Foundation structure

Abstract

To provide a foundation structure that enables reduction in an amount of concrete used.SOLUTION: A foundation structure 20 formed on the ground comprises: a first foundation portion 21, in an upper structure, supporting a plurality of first columns arranged along a center line A extending in a first direction; and a second foundation portion 22 in an upper structure, supporting a plurality of second columns arranged along a center line B extending in the first direction. The first foundation portion 21 has a width W1 capable of supporting a load from the plurality of first columns in a second direction intersecting with the first direction, and the second foundation portion 22 has a width W2 capable of supporting a load from the plurality of second columns in the second direction.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a foundation structure for a building. [Background technology]

[0002] The foundation structure of a building is selected according to the strength of the ground that supports the building. For example, in the case of a mid-rise or high-rise building, when the ground is strong, a spread foundation such as a slab foundation is used as the foundation structure (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-140972 A Summary of the Invention [Problem to be solved by the invention]

[0004] When a slab foundation is used as the foundation structure, a large amount of concrete is used. In terms of cost and workability, there is a demand to reduce the amount of concrete used in the foundation structure of a building. [Means for solving the problem]

[0005] The foundation structure that solves the above-mentioned problem is a foundation structure formed on the ground, and comprises a first foundation portion in an upper structure supporting a plurality of first columns arranged in a first path extending in a first direction, and a second foundation portion in the upper structure supporting a plurality of second columns arranged in a second path extending in the first direction, wherein the first foundation portion has a width capable of supporting a load from the plurality of first columns in a second direction intersecting the first direction, and the second foundation portion has a width capable of supporting a load from the plurality of second columns in the second direction. Effect of the Invention

[0006] According to the present invention, the amount of concrete used in the foundation structure can be reduced. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a cross-sectional view of a foundation structure of a building. [Diagram 2] FIG. 2 is a plan view of the base structure. [Diagram 3] FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. [Figure 4] FIG. 4 is a cross-sectional view showing a modified example of the base structure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] [Overall structure of the building] An embodiment of the base structure will be described with reference to FIGS. 1, the building 10 includes a foundation structure 20, a frame 30, and a seismic isolation layer 40. The foundation structure 20 is an example of a substructure in the building 10. The frame 30 is an example of a superstructure in the building 10. The seismic isolation layer 40 is located between the foundation structure 20 and the frame 30.

[0009] The foundation structure 20 is formed on the ground 11, which is formed by excavating the surface layer of the earth. The ground 11 supports the building 10. The foundation structure 20 is made of reinforced concrete. The foundation structure 20 supports the frame 30 via the seismic isolation layer 40.

[0010] The frame 30 is formed by joining various steel materials such as H-shaped steel, square steel pipes, and steel plates, for example. The frame 30 is formed of columns 31 and beams 32 connected via joints. Note that the frame 30 is not limited to steel frame construction (S construction), and may be reinforced concrete construction (RC construction), steel reinforced concrete construction (SRC construction), concrete filled steel pipe construction (CFT construction), etc.

[0011] The frame 30 comprises, as columns 31, a plurality of first columns 31A, a plurality of second columns 31B, and a plurality of third columns 31C. The plurality of first columns 31A are arranged along a street center line A. The plurality of second columns 31B are arranged along a street center line B. The plurality of third columns 31C are arranged along a street center line C. The street centers A to C extend along a first direction (see FIG. 2). In FIG. 1, the first direction is the depth direction of the page. Moreover, the street along the street center line A is an example of a first street. The street along the street center line B is an example of a second street.

[0012] The distance D1 between the center line A and the center line B is greater than the distance D2 between the center line B and the center line C. The distance D1 is, for example, a long span of 15 m or more and 25 m or less. The distance D2 is, for example, 5 m or more and 10 m or less. As an example, the distance D1 is more than twice the distance D2.

[0013] The frame 30 includes a first portion 30A and a second portion 30B. The first portion 30A is a portion located between the first column 31A and the second column 31B. The second portion 30B is a portion located between the second column 31B and the third column 31C. In the building 10, a core portion consisting of an elevator, stairs, a machine room, etc. is mainly provided in the second portion 30B. The longitudinal direction of the frame 30 is a first direction, and the lateral direction of the frame 30 is a second direction. The second direction is a direction intersecting with the first direction. The second direction is, for example, perpendicular to the first direction.

