JP3068396B2 - Shield excavator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield excavator,
In particular, the present invention relates to a sealing device for shortening the time required for connecting a shaft and a shield excavator.

[0002]

2. Description of the Related Art A conventional connection method will be described with reference to FIGS. In FIG. 8, reference numeral 1 denotes a concrete shaft based on a caisson foundation, which is buried in a ground 2. A portion 5 of the side wall 3 of the shaft 1 which is removed for connection with the shield excavator 4 includes an inner portion 5A made of concrete having high strength and an outer portion 5 made of mortar having low strength.
B The inner part 5A is a shield excavator 4
Is made thin as long as necessary strength can be secured before connection, and is hereinafter referred to as a temporary wall. The side wall 3 of the shaft 1 penetrates a ground improvement agent injection passage 6 that opens to the ground 2 side, and is connected to a mortar tank (not shown) via a valve 7.

When the shield excavator 4 digs through the tunnel and reaches the shaft 1 as shown in FIG. 8, it excavates the mortar portion 5B as it is, and stops excavation just before the temporary wall 5A as shown in FIG. In this state, the mortar 8 is injected into the ground 2 from the shaft 1 side through the injection passage 6 and further from the shield excavator 4 side, and the shield body (skin plate) 9
And the ground around the segment 10 behind it. This ground improvement is performed when removing the temporary wall 5A.
This is to prevent earth and sand and water from flowing into the shaft 1 from 1.

After the mortar is injected and the ground improvement is completed, the temporary wall 5A is removed from the shaft 1 by another machine 12 as shown in FIG. As a result, shaft 1
Since the shield excavator 4 penetrates and connects both,
The shield body 9 is left as a tunnel structure, and other devices such as the cutter head 13 are carried away, and an appropriate post-processing is performed. After the removal of the temporary wall 5A, the shield excavator 4 may be advanced until the hood 14 at the tip of the shield body 9 enters the shaft 1 as shown in FIG.

[0005]

As a method for preventing a large amount of sediment and water from flowing in when removing the temporary wall 5A, as described above, conventionally, the mortar 8 is simply injected into the ground 2 to improve the ground. is there. Therefore, the shield body 9 and the segment 10
Until the mortar 8 is injected over a wide area around the ground and the ground is sufficiently hardened, the work of removing the temporary wall 5A and the work of moving the shield main body 9 cannot be performed, and the construction period is long. In the case of large tunnels, mortar injection takes more than one month.

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, an object of the present invention is to provide a shield excavator provided with a sealing device capable of shortening a period required for connecting a shaft and a shield excavator.

[0007]

A shield excavator according to the present invention is provided at a front end of a shield body of a shield excavator.
A hood, an annular recess formed and fixed on the outer periphery of the front part of the shield body, and the shield body attached to the annular recess,
And the hole drilled by the shield excavator into the shaft.
A hollow seal ring having a resilient to Le, the protective cover of the outer periphery in the longitudinal direction movable annular front Symbol annular recess the shield body has covering openably openings, said annular recess
Move the protective cover into the hole while entering the hole.
A drive device for driving the opening and closing of the unit, and connected to the hollow seal
When the opening is open, pressurized fluid is applied to the hollow seal.
And a pressure fluid source for supplying and expanding the diameter .

[0008]

[Action] Before the temporary wall (inside part) of the shaft connection part is removed from the inside of the shaft, the valve is opened with the hollow seal formed in the hole formed by excavating the outside part, and the pressure fluid is passed through the hollow seal. Put in. As a result, the hollow seal expands in diameter and protrudes outward from the shield main body, thereby sealing between the hollow seal and the shaft. that time,
Normally, the protective cover is moved by the driving device to make the annular recess
Close and protect the hollow seal and supply pressure fluid
When expanding the hollow seal, the protective cover is
Move to open the annular recess to allow sealing. Therefore, even if the work of removing the temporary wall is performed in parallel with the injection of the ground improvement agent, it is possible to prevent earth and sand and water from flowing into the shaft, thereby shortening the construction period. Also, the protective cover and its drive
Since the annular recess is opened and closed by the device, it is always a hollow seal
Good protection and can be stored in the annular recess
You.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 4 shows the overall schematic configuration. As shown in FIG. 4, the front end of the shield body 9 of the shield excavator 4 is
Is installed, but instead of this hood 14,
An annular sealing device 1 is provided on the outer periphery of the front part of the shield body 9 itself.
Yes 5 is provided, of the side wall 3 of the vertical shaft 1, and the inner portion or temporary wall 5A also made of concrete with conventional connecting portion 5 of the shield excavator 4, the mortar made or sponge or rubber outer portion 5B In this case, the thickness of the temporary wall 5A is set to about 1/4 of the thickness of the side wall 3.

