JPH1089407A - Base isolation structural body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the vibration damping characteristic, breakdown resistance characteristic and the cold resistance property, and while to restrict the plastic deformed amount of a soft layer small due to a load by forming a soft layer from vulcanized rubber, which includes silica as the reinforcing agent and silane coupling agent and silylizing agent. SOLUTION: A base isolation structural body M is provided with a disk- shaped two fitting flanges 1, 1, plural layers of disk-shaped soft layers 2..., which are laminated between both the fitting flanges 1, 1 alternately, plural hard layers 3, and a film layer 4 for coating the periphery of the soft layers 2 and the hard layers 3 between both the fitting flanges 1, 1. The soft layer 2 is made of vulcanized rubber, which includes silica as the reinforcing agent, silane coupling agent and silylizing agent. With this structure, the base isolation structural body, which has excellent vibration damping characteristic, breakdown resistance characteristic and cold resistance property and in which plastic deformed amount of the soft layer due to a load is restricted small so as to improve the creep resistance property.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic isolation structure provided on a foundation of a building such as a building or a bridge.

[0002]

2. Description of the Related Art In order to reduce the lateral acceleration of a building such as a building from the vibration frequency of an earthquake in order to reduce the lateral acceleration that the building receives in the event of an earthquake, the building is provided with a laterally extending structure. The insertion of a soft seismic isolation structure has been studied and is being put to practical use. Various structures have been proposed as the seismic isolation structure. One of the structures is a soft layer made of a material having rubber elasticity such as vulcanized rubber and a material having rigidity such as a steel plate. There is a laminated structure in which a plurality of hard layers are alternately laminated with a plurality of hard layers.

[0003] In the above-mentioned seismic isolation structure, the most important characteristic required for the soft layer is a characteristic of absorbing the energy of the deformation during a large deformation due to the occurrence of an earthquake to attenuate the vibration of the building (vibration damping characteristic). ). The soft layer also needs to have high resistance to external force (breakage resistance). In other words, a huge compressive load is always applied to the seismic isolation structure from the building even in normal times, and the outer periphery of the soft layer expands outward due to this compressive load, and a considerably large tensile force is applied to the surface. Since it is in a state where stress is applied, it is required not to be torn by this tensile stress, and at the time of large deformation due to the occurrence of an earthquake, a shear layer of about 200% is locally applied to the soft layer in some cases. Since there is a possibility of being deformed, it is required not to be destroyed by this deformation.

Therefore, natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), and the like are selectively used as base rubbers capable of forming a soft layer excellent in both of the above characteristics. In recent years, in order to further improve the vibration damping characteristics and fracture resistance characteristics of the soft layer, and to prevent the above characteristics from deteriorating particularly at low temperatures, and to improve the cold resistance of the soft layer, the above-described NR, It has been proposed to include silica as a reinforcing agent in a base rubber such as IR (for example, JP-A-6-57036, JP-A-7-57036).
-1264737).

[0005]

However, since silica has a hydrophilic surface due to the action of a silanol group (≡Si—OH), silica generally has poor dispersibility in a hydrophobic base rubber. It is not easy to disperse uniformly in the base rubber, the silanol group adsorbs a vulcanization accelerator compounded for vulcanization of the base rubber, and delays the vulcanization of the base rubber. The soft layer formed from such a silica-containing rubber composition has a large amount of plastic deformation when a load is continuously applied for a long period of time, so that the seismic isolation structure as a whole When seen, the amount of sinking (creep) in the vertical direction due to the weight of the building increases.

The plastic deformation of the soft layer due to the weight of the building and the creep of the seismic isolation structure due to the weight of the building are inevitable phenomena since the soft layer is formed of vulcanized rubber or the like. However, in seismic isolation structures that need to sustain the weight of the building for many years, if the amount of creep described above is large, for example, the structure may tilt or distort, or the seismic isolation function itself may occur. In order to prevent these problems from occurring, the amount of plastic deformation of the soft layer is reduced as much as possible to minimize the amount of creep of the seismic isolation structure. Improving the creep resistance of the body is an important issue.

