JP2000345736A - Vibration isolation building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of rocking by forming a fixed angle of inclination on a horizontal plane to the extending direction of a building wall surface in the axial directions of each rail for a vibration isolation isolator vibration-isolating and bearing an upper structure. SOLUTION: An upper structure 10 is vibration-isolated and borne from the ground side by a vibration isolation device by orthogonal rail type vibration isolation isolators 30.... In the vibration isolation building, the axial directions of each rail for the vibration isolation isolators 30 are arranged so as to form the fixed angle of inclination on a horizontal plane to the extending direction of a building wall surface so as not to run parallel with the extending direction of the building wall surface. Accordingly, distances among an initial rail support and columns 13 for the upper structure 10 are made shorter than the axial directions of the rails run parallel with the building wall surface, and the distances are also shortened similarly in the case of vibration isolation in response to the shortening of the distances. Thus, the deflection of floor beams 11 in the case of vibration isolation is reduced, rocking is hard to generate, and the structural stability of the vibration isolation building can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base-isolated building, and more particularly to a base-isolated building such as a detached house.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. Hei 10 (1999) discloses a seismically isolated building whose upper structure is seismically isolated from the ground (foundation) side by a seismic isolation device.
As disclosed in JP-A-88849, as a seismic isolation device, a lower rail connected to the ground, an upper rail extending in a direction orthogonal to the lower rail and connected to an upper structure, An orthogonal rail-type seismic isolator consisting of a rigid structure center block (post) that slidably engages the lower rail and slidably engages the upper rail at the top. The seismic isolation building used is known.

A seismic isolation isolator of the orthogonal rail type is disclosed in Japanese Patent Application Laid-Open No. 60-111142 and Japanese Patent Application Laid-Open No. Hei 8-240033.
No. of materials, quenched area, light weight, compact, inexpensive, and easy to prevent lifting mechanism compared to the seismic isolator of the saucer type used in the seismic isolation building shown in It has the great advantage that it can be incorporated.

[0004]

However, when the ground side and the upper structure are displaced relative to each other, the center block between the upper rail and the lower rail moves on the rail surface in the horizontal direction, and the axial force of the building column is always constant. Since the load transmission axis moves while acting on the column base, the floor girder joined to the column base is bent as a cantilever from the rail center block engagement position. The movement of the center block changes the amount of deflection of the floor girders, and may cause rocking. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a seismic isolated building that uses an orthogonal rail type seismic isolator and that is improved so that rocking does not easily occur. It is an object.

[0005]

In order to achieve the above object, a seismic isolation building according to the first aspect of the present invention provides a seismic isolation device in which an upper structure is formed by a seismic isolation device using an orthogonal rail type seismic isolation isolator. In a seismically isolated building supported
An axial direction of each rail of the seismic isolation isolators is arranged so as to have a predetermined inclination angle in a horizontal plane with respect to the extending direction of the building wall surface so that the axial direction of each rail is not parallel to the extending direction of the building wall surface. According to this configuration, the distance between the initial rail column and the column of the upper structure is shorter than when the axial direction of the rail is parallel to the building wall surface, and accordingly, the rail column at the time of seismic isolation is used. The distance between the floor and the pillars is also reduced, and the deflection of the floor beams during seismic isolation is reduced, making rocking less likely to occur.

The seismic isolation building according to the invention of claim 2 is:
The axis direction of each rail of the seismic isolation isolators located at the corners and corners of the upper structure as a whole is predetermined on the horizontal plane with respect to the extending direction of the building wall so that the axial direction does not become parallel to the extending direction of the building wall Are arranged so as to have an inclination angle of. According to this configuration, the distance between the initial rail support, the corner of the upper structure, and the corner pillar is shorter than when the axial direction of the rail is parallel to the building wall surface. At the time of seismic isolation, the distance between the corner pillars and the corner rail supports and columns is also shortened, the floor beam deflection during seismic isolation is reduced, and rocking is less likely to occur.

[0007] The seismic isolation building according to the invention of claim 3 is:
At the corners and corners of the upper structure that is the installation part of the seismic isolation isolators, fire beams in the same direction are provided in the oblique extension direction of the rails on the upper structure side, and the rails on the upper structure side are fixed to the fire beams. Is what it is. According to this configuration, the corners and corners of the upper structure serving as the installation part of the seismic isolation isolators are provided, and the rail on the upper structure side is fixed to the blow beam.

