JP2000104482A - Shaft construction method and earth retaining plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To construct a shaft safely and efficiently. SOLUTION: This is a method of constructing a shaft by retaining the inner wall surface by an earth retaining body 20 to form a shaft. The earth retaining body 20 which has the same shape as the flat surface of the shaft and can be formed to be inserted and removed in the shaft excavating direction is arranged in the excavating position of the shaft, and while excavating the inside area of the shaft, the earth retaining body 20 is sunk along the inner wall surface of the shaft to form the shaft. The earth retaining bodies 30, 40 reduced in diameter at the lower stage are used to construct the shaft of a difference in level structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a shaft in an underground civil engineering work or the like and an earth retaining plate used for the method.

[0002]

2. Description of the Related Art In a construction method for underground civil engineering, a starting shaft and a reaching shaft are dug at a starting position and a reaching position of an underground tunnel, respectively, and a tunnel is dug between these shafts. The shaft is dug down to a predetermined depth from the ground, but the inner wall surface is retained with a liner plate so as not to collapse due to earth pressure. The liner plate is formed by forming a steel plate into a corrugated shape and having a high strength so as to withstand the earth pressure.

[0003] The shaft is formed in a planar shape, circular or oval. The liner plates used are divided into arcs or the like in accordance with these shapes, and are connected to each other for earth retaining. For earth retaining work, a liner plate is installed when the shaft is dug to a certain depth, and then the next liner plate is installed by dug to a certain depth.
Adjacent liner plates are fixed by bolts in the circumferential direction and the depth direction to be integrated, and the entire inner wall surface of the shaft is earthed with the liner plate.

[0004]

As described above, in the conventional shaft construction work, the liner plates are sequentially connected in the depth direction while digging the pit by the depth at which the liner plate can be installed, and the predetermined depth is obtained. To form a shaft. When digging a shaft in such a shaft construction work, the wall is not grounded, so the wall may collapse due to earth pressure, making it difficult to work and causing safety problems. there were. In particular, when working at the bottom of a shaft, there is a problem that the work becomes difficult because earth pressure is applied and flooding occurs.

After the shaft has been constructed, it is necessary to remove the liner plate. In this case, the liner plate is removed from the bottom liner plate while removing the bolts in order. This is because the liner plate is formed by forming a steel plate on a spiral surface or a corrugated surface in order to increase strength, so that the liner plate is prevented from falling off in the vertical direction and must be removed in order from the bottom. When the liner plate is removed, the wall surface collapses due to earth pressure, so there is a problem in the removal work in terms of safety and the work becomes complicated.

[0006] In addition, there are various construction works such as deep foundation work other than formation of a shaft, in addition to forming a shaft, and even in these construction works, wall surface collapse due to earth pressure, flooding, etc. There was a problem that efficient work could not be performed. An object of the present invention is to provide a method for constructing a shaft that enables safe and efficient construction when constructing a shaft while retaining such soil, and an earth retaining plate that can be suitably used for the method. And

[0007]

To achieve the above object, the present invention has the following arrangement. That is, in the method of constructing a shaft, in which an inner wall is earthed by an earth retaining body to form a shaft, an earth retaining body formed in the same shape as the plane shape of the shaft so as to be removable in the direction of excavation of the shaft is excavated in the shaft. While digging down the inner area of the shaft,
The earth retaining body is settled along the inner wall surface of the shaft to form a shaft having a height dimension of the earth retaining body. Further, after the inner wall surface is earthed by the earth retaining body to form a shaft, the earth retaining body can be inserted and removed in the direction of excavation of the shaft and has a smaller inner dimension than the earth retaining body, and The earth retaining body is settled while digging down an inner region of the earth retaining body from the bottom, thereby forming a vertical shaft having a step structure in which the inner dimensions gradually decrease from the upper stage to the lower stage. Further, the earth retaining body is obtained by connecting a plurality of panel bodies divided in a circumferential direction.

