JP2008101384A - Columnar body vibration control structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a columnar body vibration control structure which achieves vibration control effect against external vibration of a high frequency component and a low frequency component, and soundproofing effect against noise. <P>SOLUTION: According to the columnar body vibration control structure, a first hollow member 7 is arranged on a pedestal plate 5 set at a setting section, via a second damping member 6, and a second hollow member 16 is arranged on an upper flange portion 7b of the first hollow member 7, via a first damping member 12, followed by fixing a grip member 13 to which a columnar body 2 is fastened, to the second hollow member 16. The columnar body 2 has its lower end 2a inserted into the first and second hollow members 7, 16, and fixed to the same via a foamed elastic body 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vibration damping structure for a columnar body that is supported by a lower part and is cantilevered or gate-shaped with an upper part being opened and is installed to stand upright from an installation surface.

  Conventionally, the lower end portion of a columnar structure such as a TV antenna supporting steel pipe or a lightning rod supporting column attached to a building or a road sign tower, electric lamp, street lamp, electric pole, overhead line supporting column installed on a road or railway overhead line is fixed. A cantilever or portal columnar body is installed.

  Since antenna devices and lightning rods used for receiving television broadcasts used in buildings are installed at high places, the antenna, antenna support steel pipe, and lightning rods vibrate due to wind. In addition, road sign towers, lamps, street lamps, utility poles, overhead wire support pillars and the like installed on roads and railway overhead lines vibrate when the vehicle travels or vibrations caused by wind are transmitted to the columnar bodies.

  The vibration is transmitted to the building structure because the antenna, antenna support steel pipe, lightning rod, etc. attached to the building are damaged due to material fatigue due to repeated vibration caused by the wind, and are also tightly connected to the building structure. It becomes a factor that generates noise in the dwelling unit of the building, and gives anxiety to residents. Also, columnar bodies installed on roads and railway overhead lines may cause fatigue failure due to repeated vibration.

  Conventionally, various damping devices have been proposed to control the vibration. For example, in Japanese Patent Laid-Open No. 2002-188321 (Patent Document 1), a mounting member that supports a support column is fixed on a base of a steel tower with a high-damping rubber support interposed therebetween, and the lower end portion of the tower body is a rooftop of a building. A vibration damping structure supported by a structure that can be regarded as a pin or a pin roller has been proposed.

  Japanese Patent Laid-Open No. 10-096280 (Patent Document 2) and Japanese Patent Laid-Open No. 10-12179 (Patent Document 3) have proposed that a liquid, a granular material, and a sphere are installed on a columnar body. JP 2003-328590 A (Patent Document 4) proposes a cable with an elastic body installed in a hollow portion of a columnar body.

  Japanese Utility Model Laid-Open No. 02-006835 (Patent Document 5) controls vibration by coupling a container in which a fluid substance such as silicon oil, water, and sand is sealed inside the columnar body. Japanese Laid-Open Patent Publication No. 2005-172210 (Patent Document 6) proposes a columnar body hollow portion provided with a weight suspended through a high damping rubber. .

Japanese Patent Laying-Open No. 2002-188321 (FIG. 2) JP-A-10-096280 Japanese Patent Application Laid-Open No. 10-121779 JP 2003-328590 A Japanese Utility Model Publication No. 02-006835 JP 2005-172210 A

  However, in the technique of the above-mentioned Patent Document 1, although a high-damping rubber support is mounted on a base of a steel tower and a support member for supporting a support is fixed, vibrations of high-frequency components can be damped by the high-damping rubber support. There was a problem that the vibration of the low frequency component remained.

  Further, in the techniques of Patent Documents 2 and 3, it is difficult to install and maintain the liquid, the granular body, and the sphere at the high place above the columnar body.

  In the techniques of Patent Documents 4 and 5, a cable with an elastic body is installed in the hollow portion of the columnar body, or a container enclosing a fluid substance such as silicon oil, water, and sand is coupled to the columnar body. In order to control the vibration, the internal installation must be changed according to the size and weight of the columnar body, and there is a problem that the design value must be changed for each installation.

