JPH06200699A - Sealing device in shielding machine - Google Patents

Abstract

(57) [Summary] [Purpose] The impermeable membrane for coating concrete that will be cast in situ in an excavated tunnel is pulled out from the inside of the shield machine while preventing damage, and the placed concrete is prevented from entering the inside of the machine. [Structure] A pair of elastic seal materials 1 inside and outside is provided at an impermeable membrane outlet 8 of an impermeable membrane storage chamber 6 provided in the shield machine main body 1.
1 and 12 are attached to the elastic sealing members 11 and 12 so that the impermeable membrane 5 can be pulled out in a sandwiched state without slidingly contacting the inner wall of the outlet 8 and one elastic sealing member 12 can be expanded in the radial direction. The sealing pressure is increased to prevent the concrete 34 from wrapping around from the outer peripheral surface of the rear body 4 to the inside of the machine when the concrete 34 is placed on the formwork 7 assembled in the rear body 4 of the shield machine body 1. It is configured to do.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield machine in which a tunnel under excavation is provided with a cast-in-place concrete lining and the concrete lining is covered with an impermeable membrane. The present invention relates to a sealing device that prevents the occurrence of dripping.

[0002]

2. Description of the Related Art Conventionally, in order to apply a cast-in-place concrete lining to a tunnel excavated by a shield machine, a mold is assembled on the inner peripheral surface of the tunnel extending from the rear part of the shield machine to a rear part as appropriate, This is done by filling concrete between the frame and the wall surface of the tunnel excavation.

In this case, the concrete comes into direct contact with the excavated ground and a part of the concrete penetrates into the excavated ground, which requires an extra filling amount of concrete, which is uneconomical, and also mixes groundwater, earth and sand, etc. There is a risk that the concrete will deteriorate in quality and the concrete lining of a predetermined strength may not be obtained, and further, after solidification of the concrete, groundwater permeates into the concrete lining and enters the tunnel. There is. For this reason, a water impermeable membrane storage chamber is provided at the rear of the shield machine, and a tubular water impermeable membrane is pulled out from the ring-shaped outlet at the rear end of the water impermeable membrane storage chamber to the excavation ground side to form the water impermeable membrane and the mold. Filling of concrete between frames has come to be performed.

[0004]

However, when the impermeable membrane is pulled out from the impermeable membrane storage chamber to the excavated ground side through the ring-shaped outlet, the impermeable membrane outlet communicates with the concrete placing portion side. The concrete poured in will penetrate into the machine through the outlet. In order to prevent this infiltration, a sealing material is attached to one of the facing peripheral wall surfaces that form the outlet, and the impermeable membrane is pulled out while being pressed against the other facing peripheral wall surface. The impermeable membrane will be damaged by contact, and groundwater and earth and sand will infiltrate the pouring concrete from the damaged part, making it impossible to achieve the intended purpose.

In order to prevent such damage of the water impermeable membrane, the pressure contact force of the sealing material may be reduced, but this has a problem that it cannot withstand the pressure of the concrete to be filled at a high pressure. An object of the present invention is to provide a sealing device in a shield machine that can completely solve such problems.

[0006]

In order to achieve the above object, a sealing device in a shield machine according to the present invention is provided with a water impermeable membrane storage chamber at a rear portion of a shield machine body, and a rear end of the water impermeable membrane storage chamber. The impermeable membrane in the storage room is drawn out from the ring-shaped outlet formed in the section, and the concrete filled between the formwork and the excavated ground assembled on the rear side of the shield machine is covered with the impermeable membrane. In such a shield machine, the inner and outer sealing materials whose tips are in contact with each other are mounted on the facing surfaces of the inner and outer cylindrical walls forming the outlet of the impermeable membrane, and the space between the tip surfaces of these inner and outer sealing materials is mounted. Is configured to be pulled out while sandwiching the impermeable membrane.

