JP3827490B2 - Seismic isolation structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of a seismic isolation structure that is often found in buildings with a large aspect ratio and that allows for the lifting that occurs during an earthquake to reduce seismic force and ensure safety against falls and drop impacts.
[0002]
[Prior art]
The conventional general seismic isolation building 1 ′ is based on the idea of allowing large displacement in the horizontal direction in the seismic isolation layer as shown in FIG. 1A.
However, as shown in FIG. 1B, the base-isolated building 1 having a large ratio between the height and width (aspect ratio) of the building is dominated by rocking vibration including displacement in the vertical direction. Force acts. Therefore, there is a need for a seismic isolation device and a foundation that can withstand the large tensile axial force.
[0003]
Conventionally, a seismic isolation structure that allows a lift generated during an earthquake, secures safety against a fall of the structure and a drop impact, and reduces seismic force acting on the structure is disclosed in, for example, Japanese Patent Laid-Open No. 10-195890. And Japanese Patent Application No. 11-42759 of the present applicant and the drawings.
[0004]
[Problems to be solved by the present invention]
However, if the edge of the building and the foundation is cut and a large lift occurs during an earthquake, the energy is absorbed when the building is lifted. The seismic isolation structure has not been observed yet.
[0005]
An object of the present invention is to provide a seismic isolation structure of a reinforced concrete structure (hereinafter sometimes abbreviated as an RC structure) that allows the lift generated in the structure during an earthquake to be reduced and reduces the seismic energy.
[0006]
The object of the present invention is to reduce the seismic force by permitting the lift that occurs during an earthquake, to prevent the fall by limiting the lift amount, and also to reduce the shock caused by the structure. It is to provide an RC structure with seismic isolation structure.
[0007]
A further object of the present invention is that when an existing building is rebuilt, the following existing foundation and existing frame are left from the rising boundary surface, and a new RC structure is constructed on the RC structure. To provide seismic isolation structures.
[0008]
[Means for Solving the Problems]
As a means for solving the above-mentioned problem, the seismic isolation structure according to the invention described in claim 1 is:
In the seismic isolation structure, which is reinforced concrete structure, allows for the lifting that occurs at the time of an earthquake and reduces the seismic force, ensuring the safety of the structure to fall, drop impact,
The upper and lower pillars 5 and 6 of the structure and the lower pillar 5 ' and the beam 7 are cut off to form a floating boundary surface K ;
On the raised floor K of the lower floor and the beam, horizontal shearing force transmission protrusions 9 and 10 integrated with the lower floor pillar 5 ' and the beam 7 are raised,
A protrusion cover 12 having a downward concave portion into which the horizontal shearing force transmission protrusions 9 and 10 are fitted is installed at the lower ends of the upper floor pillar 5 and the wall 6 ;
The horizontal shear force transmitting projections 9, 10 is the recess 11 of the projection cover 12 is fitted to the mating gap therebetween, gelled highly viscous viscoelastic body is installed as an energy absorbing device 14 when lifting It is characterized by each.
[0009]
The invention according to claim 2 is the seismic isolation structure according to claim 1,
The raised boundary surface K of the lower-layer pillar 5 ′ and the beam 7 and the protrusion cover 12 installed at the lower ends of the upper-layer pillar 5 and the wall 6 are in direct surface contact, or a shock absorber such as a rubber sheet. The protrusion cover 12 is fixed to the lower ends of the upper pillars 5 and the walls 6 with anchors 13 .
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the RC seismic isolation structure according to the first and second aspects of the present invention are shown in FIGS.
The seismic isolation structure according to the present invention is a structure that rocks and vibrates in the same manner as the building 1 illustrated in FIG. 1B, and has a “floating boundary surface”. ) To reduce the seismic force, and is suitably implemented as a seismic isolation structure that ensures safety against overturning and dropping impact of the structure.
[0011]
That is, as shown in FIG. 2, the edge of the lower part of the intermediate floor or basement part in the pillar 5 and the wall 6 of the structure and the pillar 5 'or the beam 7 below the lower part is cut between the two. A “floating boundary surface K” is formed.
[0012]
Horizontal shearing force transmission projections 9 and 10 are installed on the lower column 5 ′ or the beam 7 by the anchor 8 and are raised on the surface of the floating boundary surface K.
On the other hand, on the lower part of the pillar 5 and the wall 6 of the structure, a protrusion cover 12 having a downward recess 11 into which the horizontal shearing force transmission protrusions 9 and 10 are respectively fitted is fixed integrally by an anchor 13. Installed.
[0013]
A concave portion 11 of a direction formed on the pillar 5 of the structure and the projection cover 12 below the wall 6 is fitted to the horizontal shearing force transmission projections 9 and 10 provided on the lower column 5 ′ or the beam 7. An energy absorbing device 14 for lifting is installed in the fitting gap between the two.
