Balusters and lattice-shaped structure

Abstract

To provide balusters which can reduce wind noise regardless of the direction of wind passing through a lattice-shaped structure, and a lattice-shaped structure provided with balusters.SOLUTION: Balusters 16 are arranged along the depth direction of a vertical lattice handrail 10. Respective upper ends 18a thereof are fixed to an upper rail 14, and lower ends 18b thereof are formed from two hollow members 18 fixed to a lower rail 14. The two hollow members 18 are arranged so as to be contacted each other on their respective opposing faces.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention is directed to reducing the volume of structure-borne sound (hereinafter referred to as wind noise) emitted by lattice structures consisting of handrails installed on windows, verandas, balconies, rooftops, emergency stairs, etc. of buildings, or fences installed on the boundaries of land, houses, etc., when they are hit by wind. [Background technology]

[0002] The above-mentioned lattice structure has a plurality of balusters that are arranged at intervals and extend linearly vertically, horizontally or diagonally. Wind noise is generated by a resonance phenomenon (vortex induced vibration) that occurs when the predominant frequency of Karman vortices that are generated when wind blows through between the balusters of the lattice structure matches the natural frequency of the balusters, or when the predominant frequency of the Karman vortices is close to the natural frequency of the balusters.

[0003] As a technique for reducing wind noise in a vertical lattice handrail, which is one type of lattice structure, Patent Document 1 discloses a wind noise reduction structure that includes a plate member that contacts the surface of the balusters. In this wind noise reduction structure, friction occurs between the balusters, which vibrate due to wind pressure, and the plate member, reducing the vibration of the balusters and therefore the wind noise. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2022-154394 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the technology of Patent Document 1 described above, when the side of the balusters to which the plate members are attached faces upwind, the plate members are pressed against the balusters by wind pressure, which tends to generate friction between the balusters and the plate members, making it easier to reduce wind noise.

[0006] In contrast, when the side of the balusters to which the plate members are attached faces downwind, pressure is applied to the plate members in a direction away from the balusters. As a result, friction between the balusters and the plate members becomes less likely to occur as the plate members move away from the balusters, making it difficult to reduce wind noise. Therefore, there has been a demand for technology that can reduce wind noise regardless of the direction of the wind passing through a lattice structure.

[0007] The present invention has been made in consideration of the above, and aims to provide a balusters that can reduce wind noise regardless of the direction of the wind passing through the lattice structure, and a lattice structure equipped with balusters. [Means for solving the problem]

[0008] In order to achieve the above-mentioned objective, the handrail of the present invention is a handrail used in a lattice structure consisting of a handrail or fence having a pair of bars, and is formed by a plurality of hollow members arranged along the depth direction of the lattice structure, each having one end fixed to one of the pair of bars and the other end fixed to the other bar, and the plurality of hollow members are arranged so that two adjacent hollow members are in contact with each other on their respective opposing surfaces.

[0009] The lattice structure of the present invention is a lattice structure consisting of a handrail or fence having a pair of rails and a plurality of balusters, each of which is made of the above-mentioned balusters of the present invention. Effect of the Invention

[0010] According to the present invention, it is possible to provide a balusters that can reduce wind noise regardless of the direction of wind passing through the lattice structure, and a lattice structure equipped with balusters. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a perspective view of a vertical lattice handrail, which is one example of a lattice structure according to the present invention. [Diagram 2] FIG. 2 is a partially enlarged view showing a part of FIG. [Diagram 3]FIG. [Figure 4] FIG. 13 is a diagram showing the results of a wind tunnel experiment. [Diagram 5] FIG. 13 is a diagram showing the results of a wind tunnel experiment. [Figure 6] FIG. 13 is a diagram showing the results of a wind tunnel experiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present invention is directed to reducing wind noise from lattice structures consisting of handrails (vertical lattice handrails, horizontal lattice handrails, diagonal lattice handrails, etc.) installed on windows, verandas, balconies, rooftops, emergency stairs, etc. of buildings, or fences installed on the boundaries of land, houses, etc.

[0013] As shown in FIG. 1, a vertical lattice handrail 10 , which is an example of a lattice structure to which the present invention is applied, comprises a pair of posts 12 , a pair of crosspieces 14 , and a plurality of balusters 16 .

[0014] In the following explanation, the vertical direction (up-down direction) of the vertical lattice handrail 10 is the direction perpendicular to the installation surface of the vertical lattice handrail 10. The depth direction of the vertical lattice handrail 10 is the direction perpendicular to the vertical direction and extends from the front side to the back side of the vertical lattice handrail 10. The horizontal direction (left-right direction) of the vertical lattice handrail 10 is the direction perpendicular to the vertical and depth directions. The vertical direction is parallel to the vertical direction, and the depth and horizontal directions are parallel to the horizontal direction.

[0015] The pair of support columns 12 are spaced apart from each other in the horizontal direction. The support columns 12 extend in the vertical direction. The support columns 12 are made of, for example, an extruded aluminum material.

