JP3172432B2 - Starting a shield machine from a shaft - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for starting a shield machine for excavating a tunnel from an established mine.

[0002]

2. Description of the Related Art When a tunnel is excavated underground with a shield machine, a start shaft and an arrival shaft of the shield machine are constructed, and then the shield machine is excavated from the start shaft toward the arrival shaft. Conventionally, when starting a shield machine from the starting shaft, the starting wellhead of the shield machine is formed on the retaining wall of the starting shaft, a shield machine is installed in the shaft to this wellhead, and in the case of soft ground with a lot of groundwater, the wellhead After improving the ground in front by injecting a chemical, the wellhead wall was destroyed and the shield machine was started.

[0003]

However, according to the above-described method for starting a shield machine, since the entire shield machine must be installed in the shaft toward the start wellhead, it takes time to assemble the shield machine. Not only
In order to install the entire shield machine in the mine, a large shaft had to be built. Furthermore, when the ground is soft, after the construction of the shaft, it is necessary to perform a chemical injection treatment to prevent infiltration of groundwater when the shield machine starts, and there is a problem that the construction period becomes long.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to enable the shield machine to be started even though the shaft for starting the shield machine is small in diameter, and to inject a chemical solution. An object of the present invention is to provide a method of starting a shield machine from a shaft, which can eliminate the need for an auxiliary construction method, efficiently perform assembling work of the shield machine, and shorten the construction period.

[0005]

In order to achieve the above-mentioned object, a method for starting a shield machine from a shaft according to the present invention is provided. While excavating a vertical hole along the outer surface of the wall, a hood portion of a skin plate in a sheath tube having a front end opening closed by a ground collapse prevention wall, and a cutter plate disposed at an open end in the hood portion; The front half of the shield machine comprising the partition wall supporting the rotating shaft of the cutter plate is housed, and the sheath tube containing the front half of the shield machine is hung down to a predetermined depth in the vertical hole to open the rear end of the sheath tube. After the part is brought into water-tight contact with the outer surface of the earth retaining wall of the established mine, the earth retaining wall portion on the rear side of the sheath pipe is cut off from the established mine to form a communication hole communicating with the sheath pipe. Stored in After assembling the shield machine by connecting the shield machine half portion on the rear end of the shield machine first half, and is characterized in that to start the shield machine.

In the method for starting a shield machine, as described in claim 2, a water stop ring is attached to the inner peripheral surface of the sheath tube, and the water stop ring is closely attached to the outer peripheral surface of the hood portion in the front half of the shield machine. It is desirable that the hood portion in the front half of the shield machine be temporarily fixed to the sheath tube with a pin that can be pulled out.

In the case where a vertical hole is excavated on the outer surface of the retaining wall of the shaft, the vertical hole is excavated while filling the stabilizing liquid as described in claim 3, and the sheath tube containing the front half of the shield machine is vertically excavated. 6. The stable liquid may be gelled after being suspended to a predetermined position in the hole and brought into close contact with the outer surface of the retaining wall.
As described in the above, after the sheath tube containing the first half of the shield machine is hung down to a predetermined position in the vertical hole and brought into close contact with the outer surface of the retaining wall, the inside of the vertical hole may be backfilled with earth and sand. As means for bringing the sheath tube into close contact with the outer surface of the retaining wall of the shaft,
As described in the above, the suction packing is attached to the rear end opening edge of the sheath pipe, and the suction packing is brought into close contact with the outer surface of the retaining wall of the shaft, and then the stable liquid in the sheath pipe is suctioned out to remove the suction packing. Can be adsorbed on the outer surface of the earth retaining wall of the shaft, and when the vertical hole is excavated, the rear end opening edge of the sheath pipe can be fixed to the outer surface of the earth retaining wall by using an appropriate fixing bracket and a sealing material. It is sufficient to make it adhere to.

