JP5386321B2 - Peripheral structure of base seismic isolation - Google Patents

Description

  The present invention relates to a peripheral structure of a base-isolated base.

  As earthquake countermeasures, various seismic isolation devices have been proposed that absorb the shaking during an earthquake by receiving the building body with a support material and separating it from the ground surface.

  However, in the conventional seismic isolation device in which the base isolation material is provided between the foundation and the building body, there is a problem that a structural frame for supporting the building body has to be provided, and the cost for the frame increases. .

  Under the circumstances, a base-isolation system has been proposed in which a sliding surface is provided between the foundation supporting the building frame and the ground surface.

Japanese Patent Laid-Open No. 2003-147783

  However, in the seismic isolation structure under the foundation, the entire building including the foundation moves against the ground surface at the time of the earthquake and does not transmit the shaking of the earthquake. It is crushed with the displacement of the entire building including the foundation without being discharged during the base-isolation operation. For this reason, resistance varies depending on the hardness of the backfill soil, so it was difficult to design a base-isolated building and to achieve a sufficient seismic isolation effect.

  In addition, in the structure in which the clearance is provided around the foundation in order to eliminate the ambiguity of the soil resistance, the clearance becomes a useless space during normal times, which hinders effective use of the site.

  In view of the above-described problems, the present invention provides a foundation isolation system in which a sliding surface is provided between the foundation supporting the building body and the ground surface. The objective is to provide a peripheral structure within the seismic isolation operating range.

  The above problem is that in the base isolation system with a sliding surface between the foundation that supports the building body and the ground surface, the operation of the base isolation system is within the range of the base isolation system on the outer periphery of the foundation. It is solved by the peripheral structure of the base isolation system that has the compression section to be compressed and the pumping section that is swept out by the operation of the base isolation system.

  Since there is a compression part that is compressed by the operation of the base isolation system and a sweeping part made of soil, for example, that is swept out to the outside by the operation of the base isolation system, within the base isolation operation range of the foundation outer periphery. When the base is under seismic isolation operation, it is swept away from the ground surface around the base isolation base and the base isolation base without being compressed. Therefore, it is possible to quantitatively grasp the resistance force that the sweeping part gives to the building during the seismic isolation operation, and the seismic isolation design can be performed accurately. In particular, by managing the coefficient of friction between the compression part and the sweeping part, the sweeping part can be swept to the foundation periphery with a small force, and the design of the foundation-isolated building can be performed more accurately. .

  Further, within the base-isolated seismic isolation range of the foundation outer periphery, the compression portion is below, the sweep-out portion is above, and the boundary surface between the compression portion and the sweep-out portion is outside the lower end on the outer periphery side of the foundation. It is good to incline diagonally upward toward the direction.

  The boundary between the lower compression part and the upper sweeping part within the base-isolated operating range is inclined diagonally upward from the lower end on the outer peripheral side of the foundation. During operation, the sweeping section can be efficiently swept along the boundary surface to the ground surface around the building. In addition, since the surface of the foundation of the compression part with respect to the outer peripheral side is inclined obliquely upward toward the outer side from the lower end part of the outer periphery of the foundation, less force is required to compress the compression part, and the compression part is the foundation. The impact on the seismic isolation performance can be reduced.

  Furthermore, by providing a compression part made of a compressible member within the base-isolated operation range, it is possible to compactly fit the surrounding parts within the base-isolation operation range. In addition, since unnecessary space can be reduced during normal times, the site can be used effectively in buildings that employ base isolation.

  Moreover, the said compression part is good to consist of bead method polystyrene foam.

  The beaded polystyrene foam (EPS) can be adjusted in compression strength by selecting the expansion ratio, and has the feature of being stably deformed once it starts to be compressed. The necessary force can be grasped quantitatively, and the seismic isolation design can be performed accurately.

