JP5436026B2 - Seismic isolation device plug and method of manufacturing the same - Google Patents

Description

  The present invention relates to a plug for a seismic isolation device, a manufacturing method thereof, and a seismic isolation device using the plug.

  2. Description of the Related Art Conventionally, seismic isolation devices in which soft plates having viscoelastic properties such as rubber and hard plates such as steel plates are alternately stacked are used as a support for the seismic isolation device. Among such seismic isolation devices, for example, there is one in which a hollow portion is formed at the center of a laminate made of a soft plate and a hard plate, and a plug for the seismic isolation device is press-fitted into the hollow portion.

  As the plug for the seismic isolation device, a plug made entirely of lead is often used, and when the laminated body undergoes shear deformation, the vibration isolating device plug plastically deforms to absorb vibration energy. . However, lead has a large environmental burden and a high cost for disposal. Therefore, an attempt has been made to develop a plug for a seismic isolation device having sufficient damping performance, displacement followability, etc., using an alternative material of lead.

  For example, in Patent Document 1, instead of a seismic isolation device plug made of lead, a powder material made of an elastomer composition and powder is enclosed in a hollow portion of a laminate, and the gap between the powders is made of the elastomer composition. A plug for a seismic isolation device has been proposed. Such a plug for a seismic isolation device has a relatively stable damping performance and displacement followability even when used for a long time, like a plug for a seismic isolation device made of lead. Examples of the elastomer composition include a rubber material, and examples of the powder include metals, hard resins, and hard fibers.

JP 2006-316990 A

  Although the seismic isolation device using the seismic isolation plug described in Patent Document 1 stably secures the damping characteristics and the displacement followability, the seismic isolation device is against the background of the recent increase in size and height of construction. Therefore, further improvement in the damping characteristics and displacement followability of the seismic isolation device is desired.

  An object of the present invention is to provide a plug for a seismic isolation device that exhibits sufficient damping performance and displacement followability, and a seismic isolation device using the plug for the seismic isolation device. Another object of the present invention is to provide a method by which the seismic isolation device plug can be easily manufactured.

The inventors of the present invention have sought to improve the performance of a plug comprising a molded body containing an elastomer composition and a powder, and as a result, the molded body has a lower thickness in the thickness direction. increasing distance from the center in a cross section direction Cartesian, it has been found that it tends to air content increases. Thus, it has been found that a molded body having a partially high air content does not exhibit sufficient damping performance and displacement followability when used as a plug for a seismic isolation device. On the other hand, it has also been found that a molded body molded at a high pressure does not exhibit sufficient damping performance and displacement followability because it is partially hard and lacks flexibility, although there is no portion with a high air content.

Based on the above knowledge, as a result of further intensive studies by the present inventors, the molded product containing the elastomer composition obtained by blending the elastomer component with the reinforcing filler and the powder, the thickness and the thickness by setting the ratio between the diameter of the cross section direction Cartesian to a predetermined range, book found that air is evenly reduced, can be provided seismic isolation system for a plug exhibit sufficient damping performance and displacement tracking property The invention has been completed.

  That is, the gist configuration of the present invention is as follows.

  (1) A plurality of plug materials containing an elastomer composition obtained by blending a reinforcing filler in an elastomer component and powder, and the plug material has a thickness h (mm) and a thickness A plug for a seismic isolation device, wherein a ratio h / D to a diameter D (mm) of a cross section perpendicular to the vertical direction satisfies 0.02 to 0.7.

  (2) A plug for a seismic isolation device containing an elastomer composition obtained by blending a reinforcing filler in an elastomer component and powder, and the thickness h (mm) is orthogonal to the thickness direction. A plug for a seismic isolation device, characterized in that a ratio h / D to a cross-sectional diameter D (mm) satisfies 0.02 to 0.7.

  (3) The plug for a seismic isolation device according to (1) or (2), wherein the thickness h is 5 mm or more.

  (4) By pressing an elastomer composition obtained by blending a reinforcing filler into an elastomer component and powder, a thickness h (mm) and a diameter D (mm) of a cross section perpendicular to the thickness direction ) And a plug material for a seismic isolation device in which a plug material satisfying a ratio h / D of 0.02 to 0.7 is molded and the plug materials are laminated.

  (5) By pressing an elastomer composition obtained by blending a reinforcing filler in an elastomer component and powder, a thickness h (mm) and a diameter D (mm) of a cross section perpendicular to the thickness direction And the ratio h / D to the manufacturing method of the plug for a seismic isolation device satisfying 0.02 to 0.7.