[0014] [Fundamental structure] As shown in Fig. 1, the foundation structure 20 includes a first foundation portion 21 and a second foundation portion 22. The first foundation portion 21 and the second foundation portion 22 support each column 31 included in the framework 30. The first foundation portion 21 supports the first column 31A. The second foundation portion 22 supports the second column 31B. Furthermore, the second foundation portion 22 supports the third column 31C via a brace 33.

[0015] As shown in Fig. 2, the first foundation portion 21 and the second foundation portion 22 extend in a first direction. The first foundation portion 21 and the second foundation portion 22 are aligned in a second direction. The first foundation portion 21 is disposed along a center line A. The second foundation portion 22 is disposed along a center line B.

[0016] The foundation structure 20 includes a third foundation portion 23. The third foundation portion 23 extends in the second direction. The third foundation portion 23 connects an end of the first foundation portion 21 and an end of the second foundation portion 22 along the second direction. For example, the foundation structure 20 includes a pair of third foundation portions 23 that connect both ends of the first foundation portion 21 and the second foundation portion 22 to each other.

[0017] The foundation structure 20 includes an intermediate region 24. The intermediate region 24 is located between the first foundation portion 21 and the second foundation portion 22. As an example, the intermediate region 24 is surrounded by the first foundation portion 21, the second foundation portion 22, and a pair of third foundation portions 23.

[0018] No reinforced concrete foundation is placed in the intermediate region 24. For example, a waterproof sheet covering the ground 11 and a concrete floor 24A are provided in the intermediate region 24. The concrete floor 24A is, for example, concrete that is thinner than the reinforced concrete that constitutes the first foundation portion 21, the second foundation portion 22, and the third foundation portion 23. Note that in Fig. 2, the first foundation portion 21, the second foundation portion 22, and the third foundation portion 23 are indicated by thick dots, and the concrete floor 24A provided in the intermediate region 24 is indicated by thin dots.

[0019] 1, the portion of the ground 11 where the first foundation portion 21 is formed, the portion where the second foundation portion 22 is formed, and the portion where the intermediate region 24 is formed are formed by excavating the ground 11 to the same depth. In the intermediate region 24, the ground 11 is covered with a concrete floor 24A.

[0020] [Seismic isolation layer] As shown in FIG. 2, the seismic isolation layer 40 includes a seismic isolation bearing 41 and a seismic isolation damper 42 . The seismic isolation bearing 41 is, for example, a laminated rubber bearing that also functions as a damping material. The seismic isolation bearing 41 may include a lead plug or the like. The first foundation portion 21 and the second foundation portion 22 support the load of the frame 30 via the seismic isolation bearing 41.

[0021] The seismic isolation bearings 41 are disposed directly below each column 31 in the first foundation portion 21 and the second foundation portion 22. In detail, in the first foundation portion 21, the seismic isolation bearings 41 are disposed directly below each first column 31A along the center line A. In the second foundation portion 22, the seismic isolation bearings 41 are disposed directly below each second column 31B along the center line B.

[0022] The seismic isolation damper 42 is a damping material that damps vibrations in the horizontal direction. The seismic isolation damper 42 is, for example, a hydraulic damper. The seismic isolation layer 40 includes, for example, a first seismic isolation damper 42A and a second seismic isolation damper 42B as the seismic isolation dampers 42. The first seismic isolation damper 42A damps vibrations in a first direction. The second seismic isolation damper 42B damps vibrations in a second direction.

[0023] The first seismic isolation dampers 42A are disposed on the first foundation portion 21 and the second foundation portion 22. For example, on the first foundation portion 21, two first seismic isolation dampers 42A are disposed between the seismic isolation bearings 41 along the center line A. Similarly, on the second foundation portion 22, two first seismic isolation dampers 42A are disposed between the seismic isolation bearings 41 along the center line B.

[0024] The second seismic isolation damper 42B is disposed on the third foundation portion 23. For example, in each of the pair of third foundation portions 23, the second seismic isolation damper 42B is disposed between the center lines A and B. Note that a part of the second seismic isolation damper 42B may be located on the first foundation portion 21 or the second foundation portion 22. That is, the second seismic isolation damper 42B may be disposed across the first foundation portion 21 and the third foundation portion 23, may be disposed across the second foundation portion 22 and the third foundation portion 23, or may be disposed across the first foundation portion 21 and the second foundation portion 22.

