JP3289654B2 - Entrance device of shield machine in shaft and method of starting shield machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a construction method for directly cutting and starting a retaining wall of a shaft by a shield machine, and is intended to prevent earth and sand and groundwater from flowing into the shaft when the shield machine penetrates the retaining wall. Entrance device and sheet to prevent
This is related to the method of starting the aircraft .

[0002]

2. Description of the Related Art In the shield method, it is common to improve the ground on the front side of a shield machine in the starting direction outside the earth retaining wall of a shaft, then make a hole in the earth retaining wall of the shaft, and start from there. However, such a starting method requires a cost and a construction period for ground improvement, and in recent years, a construction method of directly cutting the earth retaining wall of the shaft with a cutter of a shield machine and starting is carried out. In this case, a special member is buried only in the portion of the earth retaining wall of the shaft corresponding to the entrance of the shield machine (for example, NOMST method, etc .: Novet method).
l Material Shield-cuttable Tunnel-wall System),
Alternatively, a treatment such as plain concrete is performed.

[0003] In such a construction method, when a shield machine cuts and penetrates the earth retaining wall, a waterproofing device called an entrance is provided around the cut portion of the earth retaining wall in order to prevent earth and sand or groundwater from flowing into the shaft from a gap. (Entrance packing) is provided. Entrance in the general shield method is often provided with a wellhead for starting on the retaining wall in advance, and packing is directly attached to the edge, but NOMS
In the T method and the like, in order to directly cut the earth retaining wall, as shown in FIG. 3, a cylindrical frame 2 which is slightly larger than the outer diameter of the shield machine 1 is fixed inside the earth retaining wall B of the shaft A, and as shown in FIG. A seal member (water-tight packing) 3 such as a rubber sheet is attached to the inner surface of the frame 2 in a ring shape. Note that a special member B ′ is embedded in a portion of the earth retaining wall B (RC underground continuous wall) that penetrates the shield machine 1. C indicates the range of the ground improvement that has become unnecessary.

[0004]

In the conventional entrance such as the NOMST method, as shown in FIGS. 2 (b) and 3, a seal is attached to the cutter disk 1a of the shield machine 1 which rotates when the retaining wall B is cut. In order to prevent the members 3 (usually two steps) from coming into contact with each other, the seal members 3 are attached to the cylindrical frame 2 such that the seal members 3 are located behind the cutter disk 1a when the shield machine 1 is set. Therefore, the entire entrance has a structure that is long in the direction of the axis of rotation of the shield machine, and when the depth of the shaft A cannot be obtained, obstacles such as the inability to assemble the shield machine occur.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to directly cut and start a retaining wall of a shaft to prevent inflow of earth and sand or groundwater into the shaft. , An entrance device and a shield machine that can have a compact structure with a short size in the rotation axis direction while maintaining sufficient water shielding performance
To get the start method .

[0006]

According to a first aspect of the present invention, there is provided a cylindrical frame provided with a sealing member of a shield machine on an inner surface inside a retaining wall of a shaft, and a shield inserted into the cylindrical frame. In an entrance device for cutting the earth wall by a machine and starting a shield machine, the tubular frame is composed of an outer frame and an inner frame, and the outer frame is fixed inside the earth wall of the shaft, and The inner frame can be slid in the direction of the rotation axis of the shield machine, and the seal
It is inserted so that it can be impervious to the material, and the seal member of the shield machine is installed on the inner surface of the inner frame,
The actuator located on the outside allows the inner frame
The outer frame by sliding the
Inside the outer frame and the inner frame inside the outer frame.
Is extended to the rear of the shield machine so that the inner frame
The inner sealing member is behind the cutter disk of the shield machine.
This is an entrance device for a shield machine in a shaft, wherein the entrance device is configured to be located at a side .

According to a second aspect of the present invention, the inside of the earth retaining wall of the shaft is provided.
In addition, a cylindrical frame equipped with a sealing member of the shield machine on the inner surface
The shield machine inserted into this cylindrical frame
Start to cut the earth retaining wall and start the shield machine
In the method, the tubular frame is connected to an outer frame.
Consists of an inner frame and an outer frame and inner
A seal member is provided between the inner frame and the inner
-Install a shield member for the shield machine on the inner surface of the
Secure the outer frame inside the retaining wall of the shaft,
The inner frame is stored in the outer frame
Then, in this storage state, assemble the shield machine and
And then seal the inner frame.
The shield machine in this extended state.
Launching shield machines in shafts
It is a hexadecimal method.

