JP2020111968A - Base-isolation structure - Google Patents

Abstract

To shorten the construction period of a structure having a base-isolation structure.SOLUTION: A base-isolation structure 1 having a base-isolation part 12 provided above a foundation part 11 of a structure 10, the foundation part 11 including a plurality of first piles 111 and second piles 112 having pile heads with different heights, and the second pile 112 in the foundation part 11 being a foundation pile having a pile head 112a at a position higher than a ground level GL, and at least a part of the base-isolation part 12 being configured to be installed on the pile head 112a of the second pile 112.SELECTED DRAWING: Figure 1

Description

The present invention relates to a seismic isolation structure for a structure.

BACKGROUND ART Conventionally, as a seismic isolation structure for a structure, for example, a seismic isolation structure in which a seismic isolation device is provided in a foundation portion of a structure is known as described in JP-A-2017-222992. With this seismic isolation structure, a seismic isolation device is installed above the pillars that are built on the ground floor, and seismic isolation is achieved without constructing a seismic isolation pit in the basement to reduce the number of construction steps.

JP, 2017-222992, A

By the way, there are cases where it is desired to construct a structure having such a seismic isolation structure at an early stage. However, in the above-mentioned seismic isolation structure, it is necessary to construct columns to install seismic isolation devices on the ground floor. Therefore, it is difficult to shorten the construction period of the seismic isolated structure.

Therefore, an object of the present invention is to provide a seismic isolation structure capable of shortening the construction period of the structure.

That is, the seismic isolation structure according to the present invention is a seismic isolation structure in which a seismic isolation portion is provided on an upper portion of a foundation portion of a structure, and the foundation portion includes a plurality of foundation piles having different pile head heights. The foundation pile includes a foundation pile whose head is higher than the ground level, and the seismic isolation unit is supported by a plurality of foundation piles. According to this seismic isolation structure, the plurality of foundation piles include a foundation pile whose pile head is located at a position higher than the ground level, and the seismic isolation section is supported by the foundation pile. That is, the foundation pile is provided so as to project upward from the ground level, and the seismic isolation unit is supported by the foundation pile. Therefore, it is possible to install the seismic isolation part by omitting the provision of the pillar on the upper part of the foundation pile. Therefore, the construction period of a structure having a seismic isolation structure can be shortened.

Further, in the seismic isolation structure according to the present invention, the seismic isolation portion may be provided at the pile head positions of the plurality of foundation piles. In this case, the plurality of foundation piles include a foundation pile whose pile head is located at a position higher than the ground level, and a seismic isolation section is also provided at the pile head position of the foundation pile. That is, the foundation pile is provided so as to project upward from the ground level, and the seismic isolation unit is provided at the pile head position of the foundation pile. Therefore, it is possible to install the seismic isolation part by omitting the provision of the pillar on the upper part of the foundation pile. Therefore, the construction period of a structure having a seismic isolation structure can be shortened.

Further, in the seismic isolation structure according to the present invention, the plurality of foundation piles have a plurality of foundation piles whose pile heads are located above the ground level, and the pile heads are horizontally located between the foundation piles located above the ground level. A reinforcing beam extending in the direction may be installed. In this case, the reinforcing beam extending in the horizontal direction is installed between the foundation piles in which the pile heads are located higher than the ground level, so that the yield strength of the foundation piles can be improved.

Further, in the seismic isolation structure according to the present invention, the structure may be a structure without a basement floor. In this case, when there is a lower floor that is not used on the ground floor of the structure, it is possible to omit the construction of columns for installing the seismic isolation unit on such a lower floor. Therefore, the construction period of the structure can be shortened.

According to the present invention, the construction period of a structure having a seismic isolation structure can be shortened.

It is a schematic explanatory drawing of the seismic isolation structure which concerns on embodiment of this invention. It is explanatory drawing of the reinforcement beam in the seismic isolation structure of FIG. It is a figure which shows arrangement|positioning of the pile of the structure using the seismic isolation structure of FIG.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description.

