JPH09105247A - Excessive deformation preventing device for base-isolated building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a fall of a building, while securing the base isolation function. SOLUTION: In a base isolation building, in which a building 1 is supported on a foundation 3 through a base isolation device 4 and landing legs 6, which respectively land on the foundation 3 when a deformation is generated by the vertical movement at an allowable value or more, are intermittently provided in a lower end of the building 1, a horizontal material 11 is stretched between the landing legs 6, 6 in the condition that both ends thereof are fixed to each landing leg 6, 6. An arch-shaped frame 12 is projected in the foundation 3 side so as to ride over the horizontal material 11, and spaces H1, H2 for allowing the deformation between an upper lateral material 12a of the frame 12 and the horizontal material 11 and between a vertical material 12b of the frame 12 and the horizontal material 11 are secured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for preventing excessive deformation of a seismic isolated building, which is particularly designed to improve safety against an earthquake directly below.

[0002]

2. Description of the Related Art Conventionally, as a building that has taken measures against earthquakes,
Separate the entire building from the foundation and float it, insert a laminated rubber as a seismic isolation element between the lower end of the building and the foundation, and provide a damper between the outer wall at the lower end of the building and the foundation, A seismic isolated building is known in which the natural frequency of the vibration system consisting of the building and its support is reduced. In this seismic isolated building, the natural period of the building becomes longer than the predominant period of seismic waves due to the insertion of laminated rubber, so the seismic force acting on the upper building can be reduced and the vibration energy is absorbed by the damper. Therefore, the safety of the building can be secured.

In such a seismic isolated building, as a device for preventing the building from being excessively deformed in the horizontal direction at the time of an earthquake, for example, a pit is provided around the outer wall so that the pit is provided when an excessive horizontal deformation occurs. It is known that the walls of the building prevent deformation of the building.

[0004]

However, the conventional excessive deformation prevention device installed in the seismic isolated building cannot cope with a case where a seismic force acts in the vertical direction such as a direct earthquake. In the worst case, it turned out that the situation of falling the building could not be prevented.

In consideration of the above-mentioned circumstances, the present invention is effective in the case where a large vertical seismic force such as a direct earthquake is applied.
An object of the present invention is to provide a device for preventing excessive deformation of a seismic isolated building that can reliably prevent excessive deformation (for example, falling) of the building.

[0006]

According to the apparatus for preventing excessive deformation of a first aspect of the present invention, a building is supported on a foundation via a seismic isolation device, and the lower end of the building is deformed by vertical movement exceeding a permissible value. In a seismic isolated building where landing legs that land on the foundation at intervals are projected, between the landing legs, both ends are fixed to each landing leg and a horizontal member is erected, and on the foundation side , A gate-shaped frame is provided so as to straddle the horizontal member, and deformation is allowed between the upper horizontal member of the frame and the horizontal member and between the vertical member of the frame and the horizontal member. It is characterized by securing the interval of.

The excessive deformation prevention device according to the second aspect of the invention supports the building on the foundation via a seismic isolation device, and when the lower end of the building is deformed by vertical movement more than an allowable value, it is attached to the foundation. In a seismic isolated building with landing legs projecting at intervals, two parallel horizontal members are erected between the landing legs by fixing both ends to each landing leg, and at the foundation side. ,
A T-shaped frame is provided by projecting a vertical member between the two horizontal members and intersecting an upper horizontal member above the two horizontal members, and connecting the upper horizontal member of the frame and the horizontal member. And a vertical member of the frame and the horizontal member are provided with a space for allowing deformation.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1A shows the lower structure of the seismic isolated building 1 of the embodiment, and FIG. 1B shows the details of the main part thereof. This building 1 is a middle-high-rise building such as a reinforced concrete structure, a steel frame reinforced concrete structure, or a steel frame structure. The lower end of the pillar 2 of the building 1 is supported by the base 3 via a horizontal seismic isolation device (laminated rubber) 4.