[0016] The pair of crosspieces 14 are fixed to both of the support columns 12 and are spaced apart from each other in the vertical direction. The crosspieces 14 extend in the horizontal direction. The crosspieces 14 are made of, for example, an extruded aluminum material.

[0017] The multiple balusters 16 are arranged at intervals in the horizontal direction between both posts 12. The balusters 16 extend in the vertical direction.

[0018] As shown in Figures 2 and 3, the handrail 16 is formed of two hollow members 18 arranged along the depth direction. The hollow members 18 have a rectangular cross-sectional shape. The hollow members 18 extend in the vertical direction. The two hollow members 18 are formed to have the same shape. The hollow members 18 are made of, for example, an extruded aluminum material.

[0019] The hollow member 18 has an upper end 18a (corresponding to one end or the other end) and a lower end 18b (corresponding to the other end or one end) that face each other. The upper end 18a of the hollow member 18 is fixed to the upper crosspiece 14 (corresponding to one crosspiece or the other crosspiece), and the lower end 18b is fixed to the lower crosspiece 14 (corresponding to the other crosspiece or one of the crosspieces).

[0020] The hollow member 18 has a pair of outer wall surfaces (outer side surfaces) 18c facing each other in the depth direction and a pair of outer wall surfaces 18d facing each other in the lateral direction. The outer wall surfaces 18c, 18d are elongated rectangular flat surfaces extending in the vertical direction, which is the extension direction of the hollow member 18.

[0021] Of the two hollow members 18 of the balusters 16, the outer wall surface 18c on the rear side of the front-side hollow member 18 and the outer wall surface 18c on the front side of the rear-side hollow member 18 are in contact with each other over their entire surfaces. That is, the two hollow members 18 of the balusters 16 are arranged so that their outer wall surfaces 18c, which are the opposing surfaces of each, are in contact with each other. The two hollow members 18 may be fixed together with screws or the like.

[0022] Moreover, the hollow member 18 has a pair of inner wall surfaces (outer side surfaces) 18e facing each other in the depth direction, and a pair of inner wall surfaces 18f facing each other in the lateral direction.

[0023] Screw holes 18g are formed in each of the pair of inner wall surfaces 18f. The screw holes 18g are fastening holes for screws for fixing the upper end 18a of the hollow member 18 to the upper crosspiece 14 and the lower end 18b to the lower crosspiece 14. The screw holes 18g may be formed in the inner wall surface 18e.

[0024] Next, the function of the handrail 16 will be described.

[0025] When the vertical lattice handrail 10, which is equipped with multiple balusters 16, is exposed to wind, different wind pressures act on the hollow members 18 on the windward side and the hollow members 18 on the leeward side of the balusters 16. As a result, vibrations with different phases occur in the two hollow members 18 of the balusters 16. This phase difference causes friction between the outer wall surface 18c on the back side of the hollow member 18 on the front side and the outer wall surface 18c on the front side of the hollow member 18 on the back side.

[0026] This friction acts as a force that tries to stop the vibration through frictional damping (energy loss due to friction when considered in terms of energy balance), and increases the damping capacity of the balusters 16. Therefore, in the balusters 16, friction occurs between the mutually contacting outer wall surfaces 18c of the two hollow members 18, thereby reducing vibration and the associated wind noise more than in a balusters made of a single hollow member with the same outer diameter dimensions as the balusters 16.

[0027] The wind tunnel experiments carried out to verify this will be described below.

[0028] In this wind tunnel experiment, a balusters 16 was used, which was formed by arranging two aluminum hollow members 18 in the depth direction, each having a width (horizontal width), depth, thickness and length of 20 mm, 20 mm, 1.1 mm and 1000 mm, respectively. The balusters 16 used included one in which the two hollow members 18 were not fixed to each other, and one in which the two hollow members 18 were fixed to each other with screws at the midpoint in the vertical direction.

[0029] As a comparative example, a baluster made of an aluminum hollow member with a width (horizontal width), depth, thickness and length of 20 mm, 40 mm, 1.1 mm and 1000 mm, respectively, was used. The baluster of this comparative example is made of a single hollow member with the same outer diameter as the baluster 16 made of the above-mentioned two hollow members 18. Generally, for a lattice structure such as the vertical lattice handrail 10, a baluster made of a single hollow member such as the baluster of this comparative example is used.

[0030] In this wind tunnel experiment, wind with a speed of 3 to 20 m / s was blown in the depth direction onto each of the balusters 16 in which the two hollow members 18 were not fixed together as described above, the balusters 16 in which the two hollow members 18 were fixed together with screws, and the balusters of the comparative example. Then, the A-weighted sound pressure level, the X-direction (direction perpendicular to the direction in which the wind blows through) vibration acceleration level, and the Y-direction (direction in which the wind blows through) vibration acceleration level were measured.