An object of the present invention is to provide a seismic isolation structure having excellent vibration damping characteristics, fracture resistance, cold resistance, etc., and also having a small amount of plastic deformation of a soft layer due to a load, and therefore also having excellent creep resistance. Is to provide.

[0008]

JP-A-8-59899 discloses that a so-called silane coupling agent having reactivity and affinity for both a base rubber and silica is contained in a soft layer. According to this technique, there is a possibility that the above problems can be solved, the amount of plastic deformation of the soft layer can be reduced, and the creep resistance of the seismic isolation structure can be improved.

However, according to the study of the present inventors, the silane coupling agent binds to both the base rubber and silica and functions as a cross-linking agent between the two. It is clear that the layer causes a new problem that elongation of the base rubber is suppressed by the above-mentioned cross-linking, and the tensile elongation at break becomes small, hard and brittle, and the fracture resistance becomes insufficient. became.

Therefore, as a result of further study, it was found that the above silane coupling agent and an organosilane used in a so-called silylation reaction for introducing a silyl group into an inorganic substance or an organic substance, that is, a silylating agent may be used in combination. As a result, the present invention has been completed. That is, the seismic isolation structure of the present invention is obtained by alternately laminating a plurality of soft layers having rubber elasticity and a plurality of hard layers having rigidity,
The soft layer is made of a vulcanized rubber containing silica as a reinforcing agent, a silane coupling agent, and a silylating agent.

The above silylating agent mainly reacts with the silanol group on the silica surface to introduce the silyl group as described above, thereby eliminating the silanol group. In addition to improving the dispersibility of the vulcanization accelerator in the base rubber, it functions to suppress the adsorption of the vulcanization accelerator by the silanol group. Moreover, since the silylating agent does not react with the base rubber unlike the silane coupling agent and does not suppress the elongation of the base rubber, the silylation agent does not lower the fracture resistance of the seismic isolation structure. . Not only, as will be apparent from the results of Examples and Comparative Examples described below, when a silane coupling agent and a silylating agent are used in combination,
There is also a phenomenon in which the fracture resistance of the seismic isolation structure is improved as compared with the case of using the silane coupling agent alone.

Therefore, the seismic isolation structure of the present invention in which such a silylating agent is used in combination with silica and a silane coupling agent is excellent in vibration damping characteristics, fracture resistance, cold resistance, etc. due to the interaction of the above components. At the same time, it has excellent creep resistance. When a silane coupling agent and a silylating agent are used in combination, not only does the fracture-resistant property of the seismic isolation structure not decrease compared to the case of using the silane coupling agent alone, but the reason for further improvement is that silica The excess unreacted silylating agent polymerizes in the kneading and molding steps to form a long linear compound, which acts as a lubricant in the compounded rubber and increases the flexibility of the soft layer. It is conceivable to give.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The seismic isolation structure of the present invention will be described below.
This will be described with reference to FIG. 1 showing an example of the embodiment. As shown in FIG. 1, the seismic isolation structure M of this example has two disk-like mounting flanges 1, 1 and two disk-like mounting flanges 1, 1. A plurality of soft layers 2... And hard layers 3..., And between the mounting flanges 1, 1, a coating layer 4 that covers the outer periphery of the soft layers 2, hard layers 3. A through hole M1 is formed in the center of the seismic isolation structure M so as to penetrate the mounting flanges 1, 1, the soft layers 2 and the hard layers 3.

The mounting flange 1 and the hard layer 3 are each formed of a rigid material such as a steel plate, as in the prior art, and the upper mounting flange 1
A plurality of screw holes 12 into which bolts (not shown) for connecting the seismic isolation structure M to the foundation and the building are screwed, respectively, on the upper surface of the mounting flange 1 and the lower surface of the lower mounting flange 1.
... are formed.

