Building structure
The innovative use of interlocking members and buffer materials in building structures with steel pipe piles and concrete foundations addresses the issue of increased bending moments, reducing costs by enabling smaller pipe diameters and thinner foundations.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- OHBAYASHI GUMI LTD
- Filing Date
- 2024-11-15
- Publication Date
- 2026-05-27
AI Technical Summary
The conventional building structure with steel pipe piles and concrete foundations experiences increased bending moments at the pile head due to horizontal loads, necessitating larger and more costly structures to withstand earthquakes.
A building structure design featuring steel pipe piles with interlocking members and buffer materials softer than concrete, separating the steel pipe piles from the concrete foundation, reducing direct load transmission and bending moments.
This design reduces bending moments at the pile head, allowing for smaller steel pipe piles and thinner concrete foundations, thereby lowering construction costs while maintaining structural integrity.
Smart Images
Figure 2026087414000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a building structure having steel pipe piles provided in the ground and a concrete foundation provided on the steel pipe piles.
Background Art
[0002] Conventionally, as a building structure, one having steel pipe piles provided in the ground and a concrete foundation provided on the steel pipe piles is known (see, for example, Patent Document 1).
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] In the above conventional building structure, a plurality of reinforcing bars protruding upward from the pile head are joined to the steel pipe pile, and these reinforcing bars are connected to the concrete foundation, so that the steel pipe pile is rigidly joined to the concrete foundation. Therefore, when a horizontal load is applied to the building during an earthquake or the like, there is a problem that the bending moment of the pile head transmitted from the steel pipe pile to the concrete foundation increases.
[0005] When the bending moment of the pile head transmitted from the steel pipe pile to the concrete foundation increases, in order to cope with this, it is necessary to make the steel pipe pile and the concrete foundation into a larger structure with higher strength, and accordingly, the cost of the building structure increases.
[0006] The present invention has been made in view of the above problems, and an object thereof is to provide a building structure capable of reducing the bending moment of the pile head transmitted from the steel pipe pile to the concrete foundation.
Means for Solving the Problems
[0007] The underground structure of the building of the present invention is characterized by comprising: a steel pipe pile installed in the ground; a concrete foundation installed on the steel pipe pile; an interlocking member having three or more plate sections arranged radially around the axis of the steel pipe pile, each of which is joined to the steel pipe pile at each plate section and embedded in the concrete foundation; and a plurality of buffer materials, each made of a material softer than concrete, provided between adjacent pairs of plate sections and between the steel pipe pile and the concrete foundation to separate the steel pipe pile and the concrete foundation.
[0008] In the underground structure of the building of the present invention, it is preferable that concrete is filled inside the steel pipe piles. [Effects of the Invention]
[0009] According to the present invention, it is possible to provide a building structure that can reduce the bending moment at the pile head transmitted from the steel pipe pile to the concrete foundation. [Brief explanation of the drawing]
[0010] [Figure 1] This is a cross-sectional view of a key part of the structure of a building according to one embodiment of the present invention. [Figure 2] This is a cross-sectional view along line AA in Figure 1. [Figure 3] This is a cross-sectional view along line BB in Figure 1. [Modes for carrying out the invention]
[0011] The following describes in detail the structure of a building according to one embodiment of the present invention, with reference to the drawings.
[0012] As shown in Figure 1, the building structure 1 includes steel pipe piles 10, a concrete foundation 20, a splice member 30, and a plurality of buffer materials 40.
[0013] In this embodiment, the building structure 1 is an underground structure created by excavating the ground 2. However, the building structure 1 is not limited to an underground structure.
[0014] As shown in Figures 1 and 2, the steel pipe pile 10 is formed from a steel pipe with a circular cross-section and is installed underground by being driven into a pile hole 11 made in the ground 2. The building structure 1 according to this embodiment has multiple steel pipe piles 10, but for convenience, only one steel pipe pile 10 is shown in Figures 1 and 2.
[0015] The steel pipe pile 10 is entirely positioned inside the pile hole 11, and its upper end 12 is at the same height as the bottom surface 2a of the ground 2. In this embodiment, the inside of the steel pipe pile 10 is filled with concrete 13. In other words, in this embodiment, the steel pipe pile 10 is formed from a concrete-filled steel pipe.
[0016] The number of steel pipe piles 10 provided in the building structure 1 is not particularly limited. Furthermore, the steel pipe piles 10 may not have concrete 13 filled inside.
[0017] The concrete foundation 20 is constructed by pouring concrete onto the bottom surface 2a of the ground 2 and is placed on top of the steel pipe piles 10. Although not shown in detail, the concrete foundation 20 is made of reinforced concrete with reinforcing bars arranged inside. The reinforcing bars in the concrete foundation 20 are located only inside the concrete foundation 20 and do not protrude toward the steel pipe piles 10.
[0018] The concrete foundation 20 may have a configuration that includes a foundation beam portion 21. In this embodiment, the foundation beam portion 21 of the concrete foundation 20 is positioned on top of the steel pipe pile 10.
[0019] The interrupt member 30 includes four plate portions 31 arranged radially around the axis O of the steel pipe pile 10, and has a cross-shaped cross section perpendicular to the vertical direction. The four plate portions 31 are each in the shape of a rectangular plate. In order to join the interrupt member 30, the steel pipe pile 10 is provided with four slits 14 that extend downward from the upper end 12 of the steel pipe pile 10 and are arranged at equal intervals in the circumferential direction. The width of each slit 14 is a width corresponding to the thickness of the plate portion 31. Also, the vertical length of each slit 14 is shorter than the vertical length of the interrupt member 30. The four plate portions 31 are each inserted into the corresponding slit 14, and the portions protruding radially outward from the slit 14 are welded to the outer peripheral surface of the steel pipe pile 10. Thus, the interrupt member 30 is joined to the steel pipe pile 10 at the four plate portions 31. Note that the second moment of area of the interrupt member 30 is smaller than the second moment of area of the steel pipe pile 10.