[0025] 3, the seismic isolation damper 42 connects between the beam 32 located on the first story and the foundation structure 20. For example, the second seismic isolation damper 42B has an upper end connected to the beam 32 located on the first story, and a lower end disposed across the second foundation portion 22 and the third foundation portion 23. The first seismic isolation damper 42A has an upper end connected to the beam 32 located on the first story, and a lower end disposed on the first foundation portion 21 or the second foundation portion 22.

[0026] [Foundation width] The first foundation portion 21 and the second foundation portion 22 are formed by connecting independent foundations that respectively support the columns 31. In detail, the first foundation portion 21 is formed by connecting independent foundations at a plurality of locations, each of which supports one first column 31A. The second foundation portion 22 is formed by connecting independent foundations that support one second column 31B and one third column 31C. Therefore, the widths in the second direction of the first foundation portion 21 and the second foundation portion 22 are determined by the magnitude of the load supported by each foundation portion and the magnitude of eccentric bending that occurs in the seismic isolation bearing 41 and the first seismic isolation damper 42A in each foundation portion.

[0027] 2, for example, the second foundation portion 22 supporting the second pillar 31B and the third pillar 31C supports a larger load than the first foundation portion 21 supporting the first pillar 31A. Therefore, the width W2 of the second foundation portion 22 supporting the second pillar 31B and the third pillar 31C is larger than the width W1 of the first foundation portion 21 supporting the first pillar 31A. In other words, in the second direction, the widths W1 and W2 of the first foundation portion 21 and the second foundation portion 22 have a size that can support at least the load from the pillar 31 supported by each foundation portion.

[0028] The third foundation portion 23 is set to a size capable of supporting the second seismic isolation damper 42B. In detail, the width W3 in the first direction of the third foundation portion 23 is set to a size capable of withstanding the additional bending stress generated by the second seismic isolation damper 42B.

[0029] The width W1 of the first foundation portion 21 and the width W2 of the second foundation portion 22 are larger than the width W3 of the third foundation portion 23. In other words, the first foundation portion 21 and the second foundation portion 22 are connected by the third foundation portion 23, which is thinner (narrower) than the first foundation portion 21 and the second foundation portion 22. Note that as the width W1 of the first foundation portion 21, the width W2 of the second foundation portion 22, and the width W3 of the third foundation portion 23 increase, the intermediate region 24 becomes smaller.

[0030] [Operation of the embodiment] In the foundation structure 20, the load of the frame 30 is supported by a first foundation part 21 that supports the load at the street center A, and a second foundation part 22 that supports the load at the street center B. In the frame 30, since a long span is formed between the street center A and the street center B, the first foundation part 21 and the second foundation part 22 are arranged at a distance from each other, rather than being a full-surface foundation like a slab foundation.

[0031] Also, vibrations in the first direction are damped by the first seismic isolation damper 42A arranged on the first foundation portion 21 and the second foundation portion 22. Furthermore, in order to arrange the second seismic isolation damper 42B that damps vibrations in the second direction, the ends of the first foundation portion 21 and the second foundation portion 22, which are arranged apart from each other, are purposely connected by the third foundation portion 23. Then, vibrations in the second direction are damped by the second seismic isolation damper 42B arranged on the third foundation portion 23.

[0032] In the above foundation structure 20, an intermediate region 24 is formed in an area surrounded by the first foundation portion 21, the second foundation portion 22, and the third foundation portion 23, where no reinforced concrete foundation is provided.

[0033] [Effects of the embodiment] According to the above embodiment, the following effects can be obtained. (1) According to the foundation structure 20, the columns 31 of the frame 30, which is the superstructure, can be supported by the first foundation part 21 and the second foundation part 22. As a result, an intermediate region 24 is formed between the first foundation part 21 and the second foundation part 22, in which no reinforced concrete is provided as a foundation for supporting the load of the superstructure. Therefore, the amount of concrete used to form the foundation can be reduced compared to when the columns 31 of the frame 30 are supported by a mat foundation.

[0034] (2) By disposing the third foundation part 23 between the first foundation part 21 and the second foundation part 22, the second seismic isolation damper 42B can be disposed on the third foundation part 23. Even in this case, the amount of concrete used to form the foundation can be reduced compared to the case where the columns 31 of the frame 30 and the seismic isolation damper 42 are supported by a slab foundation.

[0035] (3) The first foundation portion 21 and the second foundation portion 22 are provided with a first seismic isolation damper 42A that damps vibrations in a first direction, and the third foundation portion 23 is provided with a second seismic isolation damper 42B that damps vibrations in a second direction. As a result, the first seismic isolation damper 42A and the second seismic isolation damper 42B disposed between the foundation structure 20 and the framework 30 can damp both vibrations in the first direction and vibrations in the second direction.