In the present invention, the soft layer 2 is formed of a vulcanized rubber containing silica as a reinforcing agent, a silane coupling agent, and a silylating agent, as described above. As the base rubber constituting the vulcanized rubber, those excellent in vibration damping characteristics and breakage resistance characteristics are preferable as described above, and such base rubbers include the NR, IR, BR
And styrene-butadiene copolymer rubber (S
BR) is also preferably used. As the base rubber other than the above, for example, ethylene-propylene copolymer rubber (EP
M), acrylonitrile-butadiene copolymer rubber (NB
R), butyl rubber (IIR) and the like. These can be used alone or in combination of two or more.

As the silica to be contained in the base rubber, any hydrophilic or hydrophobic silica generally used as a rubber reinforcing agent can be used. The content of silica is not particularly limited, but is preferably about 20 to 200 parts by weight, more preferably about 30 to 150 parts by weight, based on 100 parts by weight of the base rubber.

If the content of silica is less than the above range, the effect of the silica to improve the vibration damping characteristics, fracture resistance, cold resistance, and the like may be insufficient. However, even if a large amount of a silane coupling agent and a silylating agent are contained, the creep resistance may decrease. As a silane coupling agent,
Any of various conventionally known silane coupling agents having reactivity and affinity for both the organic base rubber and the inorganic silica can be used. Such a silane coupling agent is not limited to, but may be, for example, a compound represented by the following general formula (1):

[0018]

Embedded image

[0019] [wherein R ¹ represents vinyl, glycidoxy, methacryloyl, amino, mercapto, imino, the organofunctional group having at least one group selected from the group consisting of epoxy and halogenated alkyl, R ^2, R ³
And at least one of R ⁴ is the same or different and represents an alkoxy group or a halogen atom, and the other represents the same or different alkyl group. Or a compound represented by the general formula (2):

[0020]

Embedded image

[Wherein R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ represent the same or different alkoxy groups, and R ¹¹ and R ¹² represent the same or different alkylene groups. ] The compound represented by this is mentioned. Specific examples of the former silane coupling agent represented by the general formula (1) include, for example, vinyltrichlorosilane, vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, and γ- (methacrylic acid). (Roxypropyl) trimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β- (aminoethyl ) -Γ-aminopropyltrimethoxysilane, N-β
-(Aminoethyl) -γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane,
N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-
Chloropropyltrimethoxysilane and the like can be mentioned.

As a specific example of the latter silane coupling agent represented by the general formula (2), for example, bis (3-
Triethoxysilylpropyl) tetrasulfane. These can be used alone or in combination of two or more. The content of the silane coupling agent is not particularly limited.
It is preferably about 0.5 to 20 parts by weight, more preferably about 1 to 5 parts by weight based on parts by weight.

If the content of the silane coupling agent is less than the above range, the effect of the silane coupling agent to prevent the creep resistance from lowering may be insufficient. In such a case, the fracture resistance may be reduced. As the silylating agent, any of various organosilanes capable of reacting with silanol groups on the silica surface to eliminate the silanol groups can be used.

Examples of such a silylating agent include organohalosilanes, organoalkoxysilanes, and silazanes. In particular, the following general formula (3):

[0025]

Embedded image

[Wherein at least one of R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ is the same or different and represents an alkoxy group or a halogen atom, and the other is the same or different and represents a hydrogen atom, an alkyl group or an aryl group. Is shown. The organohalosilanes and organoalkoxysilanes represented by the following formulas are preferably used.

Specific examples of the organohalosilane include, for example, methyldichlorosilane, dimethyldichlorosilane (DMDS), octadecyltrichlorosilane (ODS), trimethylchlorosilane (TMCS), t
-Butyldimethylchlorosilane (TBMS) and the like. Specific examples of the organoalkoxysilane include, for example, isobutyltrimethoxysilane, n-hexyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, and the like.

