JPS6172196A - Method of excavating horizontal pit in method of shielding construction and shielding excavator thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for excavating a horizontal shaft using a shield method that allows the cross section of excavation to be enlarged, and a shield excavator therefor.

(Conventional technology) Possible methods of expanding the shield excavation cross section without creating a new shaft include mechanically changing the excavation diameter of the shield excavator itself and expanding the segment after constructing the shield. .

(Problems to be Solved by the Invention) However, the former method has the disadvantage that the structure of the shield tunneling machine is complicated, making manufacturing, maintenance, etc. complicated, and also leading to high costs. Furthermore, if the debtor enlarges the segment after constructing the shield, there is a drawback that the construction work is extremely complicated.

(Means for Solving the Problems) The present invention has been proposed in view of the above points, and by making the underground side bonding part of the shield tube have a double structure, it can be easily used as needed in the horizontal shaft excavation process. It is an object of the present invention to provide a method for excavating a horizontal shaft using a shield method capable of expanding a horizontal shaft from a small diameter to a large diameter, and a shield excavator therefor.

(Structure of the invention) Hereinafter, the present invention will be explained along with the drawings.

Figures 1 (a) and 1 (b) show an embodiment of a shield tunneling machine according to the present invention.This shield tunneling machine improves the sealing effect even though the number of sealing members is reduced and the sealing mechanism is simplified. It is a type of shield ε advance machine that is easy to maintain and also aims to reduce costs.

In other words, numeral 1 in the figure is a cylindrical shield tube with a relatively large diameter, and this seal 1 (tube 1
An outer peripheral partition wall portion 2 is formed extending toward the radial center of. The outer peripheral partition wall 2 has a substantially ring shape, and an earth pressure gauge 3 is provided in a part thereof.

The rear portion 1A of the shield tube 1 has a double structure, and a cylindrical shield tube double structure portion 1B is detachably provided in the inner portion. The shield tube double structure part 11S at the mouth is designed so that a segment S with a small diameter can be assembled inside the shield R:11 which is made to fit a large segment outer diameter (not shown). Support member 1 provided on the inner circumferential portion of the cylindrical bond square portion 1A
Attach the rear part 1 of the shield cylinder to G via fixing means such as Pol I-B.
It is constructed so that it can be easily attached to or detached from A.

Also, its outer circumference and shield I! A reinforcing member 111 of an appropriately configured structure is provided between the I11 side portion 1A and the inner periphery thereof, and a tail seal 1B is provided at the rear, and a tail seal 1B is provided to prevent excavated earth and sand from entering the interior. A seal member 1E is provided between the shield cylinder rear portion 1A and the tail seal 111. Further, a shield jack A is provided at a slightly inner position of the rear portion 1A of the shield cylinder.

Reference numeral 4 denotes a rotary cutter rotatably provided at the front end opening of the shield tube 1, which extends in a Narita shape from a central boss 5 toward the outer periphery, and is connected to each other by a reinforcing member 6a. A spoke 6, a pit 7 protruding from the front of the cutter spoke 6, a mixing bowl 8 provided at the rear of the outer periphery of the cutter spoke 6, and a viscosity imparting material jet provided from the front of the boss 5. The cutter spoke 6 has a central pit 10 provided with an outlet 9, and an intermediate support member 11 is connected to the substantially central rear portion of the cutter spoke 6.

Reference numeral 12 denotes a drive motor for rotating the rotary excavator A, which is fixed to a frame 13 appropriately provided within the shield cylinder 1 within the shield excavator main body, and this drive motor 12 and the intermediate support member 11 and is connected via a rotation transmission +11 connection. That is, this rotation transmission structure includes a gear portion 15 provided at the drive motor 12,
A gear part 16 that can mesh with this gear part 15 is provided on the rear outer periphery, and a supporting member 17 is provided at the front end thereof.
It is mainly composed of an intermediate support member 11 and a rotary transmission member 18 having a cylindrical shape.

Reference numeral 19 denotes a disk-shaped central partition wall that is connected to the intermediate support member 11 and rotates integrally with the intermediate support member 11, and constitutes a central bulkhead.
is provided on the rear end side of the intermediate support member 11, and the outer peripheral end side of the central partition wall part 19 faces the inner peripheral end side of the outer peripheral partition wall part 2 formed on the shield cylinder 1 side, and the central partition wall part 19 A rotating portion 19 atf is provided at the rear of the outer peripheral portion of the central partition wall portion 10 , and the inner peripheral end side of the central partition wall portion 10 is supported by a bearing 20 .

Therefore, a seal member 21 is provided between the outer surface of the rotating portion 19a and the rotating portion 2a on the shield cylinder 1 side, which is formed at the inner peripheral end of the outer peripheral partition wall portion 2 and is disposed opposite to the rotating portion 19a. is provided.

Reference numeral 22 denotes a center shaft that is provided approximately at the center of the shield tube 1, penetrates approximately the center of the central partition wall 19, and is rotatable independently of the rotary excavator A-. A bearing 20 provided approximately at the center of the partition wall 19 and a bearing 2 provided approximately at the center of the frame 13.
3, and its front end is loosely connected to the boss 5 constituting the rotary excavation material, and an arm 24 is provided on the outer periphery of the front end to protrude radially toward the intermediate support member 11 side. At the front and rear of this arm 24, there is a face chamber 2 defined by an outer peripheral partition wall 2, a central partition wall 19, etc.
A mixing blade 26 is provided for stirring the central part of the 5.