[0008] The seismic isolation building according to the invention described in claim 4 is:
In a base-isolated building where the upper structure is seismically isolated from the ground side using a seismic isolation device with orthogonal rail-type seismic isolation isolators, the axial direction of each rail of the seismic isolation isolators should be at least two directions at a certain height. The seismic isolation isolators are located in the area. According to this configuration, even when vibration occurs, it becomes difficult for the rail support and the column base to separate from each other at the positions of the seismic isolation isolators, and locking can be prevented.

[0009]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 to 7 show an embodiment of a base-isolated building according to the present invention. In these figures, 10 indicates an upper structure, and 20 indicates a foundation on the ground. The upper structure 10 includes four steel-frame columns (column bases) each including a square-frame steel floor girder 11 and a square-frame steel girder ceiling girder 12 (only one is shown).
13A, 13A, 13A, 13A, etc., is a combination of a plurality of box-frame-structure building units rigidly connected to each other by welding or the like.

As shown in FIG. 1, in this method, the pillars 13a may be concentrated where the corners of the building units meet, and for convenience of explanation, the set of two to four pillars 13a is also formed. It is called pillar 13. The same applies to the floor girders 11 and the ceiling girders 12. Right below each column 13, an orthogonal rail type seismic isolation isolator 30 is installed as a seismic isolation device between the foundation 20 and a lower part of the middle of each floor girder 11 on the girder side connecting the adjacent columns 13. A laminated rubber 40 is installed as a seismic isolation device between the base and the base 20.

As shown in FIG. 5, the seismic isolation isolator 30 includes a lower rail 31 connected to the foundation 20,
The upper structure 1 extends in a direction orthogonal to the lower rail 31.
An upper rail 32 connected to the upper rail 32 and a rigid-structure center block 33 that slidably engages the lower rail 31 at the lower part and slidably engages the upper rail 32 at the upper part. It has a structure that maintains column base axial force support regardless of horizontal displacement during seismic isolation.

As shown in FIG. 2, among the seismic isolation isolators 30, those located at the four corners of the upper structure 10 as a whole have lower rails 31 and upper rails 32 whose axial directions are the same. The upper rail 32 is oriented in a direction parallel to a fire beam 16 to be described later, and the lower rail 31 is oriented in a direction orthogonal to the upper rail 32. 11 are arranged so as to have a 45-degree inclination angle in the horizontal plane with respect to the horizontal extending direction. The seismic isolation isolators 30 other than those located at the four corners are arranged so as to be parallel or orthogonal to the horizontal direction of the building wall and the floor girders 11.

As shown in FIGS. 4A to 4C, the laminated rubber 40 is composed of a rubber-like elastic body 41 having a high damping property, such as chloroprene rubber, acrim rubber, or silicone rubber, and an iron plate 42 alternately. The secondary shape factor is 3 or less, and the vibration frequency obtained from the vertical spring constant at the time of no deformation and the mass of the upper structure 10 is equal to the secondary characteristic of the floor beam (floor beam 11). Higher than the frequency, FIG. 4 (a)
As shown in FIG. 5, only when the relative horizontal displacement between the foundation 20 and the upper structure 10 can be regarded as substantially zero, the upper structure 1
As shown in FIGS. 4 (b) and 4 (c), the structure has a structure that elastically deforms in the shearing direction at the time of relative displacement to give the load to the floor girder 11, for example. ,
The load from the floor and the columns is applied to the floor girders 11, but the laminated rubber normally functions to prevent deflection and vibration of the floor girders 11.

The laminated rubber 40 is installed at a position corresponding to the antinode of the primary or secondary natural vibration mode of the floor beam. The installation position of the laminated rubber 40 may be set according to the span of the column adjacent on the girder surface, and the column span is about 4 to 5 m as shown by reference numerals La and Lb in FIG. If there is, it will be at one place at the center of the half of the floor girder 11, and if it is about 6 m or more as indicated by the symbol Lc, it will be at two places at the center 1/3 of the floor girder 11, and It will have a seismic isolation device.