Further, specific examples of the silazane include, for example, hexamethyldisilazane (HMDS). In addition to the above, for example, N-trimethylsilylacetamide (MSA), N, O-bis (trimethylsilyl) acetamide (BSA), N-trimethylsilylimidazole (TSIM), N, N′-bis (trimethylsilyl) urea (BTSU) , N-trimethylsilyl-N, N'-diphenylurea (TDPU), N,
O-bis (trimethylsilyl) trifluoroacetamide (BSTFA), N, O-bis (trimethylsilyl)
Carbamate, N, O-bis (trimethylsilyl) sulfamate, trimethylsilyltrifluoromethanesulfonic acid and the like can also be used as the silylating agent.

These can be used alone or in addition to
More than one species may be used in combination. The content of the silylating agent is not particularly limited, but is preferably about 4 to 40 parts by weight relative to 100 parts by weight of silica,
More preferably, it is about 30 parts by weight. When the content of the silylating agent is less than the above range,
There is a possibility that the effect of preventing the fracture resistance from lowering may be insufficient. Conversely, when the amount exceeds the above range, the amount of the unreacted silylating agent in excess with respect to silica becomes too large. Such excess silylating agent precipitates on the surface of the rubber composition before vulcanization or on the surface of the soft layer after vulcanization. At that time, the rubber composition is precipitated together with other additives and the like compounded in the rubber, so that the compounding of the rubber composition may be disordered and the desired physical properties may not be obtained. Further, the adhesion strength between the soft layer and the hard layer or the flange may be reduced due to the precipitation of the silylating agent.

In the same manner as in the prior art, a vulcanizing agent, a vulcanization accelerator, a vulcanization accelerator, a vulcanization retarder, a reinforcing agent other than silica, a filler, a softener, a plasticizer, and a tackifier may be added to the base rubber. Agents and other various additives may be added as necessary. Among the above, examples of the vulcanizing agent include sulfur, organic sulfur-containing compounds, organic peroxides, and the like. Examples of the organic sulfur-containing compound include N, N'-dithiobismorpholine and the like. Examples of the peroxide include benzoyl peroxide, dicumyl peroxide and the like.

Examples of the vulcanization accelerator include thiuram vulcanization accelerators such as tetramethylthiuram disulfide and tetramethylthiuram monosulfide; zinc dibutyldithiocarbamate, zinc diethyldithiocarbamate and dimethyldithiocarbamate. Dithiocarbamic acids such as sodium and tellurium diethyldithiocarbamate;
Organic accelerators such as thiazoles such as 2-mercaptobenzothiazole and N-cyclohexyl-2-benzothiazolesulfenamide; thioureas such as trimethylthiourea and N, N'-diethylthiourea; or slaked lime, magnesium oxide; Titanium oxide, litharge (Pb
O) and the like.

Examples of the vulcanization accelerator include metal oxides such as zinc white, stearic acid, oleic acid, and the like.
And fatty acids such as cottonseed fatty acids. Examples of the vulcanization retarder include aromatic organic acids such as salicylic acid, phthalic anhydride and benzoic acid; N-nitrosodiphenylamine,
And nitroso compounds such as -nitroso-2,2,4-trimethyl-1,2-dihydroquinone and N-nitrosophenyl-β-naphthylamine.

The above-mentioned vulcanizing agent, vulcanization accelerator, vulcanization accelerating aid and vulcanization retarder are combined in a total amount of base rubber 10
It is preferably about 4 to 15 parts by weight with respect to 0 parts by weight. Examples of the antioxidant include imidazoles such as 2-mercaptobenzimidazole; phenyl-α-naphthylamine, N, N′-di-β-naphthyl-p-phenylenediamine, N-phenyl-N′-isopropyl-
amines such as p-phenylenediamine; and diphenols such as di-t-butyl-p-cresol and styrenated phenol.