FIG. 1 is a schematic explanatory diagram of a seismic isolation structure 1 according to an embodiment of the present invention.

As shown in FIG. 1, the seismic isolation structure 1 according to the present embodiment is configured by providing a seismic isolation portion 12 on an upper portion of a foundation portion 11 of a structure 10. The structure 10 is, for example, a reinforced concrete building, and includes a foundation part 11, a seismic isolation part 12, and an upper structure 15. The upper structure 15 is a part that functions as a building, and has, for example, a beam 13 extending in the horizontal direction and a column 14 extending in the vertical direction. In FIG. 1, for convenience of description, only the frames of the beams 13 and the pillars 14 are illustrated as the upper structure 15. The structure 10 is a building in which the lowest floor is the ground floor and there is no basement floor. The base portion 11 of the structure 10 is a portion that is provided below the structure 10 and that transmits the load of the upper structure 15 to the ground. As the foundation portion 11, for example, a pile foundation is used. The foundation 11 is composed of a plurality of foundation piles and has a first pile 111 and a second pile 112.

The first pile 111 and the second pile 112 are foundation piles having different pile head heights, and for example, ready-made piles are used. Note that cast-in-place piles may be used as the first pile 111 and the second pile 112. Plural first piles 111 and second piles 112 are provided, and two piles are shown in FIG. 1. The first pile 111 and the second pile 112 are provided according to the structure of the structure 10, and may be provided individually or in some cases, two or more may be provided. Further, the foundation part 11 may be provided with three or more types of piles having different pile head heights as long as the foundation portions 11 are provided with different pile head heights.

The pile head 112a of the second pile 112 is located higher than the pile head 111a of the first pile 111. For example, the pile head 111a of the first pile 111 is located below the ground level GL, and the pile head 112a of the second pile 112 is located above the ground level GL. The ground level GL is the ground level at the construction point of the structure 10 and means the height of the ground. A pile head joint 113 is provided on the first pile 111 and the second pile 112. The pile head joint portion 113 is attached to the pile head 111a of the first pile 111 and the pile head 112a of the second pile 112. As the pile head joint portion 113, for example, a pile cap is used. The pile head joint portion 113 has a function of connecting the first pile 111 and the second pile 112 to the seismic isolation portion 12 or the upper structure 15. The pile head joint portion 113 has, for example, a tubular shape and an upper surface closed, and is made of steel. Note that, here, the position of the pile head 112a of the second pile 112 is the position of the upper end surface of the pile head joint portion 113 attached to the second pile 112, but it may be another position. For example, when the pile head joint portion 113 is not attached to the second pile 112, the position of the upper end surface of the second pile 112 may be the position of the pile head.

The pile head 112a of the second pile 112 is located at a position higher than the basic floor level FL of the lowest floor on the ground floor. That is, the second pile 112 is provided so as to project to a position higher than the floor level FL of the lowest floor of the structure 10. In the structure 10 of FIG. 1, the ground level GL and the basic floor level FL of the lowest floor on the ground floor have the same height.

Since the second pile 112 is provided so as to project to a position higher than the ground level GL or the floor level FL of the lowest floor, it is possible to construct all or part of the columns of the lowest floor in the floor area where the second pile 112 is provided. It can be omitted. Further, since the second pile 112 is provided so as to project at a position higher than the ground level GL or the floor level FL of the lowest floor, it is not necessary to form an underground space for installing the seismic isolation unit 12. Therefore, work such as excavation of earth and sand and discharge of excavated soil becomes unnecessary.