The laminated rubber 40 has flange plates 43 and 4 at both ends.
The upper flange plate 43 is connected to the floor girders 11 of the upper structure 10 by bolts or the like, and the lower flange plate 44 is not fastened via the foundation 20. In this case, the coefficient of friction of the joining surface between the non-fastened side flange plate 44 and the foundation 20 is the horizontal rigidity of the laminated rubber generated at the time of the relative displacement at which the horizontal rigidity and damping of the laminated rubber 40 exhibit the normal performance. Both are set to values that cause slip displacement. The horizontal rigidity of the laminated rubber 40 can be set such that the distance (eccentric distance) between the center of gravity and the center of rigidity of the upper structure 10 is substantially zero.

As shown in FIGS. 6 and 7, the floor girders 11 on the first floor of the upper structure 10 correspond to the positions where the seismic isolation isolators 30 are arranged.
L-shaped reinforced base 14 and I-shaped reinforced base 15 made of H-shaped steel or the like are provided underneath. The positions of the L-shaped reinforcement frames 14 are four corners and four corners when viewed in the upper structure 10 as a whole, and correspond to two orthogonal floor girders 11 and 11. The arrangement positions 15 correspond to the joint portions of the building units.

At the four corners of the upper structure 10 as a whole, there are fire struts in the same direction as the extending direction of the upper rail 32 corresponding to the 45-degree inclined arrangement of the seismic isolation isolators 30 at the four corners. An upper rail 32, which is a rail on the upper structure side, is fixed to the fire beam 16. The L-shaped reinforced base 14, the I-shaped reinforced base 15, and the battering beam 16 are attached to the floor girders 11 by welding or the like in the factory production process of the building unit having the box ramen structure, and are fixed in advance to the box ramen structure of the building unit. It is transported to the construction site in a state where it has been set. If it cannot be fixed in advance due to transportation restrictions, it is transported and installed separately from the structure.

As described above, the orthogonal rail type seismic isolation isolator 30 is installed at the position below the column base.
Regardless of the horizontal displacement at the time of seismic isolation, the column base axial force is effectively supported at the position below the column base, and the laminated rubber 40 is installed at the position below the floor beam. 4 (a)
As shown in FIG. 5, only when the relative horizontal displacement between the foundation 20 and the upper structure 10 can be regarded as substantially zero,
As shown in FIGS. 4B and 4C, the floor beam is elastically deformed in the shearing direction at the time of relative displacement, so that the floor beam can bear the load.

With the above-described load supporting structure, the laminated rubber 40 supports only a normal long-term load,
From this, the horizontal rigidity of the laminated rubber 40 can be set low by setting the secondary shape factor of the laminated rubber 40 to 3 or less, and a high-performance seismic isolation bearing can be realized even in a lightweight detached house. An inexpensive restoring damper can be realized, and a restoring force can be applied to the vibration damping effect and the relative displacement between the upper structure 10 and the foundation 20. In addition, since the laminated rubber 40 is made of a rubbery elastic body having a high damping property, such as chloroprene rubber, acrim rubber, and silicone rubber, a high damping property can be obtained, and the comfort can be improved.

Further, the laminated rubber 40 is installed at a position corresponding to the antinode of the primary or secondary natural vibration mode of the floor beam, and the vertical spring constant of the laminated rubber 40 is higher than the secondary natural frequency of the floor beam. Therefore, the primary or secondary natural vibration of the floor beam is effectively attenuated by the laminated rubber 40 having high vertical rigidity, and the traffic vibration from the outside and the floor vibration during the first floor walking are effectively attenuated. The livability is greatly improved, and the laminated rubber 40
However, no resonance phenomenon occurs due to floor vibration.

