one surface of the sound insulator.
And a sound absorber characterized by comprising:
Sound insulation structure.