JP2006016911A - Seismic isolation structure - Google Patents

Abstract

PROBLEM TO BE SOLVED To realize a pendulum type large-scale seismic isolation structure.
SOLUTION: A plurality of tower-like structures 1 are erected on the ground, and suspension support structures 4 are provided on the tops of the tower-like structures 1 via seismic isolation mechanisms 3, respectively. The structure 2 is suspended and supported and arranged around the tower structure. The plate-like structure of each layer is provided with an opening through which the tower-like structure penetrates to ensure seismic isolation clearance, and the lowermost plate-like structure is placed on the ground surface. A plate-like structure of each layer is provided as an artificial ground. A stiffening mechanism that restrains torsional deformation in the out-of-plane direction of the plate-like structure is provided. The suspension member 11 and the brace 12 are gathered and arranged on the outer periphery of the plate-like structure. As the seismic isolation mechanism, a structure in which a plurality of seismic isolation devices are arranged above and below the swing support structure in an inclined state so as to face the virtual rotation center, respectively.
[Selection] Figure 3

Description

  The present invention relates to a seismic isolation structure that can significantly suppress vibration during an earthquake and avoid earthquake damage by making the natural period longer or very long.

As this type of seismic isolation structure, Patent Document 1 proposes a pendulum type earthquake-resistant building. This is based on the top of a high-rigidity core shaft provided in the center of the building as a fulcrum. It responds as a possible pendulum. According to such a structure, it is said that the natural period of the building body can be sufficiently longer than the earthquake motion period, thereby realizing a building that hardly vibrates during an earthquake.
JP 2001-90374 A

  Although the above-mentioned seismic isolation structure is considered to be extremely effective, it has not yet been realized at the present stage. In particular, this type of seismic isolation structure is expected to be applied to large-scale structures. However, as shown in Patent Document 1, the building body is simply swung in all directions from the top of the core shaft. In the form of suspension support where possible, there is a limit to the increase in scale naturally, so the development of effective improvement measures in this respect is indispensable in order to put this type of seismic isolation structure into practical use and dissemination. It was.

  In view of the above circumstances, the seismic isolation structure of the present invention has a plurality of tower-like structures standing on the ground, and a suspension support structure is provided on the top of each tower-like structure via a seismic isolation mechanism. The plate-like structures of a plurality of layers are suspended and supported from the suspension support structures and arranged around the tower-like structures, and the plate-like structures of the respective layers are provided with openings through which the tower-like structures penetrate. By securing seismic isolation clearance between the inner edge of the opening and the tower-like structure, and placing the lowermost plate-like structure floating above the ground surface, multiple layers of the plate-like structure can It is characterized in that it is suspended and supported from the top of the tower-like structure through a seismic isolation mechanism and a suspension support structure.

  In the seismic isolation structure of the present invention, the plate-like structure of each layer can be provided as an artificial ground for constructing various buildings and facilities, in other words, an aerial ground. In addition, the seismic isolation clearance between the inner edge of the opening formed in the plate-like structure of each layer and the tower-like structure has a plate-like structure while allowing horizontal displacement of the plate-like structure relative to the tower-like structure. It is preferable to provide a stiffening mechanism that restrains torsional deformation in the out-of-plane direction of the body. In addition, a suspension material for supporting and supporting the plate-like structures and a brace for connecting the plate-like structures together to restrain interlayer displacement are provided on the outer periphery of the plate-like structures of each layer. It is preferable to provide it. Furthermore, as the seismic isolation mechanism, a swing support structure and an assembly of a plurality of seismic isolation devices arranged in an inclined state so as to face the virtual center of rotation above and below the swing support structure, respectively. A thing can be employ | adopted suitably.

  The seismic isolation structure of the present invention comprises a plurality of tower-like structures dispersedly installed, and the entire plate-like structure of a plurality of layers is suspended and supported by the plurality of tower-like structures, thereby providing the plate-like structures. The number of installed bases and their positions should be set according to the scale of the plate-like structure as well as the natural period of the whole body being sufficiently long to provide an excellent seismic isolation effect. Thus, even a large-scale plate-like structure can be stably suspended and supported, so that the entire seismic isolation structure can be enlarged without any problem.

  In addition, by providing the lowermost plate-like structure floating on the ground surface, an open space can be secured on the ground surface, so that the plate-like structure can be installed so as to straddle the existing infrastructure, Alternatively, it is possible to leave the natural environment as it is on the ground surface below the plate-like structure. Therefore, in the present invention, by providing the tower-like structure and the plate-like structure as a large-scale megastructure, the plate-like structure itself of each layer can be made to function as a large-scale artificial ground such as a block. In that case, it is possible to install various independent buildings and facilities as infills as an aerial ground. Since the effect can be obtained, the building or facility installed there does not need an earthquake-resistant element.

