JP2001295501A - Base isolation frame - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base isolating frame which allows floating of a building, when rocking vibrations are caused by earthquakes, reduces seismic inputs by utilizing the floating, can adjust the occurrence of the floating over a wide range, and can satisfactorily secure the stability and vibration isolating performance of the building under all design conditions. SOLUTION: In this base isolation frame, in which a building is isolated floatably from a foundation structure, such as bearing ground, footing piles, etc., the building and structure are connected to each other via a cable housed in a sleeve pipe laid via the bearing point between the building and structure and both ends of the cable are fixed to the building side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a base-isolated structural frame such as a building, which allows lifting due to rocking vibration during an earthquake, and reduces the earthquake input using the lifting.

[0002]

2. Description of the Related Art Conventionally, as a technique of a base-isolated structure of a building having a large aspect ratio (ratio of height to width), for example, techniques disclosed in Japanese Utility Model Publication No. 6-18996 and Japanese Patent No. 631486 are disclosed. It is known. These seismic isolation structures are based on a structure in which a building and a supporting plate (foundation structure) are tied up and down, and rigidly restrain the building from rising due to rocking vibration during an earthquake. Similarly, this is a technique for reducing the earthquake input acting on the building by relatively displacing the building in the horizontal direction.

On the other hand, as shown in FIG.
As in the invention described in the specification of Japanese Patent Application No. 1-42759 (hereinafter simply referred to as the invention of Japanese Patent Application No. 11-42759), a boundary between a building 1 having a large aspect ratio and a support plate (base structure) 2 is cut off. Thus, contrary to the above-described conventionally known seismic isolation structure frame, the building 1 is allowed to lift due to rocking vibration during an earthquake, and the building 1 is used by the relative displacement in the vertical direction by using the lift. A groundbreaking technology has been proposed to reduce the earthquake input acting on tsunami.

[0004]

[Problems to be solved by the present invention]
The seismic isolation frame of the 2759 invention is generally configured so that the building 1 does not fall due to the scale effect. At the same time, the generation of the building 1 during the earthquake (the amount of lifting and the period of the lifting) is adjusted. The distance L between the support points (concavities and convexities) 3, 3 between the support plate 1 and the support plate (foundation structure) 2 is set to ensure a good balance between the stability of the building 1 and the seismic isolation performance. ing.

In other words, in order to increase the amount of lift of the building 1 and to shorten the period of the lift, the distance L between the support points (concavo-convex portions) 3, 3 is reduced and the aspect ratio of the building 1 is increased. What is necessary is just to make it a suitable support state. For example, this adjustment is effective when improving the seismic isolation performance of a building having a heavy underground floor.

On the other hand, in order to adjust the lifting amount to be small and the lifting period to be long, it is necessary to use support points (uneven portions).
What is necessary is just to make the space | interval L of 3 and 3 large, and to set it as the support state similar to the case where the aspect ratio of the building 1 is small. For example, the adjustment is effective when improving the stability of a building having no basement floor. However, in this case, since the interval L between the support points (concavo-convex portions) 3 and 3 cannot be made larger than the width of the bottom surface of the building 1, necessary adjustment may not be performed.

Therefore, a building 1 and a support plate (foundation structure) 2
May be connected by an auxiliary member or the like, and a necessary reaction force may be exerted between the two members via the same member or the like in the event of an earthquake. However, for example, a technique of connecting a building and a support plate in a pretension state with a rope-shaped or rod-shaped tensile material disclosed in Japanese Patent Application Laid-Open No. 10-317713, and Japanese Patent Application Laid-Open No. 11-311.
In order to apply the technology disclosed in Japanese Patent Publication No. 038 for connecting a building and a foundation pile with a prestressed cable,
These techniques are intended for the above-mentioned conventionally known seismic isolation frames based on a structure in which a building and a foundation structure such as a support plate and a foundation pile are connected in the vertical direction. Furthermore, since these technologies have a structure in which the reaction force that resists the lifting of the building is largely borne by the supporting structure or the foundation structure such as foundation piles as the resistance to the pullout force of the tensile material or the cable, the foundation structure is used for this purpose. Construction is required to have a high strength that can be endured, and the construction becomes complicated, and the cost increases accordingly.