The amount of the antioxidant is preferably about 1 to 10 parts by weight based on 100 parts by weight of the base rubber. Carbon black is mainly used as a reinforcing agent other than silica. In addition, inorganic reinforcing agents such as silicate-based white carbon, zinc white, surface-treated precipitated calcium carbonate, magnesium carbonate, talc, and clay; Organic reinforcing agents such as malonindene resin, phenolic resin and high styrene resin (styrene-butadiene copolymer having a high styrene content) can also be used.

Examples of the filler include calcium carbonate, clay, barium sulfate, diatomaceous earth and the like. The amount of the reinforcing agent and / or filler other than silica is preferably about 5 to 50 parts by weight based on 100 parts by weight of the base rubber. Examples of the softener include fatty acids (such as stearic acid and lauric acid), cottonseed oil, tall oil,
Various softening agents of vegetable oil type, mineral oil type, and synthetic type, such as asphalt substances and paraffin wax, may be mentioned.

The amount of the softener is preferably about 10 to 100 parts by weight based on 100 parts by weight of the base rubber. Examples of the plasticizer include various plasticizers such as dibutyl phthalate, dioctyl phthalate, and tricresyl phosphate. The blending amount of the plasticizer is preferably about 5 to 20 parts by weight based on 100 parts by weight of the base rubber.

Further, examples of the tackifier include coumarone / indene resin, aromatic resin, mixed aromatic / aliphatic resin, rosin resin, cyclopentadiene resin and the like. The amount of the tackifier is preferably about 5 to 50 parts by weight based on 100 parts by weight of the base rubber.

In addition to the above, a dispersant, a solvent and the like may be appropriately blended in the base rubber. The coating layer 4 is provided on the foundation of the building as described above, and improves the weather resistance of the seismic isolation structure used for a long period of time. In particular, the soft layer 2 causes oxidation deterioration, ozone deterioration, and the like. It may be formed of the same base rubber as the soft layer 2, but is preferably formed of a base rubber having excellent weather resistance.

Examples of the base rubber having excellent weather resistance for forming the coating layer 4 include, but are not limited to, brominated paramethylstyrene-isobutylene copolymer, II
R, EPM and the like. The coating layer 4 is formed by adding a vulcanizing agent, a vulcanization accelerator, a vulcanization accelerator, a vulcanization retarder,
It is formed by a rubber composition to which a reinforcing agent, a filler, a softener, a plasticizer and other various additives are added.

To manufacture the seismic isolation structure M of the present invention,
First, an unvulcanized rubber composition for the soft layer 2 manufactured by kneading the above-described components using, for example, a closed kneader or the like is formed into a sheet shape using a roller head extruder, and the like. After being punched into a disk shape, a plurality of the punched sheets are laminated together with a plurality of mounting flanges 1, 1, and a plurality of hard layers 3 in the order shown in FIG.

Next, a sheet of the above-described unvulcanized rubber composition for the coating layer 4 is wound around portions corresponding to the soft layers 2... And the hard layers 3. .
At this time, a vulcanizing adhesive is applied between each layer of the mounting flanges 1, 1 and the sheets of the soft layers 2 and the layers of the hard layers 3 and between the above-mentioned layers and the sheet for the covering layer 4, respectively. It may be interposed.

When the above assembly is heated and pressurized at a predetermined temperature and pressure, the unvulcanized sheet is vulcanized to form the soft layers 2 and the coating layer 4 and the soft layer 2. The layers 2 and the covering layer 4, the mounting flanges 1 and 1, and the hard layers 3 are vulcanized and bonded to each other.
The seismic isolation structure M shown in FIG. The above seismic isolation structure M
The through hole M1 formed at the center of
It is for positioning the mounting flanges 1, 1 and the sheets to be the soft layers 2 and the hard layers 3, and may be omitted depending on the manufacturing method.

The seismic isolation structure M shown in FIG.
The outer diameter of the hard layers 3 is smaller than the outer diameter of the mounting flanges 1, 1.
Although only the outer periphery of the soft layers 2 and the hard layers 3 was covered by the covering layer 4, the outer diameters of the mounting flanges 1, 1 and the soft layers 2 and the hard layers 3 The outer periphery of all members may be covered with the covering layer 4.