As shown in FIG. 2, a reinforcing beam 114 may be installed between the second piles 112. That is, the reinforcing beams 114 extending in the horizontal direction may be installed between the second piles 112 protruding from the floor of the structure 10 and the second piles 112. The reinforcing beam 114 is joined to a portion of the second pile 112 that projects from the floor of the structure 10. The reinforcing beam 114 is made of, for example, a reinforced concrete structure or a steel frame structure, and is installed between the pile head joints 113 and 113. By providing the reinforcing beam 114, the second pile 112 and the second pile 112 are fixed to each other and the yield strength of the pile head is strengthened. Therefore, even if the second pile 112 is projected from the floor level FL or the ground level GL, it is possible to prevent the strength of the structure 10 from being reduced. Moreover, in addition to the reinforcing beam 114, an earthquake resistant wall may be provided. For example, a seismic wall may be provided between the second pile 112 and the second pile 112 and below the reinforcing beam 114. By providing such an earthquake-resistant wall, the strength of the structure 10 is further suppressed from decreasing in the region where the second pile 112 projects. In addition, in FIG. 1, a reinforcing beam 114 may be installed between the first piles 111. That is, the reinforcing beam 114 may be installed between the pile head joints 113 of the first piles 111 and the pile head joints 113 of the first piles 111 that are adjacent to each other. By providing the reinforcing beam 114, the first pile 111 and the first pile 111 are fixed to each other, and the yield strength of the pile head can be enhanced. Further, in FIG. 2, a reinforcing beam 114 may be installed between a position other than the pile head joint portion 113 and a position other than the pile head joint portion 113. That is, in the second pile 112, in addition to the reinforcement beam 114 between the pile head joints 113, the reinforcement beam 114 is installed between positions other than the pile head joints 113 (for example, intermediate positions of the second pile 112). May be. Further, in the second pile 112, instead of the reinforcing beam 114 between the pile head joints 113, the reinforcing beam 114 is installed between positions other than the pile head joints 113 (for example, intermediate positions of the second pile 112). May be.

In FIG. 1, the protruding length H of the second pile 112 from the floor level or the ground level GL may be, for example, the height of one floor of the structure 10 or may be the height of the middle of the first floor. Specifically, the protrusion length H of the second pile 112 is 800 mm to 6000 mm. By projecting the second pile 112 in this manner, the second pile 112 can be projected by one floor of the structure 10 and can be projected to a height halfway down the first floor.

In the structure 10, the floor space where the second pile 112 projects is provided with a higher floor level than other areas (areas where the second pile 112 does not project). In FIG. 1, the floor level FL of the space 16b in which the second pile 112 does not project is the same height as the ground level GL, but the floor level FL _H of the space 16a in which the second pile 112 projects is the second floor above the ground. It is at the floor level. In this case, the space 16a on the first floor where the second pile 112 projects is not used as a facility. Therefore, the interior work of the space 16a is unnecessary. On the other hand, the space 16b where the second pile 112 does not project is used as a facility such as an office, a store, a warehouse, and a parking lot. In FIG. 1, the case where the space 16b is used as a parking lot is illustrated. Although the space 16b in which the second pile 112 does not project is the internal space of the upper structure 15 in FIG. 1, it may be an external space outside the upper structure 15.

In this way, in the structure 10, by projecting the second pile 112 and providing a high floor level FL _H , damage to the structure 10 is suppressed in the event of a flood or a disaster such as a high tide, a tsunami, or a flood. be able to. Further, by providing the floor level FL _H high, the structure 10 can be effectively used as a physical distribution facility. That is, by providing a part of the first floor as a raised floor, it is possible to match the floor height of the cargo bed of a freight vehicle such as a truck and to smoothly carry in and carry out luggage in the freight vehicle.

In the structure 10, the first pile 111 is provided outside the second pile 112. For example, as shown in FIG. 3, in the construction area R of the structure 10, the first pile 111 is arranged on the outer edge side of the construction area R with respect to the second pile 112. In FIG. 3, the second pile 112 is provided at the center of the construction area R, and the first pile 111 is provided outside the second pile 112. In this way, by providing the first pile 111 and the second pile 112, the space outside the structure 10 can be used as a parking lot or a handling space. That is, the space outside the structure 10 can be used as a parking space for vehicles, and can be used as a space for loading and unloading luggage such as trucks. In addition, in FIG. 3, the second piles 112 are all provided at the center position, but a part of the second piles 112 may be provided at a position outside the construction region R. Further, depending on the structure of the structure 10, the first piles 111 and the second piles 112 may be provided in an installation number other than the number shown in FIG.