  Further, within the base-isolated seismic isolation operating range of the foundation outer periphery, the compression part is provided at a distance from the outer periphery side of the foundation, and the sweep-out part is provided between the compression part and the outer periphery side of the foundation. It is preferable that the boundary surface between the compression portion and the previous sweep portion is inclined obliquely upward toward the outside from the base side, and the compression portion and the sweep portion are made of beaded polystyrene foam.

  Since there is a compression part that is compressed by the operation of the base isolation system and a pumping part that is compressed and / or swept out by the operation of the base isolation system, within the base isolation operation range of the foundation outer periphery. The part is compressed between the ground surface around the base isolation base and the base isolation base or is swept out to the ground surface around the building, depending on the displacement of the base base isolation. Even when the sway backs up in the opposite direction, there is no resistance. In addition, the compression part and sweeping part are made of beaded polystyrene foam (EPS), so the compressive part and the sweeping part can quantitatively grasp the resistance force applied to the building during seismic isolation operation, and the seismic isolation design is performed accurately. be able to. In particular, by managing the coefficient of friction between the compression part and the sweeping part, the sweeping part can be swept to the foundation periphery with a small force, and the design of the foundation-isolated building can be performed in more detail. .

  Furthermore, since the boundary surface between the compression portion and the previous sweep portion is inclined obliquely upward toward the outside from the foundation side, the sweep portion is moved along the boundary surface to the ground surface around the building during base-isolation operation. Efficient sweeping is possible. In addition, the force required for compression of the compression part can be reduced, the influence of the compression part on the performance of the base isolation system can be reduced, and the building of the base isolation system can be designed more accurately. .

  In addition, a boundary member may be interposed between the compression portion and the sweep-out portion.

  Since the boundary member is interposed between the compression portion and the discharge portion, in particular, the boundary member is the boundary surface between the compression portion and the boundary member and between the boundary member and the discharge portion, or the compression portion and the boundary member or the boundary member. If the member does not adhere to any of the boundary surfaces of the sweeping part, the compression part and the sweeping part will not be united in normal times, and the sweeping part will be moved without resistance when the building superstructure moves during an earthquake. Can be swept out.

  Since the present invention is as described above, in the base isolation system with a sliding surface between the foundation supporting the building body and the ground surface, the base isolation operation can be performed on the outer periphery of the foundation that can fully demonstrate the seismic isolation effect. Peripheral structures within range can be provided.

It is a section front view showing an embodiment of the present invention. It is a graph which shows the triaxial compression test result of bead method polystyrene foam (EPS). Drawing (a) thru / or (c) is a section front view which shows in order the situation where the backfilling soil of a sweeping part is swept away at the time of an earthquake. It is a sectional front view showing other embodiments of the present invention. FIGS. 1A to 1C are cross-sectional front views sequentially showing a situation in which a sweeping portion is swept out during an earthquake.

  Next, embodiments of the present invention will be described with reference to the drawings.

  In the base isolation system shown in FIG. 1, 3 is an upper structure comprising an upper foundation 1 and a building body 2 that support the building body, and 4 and 5 are provided within the base isolation system operating range of the outer periphery of the upper foundation, respectively. The compression part 4 is downward, the discharge part 5 is upward, and the boundary surface between the compression part 4 and the discharge part 5 is the ground surface outside the lower end on the outer peripheral side of the upper foundation 1. It is inclined on the straight line in a cross-sectional view obliquely upward. Reference numeral 6 denotes a boundary surface sheet interposed as a boundary member on the boundary surface between the compression unit 4 and the sweep-out unit 5.

  7 is the ground surface on which the base seismic isolation is installed, 8 is the ground foundation that is installed on the ground surface 7 and supports the upper structure 3, 9 is interposed between the upper foundation 1 and the ground foundation 8, and the upper structure 3 is a ground sliding material for smooth side slipping on the ground foundation 8, and 10 is a ground surface outside the foundation-isolated operating range of the outer periphery of the upper foundation of the foundation-isolated.