Alternatively, the coating layer 4 may be omitted. In addition, various design changes can be made without departing from the scope of the present invention.

[0045]

The present invention will be described below with reference to examples and comparative examples. Example 1 <Preparation of rubber composition> NR [SMRC
V60] with respect to 100 parts by weight, silica (Nipsil VN3 manufactured by Nippon Silica Co., Ltd.) as a reinforcing agent, 40 parts by weight, and bissilane belonging to the compound represented by the general formula (2) as a silane coupling agent. (3-triethoxysilylpropyl) tetrasulfan [Si69 manufactured by Degussa] 5
Parts by weight, 20 parts by weight of n-hexyltrimethoxysilane as a silylating agent (KBM3063 manufactured by Shin-Etsu Chemical Co., Ltd.), and the following components are blended and kneaded with an internal kneader to obtain a rubber composition. Was prepared.

[0046] <Production of seismic isolation structure> The above rubber composition is formed into a sheet having a width of 400 mm and a thickness of 2.1 mm by a roller head extruder, and has a through hole with an outer diameter of 180 mm and an inner diameter of 21 mm at the center thereof. It was punched into a disk.

Next, fifteen disk-shaped sheets (hard layer) having a thickness of 3 mm and having a through hole having an inner diameter of 21 mm at the center of the disk-shaped sheet were used. And two 19.8 mm-thick disc-shaped steel plates (mounting flanges) having an outer diameter of 196 mm and a through hole having an inner diameter of 21 mm at the center thereof are stacked one above the other. And crimped with a hydraulic press.

Next, a bromide of paramethylstyrene-isobutylene copolymer [Exxon Chemical Co., Ltd.] was placed between the two mounting flanges of the laminate and around the sheet and the steel plate to be the soft and hard layers. EXXPRO
A sheet having a thickness of 3.0 mm made of EMDX 89-4] was wound into a dedicated mold and heated and vulcanized while being pressed by a hydraulic press. The vulcanization conditions were a vulcanization pressure of 200 kgf / cm ² and a vulcanization temperature of 150 ° C.

After vulcanization, the mold was taken out of the mold and
The overall thickness is 108.6 mm, the inner diameter of the through hole M1 is 20 mm, the distance between the two mounting flanges 1 and 1 is 69 mm, and the thickness of one layer of the soft layer 2 is 1.8 mm
A model of the seismic isolation structure was manufactured. Comparative Example 1 A model of a seismic isolation structure having the same dimensions was manufactured in the same manner as in Example 1 except that neither the silane coupling agent nor the silylating agent was added to the rubber composition for the soft layer. .

Example 2 The amount of silica in the rubber composition for the soft layer was 110
A model of a seismic isolation structure having the same dimensions was manufactured in the same manner as in Example 1 except that the weight was used. Example 3 The amount of silica in the rubber composition for the soft layer was 170
A model of a seismic isolation structure having the same dimensions was manufactured in the same manner as in Example 1 except that the weight was used.

The following tests were performed on the model of the seismic isolation structure manufactured in each of the above Examples and Comparative Examples, and the rubber composition for the soft layer used in each of the Examples and Comparative Examples, and the characteristics were measured. evaluated. Creep resistance test of seismic isolation structure The model of the seismic isolation structure M manufactured in each of Examples and Comparative Examples was
After standing for one day and night under the condition of the atmospheric temperature of 60 ° C., the upper and lower mounting flanges 1 and 5 are placed under the above temperature condition.
As shown by the black arrow in FIG. 2 (a), using a 0 ton creep tester [manufactured by Omi Degree Co., Ltd.]
0 kgf / cm ² ].