In FIG. 1, a seismic isolation unit 12 is provided above the foundation unit 11. That is, the seismic isolation unit 12 is supported and provided by a plurality of foundation piles, and is installed above the first pile 111 and the second pile 112. The seismic isolation part 12 is a part that suppresses the vibration of the structure 10, and a known device using, for example, laminated rubber seismic isolation, rolling seismic isolation, or sliding seismic isolation can be used. Further, it may have a function of absorbing vibration energy by using an oil damper or the like. The seismic isolation unit 12 is provided at the positions of the pile heads 111a and the pile heads 112a of the first pile 111 and the second pile 112. Specifically, the seismic isolation part 12 is installed at the top end of the pile head joint part 113 of the first pile 111 and the second pile 112. The seismic isolation unit 12 exerts a seismic isolation function so that a vibration generated when an earthquake occurs is not transmitted to the upper structure 15. In addition, in FIG. 1, the seismic isolation part 12 is attached on the pile head joint part 113, but when the pile head joint part 113 is not attached to the first pile 111 and the second pile 112, the first pile is attached. The seismic isolation unit 12 may be attached to the top ends of the 111 and the second pile 112.

Next, the workability of the structure 10 in the seismic isolation structure 1 according to the present embodiment will be described.

In FIG. 1, the structure 10 is provided with the second pile 112 projecting upward beyond the ground level GL and the floor level FL on the lowermost floor (the first floor on the ground in FIG. 1 ). The seismic isolation unit 12 is provided on the pile head of the second pile 112. Therefore, even if the seismic isolation part 12 is installed above the ground level GL and the floor level FL on the lowest floor of the structure 10, the seismic isolation part 12 is provided in the area where the second pile 112 projects. There is no need to build pillars for installation. Therefore, the construction cost for constructing the structure 10 can be reduced. Moreover, the construction period for constructing the structure 10 can be shortened.

In the area where the second pile 112 projects, the seismic isolation unit 12 is installed above the ground level GL and the floor level FL, so it is necessary to form an underground space for installing the seismic isolation unit 12. Absent. Therefore, work such as excavation of earth and sand and discharge of excavated soil to form an underground space is unnecessary. Therefore, the construction cost for constructing the structure 10 can be reduced, and the construction period for constructing the structure 10 can be shortened.

On the other hand, if the seismic isolation section 12 is installed below the floor level of the structure 10 when a part of the floor level of the structure 10 is raised to form a high floor structure, in the area of the high floor structure, It is necessary to build pillars even in places that are not used as facilities. Therefore, the construction cost for constructing the structure 10 becomes high, and the construction period of the structure 10 becomes long. In addition, it is necessary to form an underground space for installing the seismic isolation unit 12 in the underground portion of the structure 10. Therefore, work such as excavation of earth and sand and discharge of excavated soil to form an underground space are required. Therefore, the construction cost for constructing the structure 10 becomes high, and the construction period for constructing the structure 10 becomes long. Therefore, in the seismic isolation structure 1 according to the present embodiment, in order to eliminate such inconvenience, the second pile 112 is provided so as to project above the ground level GL or the floor level FL, and is provided above the second pile 112. A seismic isolation unit 12 is installed. Thereby, the construction of the pillar for installing the seismic isolation unit 12 can be omitted. Moreover, the construction of an underground space for installing the seismic isolation unit 12 can be reduced. Therefore, the construction cost of the structure 10 can be reduced and the construction period of the structure 10 can be shortened.

Further, when the seismic isolation unit 12 is provided on the ground floor, it may be possible to provide the seismic isolation unit 12 on the upper part of the pillar constructed on the ground floor. However, if the seismic isolation unit 12 is to be provided in this way, it is necessary to provide a column for installing the seismic isolation unit 12. Therefore, the construction cost for constructing the structure cannot be sufficiently reduced, and the construction period of the structure 10 cannot be sufficiently reduced. In order to eliminate such an inconvenience, the seismic isolation structure 1 according to the present embodiment projects a foundation pile above the ground level GL or the floor level to construct a pillar for installing the seismic isolation part 12. Have reduced. The construction cost of the structure 10 is reduced, and the construction period of the structure 10 is reduced.