On the foundation beam 5 at the lower end of the building 1, a plurality of landing legs 6 that land on the upper surface of the foundation 3 when they are deformed by a vertical movement exceeding a permissible value are projected downward at intervals. Has been done. The excessive deformation prevention device 10 is installed between the adjacent landing legs 6, 6. This excessive deformation prevention device 10
Is composed of a horizontal member 11 installed between the landing legs 6 and 6, and a plurality of gate-shaped frames 12 projectingly provided on the foundation 3 so as to straddle the horizontal member 11. Both the horizontal member 11 and the frame 12 are made of shaped steel. Both ends of the horizontal member 11 are fixed to the landing legs 6 and 6, and an intermediate portion of the horizontal member 11 is supported by the support beam 5 by the support member 14 due to its length. Further, in the gate-shaped frame 12, the lower ends of the vertical members 12b, 12b on both sides are fixed to the foundation 3.

The gate-shaped frame 12 is constructed as a frame body which is slightly larger than the horizontal member 11, and is arranged at intervals along the extending direction of the horizontal member 11. Then, between the upper horizontal member 12a of the frame 12 and the horizontal member 11, and between the vertical members 12b and 12b of the frame 12 and the horizontal member 11, respectively, the vertical direction (the arrow Z direction in the figure) and the horizontal direction ( Intervals H1 and H2 are secured to allow deformation in the direction of arrow X in the drawing.

In the seismic isolated building thus constructed, the vertical members 12b, 12b of the gate-shaped frame 12 provided on the foundation 3 side.
Since an interval H2 for allowing deformation is secured between the horizontal member 11 and the horizontal member 11 provided on the side of the building 1, the building 1 is within that range.
The foundation 3 can move horizontally relative to each other, and the seismic isolation function in the horizontal direction is secured. Further, when the deformation due to the relative movement becomes excessive, the vertical members 12b, 12b of the frame 12 and the horizontal member 11 come into contact with each other, thereby preventing the excessive deformation in the horizontal direction. Further, since the space H1 for allowing deformation is secured between the upper horizontal member 12a of the frame 12 on the side of the foundation 3 and the horizontal member 11 on the side of the building 1, the building 1 and the foundation 3 are in that range.
Can move up and down relative to each other. Further, when the deformation due to the relative movement becomes excessive and the upward pulling force acts on the building 1, the upper transverse member 12a of the frame 12 and the horizontal member 11 come into contact with each other, thereby resisting the pulling force.

Therefore, even if the building 1 is subjected to a vertical falling force due to a strong direct earthquake, the building 1 can be prevented from falling. In addition, when the building 1 is displaced downward due to a downward force acting on the building 1 or the horizontal deformation is excessive, the landing legs 6 land on the upper surface of the foundation 3, Prevents further deformation. Therefore, both the horizontal excessive deformation and the vertical excessive deformation can be prevented, and the safety of the building 1 can be improved.
Further, since the excessive deformation preventing device 10 is configured by the combination of the horizontal member 11 and the gate-shaped frame 12, it can be constructed at low cost.

FIG. 2 shows an example of installation of the excessive deformation prevention device 10. As shown in Figure (a), the length of one side is large,
In the case of a building with a rectangular cross section where the length of the other side is small, it is easy to deform in the horizontal direction in the arrow X direction (direction parallel to the short side).
So that the deformation prevention function of the excessive deformation prevention device 10 works,
It is desirable to install the excessive deformation prevention device 10 with the horizontal member 11 oriented in the Y direction (direction parallel to the long side). Further, as shown in FIG. (B), in the case of a building having a cross-section having a shape in which the easiness of deformation is not biased (that is, a square, or a polygon based on the square), the direction of the horizontal members 11 is orthogonal. It is desirable to install the excessive deformation prevention device 10 in two directions (X direction, Y direction).