[0008]

[Function] When constructing a starting shaft for a shield machine, the shaft should be large and shaped so that the rear half of the shield machine can be stored. After the construction of this shaft, a vertical hole into which the front half of the shield machine can be inserted is excavated along the outer surface of the retaining wall of the shaft on which the shield machine is started. At this time, the vertical hole is excavated while the stable hole is filled with a stable liquid such as muddy water. On the other hand, the first half of the shield machine is previously integrated into a sheath pipe, and this sheath pipe is suspended from the ground into a vertical hole, and its rear end opening is brought into close contact with the outer surface of the retaining wall of the shaft. In this state, when the stable liquid in the sheath tube is suctioned and eliminated from the ground side, the inside of the sheath tube becomes negative pressure, and the suction packing attached to the rear end opening edge of the sheath tube is adsorbed on the outer surface of the retaining wall and the sheath tube is sucked. Is fixed. In this state, the stabilizing solution is gelled, or earth and sand is charged into the vertical hole to bury the sheath tube in the vertical hole.

Next, a portion of the retaining wall on the rear side of the sheath pipe is cut off from the inside of the shaft to form a communication hole communicating with the rear end opening of the sheath pipe. At this time, by installing a water-stop packing in close contact with the outer peripheral surface of the hood in the front half of the shield machine on the inner peripheral surface of the sheath tube, the ground collapse prevention wall stretched over the front end opening of the sheath tube. Even if the material has water permeability, the watertight packing and the partition wall stretched in the hood prevent the groundwater from entering the shaft. In addition, by filling a pressure liquid such as water or muddy water in advance in a space surrounded by the back surface of the ground collapse prevention wall and the water stop packing and the partition wall, the filling pressure is applied as a back pressure to the face collapse prevention wall. By acting, earth pressure can be reliably received. In other words, the partition wall of the shield machine exhibits the soil retaining function, so that even in the case of soft ground, there is no need for an auxiliary construction method such as a chemical injection treatment.

After the above-mentioned communication hole leading to the sheath pipe is formed in the earth retaining wall portion of the shaft, a shield machine is assembled in the shaft.
At this time, since the first half of the shield machine is disposed outside the shaft as described above, the latter half of the shield machine may be housed inside the shaft, so that the shaft can be downsized and the shield machine can be installed. Assembly work can be performed efficiently.

In the case where the ground is made of stable soil, the sheath pipe containing the front half of the shield machine is dug out by digging the vertical hole without using a gelling stabilizing solution, and the outer surface of the earth retaining wall of the shaft is used. After fixing using appropriate metal fittings etc., it may be backfilled with earth and sand, and after drilling a vertical hole in muddy water and adsorbing the sheath tube to the outer surface of the retaining wall as described above, Earth and sand may be charged to replace the mud.

The shield machine is assembled by bringing the latter half of the shield machine into the shaft and connecting it to the rear end of the former half of the shield machine through a communication hole, and then rotating the cutter plate of the shield machine into the sheath tube. When the shield machine is started through, the face collapse prevention wall stretched at the front end opening of the sheath tube is crushed by the cutter plate, taken in on the back side of the cutter plate, connected to the partition and connected with the sediment discharge means. Through the air. Subsequently, the shield machine will be propelled and the tunnel will be dug underground.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, specific embodiments of the present invention will be described with reference to the drawings. First, as shown in FIG. 1, in an established pit 1, a shield machine front half 3 housed in a sheath pipe 2 along an outer surface of a retaining wall on a side where a shield machine S is started.
The vertical hole 5 into which can be inserted is excavated. The established shaft 1 may be formed by a caisson.
Is formed of a continuous underground wall, and the size and shape of the inside are formed so that the shield machine rear part 4 described later can be stored therein.