Further, in the sealing device configured as described above, in the invention described in claim 2, the inner and outer sealing materials are formed tongue-shaped in cross section, and the pressurizing chamber is provided in at least one of these sealing materials. Is provided to expand and contract in the radial direction by applying a fluid pressure to the pressurizing chamber, and the invention according to claim 3 provides a sealing material having the pressurizing chamber. A pair of inner and outer sealing materials are disposed on the rear side before and after the entrance and exit, respectively, and the invention according to claim 4 relates to a space between the inner and outer sealing materials and the outer peripheral surface of the rear trunk of the shield machine on the rear side. The pressurized fluid is supplied to the void.

[0008]

Operation: A form is assembled on the inner peripheral surface of the tunnel extending from the rear part of the shield machine to the rear part for a suitable length, and the cylindrical impermeable membrane is pulled rearward from the storage chamber through the outlet as the shield machine advances. At this time, the water impermeable film is pulled out without being slidably contacted with the inner and outer cylindrical walls in a state of being sandwiched between the tip ends of the seal material mounted on the facing surfaces of the inner and outer cylindrical walls of the outlet. Further, when the space between the impermeable membrane and the mold is filled with concrete through a filling port provided at an appropriate position of the form, the filled concrete is drawn to the outlet side along the inner peripheral surface of the impermeable film. It flows but is prevented from entering the machine by the inner and outer sealing materials.

Further, as described in claim 2,
If the inner and outer sealing materials are formed tongue-shaped in cross section and at least one of the sealing materials is expanded by applying a fluid pressure, the crimping force of both sealing materials is adjusted according to the pressure at the time of filling concrete. Therefore, it is possible to reliably prevent the infiltration of concrete despite the large concrete filling pressure. As described in claim 3,
By providing a pair of inner and outer sealing materials before and after the entrance and exit, the water impermeable film can be pulled out in a more stable state.

Further, as described in claim 4,
If the pressurized fluid is supplied to the space between the inner and outer sealing materials and the outer peripheral surface of the rear body of the shield machine on the rear side thereof, the impermeable membrane is pressed against the excavated ground by the pressurized fluid. The ground can be prevented from collapsing, and the pressure can be increased at the time of compaction of the concrete so that the concrete is pressed against the placement site side, and the rotation of the concrete toward the outlet side can be prevented.

[0011]

Embodiments of the present invention will now be described with reference to the drawings.
Reference numeral 1 denotes a shield machine main body, which is composed of a front body 2 for excavating the ground, a middle body 3 having a storage chamber 6 for a cylindrical water impermeable membrane 5, and a rear body 4 having an assembly space for a formwork 7. ing. The storage chamber 6 provided in the middle case 3 has an annular front wall plate 3c fixed between front ends of an outer cylinder 3a having the same diameter as the front case 2 and an inner cylinder 3b having a small diameter and a short length. It is formed by fixing an annular rear wall plate 3d to the rear end of the cylinder 3b, and a short cylinder whose rear end reaches the rear end of the outer cylinder 3a toward the rear edge of the rear wall plate 3b. An inner peripheral wall 3e for forming an outlet formed of a body is integrally provided, and a rear portion of the outer cylinder 3a facing the inner peripheral wall 3e is used as an outer peripheral wall, and a ring-shaped impermeable film outlet 8 is formed between the facing surfaces of these inner and outer peripheral walls. Has been formed.

On the opposing surfaces of the inner and outer cylindrical peripheral walls forming the outlet 8, a pair of front and rear seal members 9 and 10 whose front and rear portions are in contact with each other at their front and rear portions, and a rear seal member 1
1 and 12 are installed all around. In these inner and outer seal materials, the inner and outer seal materials 9 and 10 at the front part are constituted by brush seals, while the inner and outer seal materials 11 and 12 at the rear part are formed.
Is composed of an elastic seal packing such as rubber having a tongue-shaped cross section. Further, in the inner and outer seal members 11 and 12 on the rear side, the inner seal member 12 mounted on the outer peripheral surface of the inner peripheral wall 3e has the inner peripheral surface center portion in the outer radial direction as shown in FIGS. The front and rear ends of the ring portion 12a which is curved to form the pressurizing chamber 13 between the inner peripheral wall 3e and the inner peripheral wall 3e are fixed to the inner peripheral wall 3e, and the ring portion 12a extends diagonally rearward from the center of the outer peripheral surface. A protruding sealing portion 12b having a tongue-shaped cross section, and the outer peripheral surface of the sealing portion 12b is elastically pressed against the outer sealing material 11.