Then, when the load is started for 1 minute, the time is counted from the point when the time has elapsed and 100,000 minutes (about 1666.7 minutes).
After a lapse of time, the distance between the two mounting flanges 1 and 1 was measured, and the amount of decrease (mm) from the original distance (= 69 mm) was determined as the creep amount. Destruction resistance test of seismic isolation structure The model of the seismic isolation structure M manufactured in each of Examples and Comparative Examples
As shown by a black arrow in FIG. 2B, a vertical load [80 kgf / cm ² ] is applied between the upper and lower mounting flanges 1 and 1 at an ambient temperature of 20 ° C. Was displaced in the horizontal direction at a displacement speed of 20 mm / min, as indicated by white arrows in the figure, to shear-deform the soft layer.

The stress at the time when the peeling fracture occurred in the soft layer was defined as the stress at fracture [kgf / cm ² ] and the elongation D
(%) Was recorded as elongation at break. Elongation D (%)
Is the horizontal displacement d [mm] of the upper flange 1
And the total thickness t of the soft layer (in this case, 1.8 mm × 15 sheets = 27 mm), it was determined by the following formula (i): D (%) = d / t × 100 (i).

Measurement of Tensile Elongation at Break of Vulcanized Rubber The rubber composition used in each of the examples and comparative examples was extruded into a sheet having a thickness of 2 mm, and press-vulcanized to produce a vulcanized sheet having a thickness of 2 mm. . Then, the above vulcanized sheet was punched out to prepare a dumbbell-shaped No. 3 test piece specified in JIS K6301 “Vulcanized Rubber Physical Test Method”. The tensile elongation at break of this test piece was measured at a tensile speed of 500 mm / min. The measurement was performed using an all-purpose tensile tester under the conditions of an ambient temperature of 20 ° C.

Table 1 shows the above results.

[0056]

[Table 1]

From the results of Example 1 and Comparative Example 1 in Table 1, it can be seen that Example 1 in which the soft layer contains silica, a silane coupling agent and a silylating agent is a comparative example in which only the above silica is contained. Compared to No. 1, it was found that the creep resistance could be improved while maintaining the fracture resistance. Further, from the results of Example 1 and Examples 2 and 3, it was found that in the combination system of the above three, by increasing the content of silica, it was possible to improve the fracture resistance while maintaining the creep resistance. .

Examples 4 to 6 The mixing amount of the silane coupling agent in the rubber composition for the soft layer was 1 part by weight (Example 4), 10 parts by weight (Example 5) and 15 parts by weight (Example 6). A model of a seismic isolation structure having the same dimensions was manufactured in the same manner as in Example 2 except that the above-mentioned was used. A model of the seismic isolation structure manufactured in each of the above embodiments,
The above-described tests were performed on the rubber composition for the soft layer used in each example, and the characteristics were evaluated. The results are shown in Table 2 together with the results of Example 2.

[0059]

[Table 2]

From the results in Table 2, it can be seen that in the combination system of silica, silane coupling agent and silylating agent, the creep resistance can be improved by increasing the content of the silane coupling agent. It has been found that the fracture resistance tends to decrease. Examples 7 to 9 The compounding amount of the silylating agent in the rubber composition for the soft layer was 5
Parts by weight (Example 7), 30 parts by weight (Example 8) and 4 parts by weight
A model of the seismic isolation structure having the same dimensions was manufactured in the same manner as in Example 2 except that the weight was set to 0 parts by weight (Example 9).

Comparative Example 2 A model of a seismic isolation structure having the same dimensions was manufactured in the same manner as in Example 2 except that the silylating agent was not added to the rubber composition for the soft layer. With respect to the model of the seismic isolation structure manufactured in each of the above Examples and Comparative Examples, and the rubber composition for the soft layer used in each of the Examples and Comparative Examples, the above-described tests were performed to evaluate the characteristics. The results are shown in Table 3 together with the results of Example 2.