The sheath tube 2 is formed of a short tube-shaped steel tube, and a ground collapse prevention wall 6 made of a material that can be cut and crushed by a cutter plate of the shield machine S, for example, a fiber-mixed concrete, is stretched over the front end opening. The opening is completely closed by the ground collapsing prevention wall 6, and the tongue-shaped cross-section of water is inclined obliquely inward toward the front on the inner circumferential surface of the intermediate portion in the longitudinal direction. The packing 7 is mounted over the entire circumference. Further, on the opening edge of the rear end of the sheath tube 2, a suction packing 8 having a tongue-shaped cross section inclined rearward toward the front end is attached over the entire circumference, and pins are attached to a plurality of portions of the tube wall at the rear end. The through hole 2a is provided. In addition, a suction tube 9 communicating with the inside of the sheath tube 2 is connected to and communicated with an appropriate position at the rear end of the sheath tube 2.

The first half 3 of the shield machine housed in the sheath tube 2
Is a hood portion 31 of a skin plate made of a short tubular steel pipe having a diameter smaller than that of the sheath tube 2, a cutter plate 32 disposed at a front end opening of the hood portion 31, and a hood portion 31 behind the cutter plate 32. A partition wall 33 that integrally fixes its outer peripheral edge to the inner peripheral surface to partition the hood portion 31 forward and backward, and a rotating shaft 34 of the cutter plate 32 rotatably supported by the partition wall 33. The lower end of the partition wall 33 is provided with an opening 35 for connecting an opening end of the screw conveyor 10 which is earth and sand discharging means described later, and the opening 35 is airtightly closed by the lid 11. ing. Further, the outer half surface of the hood portion 31 of the shield machine front half 3 is brought into water-tight contact with the water-stop packing 7 mounted on the inner circumferential surface of the sheath tube 2 and a plurality of rear end portions of the hood portion 31 are provided. In addition, a pin insertion hole 36 is provided to correspond to the pin locking hole 2a provided in the sheath tube 2, and the pin 12 is inserted into the pin locking hole 2a from the pin insertion hole 36 and locked, and the sheath tube 2 The front half 3 of the shield machine is disposed therein while maintaining a predetermined posture.

The excavation of the vertical hole 5 is carried out by using the excavating equipment used for constructing the shaft 1 composed of the continuous underground wall, and the stable liquid 13 composed of muddy water is filled in the vertical hole 5 to prevent the ground from collapsing. It is excavated to a predetermined depth. After excavation of this vertical hole 5, the cutter plate 32 of the front half 3 of the shield machine is turned in the tunnel excavation direction, and the sheath tube 2 incorporating the front half 3 of the shield machine is turned.
Is suspended in the vertical hole 5 by a crane or the like to a position where the shield machine starts at the lower end of the outer surface of the retaining wall of the shaft 1. At this time, the ground collapse prevention wall 6 is suspended in advance or while being suspended.
Of the back of the machine, watertight packing 7 and bulkhead of the first half 3 of the shield machine
A pressure liquid such as water or muddy water is injected into the front space portion 14 between the front surface of the fuel cell 33 and the front surface of the fuel cell 33 so as to be full.

When the sheath tube 2 is suspended, the stabilizing liquid 13 fills the water-stop packing 7 and the rear space 15 of the partition wall 33 of the front half part 3 of the shield machine, and stretches the front end opening of the sheath tube 2. The pressure from the ground side acts on the ground collapse prevention wall 6, which is balanced with the pressure on the ground side by the pressure liquid filled in the front space portion 14. In addition, the ground collapse prevention wall 6 may have water permeability.

Next, as shown in FIG. 2, on the outer surface of the retaining wall of the shaft 1, the suction packing 8 attached to the rear end of the sheath tube 2 is used.
Suction tube 9 extending to the ground with
When the stable liquid 13 filled in the rear end space 15 of the sheath tube 2 is suctioned and removed by a vacuum pump (not shown) through
The pressure in the rear end space 15 is reduced and the suction packing 8 is
The sheath tube 2 containing the front half portion 3 of the shield machine is fixed to the outer surface of the retaining wall. At this time, the watertight packing 7 is more firmly pressed against the outer peripheral surface of the hood portion 31 by the negative pressure, and the inside of the hood portion 31 is separated from the cutter plate 32 side by the partition wall 33. There is no danger that the pressurized liquid leaks from the side space 14 to the rear space 15.