[0036] (4) In the ground 11, the portion where the first foundation portion 21 is formed, the portion where the second foundation portion 22 is formed, and the portion where the intermediate region 24 is formed are excavated to the same depth (see FIG. 1). Therefore, in the intermediate region 24, a space larger vertically is formed between the concrete floor 24A and the beams 32 than between the first foundation portion 21 or the second foundation portion 22 and the beams 32. In other words, a larger space is formed above the concrete floor 24A than when the foundation structure 20 is a slab foundation. This makes it possible to form a space in the intermediate region 24 for arranging an underground pit or the like.

[0037] (5) The first foundation portion 21 and the second foundation portion 22 support the columns 31 of the frame 30 via the seismic isolation bearings 41, which are laminated rubber bearings. This allows the seismic isolation dampers 42 to damp horizontal vibrations, and the laminated rubber bearings to damp vertical vibrations.

[0038] (6) By making the width W3 of the third foundation portion 23 smaller than the width W1 of the first foundation portion 21 and the width W2 of the second foundation portion 22, the intermediate region 24 can be enlarged. This also reduces the amount of concrete used in the foundation structure 20.

[0039] [Example of change] The above embodiment can be modified as follows. The modifications can be combined as appropriate within the scope of the present invention.

[0040] The first foundation portion 21 and the second foundation portion 22 may directly support the columns 31 of the frame 30 without using the seismic isolation bearings 41 . The seismic isolation bearings 41 are not limited to laminated rubber bearings, and may be, for example, sliding bearings. For example, when the seismic isolation layer 40 includes a plurality of seismic isolation bearings 41, one of the seismic isolation bearings 41 may be a laminated rubber bearing, and the other seismic isolation bearings 41 may be a sliding bearing.

[0041] The number of first seismic isolation dampers 42A is not limited to that in the above embodiment, and for example, the first seismic isolation damper 42A may be provided on at least one of the first foundation portion 21 and the second foundation portion 22, or the first seismic isolation damper 42A may be omitted.

[0042] The number of second seismic isolation dampers 42B is not limited to that in the above embodiment, and for example, one of the pair of third foundation portions 23 and the second seismic isolation damper 42B provided on the third foundation portion 23 may be omitted. Moreover, both of the pair of third foundation portions 23 and the second seismic isolation damper 42B provided on the third foundation portion 23 may be omitted.

[0043] As shown in FIG. 4, the depth from the ground surface of the ground 11 may be different between the portion where the first foundation portion 21 is formed, the portion where the second foundation portion 22 is formed, and the portion where the intermediate region 24 located between the first foundation portion 21 and the second foundation portion 22 is formed. For example, in the example of FIG. 4, the depth of the ground 11 is adjusted so that the upper surface of the concrete floor 24A is at the same height as the upper surface of the first foundation portion 21. That is, the portion of the ground 11 where the intermediate region 24 is formed is shallower than the portion where the first foundation portion 21 and the second foundation portion 22 are formed by the difference in thickness between the concrete floor 24A and the first foundation portion 21 and the second foundation portion 22. With this configuration, the amount of excavation (depth) of the portion where the intermediate region 24 is formed can be reduced, thereby improving work efficiency.

[0044] The width W1 of the first foundation portion 21 and the width W2 of the second foundation portion 22 may be large enough to support the load from the column 31 supported by each foundation portion and to withstand eccentric bending occurring in the seismic isolation bearing 41 and the first seismic isolation damper 42A. For example, the width W1 and the width W2 may be equal, or the width W1 may be larger than the width W2. The widths W1 and W2 of the first foundation portion 21 and the second foundation portion 22 and the width W3 of the third foundation portion 23 are not limited, and for example, the width W3 may be equal to either the width W1 or the width W2, or the width W3 may be larger than either the width W1 or the width W2. For example, when the seismic isolation bearing 41 and the first seismic isolation damper 42A are not provided, the width W1 of the first foundation portion 21 and the width W2 of the second foundation portion 22 may be large enough to support at least the load from the column 31 supported by each foundation portion alone.