The details of the sealing device 15 will be described with reference to FIGS. The sealing device 15 includes an annular hollow seal (tube) 17 made of rubber or synthetic resin, and a pressure fluid source 18 connected to the hollow seal 17 via a valve 21. And not the hood installed at the front end of the shield body ,
An annular recess 19 is formed by fixing the position on the outer periphery of the front part of the shield body 9 itself, and the hollow seal 17 is annularly installed along the annular support member 20 at the bottom. The hollow seal 17 has a constricted portion 17a, and is fixed to the support member 20 along a reinforcing iron plate 22 along the inner peripheral side. Also,
To increase the protection and certainty of the housing of the hollow seal 17, the opening of the annular recess 19 movable annular cover 23 in the longitudinal direction of the shield body 9, the cover 23 so as to open and close driven by a jack 24 It is. Cover 23 at all times
Is closed in the forward position, and when the diameter of the hollow seal 17 is expanded, the cover 23 is retracted to supply the pressurized fluid. In the figure, 18A is a flow path of the pressure fluid, 2
Reference numeral 5 denotes a support member such as a cutter head driving mechanism, and 26 denotes a mortar injection passage on the shield excavator side.

With the above configuration, the hollow seal 17 does not normally enter the annular concave portion 19 and does not protrude, but opens the valve 21 to supply the pressure fluid to the inside, thereby performing the sealing operation by expanding the diameter.

Next, a method of connecting a shield excavator and a shaft according to the present invention will be described with reference to FIGS.

As a connection work, when the shield excavator 4 reaches the shaft 1, the valve 7 on the shaft 1 and the valve 16 on the shield excavator 4 are opened as shown in FIG. And the injection of the mortar 8 is started.

Next, during injection of the mortar, as shown in FIG. 5, the shield excavator 4 is advanced, and excavation of the connection portion 5 of the shaft 1 is started. During the excavation, after the annular sealing device 15 enters the excavated hole 5C, the annular sealing device 15 is protruded outward from the shield body 9 to seal the space between the shaft 1 and the shaft 1. For example, as shown in FIG. 5, just after the excavation of the outer portion 5B is completed , the cover 23 is opened with the jack 24, and then the pressurized fluid is supplied into the hollow seal 17 to activate the sealing device 15, and in this state, The advance of the shield excavator 4 is stopped.

Then, while the mortar is being injected and the sealing by the sealing device 15 is performed, as shown in FIG. 6, the concrete temporary wall 5A of the connecting portion 5 is removed from the shaft 1 by the machine 12.

After the removal of the temporary wall 5A, the shield excavator 4 is advanced and stopped as necessary until the hood 14 of the shield body 9 just enters the shaft 1 as shown in FIG.

After the temporary wall 5A is removed or after the shield excavator 4 advances, the injection of the mortar 8 is continued and stopped when the required amount is reached. During this time, appropriate post-processing such as removal of the cutter head 13 and the like and secondary winding work inside the shield body 9 are performed. Even if the annular sealing device 15 is left as it is,
Or you may remove it.

[0019]

Since the shield excavator of the present invention has an annular hollow seal protruding by the pressurized fluid on the outer periphery of the front part of the shield body, the connection between the shield body and the shaft during injection of the ground conditioner is improved. The work of removing the inner part (temporary wall) of the connection part by sealing between the inner circumferences can be performed in parallel,
The connection period between the shaft and the shield excavator can be shortened. Therefore, it is necessary to remove the temporary wall during the injection of the ground conditioner.
Prevent sediment and water from flowing into the shaft even when going in parallel
It is possible to shorten the construction period. In addition, the system of the present invention
The excavator has an annular recess in which an annular hollow seal is mounted.
An annular protective cover that can be moved back and forth so that it can be opened and closed
A bar is provided, and this protective cover is moved
So that the annular recess is always closed with a protective cover and
The empty seal can be well protected and accommodated.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing one embodiment of the present invention.

FIG. 3 is a sectional view showing one embodiment of the present invention.

FIG. 4 is a diagram showing a method of connecting a shaft with a shaft by the shield excavator of the present invention.

FIG. 5 is a view showing a method of connecting a shaft with a shaft by the shield excavator of the present invention.

FIG. 6 is a diagram showing a method of connecting a shaft with a shaft by the shield excavator of the present invention.

FIG. 7 is a diagram showing a method of connecting a shaft with a shaft by the shield excavator of the present invention.

FIG. 8 is a diagram showing a conventional technique.

FIG. 9 is a diagram showing a conventional technique.

FIG. 10 is a diagram showing a conventional technique.

FIG. 11 is a diagram showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vertical shaft 2 Ground 3 Side wall 4 Shield excavator 5 Connection part 5A Inner part (temporary wall) 5B Outer part 5C Hole 6,26 Injection passage 7,16,21 Valve 8 Ground improvement agent (mortar) 9 Shield body 10 Segment 13 Cutter head 14 hood 15 sealing device 17 annular hollow seal 18 pressure fluid source 19 annular recess

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-231600 (JP, A) JP-B-5-24319 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21D 9/06 301

Claims (1)

(57) [Claims] At the front end of a shield body of a shield excavator
A hood to be provided and a solid formed on the outer periphery of the front part of the shield body.
An annular recess to be set, and the seal attached to the annular recess.
Between the main body and the hole that the shield excavator excavates in the shaft.
A hollow seal ring having a resilient sealing the an annular protective cover possible longitudinal movement on the outer periphery of the front Symbol annular recess the shield body has covering openably the opening of the annular
Move the protective cover with the concave part
A drive device for opening and closing the opening, and the hollow seal
Pressure is applied to the hollow seal when the opening is open
And a pressure fluid source for supplying a fluid and expanding its diameter .