JP-7854798-B2 - Composite segments and earth retaining structures

Inventors

• 長岡 省吾
• 松岡 馨
• 山本 竜也
• 西山 桂樹

Assignees

• ＪＦＥ建材株式会社

Dates

Publication Date

20260507

Application Date

20211222

Claims (10)

1. A composite segment that is connected in multiple ways in the circumferential and axial directions of the earth retaining structure to construct the earth retaining structure, Steel shell and, The steel shell is filled with concrete, The aforementioned steel shell is A pair of main girders spaced apart in the axial direction, A skin plate joined to the outer periphery of the pair of main girders, A pair of joint plates joined to both ends in the circumferential direction of the pair of main girders, A shape-retaining member joined between the pair of main girders, A reinforcing bar having main reinforcement extending in the circumferential direction and distribution reinforcement extending in the axial direction, Equipped with, The shape-retaining material is It is formed by providing a rectangular notch in the axial center of a rectangular steel plate. The aforementioned reinforcing bars are At least a portion of it is positioned inside the notch and fixed to the shape-retaining material, The earth retaining structure comprises outer reinforcement bars arranged radially outward and inner reinforcement bars arranged radially inward, The main reinforcement and the distribution reinforcement of the inner reinforcement are, They are joined together, The axial end of the aforementioned force distribution reinforcement is The shape-retaining material is bonded to the plate surface, The shape-retaining material is The axial dimension of the notch is The dimension of the steel plate in the axial direction is 6/7, The dimensions at the outer end of the aforementioned notch are, Equal to the radial dimension of the pair of main girders, The radial dimension of the notch is, A composite segment having a radial dimension of 1/4 of the pair of main girders .
2. The aforementioned external reinforcement is, The composite segment according to claim 1, wherein the composite segment is joined to the radial edge of the notch of the shape-retaining material.
3. The radially oriented edge of the notch is The composite segment according to claim 2, which is located outside the center of the radial width of the steel shell.
4. The aforementioned external reinforcement is, The composite segment according to claim 3, which is located outside the center of the radial width of the steel shell.
5. The main reinforcement bars of the outer reinforcement and the inner reinforcement are, The composite segment according to any one of claims 1 to 4, which is connected in the radial direction.
6. The aforementioned reinforcing bars are The aforementioned radially extending radial connecting member is further provided, The radial connecting member is, The composite segment according to claim 5, which connects the main reinforcement bars of the outer reinforcement and the inner reinforcement, respectively.
7. The aforementioned reinforcing bars are The aforementioned radially extending radial connecting member is further provided, The composite segment according to any one of claims 1 to 5, wherein one end of the radial connecting member is connected to the steel shell.
8. The radial connecting member is, The composite segment according to claim 7, which connects the main reinforcement of the inner reinforcement to the skin plate.
9. The radial connecting member is, The composite segment according to claim 7, which connects the distribution reinforcement of the inner reinforcement and the skin plate.
10. A retaining wall structure formed by combining multiple composite segments according to any one of claims 1 to 9 in the circumferential and axial directions.

Description

This invention relates to a composite segment that forms an earth-retaining structure buried underground. Conventionally, the Urban Ring Method (registered trademark) is known as a press-in method for constructing vertical underground structures. The Urban Ring Method involves assembling earth-retaining panels into a ring-shaped structure at the installation site, and then press-injecting the ring-shaped structure into the ground using a press-in device. After the ring-shaped structure is pressed into the ground, the inside of the ring-shaped structure is excavated and the soil removed, and a new ring-shaped structure is added on top. This process is repeated until a predetermined depth is reached, thereby constructing underground structures such as shafts. Another tunnel construction method is the shield tunneling method. The shield tunneling method involves using a tunneling machine installed in a shaft. After excavating a certain length, a segment ring is constructed at the rear of the machine. This ring is then assembled into a ring shape using, for example, arc-shaped composite segments. This ring is then sequentially extended to form a cylindrical lining, thus constructing the shield tunnel. The composite segments used in shafts or tunnels as described above are formed by filling a steel shell with concrete or other filler material. The steel shell has main girders forming the axial end faces of the earth retaining structure, joint plates forming the circumferential end faces, and skin plates forming the outer periphery. By integrally forming the steel shell and the filled concrete, the composite segment ensures strength and rigidity, allowing it to withstand earth pressure from the surrounding ground. Furthermore, because the composite segment is subjected to tensile or compressive stress in the axial direction of the earth retaining structure, a shape-retaining material is provided inside the steel shell in a direction aligned with the axial direction of the earth retaining structure, and is joined between the opposing main girders. The shape-retaining material ensures that the dimensions between the main girders are stably maintained within the steel shell. When shape-retaining members are provided in a composite segment, while the strength and rigidity of the steel shell itself can be ensured, the concrete filling between the shape-retaining members and inside the retaining structure beyond the shape-retaining members will be displaced by the circumferential load on the retaining structure, causing it to bulge inward. Therefore, in Patent Document 1, flanges are projected from each of the pair of main girders in opposing directions to prevent the concrete from shearing, and the concrete is reinforced by placing circumferentially extending reinforcing bars inside the concrete filling located inside the shape-retaining members (see Patent Document 1). Japanese Patent Publication No. 2009-74291 This is a conceptual diagram of the earth retaining structure 200 according to Embodiment 1.This is a conceptual diagram of the segment ring 150 according to Embodiment 1, viewed in the direction AD of the hole axis.This is a perspective view showing an example of a synthetic segment 100 according to Embodiment 1.This is a perspective view showing an example of the internal structure of the synthetic segment 100 according to Embodiment 1.Figure 3 is a perspective view of the composite segment 100 as seen from the outer perimeter of the retaining wall structure 200.This is a schematic diagram of the cross-sectional structure of the composite segment 100 according to Embodiment 1.This is a schematic diagram of a synthetic segment 1000, which is a comparative example of the synthetic segment 100 according to Embodiment 1.This is a schematic diagram of the composite segment 100 according to Embodiment 1.This is a schematic diagram of the cross-sectional structure of the composite segment 101 according to Embodiment 2.This is a schematic diagram of the cross-sectional structure of the composite segment 102 according to Embodiment 3. The earth-retaining structure according to the embodiment will be described below with reference to the drawings. Note that in the following drawings, including Figure 1, the relative dimensions and shapes of the constituent members may differ from those of the actual components. Furthermore, in the following drawings, components with the same reference numerals are identical or equivalent, and this is consistent throughout the entire specification. In addition, terms indicating direction (e.g., up, down, left, right, front, back, front, and back) will be used as appropriate to facilitate understanding; however, these notations are for explanatory convenience and do not limit the arrangement, direction, and orientation of devices, equipment, or parts. Embodiment 1. [Earth retaining structure 200] Figure 1 is a conceptual diagram of an earth retaining structure 200 according to Embodimen