An actuator such as a jack is used to slide the inner frame. The base of the actuator is fixed to the inner wall of the retaining wall of the shaft, and the tip is attached to the inner frame. This actuator may be disposed at about four locations on the outer periphery of the inner frame. The gap between the inner frame and the outer frame may be sealed with a mechanical seal or the like capable of sufficiently supporting the inner frame while slidably supporting the inner frame. Also, at the time of assembling the entrance, since the water blocking performance is not yet required, the gap between the inner frame and the outer frame is left as it is at the time of assembling the entrance, and after assembly, processing such as water stop welding is performed. Is also good.

In the above configuration, when assembling the shield machine in the shaft, the inner frame is inserted into the outer frame with a jack or the like and housed. As a result, the length of the cylindrical frame in the direction of the axis of rotation of the shield machine is significantly shorter than that of the conventional cylindrical frame. When the start of the shield machine is completed after the assembly of the shield machine is completed, the inner frame is extended from the outer frame to the rear of the shield machine (in the anti-start direction) with a jack or the like. Thereby, located behind the cutter disc seal member starvation Rudo machine inner frame inner surface, also the outer frame and the gap of the inner frame is water-impervious in a mechanical seal or the like, upon earth retaining wall cutting through the shield machine, sand Ya Groundwater is completely prevented from flowing into the shaft.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings. FIG. 1 is a schematic sectional view showing an example in which the entrance device of the present invention is applied to a shield machine having a general circular section. FIG. 2 is a schematic cross-sectional view showing an operation state of a similar entrance device together with a conventional entrance device.

In FIG. 1, the entrance device of the present invention has a cylindrical frame 2 having a double structure of an outer frame 4 and an inner frame 5, and the inner frame 5 is fixed to the outer frame 4 by a hydraulic jack 6 by a shield machine rotating shaft. , And a ring-shaped seal member 7 is attached to the inner surface of the inner frame 5 in two steps, for example.
A mechanical seal 8 is provided between the outer frame 4 and the inner frame 5.

The outer frame 4 is a cylindrical member having an inner diameter capable of housing the inner frame 5 via a mechanical seal 8 and is fixed inside the retaining wall B of the shaft A so as to cover the entrance of the shield machine. Inner frame 5
Is a cylindrical member having an inner diameter slightly larger than the outer diameter of the shield machine 1, inserted into the outer frame 4, and supported by a mechanical seal 8 so as to be slidable in the shield machine rotation axis direction and water-blocking. I have. The length of the inner frame 5 is longer than the length of the outer frame 4, and the distal end of the inner frame 5 projects from the outer frame 4 in the inserted state.

The hydraulic jack 6 has a cylinder base fixed to the inner wall of the retaining wall B. A mounting member 9 is fixed to the outer surface of the distal end of the inner frame 5, and the rod distal end of the hydraulic jack 6 is connected to the distal end of the mounting member 9 via a pin 10 so that the inner frame 5 can slide smoothly. I have.

The seal member (water-tight packing) 7 is positioned such that the inner frame 5 extends rearward so as to be located behind the cutter disc 1a.
It is attached to the rear of the inner surface of the. The shape and the like of the sealing member 7 may be the same as those in the related art. For example, a pair of rubber sheets whose inner peripheral portions are pressed against the skin plate 1b of the shielding machine 1 are arranged at intervals in the rotation direction of the shielding machine. And
It is fixed to the inner surface of the inner frame 5 by the fixing member 11.

The entrance device having the above configuration is
It is applied to the NOMST method that starts by directly cutting the earth retaining wall, and operates as follows. In addition, a special member is buried in the portion corresponding to the entrance of the shield machine of the earth retaining wall, or plain concrete or the like is constructed.

(1) At the time of installation of the shield machine As shown in FIG. 2 (a-1), the outer frame 4 and the hydraulic jack 6 are fixed to the inner wall of the retaining wall B, and the rod of the hydraulic jack 6 is contracted. Then, the inner frame 5 is stored in the outer frame 4. In this state, the shield machine 1 is assembled and set in the inner frame 5. The overall length of the entrance device is approximately half that of a conventional entrance, so that the space of the shaft A can be widely used or the diameter of the shaft A can be reduced.