  Moreover, in the technique of patent document 6, since the weight suspended through the high damping rubber is installed in the hollow part of the columnar body, the collision sound of the weight is generated, and the inside may be damaged by the collision of the weight.

  In addition, the techniques of Patent Documents 2 to 6 are basically applicable to low frequencies of 10 Hz or less, but it is difficult to obtain an effect in a frequency band of 20 Hz or more, which is a sound region. there were.

  The present invention solves the above-mentioned problems, and its object is to provide a columnar body damping structure capable of obtaining a damping effect and a soundproofing effect against external vibration and noise of high-frequency components and low-frequency components. To do.

  In order to achieve the above object, the structure of the vibration damping structure for a columnar body according to the present invention includes a columnar body, a columnar body supporting member that holds and supports the lower side surface of the columnar body, and a lower surface of the columnar body supporting member. A first attenuating member mounted on the lower surface of the first attenuating member; a second attenuating member mounted on the lower surface of the intermediate member; and a second attenuating member A leg member located on a lower surface and connected to a building frame, wherein the first damping member is fixed so as to maintain a non-contact state with respect to the columnar body support member and the intermediate member, The second damping member is press-fixed by a fixture that connects the intermediate member and the leg member.

  According to the vibration damping structure for a columnar body according to the present invention, since the horizontal displacement between the columnar body supporting member and the intermediate member is large and only the first damping member is disposed at a high position, a large displacement at a low frequency can be obtained. Since the second damping member can be damped by using a fixture such as a bolt at a position where the horizontal displacement between the intermediate member and the leg member is small and low, the horizontal load applied to the columnar body can be reduced. It is possible to attenuate high-frequency micro-vibration while ensuring the reaction force against vibration, and to attenuate vibration over a wide range from low frequency to high frequency, and exhibit excellent effects against fatigue and sound generation due to repetition I can do it.

  An embodiment of a vibration damping structure for a columnar body according to the present invention will be specifically described with reference to the drawings. FIG. 1 is a perspective explanatory view showing a columnar body damping structure according to the present invention, FIG. 2 is a sectional explanatory view showing a columnar body damping structure according to the present invention, and FIG. 3 shows a configuration of a first hollow member. FIG. 4 is a diagram showing the configuration of the second hollow member of the columnar body support portion, FIG. 5 is a diagram showing the configuration of the gripping member of the columnar body support portion, and FIG. 6A is the configuration of the first damping member. FIG. 6B is a diagram showing the configuration of the base plate, FIG. 7 is a diagram showing the configuration of the foamed elastic body, FIG. 8 is a diagram showing the configuration of the second damping member, and FIG. 9 is an equivalent viscosity damping It is a figure explaining the constant Heq.

  1 and 2, reference numeral 1 denotes a vibration damping structure for a columnar body 2 that is supported at the lower part and is cantilevered or gate-shaped with the upper part open, and is installed upright from the installation surface. Specific examples of the columnar body 2 include a television antenna support column and a lightning rod support column associated with a building.

  For example, when the columnar body 2 is installed on a flat roof of a building, as shown in FIG. 1, the installation section is transferred to two orthogonal beam members 3 of a steel frame, and each beam of the beam members 3 is provided. It is comprised by the leg member 4 connected with the corner | angular part of the L-shaped installation member 17 joined to 3a. The columnar leg member 4 has a screw hole 4a formed on the top surface, and is inserted into a through hole formed in an ALC (lightweight cellular concrete) floor panel 18 on the roof and protrudes from the roof waterproof sheet surface.

  A floor panel support plate 4b arranged at the same height as the surface of the upper flange 3b of the beam member 3 is provided at an intermediate portion of the leg member 4 connected to the building frame, and a through hole serving as a defective portion is drilled. The ALC floor panel 18 is placed on the upper flange 3b of the beam member 3 and the floor panel support plate 4b and supported stably. Further, a fire-beam-shaped reinforcing bar 19 is stretched over and fixed to the lower flange 3c of the beam member 3 in two orthogonal directions.