  The compression part 4 should just select the member which can perform big compression with little force so that it may not become resistance of movement of base isolation, when a base isolation operation is carried out. Here, for example, a bead method polystyrene foam (EPS) Is used. The compression strength of the beaded polystyrene foam (EPS) can be adjusted by selecting the expansion ratio. Furthermore, as shown in FIG. 2, since it has the feature of being deformed stably once it begins to be compressed, it does not affect the performance of the seismic isolation during the seismic isolation operation, and the force required to compress the compression part Can be quantitatively grasped, and seismic isolation design can be performed quantitatively. In addition, the compression part 4 is each divided | segmented for every predetermined space | interval around the outer periphery of the upper base 1 arrange | positioned.

  The sweep-out part 5 is not compressed between the ground surface around the base isolation and the base isolation base by the movement of the base isolation during the base isolation process. It is swept out to the ground surface of the outer peripheral part. The sweep-out unit 5 is selected to have an indeterminate shape and an appropriate weight because the sweep-out unit 5 does not affect the seismic isolation performance during the seismic isolation operation and is gradually swept out to the periphery of the foundation by the movement of the foundation. For example, soil or sand, here, soil dug up when constructing the foundation is used.

  The boundary sheet 6 is installed for the purpose of preventing the compression unit 4 and the sweeping unit 5 from being integrated with the passage of time, and both the boundary surface of the compression unit and the boundary sheet and the boundary sheet and the sweeping unit, or the compression unit. And a boundary surface sheet or a member that does not closely contact any boundary surface between the boundary surface sheet and the sweep-out portion, for example, a polyethylene sheet or the like is used. The boundary sheet 6 prevents the compression part and the sweeping part from being integrated in a normal state, and the sweeping part can be swept to the foundation peripheral part without resistance when the building superstructure moves during the base-isolation operation.

  In this base-isolated structure, after the ground foundation 8 is installed on the ground surface 7, the upper foundation 1 is installed on the ground foundation 8 via the foundation sliding material 9, and the building body 2 is constructed thereon. To do. Since the superstructure 3 is arranged on the ground foundation 8 so as to be relatively movable in the horizontal direction via the foundation sliding material 9, the superstructure 3 is horizontally placed on the ground foundation 8 when a shaking occurs during an earthquake. By moving in the direction, it absorbs the shaking of the earthquake and prevents the building from being damaged by the earthquake.

  One end of the boundary sheet 6 is attached to the outer peripheral side of the lower end surface of the upper foundation 1. In order to prevent foreign matter such as soil from entering between the upper foundation 1 and the foundation sliding material 9, coking or the like is made at the boundary between the lower end surface of the upper foundation 1 and the landslide boundary sheet 6. Good.

  The end of the boundary sheet 6 opposite to the end attached to the lower end surface of the upper foundation 1 is spread on the ground surface 10 of the outer peripheral portion of the upper foundation 1, and the backfilling soil as a sweeping portion from above is spread. Is backfilled. The boundary surface between the compression portion 4 and the sweep-out portion 5 is inclined on a straight line in a cross-sectional view obliquely upward toward the ground surface 10 outward from the lower end on the outer peripheral side of the upper foundation 1. The backfill soil as the sweep-out unit 5 to be described later is supplely discharged to the ground surface with a small resistance.

  The edge part on the opposite side to the edge part stuck to the lower end surface of the upper foundation 1 of the boundary surface sheet 6 may be folded back so as not to disturb the normal time without an earthquake and embedded in the sweeping part 5. And an edge part may be cut off to the dimension which does not protrude from the ground surface.

  Although not shown in the drawings, in the base-isolated structure, in addition to the sliding mechanism between the ground foundation 8 and the upper structure 3, the damping device that attenuates the vibration caused by the earthquake and the upper structure 3 after the earthquake has ended It is composed of devices such as an origin return device that returns to a position and a wind sway prevention device that prevents the building from being shaken by wind during normal times.