In this state, earth and sand are put into the vertical hole 5 from the ground and replaced with the stabilizing liquid 13 to bury the sheath tube 2 containing the front half 3 of the shield machine, or
As described above, the sheath tube 2 is adsorbed on the outer surface of the earth retaining wall of the shaft 1 using a sol-like material obtained by mixing cement with a stable liquid obtained by mixing bentonite, and then gelled (solidified) to form the sheath tube 2. Bury and fix.

Thereafter, as shown in FIG. 4, the retaining wall portion on the rear side of the sheath pipe is cut off from the inside of the shaft 1 using an appropriate crushing device, and a communication hole 16 communicating with the rear end opening of the sheath pipe 2 is formed. After drilling. As shown in FIG. 5, the shield body middle part and the rear body part are sequentially assembled at the rear end of the shield machine front half part 3 through the communication hole 16 to form the shield machine rear half part 4. That is, the skin plate is attached to the rear end of the hood 31 in the first half 3 of the shield machine.
41 and the bulkhead 33 in the first half of the shield machine.
A driving device 42 for the cutter plate 32 is mounted on the rear side of the screw conveyor 10. Further, after the lid 11 is removed from the opening 35 provided at the lower end of the partition wall 33,
The propulsion jacks 43 are provided at a plurality of locations on the inner peripheral surface of the skin plate 41, and the erection device 44 is provided in the rear portion to assemble the shield machine S.

At the same time as the assembling operation of the shield machine S, a wellhead ring 17 and a wellhead packing 18 slidably contacting the outer peripheral surface of the skin plate 41 are mounted on the inner surface of the retaining wall 1 so as to surround the rear end opening of the sheath tube 2. At the same time, the bearing wall 19 is fixed to the inner surface of the retaining wall 1 facing the rear end of the shield machine S.

Next, the hood portion 31 of the front half portion 3 of the shield machine fixed to the sheath tube 2 fixed to the outer surface of the retaining wall of the shaft 1 is made movable by extracting the pin 12 and then the cutter plate of the shield machine S is removed. Supporting wall 19 while rotating 32
When the shield machine S is propelled by taking the reaction force to extend the propulsion jack 43, the face collapse prevention wall 6 stretched at the front end opening of the sheath tube 2 is crushed by the cutter plate 32, and the cutter plate 32 is crushed. The pressure liquid filled in the front space portion 14 of the partition wall 33 of the front half part 3 of the shield machine taken into the rear side of the shield machine 32 is discharged backward by the screw conveyor 10 together with the pressurized liquid and carried out of the shaft into the ground.

Subsequently, when the shield machine S is propelled,
As shown in FIG. 6, the ground on the front side is excavated from the face collapse prevention wall 6 to form a tunnel toward a reaching shaft (not shown). Then, the segments 20 are assembled in the rear end of the skin plate 41 in accordance with the excavation of the tunnel, and the excavation wall surface is lining. Although the mechanical shield excavator is shown as the shield machine S in the above embodiment, a muddy shield excavator may be used.

[0024]

As described above, according to the present invention, when the shield machine is started from the inside of the shaft, a vertical hole is excavated in advance on the outer surface of the shaft, and the sheath tube containing the front half of the shield machine is removed. The sheath tube is suspended in the vertical hole and buried in the vertical hole in a state where the sheath tube is in close contact with the outer surface of the shaft of the shield machine launch site, and thereafter, a communication hole is provided from the shaft to the rear end of the sheath tube. Since the shield machine is assembled by connecting the rear end of the shield machine inside the shaft and connecting the rear end of the shield machine to the front half of the shaft, it is only necessary to have enough space in the shaft to accommodate the rear end of the shield machine. Therefore, the shaft can be reduced in size, the shaft can be efficiently constructed, the assembling work of the shield machine can be performed smoothly, and the construction period can be shortened.