  A rectangular base plate 5 is placed on the top surface of the leg member 4, a bolt 8 is inserted into a through hole 5 b formed in the base plate 5, and screwed into the screw hole 4 a of the leg member 4. A base plate 5 is fixed to the leg member 4.

  A first hollow member 7 serving as an intermediate member is connected to the base plate 5 with a second damping member 6 interposed therebetween. As shown in FIG. 3, the first hollow member 7 is provided with upper and lower flange portions 7b and 7c at both ends of the cylindrical portion 7a. The lower flange portion 7c is configured in a rectangular shape that is substantially the same shape as the outer shape of the pedestal plate 5, and a second damping member 6 that is configured in a rectangular shape that is approximately the same shape as the outer shape of the pedestal plate 5 on the pedestal plate 5 is placed thereon. Then, the lower flange portion 7c is placed and stacked on the second damping member 6, and the through hole 5a provided in the base plate 5 and the through hole 6a provided in the second damping member 6 are The first hollow member 7 is connected to the pedestal plate 5 by inserting a bolt 8 through a through hole 7c1 provided in the flange portion 7c and fastening a nut 9 with a predetermined torque. In FIG. 3, reference numeral 7 d denotes a water drain groove for discharging water that has entered the hollow member 7.

  In the present embodiment, the first hollow member 7 serving as an intermediate member is mounted on the lower surface of the first attenuation member 12, and the leg member 4 is located on the lower surface of the second attenuation member 6.

  As shown in FIG. 6, the second damping member 6 mounted on the lower surface of the first hollow member 7 serving as an intermediate member has an outer diameter of the head of the bolt 8 with the pedestal plate 5 fixed to the leg member 4. A through hole 6b having a larger diameter is formed, and when the lower flange portion 7c of the first hollow member 7 is connected to the pedestal plate 5 with the second damping member 6 interposed therebetween, the head of the bolt 8 is formed. Is prevented from interfering with the second damping member 6. The thickness of the second damping member 6 is set to be greater than the height of the head of the bolt 8, and the base plate 5 and the second damping member 6 are not interfered with by the head of the bolt 8. And the lower flange portion 7c are brought into close contact with each other.

  In this way, the second damping member 6 is pressure-fixed by the bolts 8 and nuts 9 serving as fixtures that connect the first hollow member 7 serving as an intermediate member and the leg member 4.

  The second damping member 6 is not particularly limited as long as it has a damping performance against vibration energy, but an elastic material is preferably used. For example, norbornene polymer natural rubber, styrene butadiene rubber, isoprene rubber, butadiene rubber, chloroprene rubber, nitrile tolyl rubber, ethylene-propylene copolymer rubber, butyl rubber, IIR (isobutylene isoprene rubber) rubber (butyl rubber) and EPDM (Ethylene) Propylene Diene Methylene Linkage (ethylene-propylene-diene terpolymer) rubber or the like can be used alone or in combination as a composition having a predetermined damping performance.

  A foamed elastic body 11 shown in FIG. 7 is fitted on the lower flange portion 7 c inside the first hollow member 7, and a lower end portion 2 a of the columnar body 2 is inserted into a groove portion 11 a provided in the foamed elastic body 11. The lower end 2 a of the columnar body 2 is inserted and placed on the lower flange portion 7 c through the foamed elastic body 11. The foamed elastic body 11 is composed of a foamed viscoelastic body made of sponge rubber or the like having a sponge hardness (in accordance with JIS S 6050) of 40 or less.

  The foamed elastic body 11 is omitted, and the inner diameter of the cylindrical portion 7a of the first hollow member 7 is larger than the maximum amplitude of the lower end portion 2a of the columnar body 2 when the columnar body 2 is vibrated by an external force. The bottom end 2a of the columnar body 2 is inserted into the cylindrical portion 7a and the columnar body 2 is floated from the lower flange portion 7c, that is, the vertical load from the columnar body 2 will be described later. It may be fixed so as to be supported by the member 13.