  (6) In the seismic isolation device having a laminate having a hollow portion extending in the laminating direction, in which rigid plates and elastic plates are alternately laminated, the hollow portions of the laminate (1) to (3) A seismic isolator characterized by press-fitting the plug for seismic isolator described in 1.

  According to the present invention, the ratio h / D between the thickness h (mm) of the plug material and the diameter D (mm) of the cross section perpendicular to the thickness direction is set within the range of 0.02 to 0.7. Since the air content is low, it is possible to provide a plug for a seismic isolation device that exhibits sufficient damping performance and displacement followability, and further a seismic isolation device using the plug. Furthermore, according to the manufacturing method of this invention, the said plug for seismic isolation devices can be manufactured easily.

It is a figure which shows the structure of one embodiment of the seismic isolation apparatus of this invention. It is a figure which shows one embodiment of the plug for seismic isolation apparatuses of this invention. It is a figure which shows the relationship between the shear distortion (gamma) and the shear stress (tau). It is a graph which shows the relationship between h / D of a plug material, and an air content rate. It is a graph which shows the relationship between a horizontal deformation displacement and a shear stress in the seismic isolation apparatus using the plug for seismic isolation apparatuses of this invention.

  Next, the seismic isolation device and the plug for the seismic isolation device of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing the structure of one embodiment of the seismic isolation device of the present invention, and FIG. 2 is a diagram showing one embodiment of the plug for the seismic isolation device of the present invention.

  A seismic isolation device 1 according to an embodiment of the present invention shown in FIG. 1 is a cylinder in which a rigid plate 2 having rigidity and an elastic plate 3 having elasticity are alternately stacked, and extends in the stacking direction (vertical direction). Laminate 4 having a hollow portion in the center, seismic isolation device plug 8 press-fitted into the hollow portion of laminate 4, and both ends (upper and lower ends) of laminate 4 and seismic isolation device plug 8 Further, the outer peripheral surface of the laminate 4 is covered with a covering material 7. When the seismic isolation device 1 receives a shearing force in the horizontal direction due to the vibration caused by the earthquake, the seismic isolation device plug 8 is sheared and deformed together with the laminate 4, effectively absorbing the vibration energy and absorbing the vibration. It can be quickly attenuated.

  Here, as shown in FIG. 2, the seismic isolation device plug 8 is formed by stacking a plurality of plug members 5, three plug members 5 in the illustrated example, and the thickness of each plug member is h (mm), It is important that the ratio h / D satisfies 0.02 to 0.7 when the diameter of the cross section perpendicular to the thickness direction is D (mm). Thus, by pre-molding plug materials that satisfy the above requirements and stacking them together to produce a plug for a seismic isolation device, variations in air content in the thickness direction and radial direction are alleviated. As a result, the air content rate is also lowered, so that a plug for a seismic isolation device having a low air content rate as a whole can be provided.

In the following, the experiments conducted to define the value of h / D within the above range and the results will be described in detail. First, for plugs having different air contents, the results of evaluation of the relationship between the shear strain γ and the shear stress τ are shown. From the graph of FIG. 3, in the state where the strain γ is 1.5 (150%) or more, In order to satisfy the target value of stress, τ = 80 kgf / cm ² or less, it can be seen that the air content needs to be 6% or less.

Next it was examined the relationship between the ratio h / D of the air content of the plug material, and the thickness h (mm) and said thickness direction and Cartesian cross-section of diameter D (mm), which are It has a proportional relationship as shown in FIG. 4, and it is found that the h / D value needs to be 0.7 or less in order to make the air content of the plug material of the present invention 6% or less. It was.

  Therefore, considering these results, the h / D value of the plug material should be 0.02 to 0.7 in order to give sufficient damping performance and displacement followability to the plug for a seismic isolation device of the present invention. is necessary.

  Here, when the value of h / D is less than 0.02, the plug material loses flexibility, and the workability of manufacturing the plug deteriorates. Therefore, the value of h / D of the plug material needs to be 0.02 or more. Moreover, when the dispersion | variation at the time of manufacture by factors other than an air content rate is considered, it is preferable that the air content rate of a plug material is 2.9-5%. Therefore, as can be seen from FIG. 4, the value of h / D is preferably 0.02 to 0.46.

  In FIG. 2, the seismic isolation device plug 8 is formed by laminating three plug members 5. However, the number of plug members laminated is not particularly limited as long as the h / D value of the plug material is within the specified range. Can be appropriately selected. Accordingly, if the h / D of the seismic isolation device plug is within a specified range, it can be used as a single seismic isolation device plug without being divided.