  The suspension material for supporting the plate-like structure of each layer is equivalent to a pillar in a general structure, but it may have a small cross section with tensile strength, and the plate-like structure of each layer. Interlayer displacement of each layer can be effectively prevented by connecting the two together with braces, and the suspension material and braces are both concentrated on the outer periphery of the plate-like structure so as to be inside the plate-like structure. Can be provided with a substantially column-free large space simply by disposing a tower-like structure, and is suitable as a flexible skeleton structure for installing a building or facility as an infill.

  In addition, since the tower-like structures are arranged inside the openings formed in the plate-like structures and the seismic isolation clearance is secured between them, the plate-like structures can be allowed to swing without any trouble. By providing a stiffening mechanism that constrains the torsional deformation of the plate-like structure in the seismic isolation clearance, it is possible to compensate for the reduction in torsional rigidity due to the large scale of the plate-like structure by the stiffening mechanism. The torsional deformation of the plate-like structure can be effectively prevented.

  Furthermore, as a seismic isolation mechanism, a structure in which a plurality of seismic isolation devices are installed above and below the swinging support structure, and these seismic isolation devices are arranged in an inclined state so as to face the virtual rotation center, respectively. By adopting it, not only can a sufficiently long period be realized, but also a seismic isolation effect can be effectively exhibited for various vibration modes.

  One embodiment of the seismic isolation structure of the present invention is shown in FIGS. The seismic isolation structure of the present embodiment is a structure in which a total of five layers of plate-like structures 2 are suspended and supported via the seismic isolation mechanism 3 and the suspension support structure 4 from the tops of the two tower-like structures 1. In the event of an earthquake, the entire plate-like structure 2 responds as a pendulum, so that its natural period has become a very long period, so that an excellent seismic isolation effect can be obtained. .

  The tower-like structure 1 is a reinforced concrete structure with high axial rigidity and high bending rigidity that is erected from the ground in a self-supporting state. It can support all horizontal loads during an earthquake. As shown in FIGS. 4 and 7A, the tower-like structure 1 in the present embodiment has a substantially square horizontal cross section, and the inside thereof is used as a common space such as an elevator or a staircase (that is, in a general building). It is used as a core part), but is constructed as a solid cylindrical wall that is substantially free of openings except for the opening that leads to the interior.

As shown in FIG. 5, a suspension support structure 4 is provided on the top of the tower-like structure 1 via a seismic isolation mechanism 3. The suspension support structure 4 is a high-rigidity structure in which four column members 5 made of steel frames are connected by a beam material 6 and a brace material 7 and assembled in a frame shape, and a seismic isolation mechanism is provided at the top of the tower-like structure 1. 3 is installed so as to be swingable and horizontally displaceable. As shown in FIG. 5, the seismic isolation mechanism 4 includes four base isolation devices 9 such as laminated rubber at the upper and lower corners of the swing support structure 8 having a rectangular frame shape. Or the center of the cylindrical surface) fixed in an inclined state so as to face O ₁ and O ₂ , and the lower four seismic isolation devices 9 are fixed to the top of the tower-like structure 1, and the upper four The four pillar members 5 of the suspension support structure 4 are fixed on the seismic isolation device 9.

  And the plate-like structure 2 of all the five layers is suspended and supported from the suspension support structure 4, and is installed around the tower-like structure 1. That is, as shown in FIG. 3, the uppermost plate-like structure 2 is suspended and supported from the suspension support structure 4 via the main suspension member 10, and the other four layers of the uppermost plate-like structure 2 are supported. The plate-like structure 2 is suspended and supported by a large number of suspension members 11 at predetermined intervals, and the lowermost plate-like structure 2 is arranged at a position floating above the ground surface. The above-described suspension members 11 that support and support the plate-like structures 2 of the respective layers are provided collectively on the outer periphery of each plate-like structure 2, and the plate-like structures 2 of the respective layers are similarly connected to the outer periphery. The braces 12 are provided, and the plate-like structures 2 of all the five layers are integrated by the braces 12 in a state in which the interlayer displacement is constrained to ensure horizontal rigidity as a whole. By being suspended and supported, it behaves as a unit during an earthquake. Each plate-like structure 2 can be formed of, for example, a steel beam and a concrete slab. As the main suspension material 10, the suspension material 11, and the brace 12, a steel material or a cable material excellent in tensile strength may be employed. .