  In the event of an earthquake, the area surrounding the base isolation system functions as follows.

  As shown sequentially in FIG. 3, when an earthquake occurs in the normal state of FIG. (A) and the upper structure 3 swings horizontally on the ground foundation 8, the upper structure 3 is moved horizontally as shown in FIG. Move (to the left). The movement of the upper structure 3 compresses the compression part 4 and sweeps backfill soil as the sweeping part 5 to the side. One end of the boundary surface sheet 6 is affixed to the lower end surface of the upper foundation 1, and the boundary surface sheet 6 affixed to the lower end surface of the upper foundation 1 is also moved to the peripheral side by the movement of the upper foundation 1. Pressed. When the backfill soil is pushed by the upper foundation 1, it slides on the boundary sheet 6 and is swept out on the ground surface. However, since the backfill soil slides on the boundary sheet 6, the backfill soil becomes the upper foundation. The frictional resistance when sweeping out by 1 can be quantitatively grasped.

  As shown in the figure (c), when the superstructure 3 moves in the reverse direction (rightward) due to the shaking of the earthquake, the superstructure 3 moves horizontally on the ground foundation 8 and is swept back. The soil remains on the ground 10 or a part of it collapses on the boundary sheet 6 but does not restore to the original position after being swept out. Therefore, even if the upper structure 3 is moved again in the first direction (left direction), the backfilling soil does not become a resistance.

  Further, when the upper structure 3 moves in the reverse direction (rightward direction), the backfill soil around the upper foundation 1 is swept out in the same manner as described above.

  The backfill soil is swept along the landslide boundary surface to the outer periphery of the foundation, and the friction coefficient between the landslide boundary surface and the backfill soil is managed to reduce the friction resistance when the backfill soil is swept out. It is possible to grasp quantitatively and to design the base seismic isolation structure accurately.

  In addition, the boundary surface between the lower compression part and the upper sweeping part within the lower base isolation operation range is inclined obliquely upward from the lower end on the outer peripheral side of the foundation. During the seismic isolation operation, the sweeping part can be efficiently swept along the boundary surface to the ground surface around the building. In addition, the force required for compression of the compression part can be reduced, the influence of the compression part on the performance of the base isolation system can be reduced, and the building of the base isolation system can be designed more accurately. .

  Furthermore, by providing a compression part made of a compressible member within the base-isolated operation range, it is possible to compactly fit the surrounding parts within the base-isolation operation range. In addition, since unnecessary space can be reduced during normal times, the site can be used effectively in buildings that employ base isolation.

    In particular, by using a boundary surface sheet as a boundary member between the backfill soil and the ground surface, the backfill soil is more effective than the landslide boundary surface formed by the boundary between the backfill soil and the ground surface. Swept to the outer periphery.

  In the second embodiment of the present invention shown in FIG. 4, 3 is an upper structure composed of an upper foundation 1 and a building body 2 that support the building body, and 4 and 5 are base-isolation operations on the outer periphery of the upper foundation 1. The compression part 4 is provided within the range, and the compression part 4 is provided within the base-isolated seismic operation range of the outer peripheral part of the upper foundation 1 with a space from the outer peripheral side of the upper foundation 1, while The part 5 is provided between the compression part 4 and the outer peripheral side of the upper foundation 1, and the boundary surface between the compression part 4 and the discharge part 5 is inclined obliquely upward toward the outside from the foundation side. . The compression section 4 and the sweep-out section 5 are made of separate beaded polystyrene foam (EPS), which can be compressed with little force so as not to resist the movement of the base isolation system during the base isolation process. ing. Moreover, the compression part 4 and the sweep-out part 5 are each divided | segmented for every predetermined space | interval around the outer periphery of the upper base 1 arrange | positioned. Note that soil 11 is spread on the surface portion for makeup.

