JP3171459B2 - Shield method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shielding method.

[0002]

2. Description of the Related Art In a shield method, when a tunnel is dug to a certain extent by a shield machine, the cutter mechanism of the shield machine becomes significantly worn. Recently, it has become possible to perform excavation of about 1 to 2 km before the material and performance of the shield machine are improved and wear of the cutter mechanism becomes significant. However, conventionally, when the wear of the cutter mechanism of the shield machine becomes remarkable, it is considered that the life of the shield machine has ended at this point.

[0003]

In the above-mentioned conventional method, when the wear of the cutter mechanism and the front plate becomes remarkable, the life of the shield machine ends, and a new shield machine is used. It also takes time to replace. It is considered to reinforce the ground in front of the shield machine by injecting a chemical solution and then excavate to form a space, and to update the cutter mechanism and front plate using this space,
This method requires a lot of work for excavation and has a problem in safety.

[0004]

According to the present invention, as a means for solving the above-mentioned conventional problems, a cutter mechanism is mounted on the front surface of an inner body (2) which is slidably fitted to an outer body (3). The tunnel (15) is dug using the shield machine (1) equipped with (7), and when the cutter mechanism (7) is worn, the excavation is interrupted and the outer shell is cut off.
With respect to (3), the inner trunk (2) is retracted, and at the trace, water-impervious and reinforced walls (20A, 21A) are formed in the water-impervious and reinforcing zones (20, 21). Retract the vulnerable zone (22)
The fragile layer (22A) is formed at the point, and when the reinforcing wall (20A, 21A) reaches the predetermined strength, the fragile layer (22A) is removed. It is intended to provide a shield method for restarting the shield machine (1) after updating (7).

[0005]

According to the present invention, the water shielding and reinforcing zones (20, 21) are retracted by retracting the inner body (2) into the cave (15) dug by the cutter mechanism (7) of the inner body (2). In step (2), a water impervious and reinforcing wall (20A, 21A) is formed, and then a weak layer (22A) is formed in the weak zone (22). The vulnerable layer (22A) is very easy to excavate, but the front face is impermeable and reinforced
0A, 21A) and the surrounding area is protected by the outer shell (3), so the fragile zone (22)
Is removed and there is no danger of the collapsed space (23) from collapse from the surrounding ground (14). Then, the cutter mechanism (7) is updated using the space (23) as a working space.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to one embodiment shown in FIGS. 1 to 6. A shield machine (1) comprises an inner body (2) and an inner body (2).
And an outer body (3) fitted slidably back and forth,
On the front surface (4) of the inner body (2) is provided a cutter mechanism (7) comprising a spoke (5) having a number of bits (5A) and a fish tail (6).

A discharge port (8) is provided on the front surface (4) of the inner body (2).
A screw conveyor (10) is arranged on the back of the outlet (8). The cutter mechanism (7) is driven by a motor (11), and an inlet (12) communicates with the center of the cutter mechanism (7).

The inner shell (2) and the outer shell of the shield machine (1)
(3) is detachably fixed by a plurality of fixing bolts (13) as shown in FIG. And inner torso (2) and outer torso
The width W of the gap in (3) is usually 7 to 15 mm, and the inside is filled with grease.

The shield machine (1) is advanced, and the cutter mechanism (7) is driven to dig a tunnel (15) into the ground (14) as shown in FIG. The periphery of the tunnel (15) is reinforced successively with steel or concrete segments (16). A jack (17) is installed between the segment (16) and the inner body (2) of the shield machine (1),
The hydraulic pressure applied to the jack (17) becomes the driving force of the shield machine (1). A tail packing (18) is interposed between the outer shell (3) of the shield machine (1) and the segment (16).
The soil or mud generated by moating is discharged by a screw conveyor (10) through a discharge port (8).

In the above shield method, a cutter mechanism is provided.
When the bit (5A) of the spoke (5) mainly in (7) is significantly worn, the drilling by the shield machine (1) is stopped and the inner body (2)
Remove the fixing bolts (13) connecting and fixing the outer shell (3) and the inner shell to the anchor (19) of the outer shell (3) as shown in FIG.
The jack (17) of (2) is connected, and the inner trunk (2) is retracted from the state of FIG. 1 to the state of FIG.