  Due to the structure in which the entire plate-like structure 2 is suspended and supported via the seismic isolation mechanism 3 as described above, the seismic isolation structure of this embodiment can effectively exhibit seismic isolation effects for various vibration modes. Is. That is, as the vibration mode of the whole plate-like structure 2 at the time of an earthquake, as shown in FIG. 6A, a swing mode (swing) in which the whole plate-like structure 2 swings as a pendulum, (b ), A horizontal vibration mode (sway) in which the entire plate-like structure 2 is displaced in the horizontal direction with respect to the tower-like structure 1, and further, the top of the tower-like structure 1 is bent by the bending deformation. However, the seismic isolation mechanism 3 according to the present embodiment can effectively exhibit the seismic isolation effect for all such vibration modes, and the vibration of each mode can be sufficiently obtained. It can be suppressed and quickly attenuated. Since the suspension support points for the plate-like structure 2 are two points by the two tower-like structures 1, the swing mode as shown in FIG. 6 (a) hardly occurs in the long side direction. , (B) and (c), the vibration mode is excellent. In any case, the seismic isolation device 9 is provided in two stages on the upper and lower sides via the swing support structure 8. The natural period of the structure 2 as a whole can be extended to an extremely long period of about 8 to 10 seconds (the long period of the conventional seismic isolation structure is limited to about 3 seconds). The seismic isolation structure that is released and hardly shakes even in the event of a major earthquake, and is thus virtually free from earthquake damage, is realized.

  Further, as shown in FIG. 7, each plate-like structure 2 is formed with an opening 13 through which the tower-like structure 1 can penetrate, and a seismic isolation clearance 14 is formed inside these openings 13. The tower-like structure 1 is arranged in such a manner that a passage 15 to the inside of the tower-like structure 1 is provided via an expansion joint, and the seismic isolation clearance 14 has a plate-like shape of each layer. A stiffening mechanism 20 is provided for restraining torsional deformation while allowing horizontal displacement of the structure 2.

  The stiffening mechanism 20 is capable of in-plane deformation in a pantograph manner, but has out-of-plane rigidity that does not cause deformation in the out-of-plane direction, and has a tower shape as shown in FIG. Between the ends of a pair of fixing members 21 fixed to the structure 1 or the plate-like structure 2, two to four connecting members 22 and an intermediate member 23 are rotatably connected by a pipe 24, respectively. The whole can be deformed in a horizontal plane while always maintaining two parallelograms. Therefore, by installing such a stiffening mechanism 20 in the seismic isolation clearance 14, the horizontal displacement of the plate-like structure 2 with respect to the tower-like structure 1 is allowed without hindrance, and the relative displacement in the vertical direction is restrained. As a result, the torsional deformation of the plate-like structure 2 during an earthquake or storm is effectively restrained. In addition, as such a stiffening mechanism 20, what is shown by Unexamined-Japanese-Patent No. 2004-143694, for example can be employ | adopted suitably.

  According to the seismic isolation structure of this embodiment, as shown in FIG. 3, the total vertical load of the entire plate-like structure 2 is applied to the suspension support structure 4 as the tensile force of the suspension member 11, the brace 12, and the main suspension member 12. Is transmitted to the tower-like structure 1 through the seismic isolation mechanism 3, and is transmitted from the tower-like structure 1 to the ground as a compressive force, whereby the entire plate-like structure 2 is stably suspended and supported. Is. The seismic isolation mechanism 4 can sufficiently lengthen the natural period of the entire plate-like structure 2 to obtain an excellent seismic isolation effect, and the two tower structures 1 can be installed in a distributed manner. By adopting a structure in which the entire plate-like structure 2 is suspended and supported from the tower-like structure 1, the plate-like structure 2 can be sufficiently enlarged, and therefore the tower-like structure 1 and the plate-like structure 1 By providing the structure 2 as a large-scale megastructure, for example, as shown in FIG. 2, the plate-like structure 2 of each layer can be made to function as a large-scale artificial ground serving as a block. In that case, the plate-like structure 2 of each layer becomes a new earth without an earthquake, that is, an aerial earth, and it is used as a skeleton to freely install or update various independent buildings, structures, parks, etc. as infills. In addition, since the aerial ground does not cause an earthquake, it is not necessary to consider earthquake resistance for the buildings and facilities installed there, and a simple structure is sufficient.

  Further, since the lowermost plate-like structure 2 is provided in a floating state on the ground surface, an open space can be naturally secured on the ground surface, so that the plate-like structure body is straddled over the existing infrastructure. 2 or create a new urban function and urban landscape in harmony with nature by securing a rich natural environment on the ground surface below the plate-like structure 2 It is also suitable as a technique.