  The sweep-out unit 5 is configured so that the base surface 10 or / and the compression unit 4 around the base seismic isolation can be used when the base structure 3 of the base seismic isolation moves when the base seismic isolation operation is performed. When it is compressed between seismic foundations and the amount of movement is large, the outer surface of the foundation including the upper part of the compression part 4 from the ground surface 10 or / and between the compression part 4 and the base isolation base part around the base isolation base It is swept out to the part. The sweep-out portion 5 is made of beaded polystyrene foam (EPS), and has a feature of being stably deformed once compressed as shown in FIG. 2, so that the amount of movement of the upper structure 3 is large and includes the upper portion of the compression portion 4. Not only when it is swept out to the outer periphery of the foundation but also when the amount of movement of the superstructure 3 is compressed small, it does not affect the seismic isolation performance during base isolation operation, and it compresses the compression part The necessary force can be grasped quantitatively, and the seismic isolation design can be performed accurately. Moreover, since the sweep-out portion 5 is made of a standard bead method polystyrene foam (EPS), it does not fall apart and does not adversely affect the performance of the base isolation system. Furthermore, when returning to the base seismic isolation, it can be easily restored to its original state.

  In this base-isolated structure, after the ground foundation 8 is installed on the ground surface 7, the upper foundation 1 is installed on the ground foundation 8 via the foundation sliding material 9, and the building body 2 is constructed thereon. To do. Since the superstructure 3 is arranged on the ground foundation 8 so as to be relatively movable in the horizontal direction via the foundation sliding material 9, the superstructure 3 is horizontally placed on the ground foundation 8 when a shaking occurs during an earthquake. By moving in the direction, it absorbs the shaking of the earthquake and prevents the building from being damaged by the earthquake.

  After the upper foundation 1 is installed, the compression portion 4 is placed on the outer periphery within the base-isolation operation range below the base, and the outer base of the upper foundation 1 is spaced from the outer periphery side within the base-isolation operation range on the outer periphery of the upper foundation 1. Installed around the outer periphery of the upper foundation 1. And the surface which the sloping part 5 inclines diagonally upwards toward the outer side from the foundation side between the compression part 4 and the outer peripheral side of the upper foundation 1 between the compression part 4 and the sweeping part 5 Install while matching. In addition, when the compression part 4 and the sweep-out part 5 are each divided | segmented by the predetermined space | interval around the outer periphery of the foundation structure 3 arrange | positioned, the piece-shaped compression part 4 and the sweep-out part 5 are each installed sequentially I will do it. Finally, the soil 11 may be packed into the surface layer for makeup.

  As shown sequentially in FIG. 5, when an earthquake occurs from the normal time in FIG. 5 (a) and the upper structure 3 swings horizontally on the ground foundation 8, the upper structure 3 moves in the horizontal direction (left direction). When the amount of movement of the upper structure 3 is small, the compression unit 4 is compressed and the sweeping unit 5 is also compressed. However, as shown in the figure (b), when the amount of movement of the upper foundation 1 is large, the compression unit 4 is compressed, while the sweeping unit 5 is compressed, and the sweeping unit 5 is moved outward. Since the pushing force is applied from the upper structure 3, it is swept outward along a surface inclined obliquely upward toward the outside from the base side which is the boundary between the compression portion 4 and the sweeping portion 5. Even when the sweeping-out unit 5 is swept out, the resistance is the frictional resistance of the boundary surface between the compression unit 4 and the sweeping-out unit 5 and can be quantitatively grasped.

  As shown in the figure (c), when the superstructure 3 moves in the reverse direction (rightward) due to the shaking of the earthquake, the superstructure 3 moves horizontally on the ground foundation 4, and the sweep-out unit 5 It remains on the ground surface 10 or collapses between the outer peripheral side of the upper foundation 1 and the compression part 4, but even if it collapses, the sweep-out part 5 has a highly compressible polystyrene foam (EPS). Therefore, when moving in the first direction (left direction) again, there is no resistance when the upper foundation 1 moves.