As an embodiment in which the seismic isolation frame of the invention of Japanese Patent Application No. 11-42759 is broadly applied,
As shown in an example in FIG. 8, it is conceivable that the building 1 having a large aspect ratio is vertically cut off at the middle floor and seismically isolated. Also in this case, in order to ensure a good balance between the stability of the building 1 and the seismic isolation performance, the upper floor portion 1 of the building 1 is used.
The problem is how to properly adjust the occurrence of the lift (lift amount and lift cycle) between A and the lower floor portion 1B under various design conditions.

It is also conceivable to cut off the seismic elements such as earthquake-resistant walls and braces constituting the building and the building frame (columns, beams, etc. inside the building) to make them seismic isolated. Again,
The challenge is how to properly adjust the occurrence (lift amount and lift cycle) of the rise between the seismic element and the building frame under various design conditions.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to allow a lift, particularly a rocking vibration caused by an earthquake, to reduce an earthquake input by utilizing the lift, and to cut off the support of a building having a large aspect ratio. Occurrence between the building and the foundation structure such as plates and foundation piles, or between the upper and lower floors of the building, or between the seismic elements such as earthquake-resistant walls and braces constituting the building and the building frame (Lift amount and lift period) can be adjusted in a wide range, and the balance between the stability of the building and the seismic isolation performance can be secured well under any design conditions, and the construction is easy and economical. To provide a seismic frame.

[0011]

As a means for solving the above-mentioned problems, a seismic isolation structure according to the first aspect of the present invention is a method for mounting a structure between a building and a foundation structure such as a support plate or a foundation pile. In a base-isolated structure frame that is cut off so that it can be lifted, the building and the foundation structure are connected by a cable built in a sleeve tube that passes through a support point between the two, and both ends of the cable are connected to the building at both ends. It is fixed to the side.

According to a second aspect of the present invention, there is provided a seismic isolation structure frame in which a building is vertically separated so as to be lifted up on an intermediate floor, wherein an upper floor portion and a lower floor portion of the building are located between the two floors. Are connected by a cable built in the sleeve tube passing through the support point, and both ends of the cable are fixed to either one of the upper floor portion and the lower floor portion.

According to a third aspect of the present invention, there is provided a seismic isolation structure frame in which a seismic element such as an earthquake-resistant wall or a brace constituting the building and a building frame are cut off so as to be lifted. The element and the building frame are connected by a cable built in a sleeve tube that passes through a support point between the two, and both ends of the cable are fixed to the seismic element side.

According to a fourth aspect of the present invention, in the seismic isolation structure according to any one of the first to third aspects, an energy absorbing mechanism is provided at at least one fixing end of the cable. I do.

According to a fifth aspect of the present invention, in the seismic isolation structure according to any one of the first to fourth aspects, a prestress is introduced into the cable.

According to a sixth aspect of the present invention, in the seismic isolation structure frame according to any one of the first to fifth aspects, a viscoelastic body is sealed between the sleeve tube and a built-in cable. It is characterized by being.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The seismic isolation frame according to the first to sixth aspects of the present invention will be described with reference to FIGS.

FIG. 1 shows an embodiment of the invention as claimed in claim 1, wherein the invention is applied to a base-isolated structure frame in which a space between (a whole of) a building 1 and a support plate (foundation structure) 2 is cut off so as to be lifted. ing.

That is, the cut-off building 1 and the supporting plate (substructure) 2 are connected to each other by the cable 5 built in the sleeve tube 4 which continuously passes through the two supporting points 3 between the two. Both ends 5a, 5a of the cable 5 are fixed to the inside of a pillar (or an outer peripheral wall or the like) of the building 1, respectively.

In this embodiment, the fixing end 5 of the cable 5
a and 5a, as shown in FIG. 2, an energy absorbing mechanism 6 is provided. When a seismic force within the assumed range acts on the building 1, the structure is elastically deformed, and a large seismic force outside the assumed range is generated. When acting on the building 1, the energy absorbing mechanism 6
Is plastically deformed, so that excessive tension does not act on the cable 5, and no unreasonable reaction force acts on columns (or outer peripheral walls, etc.) of the building 1 (the invention according to claim 4). As the energy absorbing mechanism 6, for example, an elasto-plastic damper made of lead, low-yield-point steel, or the like is preferably used, but is not limited to this, and any material having the same elasto-plastic property may be used. The energy absorbing mechanism 6 includes a fixing end 5a, 5
If it is provided in at least one of a, the function is achieved.

In addition, if an appropriate prestress is introduced into the cable 5, the lifting period of the building 1 can be adjusted in a wider range (the invention according to claim 5). Details will be described later with reference to FIGS.