[0014]
However, as a specific method of seismic isolation, first, when constructing the lower column 5 ′ or the beam 7, the horizontal shearing force transmission protrusions 9 and 10 rising on the upper surface (floating boundary surface K) are preceded. And install. Then, prior to the work of constructing the pillar 5 and the wall 6 of the structure above the rising boundary surface K, the projection cover 12 is placed on the surface of the rising boundary surface K, and each recess 11 is subjected to the corresponding horizontal shear. The force absorbing projections 9 and 10 are fitted and laid together with the energy absorbing device 14. In that case, the protrusion cover 12 is placed directly on the surface of the raised boundary surface K of the lower column 5 ′ or the beam 7 to be in a surface contact state, or a shock absorbing material such as a rubber sheet is spread over a certain thickness. It implements as a buffer structure installed on the lever (the invention according to claim 2).
[0015]
After that, on the outer periphery and the upper part of the protrusion cover 12, the formwork and the reinforcing bars for constructing the pillar 5 and the wall 6 of the structure above the rising boundary surface K are assembled, and the protrusion cover 12 is integrated by placing concrete. Do the construction to be.
[0016]
As the energy device 14 in the illustrated example, a gel-like and highly viscous viscoelastic body that absorbs energy by vertical shear deformation is used. Therefore, energy is absorbed by using the vertical shear deformation when the pillar 5 and the wall 6 of the structure are lifted, or conversely, thereby reducing the seismic force and limiting the amount of lift, preventing the fall, falling It has effects such as shock mitigation .
[0017]
The fitting portion between the concave portion 11 of the projection cover 12 installed at the lower end of the pillar 5 and the wall 6 of the structure and the horizontal shear force transmission projections 9 and 10 provided on the lower column 5 ′ or the beam 7 is an earthquake. Transmits horizontal shear force and vertical compression force. Therefore, the height of the concave portion 11 and the horizontal shearing force transmission projections 9 and 10 and the size of the planar shape are designed to be necessary and sufficient for the above-described effects.
[0018]
In the case of seismic isolation at the time of rebuilding an existing building, the existing foundation or existing frame is lifted up to the boundary surface K so as to substitute for the lower pillar 5 'or the beam 7, and the above-mentioned Thus, the pillar 5 and the wall 6 of the structure that rises above the boundary surface K are constructed. In this way, it is possible to build a base-isolated structure, and to achieve significant rationalization and labor saving of foundation design and construction.
[0019]
[Effects of the present invention]
The seismic isolation structure according to the first and second aspects of the present invention realizes a seismic isolation structure that utilizes the characteristics of reinforced concrete structure to allow the lift generated in the structure during an earthquake to reduce seismic force it can.
[0020]
Moreover, safety can be ensured by limiting the above-mentioned lifting amount to prevent overturning and buffering the drop impact of the structure.
Furthermore, seismic isolation structures can be realized not only in newly built buildings, but also in the reconstruction of existing buildings, while greatly rationalizing the foundation design and construction.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining the principle of a conventional seismic isolation structure according to the present invention, and FIG.
FIG. 2 is a cross-sectional view showing an embodiment of the present invention.
3 is a cross-sectional view taken along line 3-3 in FIG.
[Explanation of symbols]
5 Structure pillar 6 Wall 7 Beam 5 'Lower floor pillar K Lifting boundary surface 9, 10 Protrusion 11 for transmitting horizontal shear force Recess 12 Protrusion cover 14 Energy absorbing device

Claims (2)

In the seismic isolation structure, which is reinforced concrete structure, allows for the lifting that occurs at the time of an earthquake and reduces the seismic force, ensuring the safety of the structure to fall, drop impact,
The upper floor of the pillars and walls of the structure, cut the edge of the lower floor of the pillars and beams, the floating interface is formed,
A projection for horizontal shear force transmission integrated with the pillar and beam on the lower floor is launched on the floating boundary surface of the floor and beam on the lower floor,
A protrusion cover having a downward concave portion into which the horizontal shearing force transmission protrusion fits is installed at the lower floor of the upper floor pillar and wall,
The horizontal shear force transfer protrusion is a recess in the protrusion cover fitted, the mating gap therebetween, the viscoelastic body of high viscous gel is provided as an energy absorbing device when floating,
Seismic isolation structures characterized by each. The lower boundary of the pillar and beam on the lower floor and the protrusion cover installed on the lower floor of the upper floor and the wall are in direct surface contact, or a shock absorbing structure with a shock absorber such as a rubber sheet in between. The seismic isolation structure according to claim 1, wherein the protrusion cover is fixed to the upper floor pillar and the lower end of the wall with an anchor.

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