The laminated rubber 40 is connected to the upper structure 10 by fastening, but is not fastened to the foundation 20, and the friction coefficient of the joint surface between the laminated rubber 40 and the foundation 20 on the non-fastened side is: The horizontal stiffness and damping of the laminated rubber 40 are set to a value at which the sliding displacement occurs due to the horizontal stiffness of the laminated rubber 40 that occurs at the limit of relative displacement at which the performance is normally performed. When the horizontal displacement between the body 10 and the ground side is not large, as shown in FIG. 4B, the laminated rubber is formed by the frictional resistance of the joint surface between the non-fastened side laminated rubber 40 and the foundation 20. The laminated rubber 40 is elastically deformed in the shearing direction without the displacement of the laminated rubber 40 with respect to the foundation 20, and a restoration damping effect is obtained. If the horizontal displacement between the upper structure 10 and the ground side is large, such as when a moderate to large earthquake occurs, FIG.
As shown in (c), the laminated rubber is displaced on the non-fastened side with respect to the foundation 20 on the ground side, and the laminated rubber 40 is prevented from being displaced in the shearing direction beyond the limit shearing direction displacement. The durability of the rubber 40 does not decrease or breakage occurs, and the safety is maintained at a high level.

Among the seismic isolation isolators 30, those located at the four corners when viewed in the upper structure 10 as a whole are the lower rail 3
1. The axial direction of each rail of the upper rail 32 is not parallel to the building wall surface and the horizontal extending direction of the floor girders 11,
Since it is arranged so as to have a 45-degree inclination angle in the horizontal plane with respect to the horizontal extending direction of the floor girders 11, as shown in FIG. The distance between the initial rail support (center block 33) and the column 13 is shorter than when the building is parallel to the building wall, and the distance between the rail support (center block 33) and the column 13 during seismic isolation is accordingly reduced. And the deflection of floor beams during seismic isolation is reduced, locking is less likely to occur, and structural safety is improved.

An L-shaped reinforcing frame 14 and an I-shaped reinforcing frame 15 are provided at positions on the floor girders 11 on the first floor of the upper structure 10 that correspond to the positions where the seismic isolation isolators 30 are arranged. The fire struts 16 are attached in the same direction in the extending direction of the upper rail 32 in correspondence with the 45-degree inclined arrangement of the seismic isolation isolators 30 at the four corners of the four corners of the upper structure 10 as a whole. The floor rigidity of the first floor of the bearing building is effectively improved.

The L-shaped reinforcing frame 14, the I-shaped reinforcing frame 15, and the fire beam 16 are attached to the floor girders 11 by welding or the like in the factory production process of the housing unit having the box-frame structure, and are attached to the box-frame structure of the housing unit. Since it is transported to the construction site in a fixed state in advance, welding work at the construction site becomes unnecessary, shortening the construction time, transportation cost, construction cost is reduced, and because it is factory assembled,
The mounting position accuracy is stable and improved compared to the construction site.

The position of the seismic isolation isolators 30 arranged at an inclination angle of 45 degrees differs according to the overall outer shape of the upper structure 10, and as shown in FIG. In a building having a seismic isolator, not only the four corners but also the seismic isolation isolators 30 at the L-shaped corners of the projecting part are arranged at an inclination angle of 45 degrees. In the building as shown in FIG. 9, among the floor girders 11 on the first floor of the upper structure 10,
At a position corresponding to the position where each seismic isolation isolator 30 is arranged, an L-shaped reinforcing frame 14 and an I-shaped reinforcing frame 15 are provided.
Also, a T-shaped reinforcement base can be used if necessary.

In the above-described embodiment, the seismic isolation device installed at the position below the pedestal is the orthogonal rail type seismic isolation isolator 30, but the present invention is not limited to this, and is installed at the position below the pedestal. The seismic isolation device only needs to satisfy the condition of maintaining the column base axial force support regardless of the horizontal displacement at the time of seismic isolation. This includes a sliding bearing type seismic isolation device other than the orthogonal rail type, rolling There is a bearing-type seismic isolation device, a highly stable laminated rubber having a secondary shape factor of about 3 to 5, or the like, and these may be used.

[0027]

As will be understood from the above description, according to the seismic isolation building according to the first aspect of the invention, the upper structure is isolated from the ground side by the seismic isolation device using the orthogonal rail type seismic isolation isolators. In a supported base-isolated building, the axis direction of each rail of the base-isolator is not parallel to the extending direction of the building wall, and has a predetermined inclination angle in the horizontal plane with respect to the extending direction of the building wall. The distance between the initial rail support and the upper structure column is shorter than when the rail axis is parallel to the building wall, so the In addition, the distance between the rail supports and the pillars is shortened, the floor beam deflection during seismic isolation is reduced, locking is less likely to occur, and the structural stability of the seismic isolated building is improved.