As further illustrated in FIG. 2, a viscoelastic body 7 is provided between the sleeve tube 4 and the built-in cable 5.
Is sealed, whereby the impact force between the building 1 and the supporting plate (foundation structure) 2 caused by the rising of the building 1 at the time of the earthquake is reduced (the invention according to claim 6).

In the present invention, the occurrence of the lifting of the building 1 (the lifting amount and the lifting period) is performed by connecting the building 1 and the substructure 2 in addition to the conventional adjustment by the distance L between the support points 3 and 3. The adjustment is also performed by the function of the cable 5. FIG. 3 shows a state in which seismic force acts on the building 1 in the embodiment of FIG. 1 to cause lifting due to rocking vibration. FIG. 4 shows the amount of lifting of the building 1 and the tension of the cable 5 at this time. 5 is a graph showing the relationship of FIG. The principle of the present invention will be described with reference to these drawings.

That is, when a tension exceeding the prestress A introduced by the seismic force acting on the building 1 is applied to the cable 5, the building 1 is lifted by rocking vibration as indicated by an arrow. That is, the rising cycle of the building 1 can be adjusted by the set value A of the prestress. Since the cable 5 is in a state in which it can move freely within the sleeve tube 4 to some extent, the reaction force of the cable 5 that resists the rising of the building 1 is mainly caused by both ends 5a and 5a.
Works on the building 1 itself (column or outer peripheral wall), and the amount of lift of the building 1 can be adjusted by this reaction force. However, the graph of FIG. 4 assumes that a seismic force acts on which the tension of the cable 5 becomes equal to or less than the value of B.

If a large seismic force outside the expected range acts,
Even when an excessive tension exceeding the value B is applied to the cable 5, the energy absorbing mechanism 6 is plastically deformed, so that no excessive tension is applied to the cable 5. Therefore, the building 1 where the ends 5a, 5a of the cable 5 are fixed.
Can be constructed with ordinary strength.

In this embodiment, even if the energy absorbing mechanism 6 is plastically deformed as described above, the energy absorbing mechanism 6 is provided on the building 1 side, so that it can be easily replaced. Even in the event that even the cable 5 is plastically deformed, the cable 5 can be pulled out and replaced after the viscoelastic body 7 has been sucked and collected from the sleeve tube 4.

In the embodiment shown in FIG. 1, the support plate 2 is used as the foundation structure. However, the foundation pile is used as the foundation structure, and the pile head of the foundation pile is inserted into the recess provided on the bottom of the building (direct foundation). It may be carried out in a form of being fitted and supported (not shown).

Next, FIG. 5 shows an embodiment of the invention as claimed in claim 2, in which the building 1 is applied to a base-isolated structure frame which is divided into an upper floor portion 1A and a lower floor portion 1B so as to be able to lift up on an intermediate floor. The form is shown.

In this embodiment, the upper floor portion 1A and the lower floor portion 1B of the cut off building 1 have the cable built in the sleeve tube 4 continuously passed through the support points 3 between them. 5 and both ends 5 of the cable 5
a, 5a are fixed inside the pillar (or the outer peripheral wall or the like) of the upper floor portion 1A. The basic principle is the same as that of the embodiment shown in FIG. The details of the ends 5a, 5a of the cable 5 can also be implemented as illustrated in FIG. However, in this case, it is also possible to implement the embodiment in which both ends 5a, 5a of the cable 5 are fixed to the lower floor portion 1B side (not shown).

Next, FIG. 6 shows a claim applied to a base-isolated structural frame in which the space between a seismic wall 1a, which is a seismic element constituting the building 1, and a girder (building body) 1b below the seismic wall 1a is cut off. An embodiment of the invention described in Item 3 is shown.

That is, the space between the two shear walls 1a and the lower girder (building frame) 1b of the cut-off building 1 is in the vicinity of the periphery of the bottom surface of the earthquake resistant wall 1a (the support which causes the rising of the earthquake resistant wall 1a). (Points) 3, 3 are connected by a cable 5 built in a sleeve tube 4 continuously passed through, and both ends 5a, 5a of the cable 5 are fixed to the side surface of the earthquake-resistant wall 1a. In this case, the earthquake-resistant wall 1a which is also an earthquake-resistant element
In this configuration, it is possible to adjust the occurrence of the lift (the lift amount and the lift cycle) between the first beam and the girder (building body) 1b based on the same principle as that of the embodiment of FIG.

Although illustration is omitted, the present invention can be applied to a brace and other seismic elements in the same manner as the embodiment shown in FIG.