The earth retaining plate for constructing an earth retaining body which has the same shape as the plane shape of the shaft and can be inserted and removed in the direction of excavation of the shaft, and is divided into a plurality in the circumferential direction in accordance with the plane shape of the shaft. Each of the above-mentioned units is constituted, and at both end edges, a connecting protruding edge bent inside the shaft is provided, and a rib which can be inserted and removed in the direction of excavation of the shaft is provided. Further, the rib is characterized in that an end face shape communicating between an upper end edge and a lower end edge of the earth retaining plate is formed in a V-shape. Further, the earth retaining plate is formed by bending a steel plate into a predetermined shape.

[0009]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 and 2 show the configuration of a retaining plate according to the present invention and a retaining structure constructed by the retaining plate. The earth retaining body of the present embodiment is used when constructing a shaft having a circular plane shape, and is formed by connecting earth retaining plates 10 formed by dividing an arc into six parts using a steel plate and forming an arc shape. It is. FIG. 1 shows a state in which a circular earth retaining body is constructed by connecting earth retaining plates 10, and FIG. 2 shows two earth retaining plates 1.
It is a perspective view of the state which connected 0.

The retaining plate 10 has connecting protruding edges 12 at both end edges.
And a rib 14 having a V-shaped end face at the center in the circumferential direction. The protruding edge 12 and the rib 14 can be formed by bending a steel plate. In the embodiment, both the protruding edge 12 and the rib 14 are formed so as to face the inside of the shaft. The projecting edge 12 is provided with a bolt hole for connecting the retaining plate 10 with a bolt, and the adjacent retaining plate 10 is provided with a bolt hole.
Can be circularly connected by abutting the protruding edges 12 and tightening bolts. The protruding edge 12 has a function of connecting the retaining plate 10 and a function of reinforcing the retaining plate 10.

The ribs 14 are made of the earth retaining plate 10 similarly to the protruding edge 12.
It is provided to reinforce. Earth retaining plate 10 is 2
Since it is formed using a steel plate having a thickness of about 3 mm, it is necessary to provide a rib 14 so as to withstand the earth pressure. The ribs 14 are formed so as to communicate with the vertical direction of the earth retaining plate 10, that is, in the direction of excavation of the shaft, so that the earth retaining body constructed by the earth retaining plate 10 can be easily inserted and removed during the construction of the shaft. To do that. Of course, the shape of the rib 14 is not limited to that of the embodiment, and any shape can be appropriately selected as long as it can be easily inserted and removed. In the embodiment, one rib 14 is formed on one earth retaining plate 10, but a plurality of ribs 14 can be formed. Further, depending on the case, it is also possible to form a part of the upper and lower parts without providing the upper and lower parts.
Further, the shaft may be formed outward instead of being formed inward.

The earth retaining plate 10 is appropriately sized according to the diameter of the shaft. The vertical shaft construction method according to the present invention is characterized in that a plurality of vertical shafts having different diameters are formed. When the diameter of the shaft is different as described above, the retaining plate 10 having a curvature corresponding to the diameter of the shaft is used.
The height dimension of the earth retaining plate 10 is appropriately 2 mm, 4 m, or the like depending on the depth of the shaft or the like. The number of divisions when the earth retaining body is divided into a plurality of earth retaining plates 10 is not particularly limited, and the earth retaining body is divided into four, six, eight, and the like.

3 to 5 show a construction method for constructing a retaining body by the retaining plate 10 to form a shaft. FIG. 3 shows a state in which a shaft is dug using the earth retaining body 20 formed by connecting the earth retaining plates 10 in a circular shape, and the inner wall surface of the shaft is protected by the earth retaining body 20. The earth retaining body 20 of the embodiment has an inner diameter of 2 m.
It is 80 cm in height and 2 m in height. When digging a shaft using the earth retaining body 20, first place the earth retaining body 20 in accordance with the pit position where the shaft was dug to a depth of about 10 cm,
The earth retaining body 20 is sunk while digging little by little. Since the earth retaining body 20 has a shape that allows easy insertion and removal,
By lowering the earth retaining body 20 while deepening the pit, it becomes possible to dig while the inner wall surface of the shaft is protected by the earth retaining body 20.