[0020] On the other hand, the upper portion of the interrupt member 30, that is, the upper portions of the four plate portions 31, each protrude upward from the upper end 12 of the steel pipe pile 10 and are embedded in the concrete foundation 20. A plurality of studs 32 are fixed to the portions of the four plate portions 31 embedded in the concrete foundation 20. In FIG. 1, for the sake of convenience, only some of the studs 32 are labeled. By fixing the plurality of studs 32, the four plate portions 31 are prevented from coming off with respect to the concrete foundation 20. Thereby, the axial force from the concrete foundation 20 is transmitted from the interrupt member 30 to the steel pipe pile 10 via the plurality of studs 32.
[0021] The interrupt member 30 is not limited to the configuration in which the number of plate portions 31 is four as long as it has three or more plate portions 31 arranged radially around the axis O.
[0022] The plurality of cushioning materials 40 are each formed of a member softer than concrete, and as shown in FIGS. 1 and 3, are provided between the steel pipe pile 10 and the concrete foundation 20 between a pair of adjacent plate portions 31 to separate the steel pipe pile 10 and the concrete foundation 20.
[0023] More specifically, each cushioning material 40 is formed in a fan-shaped plate shape having an arc-shaped outer peripheral edge with the same diameter as the outer diameter of the steel pipe pile 10, and is disposed on the upper end 12 of the steel pipe pile 10 and on the concrete 13 between a pair of adjacent plate portions 31 to cover the entire part other than the portion where the cut-in member 30 protrudes. These cushioning materials 40 are disposed inside the pile hole 11 and contact the lower surface 22 of the concrete foundation 20 on their upper surfaces.
[0024] Each cushioning material 40 can be easily provided between the steel pipe pile 10 and the concrete foundation 20 by being disposed on the upper end 12 of the steel pipe pile 10 after the steel pipe pile 10 joined with the cut-in member 30 is driven into the pile hole 11 and before the concrete for forming the concrete foundation 20 is placed on the bottom surface 2a of the ground 2.
[0025] Each cushioning material 40 is preferably softer than concrete and has a strength or hardness sufficient to support the weight of the concrete for forming the concrete foundation 20. In the present embodiment, the cushioning material 40 is made of expanded polystyrene that satisfies the above conditions. More specifically, the cushioning material 40 is formed of Styrofoam (registered trademark).
[0026] Note that the cushioning material 40 is not limited to being made of expanded polystyrene, and may be formed of various members as long as they are members softer than concrete.
[0027] The steel pipe pile 10 and the concrete foundation 20 are separated from each other by the presence of a buffer material 40 between them, preventing them from becoming one. As a result, the steel pipe pile 10 and the concrete foundation 20 are connected to each other only by the interlocking member 30 joined to the steel pipe pile 10. Therefore, when a horizontal load is applied to the building structure 1, such as during an earthquake, the horizontal load is not applied directly to the pile head of the steel pipe pile 10, but rather to the interlocking member 30 supported by the steel pipe pile 10. Furthermore, even if the concrete foundation 20 moves downward toward the upper end 12 of the steel pipe pile 10 when a horizontal load is applied to the building structure 1, the load from this movement is not transmitted to the steel pipe pile 10 because the respective buffer materials 40 are compressed.
[0028] Thus, in the building structure 1 according to this embodiment, the interlocking member 30 joined to the steel pipe pile 10 is embedded in the concrete foundation 20, and a plurality of buffer materials 40 made of a material softer than concrete are provided between the steel pipe pile 10 and the concrete foundation 20, thereby separating the steel pipe pile 10 and the concrete foundation 20. As a result, the cross-sectional performance of the pile head of the steel pipe pile 10 can be determined solely by the cross-section of the interlocking member 30 joined to the steel pipe pile 10. This reduces the bending rigidity of the pile head of the steel pipe pile 10, and when a horizontal load is applied to the building structure 1, such as during an earthquake, the bending moment of the pile head transmitted from the steel pipe pile 10 to the concrete foundation 20 can be reduced.
[0029] Furthermore, when a horizontal load is applied to the building structure 1, the bending moment at the pile head transmitted from the steel pipe pile 10 to the concrete foundation 20 can be reduced. As a result, the cost of the building structure 1 can be reduced by decreasing the diameter of the steel pipe pile 10 or by reducing the thickness of the concrete foundation 20.
[0030] The present invention is not limited to the embodiments described above, and it goes without saying that various modifications are possible without departing from the spirit of the invention. [Explanation of Symbols]
[0031] 1. Building structure 2 Ground 2a Bottom 10 Steel pipe pile 11 Pile holes 12 Top 13 Concrete 14 slits 20 Concrete foundation 21 Foundation beam section 22 Bottom side 30 Interlocking members 31 Plate section 32 studs 40 Cushioning material O axis
Claims
1. Steel pipe piles installed underground, A concrete foundation is provided on top of the aforementioned steel pipe pile, An interlocking member comprising three or more plate portions arranged radially around the axis of the steel pipe pile, wherein each of the plate portions is joined to the steel pipe pile and embedded in the concrete foundation, A building structure characterized by having a plurality of buffer materials, each formed from a material softer than concrete, provided between a pair of adjacent plate portions and between the steel pipe pile and the concrete foundation to separate the steel pipe pile and the concrete foundation.
2. The building structure according to claim 1, wherein concrete is filled inside the steel pipe pile.