Further, the thickness h (mm) is not particularly limited as long as the value of h / D is within the specified range. For example, the thickness h (mm) may be different between stacked plugs. Furthermore, the shape of the cross section of the thickness direction and Cartesian, of a cross section perpendicular to the thickness direction diameter D (mm) is not particularly limited so long as it is within the scope of the above definition, for example, a positive 16 rectangular, regular octagon Preferred examples include regular polygons and circles, and the like, but circles are particularly preferred because there is no anisotropy against stress. That is, the plug material is preferably cylindrical.

  The thickness h is preferably 5 mm or more. This is because if h is less than 5 mm, the number of the plug materials to be stacked increases, so that the press-fitting of the plug material into the seismic isolation device becomes troublesome and the plug material is easily broken. Furthermore, it becomes difficult to mold the plug material uniformly. More preferably, the thickness h is 20 to 100 mm.

  As the elastomer component used in the elastomer composition, those exhibiting rubber elasticity at room temperature, for example, rubbers such as natural rubber and synthetic rubber, and thermoplastic elastomers can be used. Among these, natural rubber and synthetic rubber can be used. It is preferable to use a rubber such as Natural rubber and synthetic rubber-based polymers are viscoelastic and show some elasticity, but have great plasticity, can follow large deformations, and can re-aggregate in the same state again when returning to the origin after vibration. Further, when the elastomer component is rubber (that is, when the elastomer composition is a rubber composition), the damping performance of the seismic isolation device plug is improved and the durability is also improved.

  More specifically, the elastomer component includes natural rubber (NR), polyisoprene rubber (IR), polybutadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), ethylene-propylene rubber, nitrile. Rubber, butyl rubber, halogenated butyl rubber, acrylic rubber, polyurethane, silicone rubber, fluorinated rubber, polysulfide rubber, hyperon, ethylene vinyl acetate rubber, epichlorohydrin rubber, ethylene-methyl acrylate copolymer, styrene elastomer, urethane elastomer, polyolefin Based elastomers and the like. These elastomer components may be used alone or in a blend of two or more.

  The elastomer component is preferably at least partially, preferably all uncrosslinked, specifically unvulcanized. When the elastomer component is completely cross-linked, it deforms when subjected to large deformation, but the position of the powder cannot be changed during deformation, and it becomes impossible to follow the deformation at a certain limit point. The elastomer part is broken or tries to return to its original shape by the repulsive force of the crosslinked elastomer part. If the cross-linked elastomer part breaks, the damping performance plug will not return to its original shape even if the position of the base isolation device plug returns to the origin, and the damping performance will gradually decrease. When the repulsive force of the elastomer part works, the original damping performance cannot be exhibited.

  On the other hand, if the elastomer component is uncrosslinked, it is possible to follow the deformation, and when the plug for the seismic isolation device receives a history of large deformation and then returns to the origin, the plug for the seismic isolation device is used. Since hydrostatic pressure is applied to the whole, the seismic isolation device plug can return to its original shape, and as a result, the same performance as the initial stage can be maintained over a long period of time. In addition, when the number of cross-linking points is very small, or when only the surface of the plug material is cross-linked, after the plug for the seismic isolation device is deformed, it can return to the original shape. It refers to a state in which the crosslinking reaction has not yet been completely completed, and includes a partially crosslinked state.

  As the reinforcing filler, carbon black and silica are preferable, and carbon black is particularly preferable in that the effect of improving the viscosity of the elastomer composition by interaction with the elastomer component is great. Since carbon black and silica have a large effect of improving the viscosity of the elastomer composition by interaction with the elastomer component, the flow resistance of the plug material is increased, and as a result, the damping effect of the plug for the seismic isolation device is increased.

  Here, examples of the carbon black include SAF, ISAF, and HAF grades. Among these, fine particles such as SAF and ISAF grades having a large surface area are preferable. Examples of silica include wet silica, dry silica, and colloidal silica. These reinforcing fillers may be used alone or in combination of two or more.

  The compounding amount of the reinforcing filler in the elastomer composition is preferably in the range of 60 to 150 parts by mass with respect to 100 parts by mass of the elastomer component. When the compounding amount of the reinforcing filler is less than 60 parts by mass, the viscosity and flow resistance of the elastomer composition are low, and the damping performance of the seismic isolation device plug tends to be insufficient. On the other hand, when the compounding amount of the reinforcing filler exceeds 150 parts by mass, it is difficult to knead and it is difficult to obtain a uniform composition, and the repeated stability of the plug for a seismic isolation device is lowered.

