Resin foam block and vibration reduction structure

Abstract

To provide a resin foam block capable of effectively reducing vibrations in a wide vibration frequency band, ranging from low to high vibration frequency bands, and a vibration reduction structure excellent in vibration reduction performance while eliminating the need for large scale construction.SOLUTION: Resin foam blocks 10, 30 installed in the underground G and reducing vibrations to be propagated through the underground G comprises a resin foam body 11 in a rectangular parallelepiped shape or a generally rectangular parallelepiped shape, wherein air gaps 15 for reducing rigidity are arranged in the resin foam body 11. For a vibration reduction structure 60, a plurality of resin foam blocks 30 are arranged on at least a side surface 50a facing a vibration source of the underground structure 50.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a resin foam block and a vibration reducing structure. [Background technology]

[0002] In buildings (or structures), microtremors occur normally due to so-called environmental vibrations, such as the microtremors of the earth itself, traffic vibrations caused by the movement of vehicles, including railways, vibrations during the operation of factory facilities, and vibrations caused by wind loads, and during earthquakes, vibrations with larger amplitudes than the microtremors generally occur depending on the scale of the seismic motion. Considering that residents are exposed to the vibrations of buildings during earthquakes as well as the presence or absence of building damage and the impact on the living environment at the above-mentioned normal microtremor levels on a daily basis, it is extremely important to reduce such environmental vibrations.

[0003] As a measure to reduce vibrations that propagate through the ground, including the above-mentioned environmental vibrations, a common practice is to install an air trench in the ground between the vibration source and the target building, and such an air trench is sometimes called an anti-vibration trench, etc. By installing this air trench in the ground, it is possible to significantly reduce the vibrations that propagate from the vibration source to the building.

[0004] On the other hand, since an empty trench is constructed at a certain depth underground with a certain horizontal alignment, the construction cost and construction period are issues. In addition, there is concern about the collapse of the trench walls, which directly leads to the subsidence of the surrounding ground, so protective measures are required to prevent the trench walls from collapsing, which also leads to a rise in construction costs.

[0005] In this way, instead of constructing an empty trench, which has a high vibration reduction effect but requires large-scale construction, an EPS (Expanded Poly-Styrol) construction method is sometimes applied, in which low-density polystyrene foam blocks (an example of a resin foam block) are installed on the sides and underside of an underground structure to surround the foundation. Polystyrene foam is lightweight and therefore easy to construct, and has various advantages such as excellent compression resistance, water resistance, weather resistance, and self-supporting properties. However, since polystyrene foam blocks have high rigidity, the inventors have identified that while a vibration reduction effect is observed in a high frequency band of, for example, 10 Hz or more, a vibration reduction effect cannot be expected in a low frequency band of a few Hz less than 10 Hz.

[0006] In view of the above, there is a demand for a resin foam block that is installed underground to reduce vibrations that propagate through the ground while eliminating the need for large-scale construction, and which can effectively reduce vibrations over a wide range of frequency bands from low to high, as well as a vibration reduction structure that includes this resin foam block.

[0007] Here, Patent Document 1 proposes a vibration-proof structure for a building. This vibration-proof structure for a building includes a foundation of the building and a vibration-proof material made of a synthetic resin foam that is installed so as to cover at least one outer surface of the foundation. The vibration-proof material has a compressive creep deformation rate of less than 5% with respect to the applied surface pressure, and is stable even when the surface pressure is 2.0 t / m 2 If it is less than this, the shear wave propagation speed will be 125m / s or less and the surface pressure will be 2.0t / m 2 Greater than 10.0t / m 2 If the shear wave propagation velocity is greater than 125 m / s and is less than 220 m / s, the surface pressure is 10.0 t / m 2 Larger than 40.0t / m 2 If the shear modulus is less than 220 m / s, the shear modulus is set so that the shear wave propagation velocity is greater than 220 m / s and less than or equal to 325 m / s. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2022-146635 A Summary of the Invention [Problem to be solved by the invention]

[0009] According to the vibration-proof structure for buildings described in Patent Document 1, the structure is provided with a vibration-proof material made of synthetic resin foam with multiple shear wave propagation velocities set according to surface pressure, which makes it possible to ensure ease of construction while achieving good vibration-proofing effects. However, Patent Document 1 does not provide a resin foam block that can effectively reduce vibrations over a wide frequency range from low to high frequencies, as described above.

[0010] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a resin foam block that can effectively reduce vibrations over a wide frequency range from low to high, and a vibration reduction structure that has excellent vibration reduction properties while eliminating the need for large-scale construction. [Means for solving the problem]

[0011] In order to achieve the above object, one embodiment of the resin foam block according to the present invention is A resin foam block that is installed underground and reduces vibrations propagating underground, A resin foam body having a rectangular parallelepiped or approximately rectangular parallelepiped shape, The resin foam body is characterized in that it has rigidity-reducing voids formed therein.