[0045] The foundation structure 20 may include another foundation part that supports the third column 31C directly below the third column 31C. In this case, the brace 33 is omitted. In this case, the third foundation part 23 may be disposed only between the first foundation part 21 and the second foundation part 22, or the third foundation part 23 may be disposed only between the other foundation part that supports the third column 31C and the second foundation part 22. Also, the third foundation part 23 may be disposed both between the first foundation part 21 and the second foundation part 22 and between the other foundation part that supports the third column 31C and the second foundation part 22.

[0046] The frame 30 may be configured to include only the first pillar 31A and the second pillar 31B, without including the third pillar 31C. The third column 31C may be supported by the second foundation portion 22 without the brace 33. For example, the second foundation portion 22 may be disposed at least from directly below the second column 31B to directly below the third column 31C. And, for example, the second foundation portion 22 may support the second column 31B and the third column 31C via separate seismic isolation bearings 41.

[0047] [Note] According to the above embodiment and its modifications, the following technical ideas can be derived. (Appendix 1) A foundation structure formed on the ground, In the superstructure, a first foundation portion supports a plurality of first columns arranged in a first street extending in a first direction; In the superstructure, a second foundation portion supports a plurality of second columns arranged in a second direction extending in the first direction; A third foundation portion that connects ends of the first foundation portion and the second foundation portion that are arranged in a second direction intersecting the first direction along the second direction, The first foundation portion has a width capable of supporting a load from the plurality of first columns in a second direction intersecting the first direction, The second foundation portion has a width capable of supporting a load from the plurality of second columns in the second direction, A seismic isolation damper is provided on the third foundation portion along the second direction, The width of the third foundation portion in the first direction is smaller than the width of the first foundation portion in the second direction and the width of the second foundation portion in the second direction. Basic structure.

[0048] According to the above-mentioned supplementary note 1, by reducing the width of the third foundation part, it is possible to increase the area between the first foundation part and the second foundation part. This also leads to a reduction in the amount of concrete used in the foundation structure.

[0049] (Appendix 2) A foundation structure formed on the ground, In the superstructure, a first foundation portion supports a plurality of first columns arranged in a first street extending in a first direction; a second base portion supporting a plurality of second columns arranged in a second direction in the superstructure; The first foundation portion has a width capable of supporting a load from the plurality of first columns in a second direction intersecting the first direction, The second foundation portion has a width capable of supporting a load from the plurality of second columns in the second direction, Between the first foundation portion and the second foundation portion, an intermediate region is provided in which a concrete floor thinner than the first foundation portion and the second foundation portion is disposed, In the ground, a portion in which the intermediate region is formed is shallower than a portion in which the first foundation portion is formed and a portion in which the second foundation portion is formed. Basic structure.

[0050] According to the above-mentioned supplementary note 2, the excavation depth of the part of the ground where the intermediate region is to be formed can be reduced, so that the work efficiency can be improved. [Explanation of symbols]

[0051] D1, D2... distance, W1 to W3... width, 10... building, 11... ground, 20... foundation structure, 21... first foundation part, 22... second foundation part, 23... third foundation part, 24... intermediate area, 24A... concrete floor, 30... frame, 30A... first part, 30B... second part, 31... column, 31A... first column, 31B... second column, 31C... third column, 32... beam, 33... brace, 40... seismic isolation layer, 41... seismic isolation bearing, 42... seismic isolation damper, 42A... first seismic isolation damper, 42B... second seismic isolation damper.

Claims

1. A foundation structure formed on the ground, In the superstructure, a first foundation portion supports a plurality of first columns arranged in a first line extending in a first direction; a second base portion supporting a plurality of second columns arranged in a second line extending in the first direction in the superstructure; The first foundation portion has a width capable of supporting a load from the plurality of first columns in a second direction intersecting the first direction, The second foundation portion has a width capable of supporting a load from the plurality of second columns in the second direction. Basic structure.

2. a third foundation portion that connects ends of the first foundation portion and the second foundation portion that are aligned in the second direction along the second direction, A seismic isolation damper is provided on the third foundation portion along the second direction. The base structure of claim 1 .

3. Between the first foundation portion and the second foundation portion, an intermediate region is provided in which a concrete floor having a thickness thinner than that of the first foundation portion and the second foundation portion is disposed, In the ground, a portion where the first foundation portion is formed, a portion where the second foundation portion is formed, and a portion where the intermediate region is formed are at the same depth.

3. The base structure according to claim 1 or 2.

4. The first foundation portion and the second foundation portion support each column of the superstructure via laminated rubber bearings.

3. The base structure according to claim 1 or 2.

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