  In addition to the elastomer component and the reinforcing filler, additives generally added to the elastomer composition such as a resin, an anti-aging agent, a wax, a plasticizer, and a softener may be added to the elastomer composition. . By blending the anti-aging agent with the elastomer composition, it is possible to suppress a change in physical properties of the plug for a seismic isolation device even after a long period of time. For such purposes, it is particularly effective to blend an antioxidant, an ozone deterioration inhibitor, a stabilizer, a flame retardant, and the like with the anti-aging agent.

  The powder is preferably a metal powder, and the metal powder preferably has a low environmental load. For example, iron powder, stainless steel powder, zirconium powder, tungsten powder, bronze (CuSn) powder, aluminum Powder, gold powder, silver powder, tin powder, tungsten carbide powder, tantalum powder, titanium powder, copper powder, nickel powder, niobium powder, iron-nickel alloy powder, zinc powder, molybdenum powder, and the like. One species may be used alone, or two or more species may be used in combination.

  In addition, since these metal powders may be metal oxide powders, metal compound powders such as metal oxide powders can also be suitably used as the powder. Among these powders, iron powder is particularly preferable. Iron powder is inexpensive and has high fracture strength compared to other metal powders. Also, the plug for seismic isolation devices based on iron powder is neither too hard nor too brittle. The damping performance can be demonstrated over a long period of time. Examples of the iron powder include reduced iron powder, electrolytic iron powder, sprayed iron powder, pure iron powder, and cast iron powder. Among these, reduced iron powder is preferable.

  In the composition for a plug material of the present invention, the content of the powder is preferably in the range of 50 to 74% by volume, and the particle size is preferably in the range of 0.1 μm to 2 mm. Moreover, it is preferable that the shape of the said powder is an indeterminate form from a viewpoint of improving damping performance. Here, the indefinite shape means that not only one type of shape such as a spherical shape but also shapes having various forms such as those having irregularities and protrusions are mixed.

  The composition for a plug material of the present invention is not particularly limited except that an elastomer composition obtained by blending a reinforcing filler with an elastomer component and powder are used, and can be produced, for example, as follows. it can.

  First, in the first step, an elastomer composition is prepared by adding a reinforcing filler and various compounding agents appropriately selected as necessary to the elastomer component and kneading them.

  Next, in the second step, powder is added to the elastomer composition and further kneaded. In the second step, it is preferable to mix the powder into a plurality of times, and it is possible to produce a uniform plug material composition by mixing the powder into a plurality of times.

  In the production of the composition for the plug material, an ordinary kneading apparatus such as a kneader or a Banbury mixer can be used. Also, the kneading conditions are not particularly limited, and the conditions that are normally used in the technical field can be appropriately modified to set conditions that allow the composition of the present invention to be sufficiently kneaded. it can. For example, the kneading conditions in the second step are preferably in the range of 20 to 40 rpm and a temperature of about 100 ° C.

  In order to suppress a decrease in the viscosity of the elastomer component, it is preferable that the rotational speed is low. The temperature is preferably a temperature sufficient to soften the elastomer composition in order to improve the dispersion of the powder in the elastomer composition. However, if the temperature is too high, the elastomer component deteriorates or is cooled. Takes too much time to reduce productivity. In addition, before discharging the kneaded composition, it is preferable to release the pressure and knead without pressure. By kneading without pressure, the composition does not solidify and the composition can be taken out. It becomes easy.

  Next, the manufacturing method of the said plug for seismic isolation devices is demonstrated. First, the ratio h between the thickness h (mm) and the diameter D (mm) of the cross section perpendicular to the thickness direction of the elastomer composition obtained by blending the elastomer component with a reinforcing filler and the powder. A plug material is manufactured by pressure molding into a shape satisfying / D satisfying 0.02 to 0.7.

  Next, a plurality of plug materials thus obtained are laminated to manufacture the plug for a seismic isolation device of the present invention. When a plug material having a ratio h / D within a range of 0.02 to 0.7 to a diameter D (mm) of a cross section orthogonal to the thickness direction is used as a plug for a seismic isolation device, an elastomer is used. The ratio h / D between the thickness h (mm) and the diameter D (mm) of the cross section perpendicular to the thickness direction of the elastomer composition obtained by blending a reinforcing filler into the component and the powder. It is manufactured by pressure molding into a shape satisfying 0.02 to 0.7.

  As described above, according to the method for manufacturing a plug for a seismic isolation device of the present invention, the air content is low and a partial variation in the air content is achieved by following the conventional process without using a new device. It becomes possible to manufacture a few plugs for seismic isolation devices.

Here, as a method of pressurizing the elastomer composition and the powder, there is a method of filling the elastomer composition and the powder in a mold and pressing them. The conditions for the press working are not particularly limited, and the conditions may be modified as appropriate to set conditions suitable for molding the plug material. For example, as the conditions for pressing, the pressing temperature is preferably in the range of room temperature to 90 ° C., and the molding pressure is preferably 0.6 tf / cm ² or more. In addition, the pressing direction in the press working is not particularly limited, but it is preferable to press in the vertical direction from two directions, and more preferably from the left and right directions.