[0012] According to the present embodiment, rigidity-reducing voids are provided in the rectangular or approximately rectangular resin foam body, so that in addition to the inherent light weight, compression resistance, water resistance, weather resistance, and self-supporting properties of the resin foam body, vibration reduction properties are achieved over a wide range of frequency bands from low to high while maintaining a certain level of rigidity.

[0013] Here, examples of materials for forming the resin foam body include expanded polystyrene (EPS), etc. In addition, the term "approximately rectangular parallelepiped shape" includes shapes in which the corners of a rectangular parallelepiped are chamfered, and shapes in which the left and right end faces of a flat block are recessed inward, such as a concrete block.

[0014] The rigidity-reducing voids provided in the resin foam body can have various forms, including one or more through holes penetrating a pair of opposing side surfaces of the resin foam body, and one or more spherical, egg-shaped, or other hollow forms formed inside the resin foam body.

[0015] In another embodiment of the resin foam block according to the present invention, The resin foam body has a plurality of side surfaces, a top surface, and a bottom surface, The rigidity reducing void penetrates the resin foam body and faces the top end surface and the bottom end surface, A resin foam plate is fixed to each of the top end surface and the bottom end surface to close the rigidity reducing gap.

[0016] According to this embodiment, one or more rigidity-reducing voids that penetrate the resin foam body and expose its top and bottom end surfaces are blocked by fixing resin foam boards to the top and bottom end surfaces, which prevents soil from entering the rigidity-reducing voids, which are through holes, when the resin foam block is installed underground.

[0017] Moreover, one aspect of the vibration reduction structure according to the present invention is The underground structure is characterized in that a plurality of the resin foam blocks are arranged on at least the side facing the vibration source.

[0018] According to this aspect, by arranging multiple resin foam blocks of the present invention on at least the side of an underground structure facing the vibration source, the multiple resin foam blocks can effectively reduce vibrations propagating from the vibration source through the ground, while eliminating the need for large-scale construction.

[0019] Here, examples of underground structures include foundations of buildings such as detached houses, buildings, apartment buildings, etc. Furthermore, "arranging resin foam blocks on at least the side surface facing the vibration source" includes a form in which a plurality of resin foam blocks are arranged only on the side surface facing the vibration source, a form in which a plurality of resin foam blocks are arranged around the entire circumference of the underground structure, a form in which a plurality of resin foam blocks are arranged around the entire circumference of the underground structure as well as the entire area of ​​the bottom surface of the underground structure, etc.

[0020] Another aspect of the vibration reduction structure according to the present invention is A plurality of the resin foam blocks are disposed below an underground structure, and the rigidity reducing voids of the resin foam blocks are filled with soil; The present invention is characterized in that a plurality of the resin foam blocks are arranged on the sides of the underground structure.

[0021] According to this aspect, the rigidity reducing voids of the resin foam block disposed below the underground structure are filled with soil, so that the rigidity reducing voids provide vibration reduction in a wide frequency range, and the underground structure is able to stably support the load. Note that for the resin foam block disposed to the side of the underground structure, since the underground structure does not need to support the load, there is no need to fill the rigidity reducing voids with soil.

[0022] In another aspect of the vibration reducing structure according to the present invention, a plurality of the rigidity-reducing voids are provided in the resin foam body, and partition walls are provided between adjacent rigidity-reducing voids; The resin foam blocks are arranged side by side with their partition walls offset from one another.

[0023] According to this embodiment, the resin foam body has rigidity-reducing voids on the left and right sides of the partition wall, and multiple resin foam blocks are placed side by side in the ground with both partition walls offset, thereby effectively preventing vibrations from being transmitted to underground structures through the continuous partition walls. Effect of the Invention

[0024] As can be understood from the above explanation, the resin foam block and vibration reduction structure of the present invention can provide a resin foam block that can effectively reduce vibrations over a wide frequency range from low to high frequencies, and can provide a vibration reduction structure with excellent vibration reduction properties while eliminating the need for large-scale construction. [Brief description of the drawings]

[0025] [Figure 1] FIG. 2 is a perspective view of an example of a resin foam block according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of another example of a resin foam block according to the embodiment. [Diagram 3] 3 is a perspective view of the resin foam block shown in FIG. 2 in which rigidity-reducing voids are filled with soil. FIG. [Figure 4] 1 is a plan view of an example of a vibration reduction structure according to an embodiment; [Diagram 5] 5 is a view taken along the arrows VV in FIG. 4, and is a vertical cross-sectional view of an example of a vibration reducing structure according to an embodiment. [Figure 6] 13 is a perspective view showing a state in which the partition walls of the resin foam blocks arranged side by side are shifted. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Hereinafter, a resin foam block and a vibration reducing structure according to an embodiment will be described with reference to the accompanying drawings. In this specification and the drawings, substantially identical components are designated by the same reference numerals to avoid redundant description.