Further, since the face collapse prevention wall is provided at the front end opening of the sheath pipe, the ground can be pressed down by the face collapse prevention wall to prevent the collapse, and the shield machine is provided on the inner peripheral surface of the sheath pipe. By providing a water-tight packing in close contact with the outer peripheral surface of the hood in the first half, even if the face collapse prevention wall is permeable, groundwater is prevented from entering the shaft through the gap between the sheath tube and the hood. In addition, since the space in front of the hood and the inside of the vertical shaft in the back of the hood are cut off by a partition wall stretched over the hood in the first half of the shield machine, pressure space such as pressure water By filling the pressurized liquid, a back pressure opposite to the ground pressure can be applied to the face collapse prevention wall, and even with soft ground, there is no need for an auxiliary construction method such as chemical injection processing, reducing cost. What you get That.

[Brief description of the drawings]

FIG. 1 is a simplified longitudinal side view of a state where the first half of a shield machine is inserted into a vertical hole.

FIG. 2 is a simplified vertical sectional side view showing a state in which a first half of a shield machine is buried in a vertical hole.

FIG. 3 is a cross-sectional view thereof.

FIG. 4 is a simplified longitudinal side view showing a state in which a communication hole is provided from the inside of the shaft to the front half of the shield machine,

FIG. 5 is a simplified vertical sectional side view of a state where the shield machine is assembled.

FIG. 6 is a simplified vertical side view of the state in which the shield machine has started.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vertical shaft 2 Sheath tube 3 First half of shield machine 31 Hood part 32 Cutter plate 33 Partition wall 34 Axis of rotation 4 Shield second half 5 Vertical hole 6 Ground collapse prevention wall 7 Waterproof packing 8 Adsorption packing 12 pin

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) E21D 9/06 301

Claims (5)

(57) [Claims] When a shield machine is started from an established mine, a vertical hole is excavated along an outer surface of a retaining wall of the established mine on which the shield machine is started, and a front end opening is closed by a ground collapse prevention wall. The front half of a shield machine comprising a hood portion of a skin plate, a cutter plate disposed at an open end in the hood portion, and a partition wall supporting a rotating shaft of the cutter plate is housed in a sheath tube formed by the above-mentioned sheath tube. After the sheath tube containing the front half of the machine is hung down to a predetermined depth in the vertical hole, the rear end opening of the sheath tube is brought into close contact with the outer surface of the earth retaining wall of the established mine, and then the sheath tube is taken out of the established mine. A rear part of the retaining wall is cut off to form a communication hole communicating with the sheath tube, and the rear end of the shield machine is connected to the rear end of the first half of the shield machine housed in the sheath tube through the communication hole. After assembling the A method for starting a shield machine from a shaft, comprising starting a shield machine. 2. A water-stop ring is attached to the inner peripheral surface of the sheath tube so that the water-stop ring is in close contact with the outer peripheral surface of the hood portion of the front half of the shield machine, and the hood portion of the front half of the shield machine is pulled out into the sheath tube. 2. The method for starting a shield machine from a shaft according to claim 1, wherein the shield machine is temporarily fixed with a possible pin. 3. The vertical hole is excavated while being filled with a stabilizing liquid, and a sheath tube containing the first half of the shield machine is hung down to a predetermined position in the vertical hole to adhere tightly to the outer surface of the earth retaining wall. The method for starting a shield machine from a shaft according to claim 1, wherein the shield machine is gelled. 4. An adsorption packing is attached to the rear end opening edge of the sheath pipe, and the adsorption packing is brought into close contact with the outer surface of the earth retaining wall of the pit, and then the stable liquid in the sheath pipe is sucked to set the adsorption packing. The method for starting a shield machine from a shaft according to claim 1, wherein the shield machine is caused to be adsorbed to an outer surface of the earth retaining wall. 5. The method according to claim 1, wherein the sheath tube containing the front half of the shield machine is hung down to a predetermined position in the vertical hole, brought into close contact with the outer surface of the retaining wall, and then filled in with the earth and sand. 1. A method for starting a shield machine from a shaft according to item 1.