FIG. 3 shows a state in which the shaft is dug to the height of the retaining body 20 and the entire retaining body 20 is sunk. In this state, the upper flange 22 is fixed to the upper edge of the earth retaining body 20, and the earth retaining body 20 is fixed in the height direction. Next, in order to further excavate the shaft in the depth direction, the second shaft is dug from the bottom of the first shaft using the earth retaining body 30 having a smaller diameter than the earth retaining body 20. FIG. 4 shows a state in which the inner wall surface of the second shaft is protected by the earth retaining body 30.

The earth retaining body 30 used in the second stage shaft
Similarly to the earth retaining body 20, the earth retaining plates 10 are connected to each other to form a circular shape in a plan view. In the case of forming the second shaft, the shaft is dug while the earth retaining body 30 is lowered from the bottom of the first shaft. In this way, even when forming the second shaft, it is possible to excavate while retaining the inner wall surface of the shaft with the retaining body 30. The earth retaining body 30 used in the second shaft in the embodiment has an inner diameter of 2 mm.
m40 cm, height 2 m.

FIG. 4 shows that the first and second shafts are earth retaining bodies 2.
0 and the earth retaining body 30 holds the earth. As shown in FIG. 5, the first step and the second step are formed on the bottom flange 24 fixed to the lower edge of the first step earth retaining body 20 and on the second step earth retaining body 30. Combining the upper flange 22 fixed to the edge, the earth retaining body 3
0 is supported so as not to sink, and is covered so that the soil is not exposed.

It is not always necessary to combine the bottom flange 24 and the upper flange 22 at the step portion of the shaft, but groundwater or muddy water may enter the shaft from the step portion, or soil may enter the shaft by earth pressure. May be pushed out, so it is preferable to close the step.

FIG. 6 shows a state in which a third-stage shaft is dug from the bottom of the second-stage shaft using the earth retaining body 40.
In the embodiment, the soil retaining body 40 has an inner diameter of 2 m and a height of 2 m.
m. The method of digging the shaft using the earth retaining body 40 is the same as that of the first and second steps. By digging while sinking the earth retaining body 40, it is possible to work with the inner wall surface of the shaft being earthed, and to work safely and efficiently. In the present embodiment, the process proceeds to the formation of the horizontal shaft at the place where the third shaft is dug.

FIG. 7 is a plan view showing a state where a shaft is dug using the earth retaining members 20, 30, and 40. Earth retaining body 20, 3
0 and 40 are arranged concentrically and gradually reduced in diameter from the top. Since the diameter of the shaft is gradually reduced from the upper stage, the earth retaining used in each stage is selected so that the required inner diameter of the shaft is obtained. In the above embodiment, the shaft has a depth of 6 m. For example, when it is necessary to form a shaft having a depth of 8 m, the suspended earth retaining body 30 is formed by the earth retaining plate 10 having a height of 4 m. It is necessary to use. Further, it is also possible to form a deeper shaft by extending the earth retaining material further down.

As described above, in the shaft construction method of the present embodiment, the earth retaining body 2 in which the earth retaining plates 10 are circularly connected.
Using 0, 30, and 40, the digging is performed while retaining the inner wall surface of the shaft with the retaining plate 10, so that it is extremely safe even when working inside the pit. In addition, since the wall is dug down while retaining the soil, it is possible to efficiently work without collapsing the wall surface.

In the case where the required retaining work or the like is completed and the earth retaining bodies 20, 30, 40 are to be removed, the earth retaining bodies 20, 30, 40 can be easily removed by sequentially pulling them upward from the lower earth retaining body 40. . Since the earth retaining bodies 20, 30, and 40 have a structure that can be easily inserted and removed, the earth retaining bodies 20, 30, and 40 can be easily removed simply by pulling up the earth retaining bodies 20, 30, and 40 using the lifting device. In this removal work, the work in the mine is only required to remove the connecting portion of each step, and the work such as removing the liner plate remaining in the mine becomes unnecessary. As a result, the work of removing the earth retaining material can be performed extremely safely. In addition, since the earth retaining can be easily removed, the earth retaining has to be buried as it is, and the earth retaining plate 10 can be reused.