A pressure fluid supply passage 14 such as compressed air is provided in the inner peripheral wall 3e forming the outlet 8, and one end of the passage 14 communicates with the pressurizing chamber 13 and the other end. A pressure fluid supply source (not shown) from the inside of the storage chamber 6 to the end side
It is made to communicate through appropriate piping. Further, an appropriate position of the inner cylinder 3b of the storage chamber 6 is formed with an openable / closable lid portion so that the impermeable membrane 5 can be supplied into the storage chamber 6. This impermeable membrane 5 is an annular membrane having a constant width in the tunnel length direction,
The water impermeable membrane 5 is pulled out first by the welding device 15 provided in the storage chamber 6 and is welded to and integrated with the rear end peripheral edge of the water impermeable membrane 5 so as to be pulled out from the outlet 8.

The rear body 4 of the shield machine body 1 is composed of a cylindrical body having a diameter slightly smaller than that of the front body 2 and the middle body 3, and an outer peripheral edge of an annular support plate 4a is integrally formed at the front end thereof. A connecting cylindrical portion 4b is integrally provided so as to project forward on the outer peripheral portion of the front surface of the support plate 4a, and the front half of the connecting cylindrical portion 4b is located inside the inner peripheral wall 3e of the outlet 8. The seal packing 16 is provided so as to be opposed to the peripheral surface and intervene between the opposed surfaces so as to be slidable back and forth and capable of bending.

A plurality of propulsion jacks 17 and middle folding jacks 18 are alternately arranged in the connecting cylinder portion 4b at appropriate intervals in the circumferential direction, and the middle folding jacks 18 have their front ends described above. The outlet 8 is fixed to the rear surface of the rear wall plate 3d, and the rod end is pivotally attached to the front surface of the support plate 4a of the rear body 4 so as to be tiltable in the radial direction. On the other hand, the propulsion jack 17 is fixed to the inner peripheral surface of the connecting tubular portion 4b, and its rod is exposed to the inside of the rear body 4 through a through hole penetrating the support plate 4a. It is integrally fixed to the front surface of the ring-shaped press ring 19 being formed.

The formwork 7 is assembled from the inner peripheral side of the rear surface of the press ring 19 in the rear body 4 at the rear, and the concrete filling formed between the formwork 7 and the inner peripheral surface of the rear body 4 is filled. On the front end side of the space portion 20, a ring-shaped gable plate 21 whose inner and outer peripheral end surfaces are in sliding contact with the facing surfaces of the form 7 and the rear case 4 is arranged, and the press jacks are mounted in a plurality of outer peripheral portions of the press ring 19. The rod end of 22 is fixed to the front surface of the end plate 21, and the end plate 21 is moved back and forth by the operation of the press jack 22. Reference numeral 23 is a concrete injection port that is provided in a proper position in the form frame 7 between the inner and outer peripheral surfaces.

A pressurizing fluid supply port 24 communicating with the outer peripheral surface side of the connecting cylinder portion 4b is provided at an appropriate position in the rear half of the connecting cylinder portion 4b. Of the pressurized fluid 25. Further, as shown in FIG. 2, a supply pipe 26 for supplying a fluid substance having a viscosity such as grease is attached to an appropriate position on the outer peripheral surface of the middle body 3, and the pipe 26 is connected to the front and rear of the outer sealing material 11 at the rear portion. A low-pressure fluid substance 29 is supplied through front and rear through holes 27, 28 formed in the middle body 3 in the space, and the impermeable membrane 5 is strongly applied to the inner surface of the middle body 3 by the pressurized fluid 25 supplied in the rear space. Fluid material that prevents pressure contact and supplies into the front space
By 29, the outer side of the brush seal material 9 is filled. In addition, also in the brush seal material 10 on the inside of the front part, although not shown, the inner peripheral wall 3c forming the outlet 8 is formed.
The fluid substance 29 is configured to be supplied into the front space portion through the inside.