  A gripping member 13 for fastening the columnar body 2 is connected to the circular upper flange portion 7b of the first hollow member 7 serving as an intermediate member with a first damping member 12 shown in FIG. 8 interposed therebetween. The first damping member 12 has 100 parts by weight to 150 parts by weight of silica added to 100 parts by weight of the base rubber having a “C (carbon) -C (carbon) bond” in the main chain. It is comprised by the high damping rubber which mix | blended 10 weight%-30 weight% of silane compounds.

  As shown in FIG. 8, the first damping member 12 is made of a disk-like viscoelastic body, and is provided with strip-shaped joining pieces 14 and 15 crossing a cross fixed on both surfaces thereof by an adhesive or the like. ing.

  One joining piece 14 is placed on the upper flange portion 7b of the first hollow member 7, and bolts are inserted into the through hole 7b1 provided in the upper flange portion 7b and the through hole 14a provided in the joining piece 14. 8 is inserted, and a nut 9 is screwed and fastened to the bolt 8 to be fixed.

  In the present embodiment, as shown in FIG. 3, a pair of through holes 7b1 are provided at positions that divide the circumference of the upper flange portion 7b into three equal parts, and as shown in FIG. Are arranged at positions shifted by 120 degrees.

  The number of the first damping members 12 arranged is not limited to three as in the present embodiment, and other plural sets of the first damping members 12 are provided so that the direction of the damping effect does not occur. You may arrange | position and the 1st damping member 12 comprised by cyclic | annular form, such as a ring shape, may be arrange | positioned on the upper flange part 7b. In this case, the first damping member 12 may be fixed to both surfaces of the upper flange portion 7b of the first hollow member 7 and the lower flange portion 16c of the second hollow member 16 with an adhesive or the like.

  The columnar body support member 22 that grips and supports the lower side surface of the columnar body 2 includes a second hollow member 16 shown in FIG. 4 and a gripping member 13 shown in FIG. The first damping member 12 is fixed so as to maintain a non-contact state with respect to the columnar body support member 22 and the first hollow member 7 serving as an intermediate member.

  As shown in FIG. 4, the second hollow member 16 includes a cylindrical portion 16a having an inner diameter through which the columnar body 2 is inserted, and upper and lower flange portions 16b and 16c provided at both ends of the cylindrical portion 16a. The lower flange portion 16c of the second hollow member 16 is disposed on the joining piece 15 joined to the other of the first damping members 12 mounted on the lower surface of the columnar body support member 22. The bolt 8 is inserted into the through hole 16c1 provided in the lower flange portion 16c and the through hole 15a provided in the joining piece 15, and the nut 9 is screwed and fastened to the bolt 8 to be fixed. .

  As shown in FIG. 5, the gripping member 13 is provided at a pair of semi-cylindrical portions 13a that are divided into two as a whole, flanges 13b provided on both sides thereof, and one end of the semi-cylindrical portion 13a. The inner surface side of the semi-cylindrical part 13a in a state where the columnar body 2 is inserted into the cylindrical part constituted by combining the pair of semi-cylindrical parts 13a. Is pressed against the circumferential surface of the columnar body 2 via a rubber pad 20 or the like, and a bolt 8 is inserted into a through hole 13b1 provided in the flange portion 13b. A nut 9 is screwed and fastened to the bolt 8 to be fixed. Is gripped by the gripping member 13.

  A lower flange portion 13c of the gripping member 13 is placed on the upper flange portion 16b of the second hollow member 16, and the through hole 13c1 provided in the lower flange portion 13c and the second hollow member 16 are A bolt 8 is inserted into a through hole 16b1 provided in the flange portion 16b, and a nut 9 is screwed and fastened to the bolt 8 to be fixed.

  As shown in FIG. 5, the through hole 13c1 provided in the lower flange portion 13c of the one gripping member 13 divided into two is formed with a long hole instead of a round hole, so that the outer diameter of the columnar body 2 is increased. In addition, the gripping member 13 can be securely fixed to the second hollow member 16. Further, as shown in FIG. 5, the spacing between the mutually facing flanges 13 b of the gripping member 13 that is divided into two parts is set to be different, whereby the gripping member 13 is matched to the outer diameter of the columnar body 2. Can be securely fixed to the columnar body 2.