In the above embodiment, an example was described in which a circular retaining plate was constructed by combining retaining plates.
When the vertical shape of the shaft is an oval shape, it is possible to construct an oval-shaped retaining wall using a retaining plate obtained by dividing the oval shape, and to similarly construct the shaft. When using an oval-shaped earth retaining material, it is only necessary to gradually dig down a pit using a small-diameter earth retaining material from the upper stage to the lower stage.

In the above embodiment, the earth retaining plate 10 for constructing the earth retaining body has a shape that completely covers the inner wall surface of the shaft. If you work while
The retaining plate 10 may be provided with holes for flooding. The material of the earth retaining plate 10 may be appropriately selected in consideration of earth pressure, durability and the like. Further, the method for constructing a shaft according to the present invention is not limited to the case of constructing a shaft, but can be similarly applied to civil engineering work of the same form when a shaft is constructed such as deep foundation work. The construction of a shaft according to the present invention means such civil engineering work.

[0024]

According to the vertical shaft construction method of the present invention,
As described above, since the operation can be performed with the inner wall surface of the shaft being earthed by the earth retaining body, the shaft construction work can be performed safely and efficiently. Moreover, since the removal work of the earth retaining body can be performed safely and efficiently, it can be widely used as a method of constructing a shaft. In addition, by using the earth retaining plate according to the present invention, the earth retaining body can be easily constructed, and since the structure is simple, the production of the earth retaining plate is easy, so that significant effects are exhibited. .

[Brief description of the drawings]

FIG. 1 is a plan view of an embodiment of an earth retaining body according to the present invention.

FIG. 2 is a perspective view showing a state in which earth retaining plates are connected.

FIG. 3 is a cross-sectional view of a state where the first stage of a shaft has been constructed using a retaining body.

FIG. 4 is a cross-sectional view of a state where the second stage of the shaft has been constructed using an earth retaining body.

FIG. 5 is a sectional view showing a configuration of a step portion of a shaft.

FIG. 6 is a cross-sectional view of a state where the third stage of the shaft has been constructed using the earth retaining body.

FIG. 7 is a plan view showing a state where a shaft has been constructed using an earth retaining body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Earth retaining plate 12 Protrusion edge 14 Rib 20, 30, 40 Earth retaining body 22 Top flange 24 Bottom flange

Claims (6)

[Claims] 1. A method for constructing a shaft in which an inner wall surface is earthed by an earth retaining body to form a shaft, wherein the earth retaining body is formed in the same shape as a plane shape of the shaft so as to be able to be inserted and removed in a direction in which the shaft is excavated. It is arranged at the excavation position of the shaft, and while digging down the inner area of the shaft, the earth retaining body is settled along the inner wall surface of the shaft, thereby forming a shaft having a height dimension of the earth retaining body. Shaft construction method. 2. After the inner wall surface has been earthed by the earth retaining body to form a shaft, the earth retaining body can be inserted and removed in the direction of excavation of the shaft and has a smaller inner size than the earth retaining body. The pit having a step structure in which the inner dimensions gradually decrease from the upper tier to the lower tier by forming the earth retaining body while sinking down the inner region of the earth retaining body from the bottom of the shaft. A method for constructing a shaft according to item 1. 3. The method for constructing a shaft according to claim 1, wherein said earth retaining body is formed by connecting a plurality of panel bodies divided in a circumferential direction. 4. An earth retaining plate for constructing an earth retaining body having the same shape as the plane shape of a shaft and capable of being inserted and removed in the direction of excavation of the shaft, wherein the earth retaining plate is divided into a plurality in the circumferential direction according to the plane shape of the shaft. An earth retaining plate, wherein each of the above-mentioned units is formed, and a rib for connection is provided on both ends of the shaft so as to bend inside the shaft, and a rib which can be inserted and removed in the direction of excavation of the shaft is provided. 5. The retaining plate according to claim 4, wherein the rib has a V-shaped end face communicating between an upper edge and a lower edge of the retaining plate. 6. The retaining plate according to claim 4, wherein the retaining plate is formed by bending a steel plate into a predetermined shape.