  Hereinafter, the present invention will be described in more detail with reference to examples.

(Example plug materials 1 to 5, comparative example plug materials 1 and 2)
Using an kneader, an elastomer composition having the formulation shown in Table 1 was prepared, and then the elastomer composition and amorphous reduced iron powder having a particle size of 40 μm as a powder were kneaded at a volume ratio shown in Table 1. Thus, a composition for a plug material was prepared. Next, the plug material composition was placed in a mold and pressed under conditions of a temperature of 100 ° C. and a pressure of 1.26 tf / cm ² , and Example plug materials 1 to 5 shown in Table 2 and Comparative plug materials 1 and 2 were produced.

  A cylindrical hollow portion having a diameter of 45 mm is formed in the center of a laminate having an outer diameter of 225 mm, in which rigid plates [iron plates] and elastic plates [vulcanized rubber (G ′ = 0.4 MPa)] are alternately laminated. The example plug members 1 to 3 were overlapped and press-fitted into the hollow portion to produce a seismic isolation device having the example plug having the structure shown in FIG.

  Next, with respect to the seismic isolator, a dynamic tester was used to vibrate in the horizontal direction while applying a reference surface pressure in the vertical direction to cause shear deformation at a specified displacement, and the shear stress τd was measured. . The vibration displacement was set such that the total thickness of the laminate was 100%, the strain was 50, 100, 150, 200, and 250%, the vibration frequency was 0.33 Hz, and the vertical surface pressure was 10 MPa.

FIG. 5 shows the relationship between the horizontal displacement (δ) and the shear stress (τ) of the seismic isolation device. As the area of the region surrounded by the hysteresis curve in FIG. 5 increases, it means that more vibration energy can be absorbed. Here, the damping performance of the plug was evaluated based on the shear stress τd at a strain of 50%, 100%, 150%, 200%, and 250%. Incidentally, the shear stress τd, when the stress of displacement 0 in strain 150% was _{d 1} and _{d 2,} respectively, the average of the sum of the absolute values of _{d 1} and _{d 2} ({(the absolute value of _{d 1)} + ( the absolute value of d _2)} / ₂₎ were calculated from. The larger the value of τd, the better the plug attenuation performance.

* 1 Natural rubber, unvulcanized, RSS # 4
* 2 Polybutadiene rubber (low cis), unvulcanized, "Diene NF35R" manufactured by Asahi Kasei
* 3 "Seast 6P" made by carbon black, ISAF, Tokai Carbon
* 4 Resin, “Zeofine” manufactured by Nippon Zeon, “Nisseki Neopolymer 140” manufactured by Nippon Petrochemical, “Marcaretz M-890A” manufactured by Maruzen Petrochemical, “Zeofine”: “Nisseki Neopolymer 140”: “Marcaretz M” −890A ”= 40: 40: 20 (mass ratio)
* 5 Plasticizer, dioctyl adipate (DOA)
* 6 Other compounding agents, zinc white, stearic acid, anti-aging agent (“Anstage 6C” manufactured by Sumitomo Chemical), wax [“Proto Wax 1” manufactured by Nippon Oil Corporation], zinc white: stearic acid: anti-aging agent: wax = 4: 5: 3: 1 (mass ratio)

In addition, as a result of measuring the shear stress of the example plug, the shear stress was 80 or more as a target, specifically 84 kgf / cm ² .

DESCRIPTION OF SYMBOLS 1 Seismic isolation apparatus 2 Rigid board 3 Elastic board 4 Laminated body 5 Plug material 6 Flange board 7 Cover material 8 Plug for seismic isolation apparatus Thickness D Diameter of perpendicular section with respect to thickness direction S Area of perpendicular section with respect to thickness direction

Claims (2)

  The ratio of the thickness h (mm) by pressing the elastomer composition obtained by blending a reinforcing filler into the elastomer component and the powder, and the diameter D (mm) of the cross section perpendicular to the thickness direction A method for manufacturing a plug for a seismic isolation device, in which a plug material satisfying h / D of 0.02 to 0.7 is molded and the plug materials are laminated.   The ratio of the thickness h (mm) by pressing the elastomer composition obtained by blending a reinforcing filler into the elastomer component and the powder, and the diameter D (mm) of the cross section perpendicular to the thickness direction A method for manufacturing a plug for a seismic isolation device satisfying h / D of 0.02 to 0.7.

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