  As described above, the columnar body support member 22 supports the columnar body 2 and transmits part or all of the load to the lower structure.

  According to the above configuration, when external force such as wind or external vibration is input to the columnar body 2 and vibration is generated in the columnar body 2, the vibration of the columnar body 2 is transmitted to the gripping member 13 and the second hollow member 16. With displacement. The first damping member 12 provided between the second hollow member 16 and the first hollow member 7 absorbs vibration and displacement transmitted from the columnar body 2 to the gripping member 13 and the second hollow member 16. However, it is not transmitted to the first hollow member 7.

  Further, vibration transmission from the columnar body 2 main body is prevented from being transmitted by installing it through the foamed elastic body 11 or floating the columnar body 2 main body so as to be freely movable. Further, for high-frequency vibration (fine vibration) without displacement, vibration energy of high-frequency vibration is absorbed by the second damping member 6 interposed between the base plate 5 and the lower flange portion 7c of the first hollow member 7. .

  In addition, the structure of the columnar body 2 itself that can be applied is not limited because it is a vibration-damping structure that fits outside and at the lower end of the columnar body 2, and maintenance is easy because it can be installed without working at a high place. Can also be made inexpensively.

  As an example of use of the present invention, it can be applied to a vibration control structure of a columnar body that is supported at the lower part and is open at the upper part and is installed upright from the installation surface, particularly a television attached to a building. Cantilever type or gate type with fixed lower end of pillar structure such as antenna support steel pipe, lightning rod support pillar, road sign tower, electric lamp, street light, electric pole, overhead wire support pillar installed on road or railway overhead line Widely applicable to columnar bodies.

It is an isometric view explanatory drawing which shows the damping structure of the columnar body which concerns on this invention. It is sectional explanatory drawing which shows the damping structure of the columnar body which concerns on this invention. It is a figure which shows the structure of a 1st hollow member. It is a figure which shows the structure of a 2nd hollow member. It is a figure which shows the structure of a fastening member. (A) is a figure which shows the structure of a 1st damping member, (b) is a figure which shows the structure of a base plate. It is a figure which shows the structure of a foaming elastic body. It is a figure which shows the structure of a 2nd attenuation member. It is a figure explaining the equivalent viscous damping constant Heq.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Damping structure 2 ... Columnar body 2a ... Lower end part 3 ... Beam 3a ... Web 3b ... Upper flange 3c ... Lower flange 4 ... Leg member 4a ... Screw hole 4b ... Floor panel support plate 5 ... Base plate 5a, 5b ... Through-hole 6 ... 2nd damping member 6a, 6b ... Through-hole 7 ... 1st hollow member 7a ... Cylindrical part 7b, 7c ... Vertical flange part
7b1, 7c1 ... Through hole 7d ... Drain groove 8 ... Bolt 9 ... Nut
10 ... Hysteresis curve
11 ... Foam elastic body
11a ... Groove
12 ... 1st damping member
13 ... Fastening member
13a ... Semi-cylindrical part
13b ... Buttocks
13c ... Lower flange
13c1 ... through hole
14,15 ... Joint piece
14a, 15a ... through hole
16 ... second hollow member
16a ... Cylindrical part
16b, 16c ... Vertical flange
16b1, 16c1 ... through hole
17… Installation material
18 ... ALC floor panel
19… Reinforcing plate
20 ... Rubber pad
22 ... Columnar support member

Claims (1)

A columnar body;
A columnar body supporting member that holds and supports the lower side surface of the columnar body;
A first damping member mounted on the lower surface of the columnar body support member;
An intermediate member mounted on the lower surface of the first damping member;
A second damping member mounted on the lower surface of the intermediate member;
A leg member located on the lower surface of the second damping member and connected to the building frame;
Have
The first damping member is fixed so as to maintain a non-contact state with respect to the columnar body support member and the intermediate member,
The columnar body damping structure, wherein the second damping member is press-fixed by a fixing member that connects the intermediate member and the leg member.

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