When the inner body (2) is retracted, as shown in FIG.
To form the impermeable wall (20A), then discharge the reinforcing material in the reinforcing zone (21) to form the reinforcing wall (21A), and discharge the brittle material in the brittle zone (22). A fragile layer (22A) is formed. The discharge pressure of the material is used as a retraction propulsion force of the inner body (2) together with the traction force of the jack (17).

The water-stopping material is, for example, a mixed slurry of soil and a soil hardening agent. The reinforcing material is, for example, foamed mortar, poorly-mixed mortar, cement-waterglass compound, and the fragile material is, for example, Non-hardening clay, sludge such as bentonite. Usually, the strength of the reinforcing wall (21A) is about 80 to 150 kg / cm ² and the thickness is about 1.5 m. In the fragile zone (22), the cutter mechanism (7) is driven to inject the fragile material.
Through a screw conveyor (10). If strength is developed in the formed fragile layer (22A), a tensile force acts when the inner body (2) is retracted, so that no strength is developed as described above.

In this manner, the impermeable wall (2) is provided in the impermeable zone (20).
0A), a reinforcing wall (21A) is formed in the reinforcing zone (21), and a fragile layer (22A) is formed in the fragile zone (22). Shield machine (1)
The manhole (9) is opened to remove the soil forming the vulnerable layer (22A) from the top, and the space (2)
After reinforcing the front surface of 3) with a retaining plate (24), the space
Using (23) as a work space, update the cutter mechanism (7). The front of the space (23) is provided with water impervious and reinforced walls (20A, 2
1A) and the surroundings are protected by the outer shell (3), so that the work can be performed extremely safely.

After the cutter mechanism (7) is updated as described above, the shield machine (1) is restarted. In this case, as shown in FIG. Attach the tail body (26) having the packing (25), and place the tail packing between the newly installed segment (16A) and the tail body (26).
(25) is interposed. The thrust of the shield machine (1) is obtained by hydraulically pushing the segment (16A) by the jack (17) of the inner body (2). In this case, outer trunk (3)
Go to that place. Segment (16A) is the inner body
The diameter is smaller due to the difference in diameter between (2) and outer shell (3).

In addition to the above embodiment, for example, the impermeable wall and the reinforcing wall may be integrated into one wall. Also, the outer trunk may be rejoined without being discarded at the time of restart. The present invention is also applicable to a face plate type shield machine.

[0016]

Therefore, in the present invention, when the cutter mechanism of the shield machine is worn out, the cutter mechanism can be easily renewed, and the length of the cave excavated by one shield machine is large. Increase in width.

[0017]

[Brief description of the drawings]

 1 to 6 show one embodiment of the present invention.

FIG. 1 is an explanatory diagram when a shield machine is stopped.

FIG. 2 is an explanatory view of a connection state between an inner trunk and an outer trunk.

FIG. 3 is an explanatory view of a jack when the inner trunk is retracted.

FIG. 4 is an explanatory view when the retreat of the shield machine is completed.

FIG. 5 is an explanatory diagram when the cutter mechanism is updated.

FIG. 6 is an explanatory diagram when the shield machine is restarted.

[Explanation of symbols]

 1 Shield machine 2 Inner body 3 Outer body 4 Front 7 Cutter mechanism 20 Water barrier zone 20A Water barrier 21 Reinforcement zone 21A Reinforcement wall 22 Vulnerable zone 22A Vulnerable layer

Claims (1)

(57) [Claims] 1. A cave is excavated by using a shield machine having a cutter mechanism on a front surface of an inner trunk fitted slidably back and forth on an outer trunk. Stop moving and retreat the inner torso relative to the outer torso. In that area, form a water impervious and reinforcing wall in the water impermeable and reinforcing zone, and then retreat the inner torso to form a vulnerable layer in the vulnerable zone. And
Shielding method characterized by removing the fragile layer when the reinforcing wall reaches a predetermined strength, renewing the cutter mechanism using the space inside the outer shell at the trace, and restarting the shield machine.