(2) At the start of cutting the retaining wall by the shield machine As shown in FIG. 2 (a-2), the rod of the hydraulic jack 6 is extended to extend the inner frame 5 toward the rear of the shield machine 1. Let out. The overall length of the entrance device is the same as the length of the conventional entrance and the sealing member 7
Is located behind the cutter disk 1a. From this state, the retaining wall B is directly excavated with the cutter disk 1a and started. Even if the shield machine 1 excavates and penetrates the retaining wall B, and the earth and sand or groundwater flows in from the gap, the sealing member 7 can surely prevent the intrusion.

In the above embodiment, an example in which the present invention is applied to a shield machine having a circular cross section has been described. However, it is needless to say that the entrance apparatus of the present invention can be applied to a shield machine having an irregular cross section. . In this case,
What is necessary is just to change the shape of a frame etc.

[0019]

As described above, according to the present invention, the tubular frame fixed to the inner wall of the retaining wall of the shaft has a double structure of the outer frame and the inner frame, and the outer frame is fixed to the inner side of the retaining wall. Since the inner frame is inserted into the frame so as to be slidable in the direction of the rotation axis of the shield machine and water-tight, and the seal member of the shield machine is provided on the inner surface of the inner frame, the following effects can be obtained. .

(1) Compared with a conventional entrance, the size of the entire apparatus at the time of installation of the shield machine can be greatly reduced in the direction of the rotation axis of the shield machine. Therefore, the space in the shaft can be widened, and the time and cost required for assembling and installing the shield machine can be reduced. Further, since the diameter of the shaft can be reduced, there are merits such as a reduction in construction cost and a reduction in land required for the shaft construction.

(2) At the beginning of cutting the earth retaining wall of the shield machine,
It has the same size as the conventional entrance, and it can reliably prevent earth and sand and groundwater from flowing into the shaft.
The present invention can be applied to a construction method in which the earth retaining wall is directly cut without starting the ground without starting the soil improvement, and in combination with the above-described reduction in the size of the device, a great reduction in cost and a reduction in the construction period can be achieved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of an entrance device of the present invention.

2 (a) is a schematic sectional view showing an operation state of the entrance device of FIG. 1, and FIG. 2 (b) is a schematic sectional view of a conventional entrance.

FIG. 3 is a schematic cross-sectional view showing a NOMST method using a conventional entras.

[Explanation of symbols]

 A: Vertical shaft B: Retaining wall B ': Special member 1: Shielding machine 1a: Cutter disk 1b: Skin plate 2: Cylindrical frame 3: Seal member 4: Outer frame 5: Inner frame 6: ... Hydraulic jack 7 ... Seal member 8 ... Mechanical seal 9 ... Mounting member 10 ... Pin 11 ... Fixing member

Continuation of the front page (56) References JP-A-9-165992 (JP, A) JP-B-51-11404 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21D 9 / 06 301

Claims (2)

(57) [Claims] A tubular frame having a sealing member for a shield machine on its inner surface is provided inside a retaining wall of a shaft, and the shield machine is cut by the shield machine inserted into the tubular frame to form a shield machine. In the entrance device to be started, the tubular frame is composed of an outer frame and an inner frame, the outer frame is fixed inside a retaining wall of a shaft, and the inner frame is slid in the outer frame in the axial direction of the shield machine. capable, <br/> one or, seepage control capable inserted by a sealing member, provided a sealing member shields machine the inner surface of the inner frame, outer
The actuator located outside the frame allows
The outer frame by sliding the
Stored in the outer frame and the inner frame in the outer frame.
-Extend the frame to the rear of the shield machine and
-The sealing member on the inner surface of the frame is
An entrance device for a shield machine in a shaft, wherein the entrance device is configured to be located behind a disk . 2. A cylindrical frame provided with a sealing member of a shield machine on an inner surface inside a retaining wall of a shaft, and the shield machine is cut by the shield machine inserted into the cylindrical frame to form a shield machine. In the starting method for starting, the cylindrical frame is composed of an outer frame and an inner frame, a seal member is provided between the outer frame and the inner frame, and a seal member of a shield machine is provided on an inner surface of the inner frame. Is fixed inside the earth retaining wall of the shaft, the inner frame is housed in the outer frame, the shield machine is assembled in this housed state and set in the inner frame, and then the inner frame is extended to the rear of the shield machine. In a shaft, characterized in that the shield machine is started in this extended state. Starting method of Rudo machine.