  Further, when the upper structure 3 moves in the reverse direction (right direction), the sweep-out part 5 around the upper base 1 is swept out in the same manner as described above.

  In this embodiment, the sweeping part is swept to the outer peripheral part of the foundation, and the frictional resistance of the sweeping part during sweeping is quantitatively grasped by managing the friction coefficient of the interface between the sweeping part and the compression part. It is possible to accurately design the base-isolated structure.

  Furthermore, the sweeping part is made of a compressible member, and it is made of an integral member that can be swept to the outer peripheral part. It is possible to respond without changing the peripheral part. In addition, when there is a large variation in the superstructure during base-isolation operation, the sweep will be swept out, but the swept portion is made of an integral member, so it will be swept out on the ground surface, so the original position will be restored. It is only necessary to return to, and the recovery work can be easily performed. In addition, the force required for compression of the compression part can be reduced, the influence of the compression part on the performance of the base isolation system can be reduced, and the design of the base isolation system can be performed in more detail. .

  In addition, by providing a compression part consisting of compressible members and a sweeping part that can be swept out to the outer peripheral part within the base seismic isolation operation range, the peripheral part can be stored within the base base isolation operation range. Since the space can be reduced to a compact size and unnecessary space can be reduced in normal times to realize base-isolation, the site can be used effectively in buildings that use base-isolation.

  Although the embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications can be made without departing from the spirit of the invention. For example, in the above-described embodiment, the case where the boundary surface between the compression portion and the sweep-out portion is inclined in a straight line in cross section is shown, but the shape of the boundary surface is limited to the case in which the boundary surface is inclined in a straight line in cross section. The shape of the boundary surface may be a downwardly convex arc shape, an upwardly convex arc shape, or another shape.

  Further, in the above embodiment, the shape of the upper foundation has been shown for the case where the base portion does not protrude laterally from the rising portion or the case where the base portion protrudes laterally, but the shape of the base foundation is not limited. Needless to say.

  In the above embodiment, the boundary sheet as the boundary member is shown. However, the boundary member may not be provided, and the material of the boundary member is not limited to the boundary sheet. Alternatively, sprayed paint may be used, and any coating material can be used as long as the friction coefficient between the compression portion and the discharge portion is managed.

DESCRIPTION OF SYMBOLS 1 ... Upper foundation 2 ... Building body 3 ... Upper structure 4 ... Compression part 5 ... Sweeping part 6 ... Boundary surface sheet 7 ... Ground surface 8 ... Ground foundation 9 ... Slip material under foundation 10 ... Ground surface

Claims (5)

In the seismic isolation under the foundation that makes the sliding surface between the foundation supporting the building body and the ground surface,
Within the base seismic isolation operating range of the outer periphery of the foundation,
A compression part that is compressed by the operation of the base isolation system;
Peripheral structure of the base isolation system with a sweeping section that is swept out to the outside by the operation of the base isolation system. Within the seismic isolation operation range of the outer periphery of the foundation,
The compression part is on the lower side and the sweeping part is on the upper side;
The peripheral part structure of a base isolation system according to claim 1, wherein a boundary surface between the compression part and the discharge part is inclined obliquely upward toward the outside from the lower end part on the outer peripheral side of the foundation.   The peripheral structure of the base isolation system according to claim 1, wherein the compression part is made of a beaded polystyrene foam. Within the seismic isolation operation range of the outer periphery of the foundation,
The compression part is provided at an interval from the outer peripheral side of the foundation,
The sweep-out part is provided between the compression part and the outer peripheral side of the foundation,
The boundary surface between the compression portion and the sweep-out portion is inclined obliquely upward toward the outside from the base side,
The peripheral structure of the base isolation system according to claim 1, wherein the compression part and the sweep-out part are made of beaded polystyrene foam.   The peripheral structure of a base isolation system according to claim 1, wherein a boundary member is interposed between the compression portion and the sweep-out portion.

Images