In addition, the fixing ends 5a, 5a of the cable 5
Without the energy absorbing mechanism 6 and without introducing prestress into the cable 5, in a loosened state, between the building and the foundation structure such as the support plate and foundation pile, or the upper floor of the building Even the simplest configuration, such as connecting the part and the lower floor part, or connecting the building frame with the earthquake-resistant elements such as the earthquake-resistant walls and braces that make up the building, and mainly limiting only the amount of lift between the two Can be implemented.

[0034]

According to the seismic isolation structure according to the first to sixth aspects of the present invention, floating up due to rocking vibration during an earthquake is particularly allowed, and seismic input is reduced by using this floating up. In buildings with a large aspect ratio, the margins are cut off between the entire building and the foundation structure such as support plates and foundation piles, or between the upper and lower floors of the building, or the earthquake-resistant walls that compose the building・ Because it is possible to adjust the occurrence of the lift (lift amount and lift cycle) between the seismic elements such as braces and the building frame in a wide range, the balance between the stability of the building and the seismic isolation performance can be adjusted under any design conditions. Can be secured well. Moreover, the seismic isolation structure of the present invention is easy to construct and can be implemented economically.

[Brief description of the drawings]

FIG. 1 is an elevation view showing one embodiment of a seismic isolation structure frame according to the present invention.

FIG. 2 is an enlarged view showing details of a fixing end of a cable.

FIG. 3 is a diagram showing a floating state due to rocking vibration of a building during an earthquake in the embodiment of FIG. 1;

FIG. 4 is a graph showing a relationship between a lift amount of a building and a tension of a cable during an earthquake in a base-isolated structure frame according to the present invention.

FIG. 5 is an elevation view showing a different embodiment of the base isolation frame according to the present invention.

FIG. 6 is an elevation view showing a different embodiment of a base isolation frame according to the present invention.

FIG. 7 is an elevation view showing a conventional seismic isolation structure frame.

FIG. 8 is an elevational view showing a different conventional seismic isolation frame.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Building 2 Support plate (foundation structure) 3 Support point 4 Sleeve tube 5 Cable 5a Cable end (fixed end) 6 Energy absorption mechanism 7 Viscoelastic body 1A Upper floor part of building 1B Lower floor part of building 1a Seismic resistance Walls (seismic elements) 1b Girders (building frame)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuhiro Kasuga 1-5-1, Otsuka, Inzai City, Chiba Prefecture Inside the Takenaka Corporation Technical Research Institute (72) Inventor Soichi Kitani 4-chome Honmachi, Chuo-ku, Osaka-shi, Osaka No. 1-13 Takenaka Corporation Osaka Main Store (72) Inventor Tomoyuki Sagami 8-21-1, Ginza, Chuo-ku, Tokyo Inside Tokyo Takenaka Corporation Tokyo Main Store 8-21-1, Ginza-ku, Tokyo Takenaka Corporation Tokyo Main Store (72) Inventor Gen Taniguchi 1-5-1, Otsuka, Inzai City, Chiba Pref.

Claims (6)

[Claims] 1. A seismic isolation structure in which a building and a base structure such as a support plate and a foundation pile are cut off so as to be lifted, wherein the building and the base structure are connected via a support point therebetween. A seismic isolation frame, characterized by being connected by a cable built in a sleeve tube that has passed through, and both ends of the cable being fixed to the building side. 2. A seismic isolation structure frame in which a building is vertically separated so that it can be lifted up on an intermediate floor, wherein an upper floor portion and a lower floor portion of the building pass through a sleeve pipe passing through a support point therebetween. A seismic isolation frame, wherein the frames are connected by a built-in cable, and both ends of the cable are fixed to one of an upper floor portion and a lower floor portion. 3. A seismic isolation structure in which a seismic element such as a seismic wall or a brace constituting a building and a building frame are cut off so as to be lifted up, wherein the seismic element and the building frame form a support point therebetween. Connected by a cable built into the sleeve tube passed through,
A seismic isolation frame, wherein both ends of the cable are fixed to the seismic element side. 4. An energy absorbing mechanism is provided at at least one fixing end of the cable.
The seismic isolation structure frame according to claim 1. 5. The seismic isolation frame according to claim 1, wherein a prestress is introduced into the cable. 6. A viscoelastic body is sealed between the sleeve tube and a built-in cable inside the sleeve tube.
The seismic isolation structure frame according to any one of claims 1 to 5.