[0031] The measurement results of the A-weighted sound pressure level, X-direction vibration acceleration level, and Y-direction vibration acceleration level in the wind tunnel experiment are shown in Figures 4, 5, and 6, respectively. In Figures 4 to 6, the measurement results of the balusters of the comparative example are shown as "without measures." In addition, the measurement results of the balusters 16 in which the two hollow members 18 are not fixed together are shown as "with measures," and the measurement results of the balusters 16 in which the two hollow members 18 are fixed together with screws are shown as "with measures (screw fastening)."

[0032] As shown in Figs. 4 to 6, in the handrail 16 formed from two hollow members 18 ("with measures" and "with measures (screw fastening)"), the A-weighted sound pressure level, X-direction vibration acceleration level, and Y-direction vibration acceleration level were reduced compared to the comparative example ("without measures"), confirming the effect of reducing wind noise.

[0033] As described above, the handrail 16 is formed by two hollow members 18 arranged along the depth direction so that their opposing outer wall surfaces 18c are in contact with each other, and each of their upper ends 18a is fixed to the upper rail 14 and each of their lower ends 18b is fixed to the lower rail 14.

[0034] Because the balusters 16 are thus formed from two hollow members 18 that contact each other at their outer wall surfaces 18c, when vibrations occur in the balusters 16 due to exposure to wind, the two hollow members 18 generate vibrations that are out of phase with each other as described above, causing friction between the two hollow members 18. Then, due to frictional damping caused by this friction, the vibrations and the associated wind noise are reduced more than in a balusters made of a single hollow member that has the same outer diameter as the balusters 16.

[0035] In addition, because the two hollow members 18 are fixed to a pair of bars 14, the hollow member 18 on the leeward side is prevented from separating from the hollow member 18 on the windward side, regardless of whether the front side or the back side of the vertical lattice handrail 10 is the windward side. For this reason, a frictional force can be generated between the two hollow members 18, regardless of the direction of the wind passing through the vertical lattice handrail 10.

[0036] Therefore, the handrail 16 can reduce wind noise regardless of the direction of the wind passing through the vertical lattice handrail 10.

[0037] In the above embodiment, the cross-sectional shape of the hollow member 18 is rectangular, but it is not limited thereto and may be another polygon such as a triangle or a cross-sectional shape including a curved portion. Also, for example, one of the two hollow members may have a recess and the other hollow member may have a protrusion that fits into the recess of the one hollow member, and the two hollow members may be arranged so that the recess and the protrusion are in contact with each other on their respective opposing surfaces to form a balustrade.

[0038] In the above-described embodiment, the two hollow members 18 are in contact with each other at the flat outer wall surface 18c. However, this is not limiting, and for example, the two hollow members may be opposed to each other, each having a convex curved surface on one side in the depth direction, and may be in contact with each other at the curved surfaces.

[0039] Also, in the embodiment described above, the balusters 16 are formed from two hollow members 18. However, this is not limited thereto, and the balusters 16 may be formed from a plurality of hollow members arranged along the depth direction, and the plurality of hollow members may be arranged such that two adjacent hollow members are in contact with each other on their respective opposing surfaces.

[0040] In the above-described embodiment, the balusters 16 are formed of two hollow members 18 of the same shape. However, the two hollow members 18 forming the balusters 16 may have different shapes. In addition, when the balusters 16 are formed of three or more hollow members, all of the hollow members may have the same shape, or may include a hollow member of a different shape from the other hollow members. For example, two adjacent hollow members in a portion of the plurality of hollow members may be such that one of the hollow members has the above-described recess and the other hollow member has the above-described protrusion, and the remaining hollow members of the plurality of hollow members have a different shape.

[0041] The present invention is not limited to the above-described embodiment, and the components can be modified and embodied in the implementation stage without departing from the gist of the invention. In addition, various inventions can be formed by appropriately combining the multiple components disclosed in the above-described embodiment. For example, some components may be deleted from all the components shown in the embodiment. [Explanation of symbols]

[0042] 10 Vertical lattice handrail 12 pillars 14 Crossing 16 Baluster 18 Hollow members 18a top end 18b Bottom edge 18c, 18d Exterior wall

Claims

1. A balusters used in a lattice structure consisting of a handrail or fence having a pair of rails, the plurality of hollow members are arranged along a depth direction of the lattice structure, one end of each of the hollow members is fixed to one of the pair of beams, and the other end of each of the hollow members is fixed to the other beam, The plurality of hollow members are arranged such that two adjacent hollow members are in contact with each other on their respective opposing surfaces.

2. The balustrade of claim 1 , wherein the hollow member has a rectangular cross-sectional shape.

3. one of at least two adjacent hollow members of the plurality of hollow members has a recess and the other hollow member has a protrusion that fits into the recess, The handrail according to claim 1 , wherein the one hollow member and the other hollow member are arranged such that the recessed portion and the protruding portion are in contact with each other on their respective surfaces facing each other.

4. A lattice-like structure consisting of a handrail or fence having a pair of rails and a plurality of balusters, A lattice structure, each of which is made of a balustrade according to any one of claims 1 to 3.

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