At the front end of the opening of the front body 2 of the shield machine main body 1, a cutter head 31 which is rotated by a motor 30 is arranged, and a front end of a conveyor 35 is placed in a soil intake chamber 32 excavated by the cutter head 31. The front end of the front body 2 and the front end of the middle body 3 are connected by a center folding jack 33 arranged in the circumferential direction so as to be bendable. There is.

In order to construct a cast-in-place concrete lining while covering the tunnel excavated by the thus constructed shield machine with the water impermeable film 5, the propulsion jack 17 is extended and the cutter head 31 is rotated. After excavating a tunnel of a certain length, when the rod of the propulsion jack 17 is contracted, the press ring 19 advances and the rear body 4
Reaching the rear surface of the support plate 4a of the rear body 4a, as shown in FIG.
The following formwork assembly space portion 20 is provided therein.

As shown in FIG. 3, a new mold frame 7 is assembled in the space 20 and then the injection port provided in the mold frame 7.
The space 34 between the rear body 4 and the form 7 is filled with concrete 34 from 23 and poured. As the concrete 34 is cast, the rod of the propulsion jack 17 is extended to dig a tunnel portion having a predetermined length as shown in FIG. That is, the propulsion jack 17
When the rod of is extended, the shield machine main body 1 advances due to the reaction force of the press ring 19 that is in contact with the front end surface of the form 7, and the concrete 34 filled in the space 20 is moved along with the advance. The cylindrical water impermeable membrane 5 is drawn out together with the frame 7 rearward from the rear body 4 through the outlet 8 from the storage chamber 6 and passes between the outer peripheral surface of the rear body 4 and the excavated ground. To cover the filled concrete 34.

The concrete 34 sent rearward from the rear body 4 tries to infiltrate into the gap between the outer peripheral surface of the rear body 4 and the excavated ground, but the infiltration is from the pressurized fluid supply port 24 to the rear side. The inner and outer seal members 11, 12 are supplied by the pressurized fluid 25 injected and filled in the space between the inner and outer seal members 11, 12 and the rear end portion of the rear body 4.
The inner and outer seal members 11 and 12 are prevented from penetrating into the impermeable membrane storage chamber 6 side. In this case, since the concrete 34 is filled according to the propulsion of the shield machine main body 1, the pressure to infiltrate into the outer peripheral side of the rear body 4 is small, so that the injection pressure of the pressurized fluid 25 is low and the rear portion The expansion pressure of the inner sealing material 12 is weakened to reduce the sandwiching pressure of the impermeable membrane 5 by the inner and outer sealing materials 11 and 12, and the impermeable membrane 5 is smoothly pulled out.

As described above, when the concrete 34 is filled while being excavated by the shield machine main body 1, a portion where the concrete 34 is not sufficiently filled occurs on the front end side in the body portion 4 and the filled concrete 34 is in a consolidated state. Therefore, when the shield machine body 1 is dug to a certain length and a certain amount of concrete 34 is poured onto the form 7, the shield machine body 1 is once stopped, and as shown in FIG. The rod of the press jack 22 is extended to push the ring-shaped gable plate 21 backward.

By pushing out the end plate 21, the concrete 34 cast in the space 20 is pressed backward on the form 7, and the pressed concrete 34 presses the impermeable membrane 5 against the excavated ground side. While being consolidated, it flows into the gap between the rear body 4 and the impermeable membrane 5. This flow pressure is higher than the infiltration pressure at the time of filling the concrete, and therefore the injection pressure of the pressurized fluid 25 is made high to increase the pressure of the fluid 25 between the rear body 4 and the impermeable membrane 5. Of the sealant 12 and increase the pressure of the air injected into the pressure chamber 13 of the sealant 12 to increase the expansion pressure of the sealant 12, thereby increasing the adhesion force with the outer sealant 11 and increasing the pressure fluid.
It prevents the entry of 25 and concrete 34 into the aircraft.

When the compaction of the concrete 34 thus filled is completed and properly hardened, the press jack 22 is actuated to draw the end plate 21 toward the original position of the press ring 19 and the rod of the propulsion jack 17 is contracted. The press ring 19 is returned to the front end of the rear body 4. By this return, an assembly space portion for the mold 7 is provided in the rear body 4,
Again, the next formwork 7 is assembled between the existing formwork 7 extruded rearward from the rear body 4 and the press ring 19 in the same manner as above, the rod of the propulsion jack 17 is extended, and the tunnel is excavated. The water-impermeable membrane 5 is sent to the rear, and the space 20 between the formwork 7 and the rear body 4 is filled with concrete 34.