According to the seismic isolation building of the second aspect of the present invention, the axial direction of each rail of the seismic isolation isolator located at the corners and corners of the entire upper structure is the extending direction of the wall surface of the building. In order not to be parallel, it was arranged so as to have a predetermined inclination angle in the horizontal plane with respect to the extending direction of the building wall, so compared to the case where the axis direction of the rail is parallel to the building wall, The corners of the initial rail support and superstructure,
The distance between the corner pillars is reduced, and the distance between the corner pillars and the corner rail supports and the columns at the time of seismic isolation is shortened accordingly, the deflection of the floor beams at the time of seismic isolation is reduced, and locking does not easily occur. Therefore, the structural stability of the base-isolated building is improved.

According to the base-isolated building according to the third aspect of the present invention, the corners and corners of the upper structure serving as the installation part of the seismic isolation isolators are in the same direction as the inclined extending direction of the rail on the upper structure side. And the rails on the upper structure side are fixed to the fire beams, so that the floor rigidity is improved, and the seismic isolation isolators are attached to the upper structure side rationally. The entire seismic isolation isolators can be housed in the lower part of the structure without damaging the appearance of the building. According to the seismic isolation building of the fourth aspect of the present invention, the seismic isolation isolators are arranged so that the axial direction of each rail of the seismic isolation isolator is at least two directions at a certain height. Even in the case where it occurs, it becomes difficult for the center block engaging position and the column base to separate at the same time at all the positions of the seismic isolation isolators, and locking can be prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part showing one embodiment of a base-isolated building according to the present invention.

FIG. 2 is a floor plan showing an arrangement of seismic isolation isolators at four corners of a seismic isolation building according to the present invention.

FIG. 3 is a girder view showing an arrangement position of a seismic isolation device in a seismic isolation building according to the present invention.

4 (a) to 4 (c) are elevation views showing an operation state of a laminated rubber in a base-isolated building according to the present invention.

FIG. 5 is a perspective view showing an example of an orthogonal rail type seismic isolation isolator used in the seismic isolation building according to the present invention.

FIG. 6 is a floor plan of the first floor showing an arrangement of fire beams of the base-isolated building according to the present invention.

FIG. 7 is a perspective view showing an arrangement of a fire beam and a reinforcing frame of the base-isolated building according to the present invention.

FIG. 8 is an explanatory diagram showing the operation of an orthogonal rail type seismic isolation isolator arranged at a corner of a building.

FIG. 9 is a floor plan of the first floor showing another embodiment of the base-isolated building according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Upper structure 11 Floor girder 12 Ceiling girder 13 Column 14 L-shaped reinforcement base 15 I-shaped reinforcement base 16 Fire beam 20 Foundation 30 Seismic isolation isolator 31 Lower rail 32 Upper rail 33 Center block 40 Laminated rubber 41 Rubber elastic body 42 Iron plate 43, 44 Flange plate

Claims (4)

[Claims] In a seismic isolation building in which an upper structure is seismically isolated from the ground side by a seismic isolation device using an orthogonal rail type seismic isolation isolator, the axial direction of each rail of the seismic isolation isolator is equal to the length of the building wall. A seismic isolation building characterized by being arranged so as to have a predetermined inclination angle on a horizontal plane with respect to an extending direction of a building wall surface so as not to be parallel to the direction. 2. An axial direction of each rail of the seismic isolation isolator located at a corner or a corner of the entire upper structure so as not to be parallel to an extending direction of the building wall. The seismic isolation building according to claim 1, wherein the building is arranged so as to have a predetermined inclination angle in a horizontal plane. 3. A fire beam in the same direction as the rail extending on the upper structure side is provided at a corner and a corner of the upper structure serving as an installation part of the seismic isolation isolators. The seismic isolation building according to claim 2, wherein the rail is fixed. 4. A seismic isolation building in which the upper structure is seismically isolated from the ground side by a seismic isolation device using orthogonal rail type seismic isolation isolators, wherein the axial direction of each rail of the seismic isolation isolators is at least at a certain height. A seismic isolation building characterized by placing seismic isolation isolators in two directions.