Next, another embodiment of the present invention will be described with reference to FIG. In the excessive deformation prevention device 20 of this embodiment, both ends of the landing legs 6 and 6 are provided between the landing legs 6 and 6, respectively.
Two parallel horizontal members 11, 11 are fixedly attached to the bridge. Then, on the foundation 3 side, the upper cross member 22a and the vertical member 22
A T-shaped frame 22 made of b is projected, the vertical member 22b is positioned between the two horizontal members 11, 11, and the upper horizontal member 22a is crossed above the two horizontal members 11, 11. There is. Further, between the upper horizontal member 22a of the frame 22 and the horizontal members 11 and 11, and between the vertical member 22b of the frame 22 and the horizontal members 11 and 11, respectively, the vertical direction (arrow Z direction in the figure) and the horizontal direction ( Intervals H1 and H2 are secured to allow deformation in the direction of arrow X in the figure.

In the seismic isolated building provided with the excessive deformation preventing device 20, between the vertical member 22b of the T-shaped frame 22 provided on the foundation 3 side and the horizontal members 11, 11 provided on the building (not shown) side. In addition, since the space H2 for allowing deformation is secured, the building and the foundation 3 can be horizontally moved relative to each other within that range, and a horizontal seismic isolation function is secured. Further, when the deformation due to the relative movement becomes excessive, the vertical member 22b of the frame 22 hits the horizontal members 11, 11 to prevent the excessive horizontal deformation. Also, the upper cross member 2 of the frame 22 on the side of the foundation 3
Since the space H1 for allowing deformation is secured between 2a and the horizontal members 11, 11 on the building side, the building and the foundation 3 can move relative to each other in the vertical direction within that range. When the deformation due to the relative movement becomes excessive and the upward pulling force acts on the building 1, the upper transverse member 12a of the frame 12 and the horizontal member 11 come into contact with each other, thereby resisting the pulling force. Therefore, it is possible to prevent the building from falling over even when the building has a vertical falling force due to a strong direct earthquake. Other effects are the same as those in the above-mentioned embodiment.

[0016]

As described above, according to the inventions of claims 1 and 2, since the gate-shaped, T-shaped frame on the foundation side and the horizontal member on the building side are combined, excessive horizontal deformation and vertical movement It is possible to prevent both excessive deformation of the direction, and even if the vertical seismic force is predominantly exerted, such as a direct earthquake, it is possible to prevent the building from falling over and ensure the safety of the building. can do. Further, since it is composed of a combination of a horizontal member and a gate-shaped or T-shaped frame, it can be constructed at low cost.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention, in which (a) is a side view and (b) is a perspective view of an essential part thereof.

FIG. 2 is a diagram showing an arrangement example of an excessive deformation preventing device of an embodiment for a building.

FIG. 3 is a perspective view showing a main part configuration of another embodiment of the present invention.

[Explanation of symbols]

 1 building 3 foundation 4 seismic isolation device 6 landing leg 10, 20 excessive deformation prevention device 11 horizontal member 12 gate-shaped frame 12a upper horizontal member 12b vertical member 22 T-shaped frame 22a upper horizontal member 22b vertical member

Claims (2)

[Claims] 1. A building is supported on a foundation via a seismic isolation device, and landing legs that land on the foundation are projected at intervals when the lower end of the building is deformed due to vertical movement more than an allowable value. In the seismic isolated building installed, a horizontal member is installed between the landing legs by fixing both ends to each landing leg, and a gate-shaped frame is projected on the foundation side so as to straddle the horizontal member. However, the seismic isolation building is oversized, in which a space for allowing deformation is secured between the upper horizontal member of the frame and the horizontal member and between the vertical member of the frame and the horizontal member. Deformation prevention device. 2. A building is supported on a foundation via a seismic isolation device, and landing legs for landing on the foundation are projected at intervals when the lower end of the building is deformed by vertical movement more than an allowable value. In the seismic isolated building installed, two parallel horizontal members are installed between the landing legs by fixing both ends to each landing leg, and on the foundation side, between the two horizontal members. A T-shaped frame is provided by projecting a vertical member and crossing an upper horizontal member above two horizontal members, and between the upper horizontal member of the frame and the horizontal member, and a vertical member of the frame. A device for preventing excessive deformation of a seismic isolated building, characterized in that a space for allowing deformation is secured between the horizontal member and the horizontal member.