[0025]

As described above, according to the sealing device in the shield machine of the present invention, the tip end portion is provided on the opposing surface of the inner and outer cylindrical walls forming the outlet of the water impermeable membrane storage chamber provided in the shield machine body. Are equipped with inner and outer sealing materials that can contact each other, and are configured to pull out while holding the impermeable membrane between the tip surfaces of these inner and outer sealing materials, so that the impermeable membrane has inner and outer cylindrical walls of the outlet. It can be pulled out smoothly without sliding on the ground, and therefore the impermeable membrane can be prevented from being damaged and groundwater, earth and sand, etc. can be reliably prevented from entering the tunnel. The sealing material can also prevent the concrete filled in the space between the drawn impermeable membrane and the mold from entering the inside of the machine.

Further, since the inner and outer sealing materials are formed to have a tongue-shaped cross section and at least one of the sealing materials is made to expand by applying a fluid pressure, the expansion pressure is increased during the concrete filling. The impermeable membrane can be smoothly pulled out by reducing the holding pressure of the impermeable membrane by the inner and outer seal materials, and when the filled concrete is consolidated, the expansion pressure is increased to move the space between the inner and outer seal materials into the machine. It is possible to more reliably prevent the infiltration of concrete.

Further, if the pressurized fluid is supplied to the space between the inner and outer seal materials and the outer peripheral surface of the rear body of the shield machine on the rear side thereof, the impermeable film is formed by the pressurized fluid. It is possible to prevent the collapse of the ground by pressing it against the excavated ground, and by making the pressure large during concrete consolidation, the concrete is pressed against the place of placing,
Not only can concrete be prevented from turning to the outlet side, but also good concrete lining can be performed.

[Brief description of drawings]

FIG. 1 is a simplified vertical sectional side view of the entire shield machine,

FIG. 2 is a vertical cross-sectional side view of a main portion in a state where a press ring is moved forward to provide a mold frame assembly space portion;

FIG. 3 is a vertical cross-sectional side view of a main part during concrete filling,

FIG. 4 is a vertical cross-sectional side view of a main part in a state where the shield machine is advanced,

FIG. 5 is a vertical sectional side view of a main part during concrete consolidation,

FIG. 6 is an enlarged cross-sectional view of a rear inner and outer sealing material.

[Explanation of symbols]

 1 Shield machine main body 5 Impermeable membrane 6 Storage room 7 Formwork 8 Drawout port 9-12 Sealing material 13 Pressurizing chamber 17 Propulsion jack 20 Concrete filling space 25 Pressurized fluid

Claims (4)

[Claims] 1. An impermeable membrane storage chamber is provided at a rear portion of a shield machine main body, and the impermeable membrane in the storage chamber is drawn out from a ring-shaped outlet formed at a rear end portion of the impermeable membrane storage chamber. In a shield machine in which concrete filled between a formwork assembled on the rear side of the machine and the excavated ground is covered with the impermeable film, an inner and outer cylindrical shape forming the outlet of the impermeable film In a shield machine, characterized in that inner and outer seal members whose tip portions are in contact with each other are attached to opposing surfaces of the wall, and the water impermeable film is sandwiched between the tip faces of these inner and outer seal members and pulled out. Sealing device. 2. The inner and outer seal members are formed tongue-shaped in cross section, and at least one of the seal members is provided with a pressurizing chamber, and fluid pressure is applied to the pressurizing chamber to expand and contract in the radial direction. The sealing device in a shield machine according to claim 1, wherein 3. The pair of inner and outer sealing materials are respectively arranged before and after the outlet, and the sealing material having a pressurizing chamber is arranged on the rear side. Sealing device for the shield machine described. 4. The pressurizing fluid is supplied to a space between the inner and outer seal members and the outer peripheral surface of the rear body of the shield machine on the rear side thereof. Sealing device for the shield machine described.