  Further, as the suspension member 11 for supporting the plate-like structure 2 of each layer and the brace 12 for integrating the plate-like structure 2 of each layer, a pulling material having a small cross section is sufficient, and these suspension members are used. 11 and braces 12 are both concentrated on the outer periphery of the plate-like structure 2, so that the tower-like structure 1 is substantially arranged at two locations inside the plate-like structure 2. It is suitable as a flexible skeleton structure for installing and renewing buildings and facilities as infills. Needless to say, this seismic isolation structure is mainly composed of steel and concrete having excellent strength and durability, so that the durability of the seismic isolation structure can be sufficiently secured and the life can be sufficiently long.

  Although one embodiment of the present invention has been described above, the above embodiment is merely a preferred example, and the present invention is not limited to the above embodiment, and various applications and modifications such as those listed below are possible. Is possible.

  In the above-described embodiment, the five-layer plate-like structure 2 is suspended and supported by the two tower-like structures 1. However, depending on the overall scale, the number of installation bases of the tower-like structure 1 may be large. The number of layers of the plate-like structure 2 may be increased or decreased as appropriate. The planar shape and area of the plate-like structure 2 can be freely set for each layer. For example, it is conceivable to reduce the plane area of the upper layer. For example, as shown in FIGS. 8 (a) and 8 (b), the seismic isolation structure of the above embodiment is installed as a unit in the form of being connected to the front and rear, left and right, or both of them. It is also possible to configure a large-scale seismic isolation structure (in FIG. 8, the number of layers of the plate-like structure 2 is four).

  When the swing of the plate-like structure 2 is assumed due to the wind load, the swing of the plate-like structure 2 is restrained at the normal time, and is released quickly and allowed to swing in the event of an earthquake. A good fuse mechanism should be provided at key points. It is also conceivable to provide a damper for damping the vibration of the plate-like structure 2 more quickly. For example, as shown in FIG. 3, the opening 13 of the lowermost plate-like structure 2 is provided. It is preferable to provide a damper 25 of a type that operates both in the horizontal direction and in the vertical direction between the tower structure 1 and the tower-like structure 1.

  In the above embodiment, it is assumed that the plate-like structure 2 of each layer is provided as an artificial ground. However, the present invention is not limited thereto, and a large-scale seismic isolation building is provided by using the plate-like structure 2 as a floor of each floor and providing an outer wall on the outer periphery. Of course, it is also possible to use. Needless to say, various design changes can be made to the specific configurations of the seismic isolation mechanism 3 and the suspension support structure 4 according to the overall scale and form.

It is an external view which shows the whole schematic structure of the seismic isolation structure which is embodiment of this invention. FIG. FIG. FIG. It is a figure which shows the outline | summary of a seismic isolation mechanism. It is explanatory drawing which shows the operation | movement at the time of the earthquake of a seismic isolation mechanism. It is a figure which shows the outline | summary of a stiffening mechanism similarly. It is a figure which shows another example same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tower-shaped structure 2 Plate-shaped structure 3 Seismic isolation mechanism 4 Suspension support structure 8 Oscillation support structure 9 Seismic isolation device 10 Main suspension material 11 Suspension material 12 Brace 13 Opening 14 Seismic isolation clearance 20 Stiffening mechanism 25 Damper

Claims (5)

  A plurality of tower-like structures are erected on the ground, and suspension support structures are provided on the tops of the tower-like structures via seismic isolation mechanisms, respectively, and a plurality of layers of plate-like structures are provided from the suspension support structures. The plate-like structure of each layer is provided with an opening through which the tower-like structure penetrates, and a seismic isolation clearance is provided between the inner edge of the opening and the tower-like structure. In addition, the lowermost plate-like structure is placed on the ground surface so that the whole of the multi-layer plate-like structure can be supported from the top of multiple tower-like structures. A seismic isolation structure characterized by being supported by swinging through a structure.   The seismic isolation structure according to claim 1, wherein the plate-like structure is provided as an artificial ground for constructing various buildings and facilities.   The base-isolated structure according to claim 1 or 2, wherein the base-isolated clearance between the inner edge of the opening formed in the plate-like structure of each layer and the tower-like structure has a plate for the tower-like structure. A seismic isolation structure provided with a stiffening mechanism for restraining torsional deformation of a plate-like structure in an out-of-plane direction while allowing horizontal displacement of the plate-like structure.   It is a seismic isolation structure of Claim 1, 2, or 3, Comprising: The suspension material for suspending and supporting these plate-like structures on the outer peripheral part of the plate-like structure of each layer, and these plate-like structures mutually A base-isolated structure characterized by providing braces that are connected together to constrain inter-layer displacement.   5. The seismic isolation structure according to claim 1, 2, 3 or 4, wherein the seismic isolation mechanism is tilted so as to face the virtual rotation center at the top and bottom of the swing support structure and the swing support structure. A seismic isolation structure comprising a plurality of seismic isolation devices arranged in a state.

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