[0027] [Resin foam block and vibration reduction structure according to the embodiment] An example of a resin foam block and a vibration reduction structure according to the embodiment will be described with reference to Fig. 1 to Fig. 6. Here, Fig. 1 and Fig. 2 are perspective views of an example of a resin foam block according to the embodiment, and Fig. 3 is a perspective view of a form in which the rigidity reducing voids of the resin foam block shown in Fig. 2 are filled with soil. Fig. 4 is a plan view of an example of a vibration reduction structure according to the embodiment, and Fig. 5 is a view taken along the arrows VV in Fig. 4, which is a vertical cross-sectional view of an example of a vibration reduction structure according to the embodiment.

[0028] Resin foam block 10 shown in FIG. 1 has rectangular parallelepiped resin foam body 11, which has multiple side surfaces 12 (four in the illustrated example), a top surface 13, and a bottom surface .

[0029] Here, the material forming the resin foam body 11 can be expanded polystyrene (EPS), and more specifically, any one of polyurethane (PUR)-based foamed resin, polystyrene (PS)-based foamed resin, polyolefin-based foamed resin (PE: polyethylene, PP: polypropylene, EVA: ethylene vinyl acetate copolymer resin, etc.) can be used.

[0030] The resin foam body 11 has multiple (three in the illustrated example) rigidity-reducing voids 15 in the form of through holes that penetrate the resin foam body 11 and face the top end surface 13 and the bottom end surface 14, and partitions 17 are provided between adjacent rigidity-reducing voids 15.

[0031] In this manner, one or, as in the illustrated example, a plurality of rigidity-reducing voids 15 are provided in the resin foam body 11 to form the resin foam block 10. Here, in the illustrated example, the rigidity-reducing voids 15 are through-holes, but the rigidity-reducing voids may be, for example, spherical voids located inside the resin foam body 11.

[0032] Although the resin foam body 11 is a block having a relatively high rigidity, the rigidity of the resin foam body 11 is reduced by providing a predetermined number of rigidity-reducing voids 15 having a predetermined dimension.

[0033] Conventional EPS blocks have vibration-reducing effects in high-frequency bands, for example, 10 Hz or higher, but cannot be expected to have vibration-reducing effects in low-frequency bands of a few Hz or less. In contrast, the resin foam block 10 shown in the figure has a certain rigidity and can reduce vibrations in a wide range of frequencies from low to high. The resin foam block 10 is inherently lightweight, has resistance to compression, water resistance, weather resistance, and is self-supporting, making it an excellent block for installation underground.

[0034] 2 is a resin foam unit in which a resin foam plate 20 is fixed to the top surface 13 and the bottom surface 14 of a resin foam body 11. Here, the resin foam plate 20 is fixed to the top surface 13 etc. by adhesive.

[0035] Since the resin foam block 30 is installed underground, the resin foam board 20 is fixed to the top surface 13 and bottom surface 14 of the resin foam body 11 to block the rigidity-reducing void 15, thereby preventing soil from entering the rigidity-reducing void 15.

[0036] On the other hand, the resin foam block 40 shown in FIG. 3 is a resin foam unit in which the rigidity reducing gap 15 is filled with soil 18 and closed with a resin foam plate 20.

[0037] This resin foam unit 40 is installed beneath an underground structure and used as a component supporting the load of the underground structure, thereby providing stable load support for the underground structure in addition to vibration reduction over a wide frequency range due to the rigidity-reducing void 15.

[0038] Next, with reference to Figs. 4 to 6, an example of a vibration reducing structure in which the resin foam blocks 30, 40 shown in Figs. 2 and 3 are disposed at appropriate positions will be described.

[0039] 4 shows that a foundation 50 (an example of an underground structure) is located to the side of a road, which is a vibration source S, and has a continuous footing 55 that is rectangular in plan view and a bottom plate 51 made of reinforced concrete that is disposed inside the continuous footing 55. Since a building framework will be placed on the continuous footing 55, a large load will act on the continuous footing 55. Note that, for ease of explanation, the illustrated example shows a foundation that is rectangular in plan view as an underground structure, but underground structures that form vibration reduction structures include structures of various shapes.

[0040] As shown in FIG. 4, a plurality of resin foam blocks 30 are provided on the sides of a side surface 50a of a base 50 that is rectangular in plan view and faces the vibration source.

[0041] As shown in the illustrated example, since a vehicle C (the actual vibration source, see FIG. 5) moves along a road S, vibrations from the road S can propagate not only in the X1 direction as shown in the illustrated example to the side 50a facing the vibration source, which faces the road S, but also diagonally in the X2 direction.