[0062]

[Table 3]

From the results shown in Table 3, it can be seen that in the combination system of silica, silane coupling agent and silylating agent, the content of the silylating agent was increased to maintain the creep resistance and the fracture resistance. Was found to be able to improve. Examples 10 and 11 The mixing amount of the silylating agent in the rubber composition for the soft layer was changed to 3
0 parts by weight (Example 10) and 40 parts by weight (Example 1)
A model of a seismic isolation structure having the same dimensions was manufactured in the same manner as in Example 5 except that 1) was adopted.

Comparative Example 3 A model of a seismic isolation structure having the same dimensions was manufactured in the same manner as in Example 5 except that the silylating agent was not added to the rubber composition for the soft layer. With respect to the model of the seismic isolation structure manufactured in each of the above Examples and Comparative Examples, and the rubber composition for the soft layer used in each of the Examples and Comparative Examples, the above-described tests were performed to evaluate the characteristics. The results are shown in Table 4 together with the results of Example 5.

[0065]

[Table 4]

From the results in Table 4, it can be seen that even in a system containing a large amount of silica, increasing the content of the silylating agent
It was found that the fracture resistance can be improved while maintaining the creep resistance. Example 12 Same as Example 2 except that 5 parts by weight of vinyltriethoxysilane [TSL8311 manufactured by Toshiba Silicone Co., Ltd.] belonging to the compound represented by the general formula (1) was used as a silane coupling agent. Then, a model of the seismic isolation structure having the same dimensions was manufactured.

Example 13 BR [BR55F manufactured by Asahi Kasei Corporation] 1 as a base rubber
In the same manner as in Example 2 except that 00 parts by weight was used,
A model of the seismic isolation structure of the same dimensions was manufactured. With respect to the model of the seismic isolation structure manufactured in each of the above Examples and the rubber composition for the soft layer used in each of the Examples, the above-described tests were performed to evaluate the characteristics. The results are shown in Table 5 together with the results of Example 2.

[0068]

[Table 5]

From the results shown in Table 5, it can be seen that according to the combination of silica, silane coupling agent and silylating agent, both high creep resistance and fracture resistance can be achieved even with different blending systems. I knew I could do it.

[0070]

As described above in detail, according to the present invention, by using silica, a silane coupling agent and a silylating agent in combination, excellent vibration damping characteristics, breakage resistance, cold resistance, etc. are obtained. In addition, since the amount of plastic deformation of the soft layer due to the load is small, it has a specific effect of providing a seismic isolation structure having excellent creep resistance.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing an example of an embodiment of a seismic isolation structure of the present invention.

FIG. 2 (a) is a diagram for explaining a method of a creep resistance test performed on a model of a base-isolated structure manufactured in an example of the present invention and a comparative example, and FIG. FIG. 4 is a view for explaining a method of a fracture resistance test.

[Explanation of symbols]

 M seismic isolation structure 2 Soft layer 3 Hard layer

Claims (3)

[Claims] A seismic isolation structure in which a plurality of soft layers having rubber elasticity and hard layers having rigidity are alternately laminated by a plurality of layers, wherein the soft layer comprises silica as a reinforcing agent, and silane coupling. A seismic isolation structure characterized by being formed of a vulcanized rubber containing an agent and a silylating agent. 2. A silane coupling agent represented by the general formula (1): [Wherein R ¹ is vinyl, glycidoxy, methacryloyl,
An organic functional group having at least one group selected from the group consisting of amino, mercapto, imino, epoxy and alkyl halide, wherein at least one of R ² , R ³ and R ⁴ is the same or different Represents an alkoxy group or a halogen atom, and the others represent the same or different alkyl groups. A compound represented by the general formula:
(2): [Wherein R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ represent the same or different alkoxy groups, and R ¹¹ and R ¹² represent the same or different alkylene groups. The seismic isolation structure according to claim 1, which is at least one of the compounds represented by the following formula: [3] The silylating agent has a general formula (3): [Wherein at least one of R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ is the same or different and represents an alkoxy group or a halogen atom, and the other is the same or different and represents a hydrogen atom, an alkyl group or an aryl group. The seismic isolation structure according to claim 1, which is a compound represented by the following formula: