JPH1037212A - Vibration-isolation ground - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a vibration isolator which can also isolate traffic vibrations, etc., by installing a columnar hollow section to a composite laminate, in which rigid plates having rigidity and flexible plates having viscoelasticity are laminated alternately, and disposing a damping manifesting body such as lead into the hollow section. SOLUTION: A columnar plastic article such as lead 30 is arranged into the hollow section of the composite laminate 28 of a rigid plate 24 made up of a metal, etc., and a flexible plate 26 consisting of a rubber, etc., and a guard ring 31 is laminated around the plastic article, and a vibration isolation structure is formed. A rigid material such as the metal, ceramics, FRPs, etc., is used as the rigid plate 24 and the generation of a buckling phenomenon is prevented, and an admixture such as a thermoplastic rubber, a urethane rubber, asphalt, etc., is employed as the flexible plate. The vibration isolation structure is interposed between a pile foundation and a house support floor and a vibration isolation ground is formed, and a comparatively lightweight building such as a detached house is installed onto the ground. Small vibrations such as traffic vibrations can also be obviated. Accordingly, the vibration isolation ground having high performance and excellent durability can be acquired at low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base-isolated ground for supporting a lightly-loaded structure such as a detached house, an apartment, an apartment or the like, that is, a base-isolated artificial ground.
Specifically, it relates to seismic isolation ground suitable for protecting structural houses and the like from earthquake damage.

[0002]

2. Description of the Related Art Seismic isolation of high-load structures such as general concrete buildings and bridges is rapidly spreading. In particular, since the Great Hanshin Earthquake, research and development has been actively promoted with the aim of seismic isolation of lightly loaded structures such as small condominiums, apartments, and general houses, and some of them have been put into practical use.

[0003] By the way, the improvement of the earthquake resistance of ordinary houses has conventionally been aimed at improving the strength of the structure itself. For example, reinforcement of beams and braces by wooden frame structure,
Increasing the yield strength of a 2 × 4 house or a prefabricated house by a wall construction method, and the like. However, if such reinforcement is advanced, the height and size of the room, the frontage, the window, the ceiling, and the like are restricted, and the user cannot freely design the system.

[0004] For this reason, if the ordinary house is seismically isolated by means other than the improvement of the strength of the housing structure as described above to improve the earthquake resistance, the above problem can be solved. For example, if a seismic isolation rubber can be placed between the foundation of the house and the structure to protect the structure from earthquake motion, there is no need to make the structure itself a bearing structure. Therefore, it is possible to reduce cost by reducing the number of structural means. In such a case, there are no restrictions on the design that occurs in the load-bearing structure, and the size of the room, the size of the opening window, the density of the columns, the free design of the ceiling, etc. It also has the advantage that materials that are said to be inferior can be used.

[0005] However, seismic isolation of a lightly-loaded structure has a very difficult problem. First, when the structural body has a small mounting weight such as a detached house, the material of the soft plate needs to have low spring rigidity and low elasticity. Although such a seismic isolation device exhibits an excellent seismic isolation effect, it is affected by wind sway, traffic vibration and the like. For this reason, it has been difficult to directly apply the seismic isolation structure that has been conventionally used for seismic isolation of middle-rise and low-rise buildings and bridges.

Secondly, a lightly-loaded structure such as a detached house generally has a lower cost than a heavy-load structure such as a building or a bridge.
Since the cost ratio of seismic isolation to the cost of the structure is high, low-cost seismic isolation devices are currently strongly demanded.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been made in view of such a conventional technique, and has a high performance and high performance in which a seismic isolation device can be suitably used for a lightweight object such as a detached house. An object of the present invention is to propose a low-cost seismic isolation ground which is excellent in durability without buckling deformation or cutting failure, can prevent traffic vibration and the like, and is low in cost.

[0008]

The seismic isolation ground of the present invention is a seismic isolation ground having a foundation, a seismic isolation structure, and a house supporting floor, wherein the seismic isolation structure has rigidity. Inside a composite laminate in which a plurality of hard plates and a plurality of soft plates having viscoelastic properties are alternately laminated, a columnar hollow portion penetrating the composite laminate is provided, and the composite laminate is isolated. A means for improving seismic characteristics is provided.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The seismic isolation ground of the present invention includes (a) a base portion, (b) a seismic isolation structure, and (c) a house support floor as main components, and a structure such as a house is disposed thereon. The above components are connected by bolts or the like.

FIG. 1A is a schematic cross-sectional view showing one embodiment of the seismic isolation ground 10 of the present invention, and FIG. FIG. 3 is a schematic cross-sectional view showing a state in which the cover is folded. In the base-isolated ground 10, a base-isolated structure 16 is disposed above a pile 14 constituting a foundation, and a housing support floor 18 is connected to and disposed above these.

The (a) foundation portion of the seismic isolation ground of the present invention has a function of supporting the entire seismic isolation ground and the structure disposed thereon. It is desirable to have a frame-type foundation.

As shown in FIG. 2A, the pile 14 used for the pile foundation is generally a columnar rod, and a general-purpose pile used for a foundation of a building can be applied. Generally, a slight momentary load is applied to the pile 14 during an earthquake, so that a bending moment is generated in the pile. In order to prevent the deformation and the settlement of the pile due to the bending moment, it is more preferable that the pile used for such a pile foundation is provided with a pile head cap 20 at the pile head [FIG. 2 (B)]. Pile head cap 2
0 is preferably formed of a material such as metal or concrete. As the size, when the diameter R of the pile head cap 20 and the diameter of the pile 14 are r, R / r
It is preferably in the range of ≧ 2. FIG. 2A is a partial cross-sectional view showing a state in which seismic isolation structures 16 are stacked on a pile 14 serving as a foundation, and FIG. 2B shows a pile head cap 20 on a pile head of the pile 14. It is a fragmentary sectional view showing the state where it was attached.

Referring to the pile head cap 20, FIG.
As shown in (C), a plurality of piles 14 (a), 14
(B) and 14 (c), it is also effective to cover them with one pile head cap 20 (b).

The shape of the pile 14 is not limited to the above-mentioned columnar shape. For example, in order to increase the bending resistance of the pile per weight, FIG.
A hollow pile as shown in (D) can also be suitably used.

As the pile foundation used as the base part for the seismic isolation ground of the present invention, in addition to the columnar pile 14 described above, FIG.
(A), plate-like piles 22 (a), 22 shown in (B)
(B) is also effective. FIGS. 3A and 3B are partial cross-sectional views each showing a state in which the seismic isolation structure 16 is fixed to the upper part of the plate-like piles 22 (a) and 22 (b) which are the base portions.
The plate-shaped pile may be a flat plate as shown in FIG. 3 (A), or may be a flat plate having a flange portion protruding in the ground direction around as shown in FIG. 3 (B). The size of such a plate-shaped pile can be appropriately selected depending on the weight of the structure used and the seismic isolation performance, but the soft plate diameter of the seismic isolated structure used together is x, and the length of one side of the plate-shaped pile is When the length (or diameter) is X, these relationships are preferably in the range of X / x ≧ 3, and more preferably X / x ≧ 4.

As a mode suitably used as the base part for the base isolation ground of the present invention, there is a top type foundation, that is, a concrete block in the form of a top. FIG. 4 (A)
It is the schematic which shows an example of the shape of a top type | form. The degree of inclination of the side surface of the top of the top 23 of the top 23 (the value of θ in the figure) can be arbitrarily selected depending on the purpose.
It is preferable that the angle is about °.

When the top 23 is used, a plurality of the bases 23 are connected in a cross-girder form by connecting bars 21 called fishing bars, and the space below the top 23 is filled with broken stones or the like. It is common that it is. FIG. 4B is a schematic view showing a state in which the tops 23 are connected in a plane, and FIG. 4C is a plan view in which the tops 23 are connected in a two-tiered manner. It is a schematic diagram showing a state.

The connection between the frame type foundation 23 and the seismic isolation structure 16 is performed, for example, by installing a connection plate 25 on the top of the frame type base 23 connected in a plane, and connecting the connection plate 25 and the seismic isolation structure 16.
Can be fixed by bolts or the like. FIG. 5 is a schematic cross-sectional view showing a state in which the seismic isolation structure 16 is connected to the top 23 of the frame.

Due to its shape,
In addition to the effect of suppressing land subsidence and the effect of increasing the bearing capacity, the effect of suppressing eccentric load is also large, and has its own anti-vibration and vibration damping effects. Furthermore, it can be said that it is one of the most suitable as the base for the seismic isolation ground of the present invention because transportation and construction can be easily performed.

The (b) seismic isolation structure used in the seismic isolation ground of the present invention is a hybrid isolation structure that is effective for both high shear vibrations such as earthquakes and microvibrations such as wind turbulences, because the seismic isolation structure is for light loads. A seismic structure, that is, a structure in which means for improving the seismic isolation characteristics of the composite laminate are arranged in a hollow portion provided inside a composite laminate in which hard and soft plates are alternately laminated. is there.

Here, (b) the composite laminate constituting the seismic isolation structure will be described. The material used for the viscoelastic soft plate constituting the composite laminate is 50
% Modulus refers to one having characteristics of 1 to 5 kgf / cm ² , more preferably 1.5 to 3 kgf / cm ² .
The 50% modulus of various materials is, for example, JIS K6
301 and K6394.

Here, as the material having the viscoelastic property, organic materials such as thermoplastic rubber, urethane rubber, various vulcanized rubbers, unvulcanized rubber, finely crosslinked rubber, plastics, foams thereof, Various materials, such as inorganic materials such as asphalt and clay, and mixed materials thereof, having the above viscoelastic properties can be used.

These materials are formed into a flat plate and used as a soft plate. The shape of the soft plate is not particularly limited, but the seismic isolation device of the present invention needs a hollow shape at the center since a columnar hollow portion is required in the composite laminate. Usually, a so-called cylindrical shape having a hollow portion at the center is used, and each soft plate has a donut shape, but may be a square shape as long as it has a hollow portion. The thickness of the soft plate is not particularly limited, and can be selected according to the material to be used and the desired seismic isolation performance. In general, a thickness of about 1 to 4 mm is used.

These materials may be used alone or as a mixture of a plurality of types. The materials may be entirely formed of a uniform material. The inner portion has a high damping material, and the outer portion has a creep performance. It is also possible to use a combination of two or more kinds with a good and soft material.

The hard plate constituting the seismic isolation structure may be metal, ceramics, plastics, FR, or the like.
Various materials having required rigidity, such as P, polyurethane, wood, paper board, slate board, decorative board, etc., can be used. Here, the required rigidity largely depends on design conditions, but means rigidity that does not easily cause a buckling phenomenon when subjected to shear deformation.

The thickness and shape of the hard plate are not particularly limited.
The thickness can be selected depending on the material to be used and the desired seismic isolation performance. Generally, the thickness is about 0.5 to 5 mm. The shape is arbitrary as well as the soft plate to be laminated, except that it has a hollow portion at the center, but usually the same shape as the soft plate used together is used.

The soft plate and the hard plate are alternately laminated in a plurality of stages to form a composite laminate. The soft plate and the hard plate have different shapes, areas and thicknesses depending on the required seismic isolation performance as described above, but the composite laminate improves the seismic isolation performance of the composite laminate inside as described above. Since a hollow portion for arranging the means is required, usually, a soft plate and a hard plate both have the same donut disk shape or a rectangular plate shape having a hollow portion, and those having the same surface area are generally used. Have been.

As described above, in this composite laminate, a doughnut-shaped hard plate and a soft plate are both preferably used. In this case, the diameter of the composite laminate in plan view is D, When the diameter of the hollow portion in plan view is d, it is preferable that D and d have a relationship satisfying the following expression.

0.8 ≧ d / D ≧ 0.1, more preferably 0.6 ≧ d / D ≧ 0.1 When d / D exceeds 0.8, the spring stiffness of the composite laminate existing in the surroundings The balance between the plastic deformation force and frictional force caused by the means to improve seismic isolation performance located in the hollow part is lost,
There is a risk that it will not be able to return to its original position after receiving a severe type due to an earthquake or the like. If d / D is less than 0.1, the effect of improving seismic isolation performance is small, and the desired damping effect cannot be obtained. Are not preferred. Even when the composite laminate to be used is not cylindrical having a hollow portion, it is preferable that the area ratio between the composite laminate and the hollow portion is in a range derived from the above equation.

Specifically, for example, when D is 50 to 50,
Those having 0 mm and d of about 3 to 300 mm are preferable.

As means (attenuating body) for improving the seismic isolation performance arranged in the columnar hollow portion of the composite laminate constituting the seismic isolation structure according to the present invention, for example, (1) lead or the like Placing a plastic material in a hollow part, (2) laminating and filling a friction plate in the hollow part, (3) filling a hard granular material in the hollow part,
And other means.

FIG. 6 shows a seismic isolation structure 1 in which a columnar lead 30 is arranged in a hollow portion of a composite laminate 28 composed of a hard plate 24 and a soft plate 26, and a protective ring 31 is laminated and arranged around the lead.
FIG. As the columnar plastic material, a plastically deformable metal or polymer material such as lead or tin is used, and among them, lead is preferable. Further, a protective ring 3 arranged around the plastic material so as not to damage the columnar plastic material.
1 is preferably formed of a material having a lower elasticity than the material of the plastic material and capable of sufficiently constraining the plastic material, for example, a thermoplastic such as polyamide, polyethylene, polypropylene, polystyrene, or silicone. FRP using them as a matrix can be mentioned. These may be used alone or in combination of two or more. As described above, when the plastic material 30 such as lead and the protective ring 31 are arranged in the entire hollow portion of the composite laminate 28, the elasticity at low strain, the low elasticity at high strain, and the high damping property are combined, so that the It can be effective against wind and wind sway.

Here, the outer diameter is 250 mm, the inner diameter is 46 mm,
30 sheets of 1.6mm thick steel sheet, same shape, 50mm modulus of 2.5mm thickness, 2.3kgf / c
31 soft plates made of a rubber material having a m ² , a tensile strength of 90 kgf / cm ² , and an elongation at break of 760% were used. Around a lead having a diameter of 20 mm and a height of 148 mm, a hollow portion was formed. FIG. 6 in which 99 protective rings made of 66 nylon having a diameter of 46 mm, an inner diameter of 20 mm, and a thickness of 1.5 mm are arranged.
6 sets of seismic isolation structures 16 as shown in FIG.
The book was fixed on a pile foundation, and a concrete support floor was fixed above the pile foundation, thereby constituting the seismic isolation ground of the present invention. A detached house with a load of 50t was built on this seismic isolation ground, and when ± 200% shear deformation was repeatedly applied to the seismic isolation ground 15 times, good seismic isolation performance was shown. It was confirmed that no cutting occurred and no buckling deformation of the base-isolated structure occurred.

FIG. 7 is a schematic sectional view of a base isolation structure 32 used for the base isolation ground according to the present invention.
6 is provided with a hollow portion in the center thereof, and a friction plate 34 made of glass fiber reinforced unsaturated polyester resin (hereinafter, simply referred to as FRP) is laminated and sealed in the hollow portion. I have. A holding plate 36 is arranged on the laminated body of the friction plates 34, and a holding bolt with a hexagonal hole having a female thread at the center is arranged as an upper pig 38.
To apply a sealing input to the friction plate 34 laminate.

Applying sealing pressure to a friction plate, a hard granular material, or the like inserted into the columnar hollow portion of the composite laminate by such a threaded upper pig can be performed by, for example, forming a columnar plastic material as shown in FIG. The present invention is effective for any shape including the one in which the protection ring is inserted.

Here, the friction plate used in the seismic isolation structure of the present invention will be described in detail. The material of the friction plate used in the present invention is not particularly limited, such as a polymer material, a metal, a ceramic, and an inorganic material. As the polymer material, specifically, for example, as a thermoplastic, polyamide (nylon), polyethylene, polypropylene, polystyrene,
Glass fiber reinforced polystyrene, poly-P-xylene, polyvinyl acetate, polyacrylate, polymethacrylate, polyvinyl chloride, polyvinylidene chloride, fluoroplastic, polyacrylonitrile, polyvinyl ether, polyvinyl ketone, polyether, polycarbonate, thermoplastic Polyester, diene-based plastic, polyurethane-based plastic, aromatic polyamide, polyphenylene, silicone, and the like can be used. Among them, nylon, polyethylene, polyester, polypropylene, polyvinyl chloride, thermosetting plastic, and the like are preferable from the viewpoint of material properties and availability. Further, FRP using the above-mentioned thermoplastic or thermosetting plastic as a matrix (for example, FRP of unsaturated polyester resin) or the like can also be used. These materials may be used alone or in combination of a plurality of types, and a plasticizer or a filler may be added.
A reinforcing material such as glass fiber or carbon fiber such as P may be mixed and used.

The diameter d of the friction plate of the present invention is preferably 0.1 ≦ (d / D) ≦ 0.8, where D is the diameter of the hard plate. More preferably, 0.1 ≦ (d / D) ≦ 0.6. When d / D exceeds 0.8, the frictional force becomes too large, the balance with the spring rigidity of the seismic isolation structure is lost, and the restoring force is impaired. If d / D is less than 0.1, the initial rigidity becomes insufficient, and it becomes impossible to prevent wind sway.

The friction plate of the present invention has a pushing force of 2 kg / cm ² to 200 kg / cm into a hole penetrating the composite laminate.
It is preferable to enclose in ² . More preferably, 10
100 kg / cm ² . 200kg pressure
If it exceeds / cm ² , the seismic isolation structure will be greatly elongated in the vertical direction, and the upper limit is 200 kg / cm ² even in consideration of the initial sinking amount during use, ie, during loading. If the pushing force is less than 2 kg / cm ² , the compressive force is insufficient, and a sufficient frictional force cannot be obtained as a seismic isolation structure.

The sealing force (pressing force) of the friction plate can be controlled by adjusting the tightening torque of a screw of a lid having a thread provided on the upper portion of the friction plate. That is, a screw is cut in the upper surface plate, a lid having a screw thread adapted to the screw is provided, and the sealing force applied to the friction plate is adjusted to be constant by making the screw tightening torque constant. The size of the screw is preferably the same as or smaller than the friction plate.

Here, the outer diameter is 250 mm, the inner diameter is 50 mm,
1. 30 sheets of 1.6 mm thick steel plate with similar shape and thickness
31 soft plates made of a rubber material of 5 mm, a 50% modulus of 2.3 kg / cm ² , a tensile strength of 90 kg / cm ² , and an elongation at break of 760% are used. A 49.8 mm, 1.5 mm thick friction plate made of 66 nylon is placed without gaps, and the pushing force is 15 k.
Using six sets of seismic isolation structures 32 as shown in FIG. 7 to which a compressive force was applied with an upper lid threaded at g / cm ² , each was fixed on six pile foundations, and A concrete housing support floor was fixed to form the seismic isolation ground of the present invention.
A detached house with a load of 50 tons was constructed on the seismic isolation ground, and ± 200% shear deformation was repeatedly applied to the seismic isolation ground 15 times, showing good seismic isolation performance. It was confirmed that buckling deformation did not occur in the structure.

FIG. 8 is a sectional view of a seismic isolation structure 40 that can be used for the seismic isolation ground of the present invention. The seismic isolation structure 40 includes the hard plate 2
A glass bead (spherical) 4 as a hard granular material is provided in a hollow portion provided at the center of a composite laminate 28 comprising
2 is filled while tapping, and a compressive force is applied to the upper part of the glass beads 42 by means of a threaded lid to fill and enclose the glass beads 42 in a compressed state. It is covered with a jacket rubber 44 made of a system rubber material.

The hard granular material filled in the columnar hollow portion of the seismic isolation structure can be compressed and filled to prevent excessive deformation of the seismic isolation structure due to frictional force between the granular materials. If so, there is no particular limitation, but preferable materials include, for example, copper, iron, sand for sandblasting, glass, quartz, plastic, and granular materials manufactured from natural or industrial wastes, and the like. Further, fiber-reinforced plastics, various ceramics, and the like having sufficient hardness can also be used.

The size of the granular material is preferably in the range of 0.01 to 30 mm. When the size is less than 0.01 mm, sufficient stress cannot be applied at the time of filling. The contact area is small, and it is difficult to obtain a desired frictional force.

Specific examples of the hard granular material include glass beads, metal balls such as iron balls and copper balls, sand, quartz powder, Al ₂ O
Sand blasting sand containing ₃ as a main component.

The shape of the granular material is not particularly limited as long as it has the above-mentioned size.
It may be any of irregular shapes and the like, and the surface of the granular material may be smooth or may have fine irregularities. Also, those having a shape close to a sphere having an aspect ratio of about 3 or less are preferably used.

When filling the hard granular material into the hollow portion of the seismic isolation structure, it is necessary that the hard granular material be filled in a close-packed manner, for example, by tapping, and then sealed with a lid or the like so that stress is applied. Is preferred. Since the frictional force between the hard particles closely packed in the hollow portion contributes to the damping effect, the desired damping effect cannot be obtained in the filled state having a space where the hard particles can freely vibrate with each other, which is preferable. Absent.

Here, the outer diameter is 250 mm, the inner diameter is 50 mm,
1. 30 sheets of 1.6 mm thick steel plate with similar shape and thickness
5%, 50% modulus is 2.3 kgf / cm ² ,
Tensile strength 90 kgf / cm ² , elongation at break 760
Using 31 soft plates made using a rubber material of
Fill the hollow portion with the maximum amount that can be filled while tapping glass beads with a diameter of 1 mm, apply a compressive force to the threaded lid with a torque of 15 kg / cm ² , and the glass beads inside are compressed. Using six sets of seismic isolation structures 40 filled and sealed as shown in FIG. 10, each of which is fixed on six pile foundations, and a concrete housing support floor is fixed on top of the pile foundations. The seismic isolation ground of the invention was constructed. A detached house having a load of 50 t was constructed on the seismic isolation ground, and ± 200% shear deformation was repeatedly applied to the seismic isolation ground fifteen times to show good seismic isolation performance.

In order to impart weather resistance to the base isolation ground of the present invention, the outside of the base isolation structure may be covered with a material having excellent weather resistance. As this coating material, for example, butyl rubber,
Acrylic rubber, polyurethane, silicone rubber, fluorine rubber, polysulfide rubber, ethylene propylene rubber (ERP and EPDM), chlorosulfonated polyethylene, chlorinated polyethylene, ethylene vinyl acetate rubber, chloroprene rubber, and the like can be used. These materials may be used alone or as a blend of two or more. Further, it may be blended with natural rubber, isoprene rubber, styrene-butadiene rubber, butadiene rubber, nitrile rubber and the like.

It is almost impossible to predict the magnitude of an earthquake at present, and an earthquake having a magnitude exceeding a design value may occur. In the case of such a huge earthquake, it is necessary to consider that even a seismic isolation structure having seismic isolation performance improving means therein may buckle due to large shear deformation. In order to cope with such a large shear deformation, it is considered effective to arrange a fail-safe for the base-isolated structure at the foundation. FIG. 9A is a perspective view showing a state in which a fail-safe 46 is provided on the pile head cap 20 of the pile foundation 14 constituting the foundation so as to surround the seismic isolation structure 16. FIG. 9 shows the fail safe 46.
As shown in (A), the seismic isolation structure 16 may be surrounded by 360 °, or may be 360 ° or less. For example, they may be arranged so as to surround 90 ° as shown in FIG.
° It may be arranged so as to surround it.

However, with respect to the height (L) of the laminated body including the flange of the seismic isolation structure 16, the height (l) of the fail-safe 46 naturally satisfies l <L. FIG. 9 (C)
FIG. 9 is a model diagram showing a state in which a large shear deformation has occurred in the seismic isolation ground of the present invention. FIG. 9 shows a case where a deformation exceeding a design value is applied to the seismic isolation structure 16 fixed to the base portion 14.
As shown by the broken line in (C), the housing support floor 18 fixed to the seismic isolation structure 16 rides on the fail-safe 46 and is designed to prevent the buckling deformation of the seismic isolation structure 16. Is done.

In the base-isolated ground of the present invention, a structure such as a house is supported, and the (b) house supporting floor connected to the (b) base-isolated structure has a strength necessary to support the structure. Required. In order to achieve such strength, it is useful that the (c) housing support floor in the present invention is assembled as an outer frame composed of a frame made of metal, concrete, or the like, for example, H steel, PC board, or the like. It is. FIG.
(A) is a perspective view showing one mode of the house support floor 18 composed of an outer frame 48 made of H steel used for the base-isolated ground of the present invention. As shown in FIG. 10B, the housing support floor 18 preferably has a structure including an inner frame 50 for improving strength in addition to an outer frame 48 made of H steel. If the inner frame 50 can achieve the required strength,
It may be H steel or a material made of another material or shape. In order to achieve the strength required to support a structure such as a house, a suitable number of the inner frames 50 can be arranged according to the purpose.

The portion of the housing support floor that is connected to the seismic isolation rubber is connected by bolts, and furthermore, the fail-safe 46 is contacted with the housing support floor to fully exert its performance. In the vicinity of the house supporting floor in contact with the seismic isolation structure, for example, a reinforcing plate 52 as shown in FIG.
It is preferable to provide The reinforcing plate 52 is made of a material such as metal, concrete, and ceramics, and is formed by being fixed to the housing support floor 18.

Further, in order to compensate for the decrease in seismic isolation performance due to the light weight of a lightly loaded structure such as a detached house, a plate member 54 is arranged below the housing support floor 18, and a uniform plate is placed on the plate member 54. Alternatively, an auxiliary load 56 having an arbitrary weight gradient can be applied. FIG. 10D is a perspective view showing a state in which an auxiliary load 56 is placed on a plate member 54 arranged below the housing support floor 18.

The auxiliary load 56 may be anything as long as it is inexpensive, for example, metal, concrete, sand,
Those with a large specific gravity such as gravel, soil, various waste materials and various natural materials are effective.

As described above, the base-isolated ground of the present invention has a base part for fixing to the ground, a base-isolated structure internally provided with means for improving seismic isolation performance, and a structure such as a house on the base-isolated structure. It consists of a house supporting floor for building a body and is connected to each other, so that it is possible to achieve excellent seismic isolation performance for light loads with a simple structure.

[0056]

As described above, the present invention has the above-mentioned structure, and can be suitably used for light-weight objects such as detached houses. It has high durability, has no plastic deformation or breakage, has excellent durability, and prevents traffic vibration. And the low-cost seismically isolated ground was obtained.

[Brief description of the drawings]

FIG. 1A is a schematic cross-sectional view showing one embodiment of the seismic isolation ground of the present invention, and FIG. 1B is a schematic cross-sectional view showing a state where a house is arranged above the seismic isolation ground.

FIG. 2 (A) shows a columnar pile used for a pile foundation of seismic isolation ground, (B) shows a pile head cap arranged at the pile head of the pile, and (C) shows a plurality of piles. One pile head cap 2
FIG. 2D is a schematic sectional view showing a hollow pile suitable as a pile foundation.

FIG. 3A is a schematic cross-sectional view showing a plate-shaped pile used as a pile foundation of a base-isolated ground, and FIG. 3B is a schematic sectional view showing a flat plate-shaped pile having a flange portion protruding in the ground direction around the pile. is there.

FIG. 4 (A) shows an example of the shape of a top frame used for base-isolated ground, FIG. 4 (B) shows a state where the top frame is connected to a plane, and FIG. It is the schematic which shows the state which used what was connected in the shape in two steps.

FIG. 5 is a schematic cross-sectional view showing a state in which a seismic isolation structure is connected to a top type foundation used as a pile foundation of the base isolation ground.

FIG. 6 is a schematic cross-sectional view showing a base-isolated structure used for the base-isolated ground of the present invention, in which lead is arranged in a hollow portion.

FIG. 7 is a schematic sectional view showing a seismic isolation structure used for the seismic isolation ground of the present invention, in which friction plates are stacked and arranged in a hollow portion.

FIG. 8 is a schematic sectional view showing a seismic isolation structure having a hollow portion filled with hard granular materials, which is used for the seismic isolation ground of the present invention.

FIG. 9A is a perspective view showing a state in which a fail-safe is arranged around a 360 ° seismic isolation structure on a pile head cap of a pile foundation, and FIG. 9B is a perspective view of the pile head cap of the pile foundation. It is a perspective view which shows the state which arrange | positioned the fail safe so that it might surround 90 degrees so that the seismic isolation structure may be shown above, (C)
FIG. 4 is a model diagram showing a fail-safe function when a large shear deformation occurs in the base-isolated ground.

FIG. 10 (A) shows an embodiment of a house supporting floor composed of an outer frame made of H steel used for seismic isolation ground, and FIG. 10 (B).
Shows a house supporting floor having a structure provided with an inner frame for improving strength in addition to an outer frame, (C) shows a house supporting floor having a reinforcing plate on an outer frame, and (D) shows a house supporting floor. It is a perspective view showing the state where the auxiliary load was put on the board arranged at the lower part of the floor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Seismic isolation ground 12 House (structure) 14 Pile foundation (foundation part) 16 Seismic isolation structure 18 House support floor 20 Pile head cap 24 Hard plate 26 Soft plate 28 Composite laminate 30 Lead (plastic) 34 Friction plate 42 Glass beads (hard granular material) 46 Fail safe

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location F16F 15/04 8919-3J F16F 15/04 A

Claims (7)

[Claims] 1. A base isolation base having a foundation, a base isolation structure, and a house support floor, wherein the base isolation structure is a rigid plate having rigidity and a soft plate having viscoelastic properties. And a plurality of columns, each having a columnar hollow portion penetrating the composite laminate, and a means for improving the seismic isolation characteristics of the composite laminate. A base-isolated ground characterized by the following. 2. The base-isolated ground according to claim 1, wherein the foundation is a pile foundation. 3. The seismic isolation ground according to claim 2, wherein a pile head cap is attached to the top of the pile used for the pile foundation. 4. The base-isolated ground according to claim 2, wherein said pile foundation is made of a plate-like pile. 5. The means for improving the seismic isolation characteristics of the composite laminate is selected from the group consisting of means for arranging a plastic material, means for laminating and filling friction plates, and means for filling hard particulate matter. The base-isolated ground according to claim 1, wherein: 6. The seismic isolation ground according to claim 1, wherein a fail safe for preventing large deformation of the seismic isolation structure is attached to a base portion of the seismic isolation ground. 7. The base-isolated ground according to claim 1, wherein the housing supporting floor is formed of a frame made of H steel, and an auxiliary load is placed in the frame.