By the way, as shown in FIG. 2, in the seismic isolation structure 1, a reinforcing beam 114 is provided above the second pile 112. The reinforcing beam 114 is installed between the second pile 112 and the second pile 112 protruding upward from the floor level, and strengthens the yield strength of the second pile 112. Therefore, even when the second pile 112 is used in place of the pillar of the structure 10, the structure can sufficiently function as the frame of the structure 10.

As described above, according to the seismic isolation structure 1 according to the present embodiment, the plurality of foundation piles include the second pile 112 having the pile head at a position higher than the ground level GL, and the pile heads of the second pile 112 are The seismic isolation unit 12 is also provided at the position. That is, the second pile 112 is provided so as to project upward from the ground level GL, and the seismic isolation unit 12 is provided at the position of the pile head of the second pile 112. Therefore, the seismic isolation unit 12 can be installed without providing a pillar on the upper portion of the second pile 112. Therefore, the construction of columns for installing the seismic isolation unit 12 can be omitted, and the construction period of the structure 10 having the seismic isolation structure can be shortened.

Further, according to the seismic isolation structure 1 according to the present embodiment, the reinforcing beam 114 that extends in the horizontal direction is installed between the second pile 112 having the pile head and the second pile 112 at a position higher than the ground level GL. As a result, the yield strength of the second pile 112 can be improved.

Further, according to the seismic isolation structure 1 according to the present embodiment, the structure 10 is a structure having no basement floor. In this case, when there is a low-rise floor that is not used on the ground floor of the structure 10, the construction of columns for installing the seismic isolation unit 12 on such a low-rise floor can be omitted. Therefore, the construction period of the structure 10 can be shortened.

The present invention has been described above in detail based on the above-described embodiment. However, the present invention is not limited to the above embodiment. The present invention can be variously modified without departing from the scope of the claims.

For example, in the above-described embodiment, as shown in FIG. 2, the seismic isolation unit 12 is installed on the upper portion of the first pile 111 and the second pile 112, but the seismic isolation unit 12 is provided on the reinforcing beam 114. May be. Even in this case, the seismic isolation unit 12 is provided so as to be supported by the plurality of foundation piles via the reinforcing beam 114. Therefore, it is possible to obtain the same effect as that of the above-described embodiment. That is, the seismic isolation part 12 can be installed without providing a pillar on the upper part of the second pile 112. Therefore, the construction of columns for installing the seismic isolation unit 12 can be omitted, and the construction period of the structure 10 having the seismic isolation structure can be shortened.

1... Seismic isolation structure, 10... Structure, 11... Foundation part, 12... Seismic isolation part, 13... Beam, 14... Pillar, 15... Upper structure, 16a... Space, 16b... Space, 111... First pile, 112... Second pile, 113... Pile head joint, 114... Reinforcement beam, FL... Floor level (basic floor level), FL _H ... Floor level (high floor level), R... Construction area.

Claims (4)

In a seismic isolation structure that has a seismic isolation part above the foundation of the structure,
The foundation portion includes a plurality of foundation piles having different pile head heights,
The plurality of foundation piles include foundation piles whose pile heads are located above ground level,
The seismic isolation unit is provided supported by the plurality of foundation piles,
Seismic isolation structure. The seismic isolation unit is provided at the position of the pile head of the plurality of foundation piles,
The seismic isolation structure according to claim 1. The plurality of foundation piles have a plurality of foundation piles whose pile heads are located above the ground level,
A reinforcing beam extending horizontally is installed between the foundation piles in which the pile heads are located higher than the ground level,
The seismic isolation structure according to claim 1. The structure is a structure without a basement,
The seismic isolation structure according to any one of claims 1 to 3.

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