[0042] For this reason, in addition to placing multiple resin foam blocks 30 only on the side 50a facing the vibration source as in the illustrated example, multiple resin foam blocks 30 may also be placed on a pair of side surfaces 50b that may face the vibration source.

[0043] Furthermore, if there is another vibration source (not shown) near the side 50c on the opposite side of the road S that does not face the vibration source, or if there is a possibility that a separate vibration source will be installed in the future, multiple resin foam blocks 30 may also be installed on the side 50c that does not face the vibration source, and therefore multiple resin foam blocks 30 may be installed around the entire circumference of the foundation 50.

[0044] As shown in Figure 4, multiple resin foam blocks 30 are installed on the side 50a of the foundation 50 facing the vibration source. In addition, as shown in Figure 5, multiple resin foam blocks 40 with soil 18 filled in the rigidity-reducing voids 15 are installed below the slab foundation 55, and multiple resin foam blocks 30 are installed below the bottom plate 51, which is not subjected to a large load compared to the slab foundation 55, thereby forming a vibration reduction structure 60.

[0045] 5, the road S has a layered structure of a roadbed S1, a roadbed S2, and a road body S3, and traffic vibrations (an example of environmental vibrations) generated when a vehicle C travels on the road S may propagate through the ground G and be input in the X1 direction to the foundation 50. In contrast, in the vibration reduction structure 60, a plurality of resin foam blocks 30 are installed side by side on at least the side surface 50a of the foundation 50 facing the vibration source, thereby effectively reducing the propagation of vibration to the foundation 50.

[0046] Here, as shown in FIG. 6, among the multiple resin foam blocks 30 arranged side by side on side surface 50a facing the vibration source, adjacent resin foam blocks 30 are arranged side by side with their partition walls 17 misaligned.

[0047] In Fig. 6, two resin foam blocks 30 are used to simulate one row of units, and three rows of units are shown arranged side by side. As shown in Fig. 6, by arranging the center second row unit slightly offset, the partition walls 17 of the first and third row units and the partition wall 17 of the second row unit between them are not continuous (the second row unit has a rigidity reducing gap 15 on line L instead of a partition wall 17).

[0048] In this manner, since the partition walls 17 in each row are not continuous, it is possible to prevent vibrations from the vibration source from being transmitted to the foundation via a plurality of continuous partition walls 17 .

[0049] Furthermore, in the vibration reduction structure 60, a plurality of resin foam blocks 40 with soil 18 filled in the rigidity-reducing voids 15 are installed below the slab foundation 55, where large loads may act, so that in addition to the vibration reduction properties over a wide frequency range provided by the rigidity-reducing voids 15, the slab foundation 55 is able to provide stable load support.

[0050] In addition, the configurations and the like of the above-mentioned embodiment may be combined with other components to form other embodiments, and the present invention is not limited to the configurations shown here. In this respect, the present invention can be modified within the scope of the gist of the present invention, and can be appropriately determined according to the application form. [Explanation of symbols]

[0051] 10: Resin foam block 11: Resin foam body 12: Side 13: Top surface 14: Bottom end surface 15: Gap for reducing rigidity 17: Bulkhead 18:Sat 20: Resin foam board 30, 40: Resin foam unit (resin foam block) 50: Underground structure (foundation) 51: Bottom plate 55:Slab foundation 50a: Side facing the vibration source 50b: Side likely to face vibration source 50c: Side not facing the vibration source 60: Vibration reduction structure S: Vibration source (road) C: Vibration source (vehicle) S1: Roadbed S2: Roadbed S3: Road body G: Underground

Claims

1. A resin foam block that is installed underground and reduces vibrations propagating underground, A resin foam body having a rectangular parallelepiped or approximately rectangular parallelepiped shape, A resin foam block, characterized in that the resin foam body is provided with rigidity-reducing voids.

2. The resin foam body has a plurality of side surfaces, a top surface, and a bottom surface, The rigidity reducing void penetrates the resin foam body and faces the top end surface and the bottom end surface, 2. The resin foam block according to claim 1, wherein a resin foam plate is fixed to each of the top end surface and the bottom end surface to close the rigidity reducing gap.

3. 3. A vibration reducing structure, comprising a plurality of the resin foam blocks according to claim 1 or 2 disposed on at least a side of an underground structure facing a vibration source.

4. A plurality of the resin foam blocks are disposed below an underground structure, and the rigidity reducing voids of the resin foam blocks are filled with soil; 4. The vibration reduction structure according to claim 3, wherein a plurality of the resin foam blocks are disposed on sides of the underground structure.

5. a plurality of the rigidity-reducing voids are provided in the resin foam body, and partition walls are provided between adjacent rigidity-reducing voids; 5. The vibration reducing structure according to claim 4, wherein the plurality of resin foam blocks are arranged side by side with the partition walls offset from one another.

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