Reference numeral 27 denotes a drive motor capable of forward and reverse rotation for driving the center shaft 22, and is fixed to the frame 13. The drive shaft of the drive motor 27 and the center shaft 22
is connected to the center shaft 2 by a gear mechanism 28, and by driving the drive element 21, the kneaded garbage@26 connected to the center shaft 22 via the arm 24 is connected to the center shaft 2.
It is configured to rotate substantially concentrically with 2.

The earth removing device is of a well-known construction and has a front end connected to the lower part of the face chamber 25, and is equipped with a cylindrical body 30 and a screw conveyor 31 rotatably provided within the cylinder body 30. There is. Moreover, 32 is a sealing member provided between the rear of the circumferential surface 19a and the main body of the shield tunneling machine. 3
3 is an erector used when assembling segment S
134 is a perfect circle holding machine.

Next, the present invention will be explained in detail.

As shown in FIG. 2, the shield tunneling machine main body is launched toward the final opening FL (not shown) through a shaft opening 36a formed in the shaft wall 36 of the starting shaft 35.

The entrance gasket 37 can be used when the shield tunneling machine body starts, but as shown in Figure 3, when the tail portion of the shield tunneling machine body passes through the entrance gasket 37, the outer diameter of the shield and the outside of the segment Since the difference in diameter (tail void amount) is large, the packing 37 does not work effectively. For this reason, after the tail part of the shield tunneling machine body passes through the entrance packing part, the water stop plate 38 that fits the large tail void is placed at the mine entrance 3, as shown in FIG.
6a. In addition, excavation of the ground is carried out using a rotating cutter. That is, when the drive motor 12 is driven, the rotation of the drive motor 12 is caused by the gear portions 15° and 16.
, is transmitted to the rotatable central partition 19 via the rotation transmitting member 18, the support member 17, etc., is further transmitted to the intermediate support member 11 connected to this central partition 19, and is transmitted to the boss 5 having the central bit 10. The connected cutter spokes 6 rotate, thereby excavating the face via the central bit 10, hitter 7, etc. In this case, an appropriate viscosity imparting material is injected from the viscosity imparting material spout 9 depending on the soil quality.

Thus, the excavated soil, viscosity imparting material, etc. are taken into the face chamber 25, and the excavated soil, etc. on the inner and outer periphery of the face chamber 25 are stirred by the mixing unit 8.

On the other hand, the excavated earth and sand in the center of the face chamber 25 are removed by the drive motor 2.
7.1fi11! The mixture is stirred by a purging mixer 26 protruding from an arm 24 that is driven via a mechanism 28, center shirts 1 to 22, and the like. In this case, since the cutter spokes 6, the intermediate support member 11, the central bulkhead, etc. rotate together, the excavated earth and sand that exists between them tends to move around. However, if the drive motor 27 is operated to rotate the mixing rabbit 26 in the center in the opposite direction to the cutter spoke 6, the following rotation will not occur and the excavated earth and sand in the face chamber 25 will be mixed while colliding with each other. Excellent stirring effect can be obtained.

Then, shield jack A is added to the excavated soil that has been mixed.
This is to generate earth pressure through the earth pressure, thereby pressing down the face, and excavating the main body of the shield b advance machine while appropriately removing earth through the earth removal device f29.

Note that, for example, the segment 1-3 having a diameter of 6000101 is sequentially assembled behind the shield tube double structure part IB (7) as the excavation progresses. Furthermore, since the shield tube 1 has a larger diameter than the shield tube double structure portion 1B, a backfilling material 39tf is injected into the void r4gB generated on the outer periphery of the segment S.

In this case, since the difference between the shield outer diameter and the segment outer diameter is large, it is preferable to use excavated earth and sand mixed with a hardening agent as the backfilling material 39. Therefore, a plant for mixing this backfilling material 39 is provided inside the shield mine.

FIG. 4 shows a method and device for mixing excavated earth and sand with a hardening agent. A screw conveyor 40 is connected to a five-cylinder body 30, and this screw conveyor 40 has two drive motors 41 at the front and rear, respectively. .12 is provided, and the screws 43 and 44 in the front and rear parts can be rotated independently, and the front screw 43 is provided with a rotation function of 11 degrees, and the rear screw 44 is a notched screw. It is constructed to have the functions of transportation and line mixing.

Further, a curing agent input pipe 45 is connected to the rear stage portion 40a of the screw conveyor, and a delivery pump 47 having a kneaded material input port 47a is provided opposite to the discharge port 46 provided at the lower rear part. One end of an injection pipe 48 for injecting backing material is connected to this pressure pump 41, and the other end of the injection pipe 48 faces the outer periphery of the segment S. Further, a circulation pipe 50ff is provided between the injection pipe 48 and the screw conveyor front section 40b via a valve 49.

Therefore, when discharging excavated soil, the operation of the rear screw conveyor 40b for mixing the hardening agent provided at the rear is stopped, and the front screw conveyor 40a for discharging soil is rotated. When soil is mixed with a hardening agent, the gate of the soil discharge port 51 is closed, the entire screw conveyor 40 is rotated, the mixture is mixed, and the soil is continuously discharged to the pressure pump 47 via the soil discharge 046. .

A pressure pump 41 injects excavated earth and sand mixed with a hardening agent from the grout hole of the segment S through an injection pipe 48 provided in the mine.

The backfill injection method is to fill the tail void with backfill material 39, which is a mixture of excavated earth and sand and a hardening agent, while maintaining a pressure equal to the excavation earth pressure at all times, and the pressure remains constant regardless of the excavation of the shield excavation machine body. Maintain and manage injections. At this time, if the hardening time of the backing material 39 is short, it is difficult to maintain a pressurized and full state in the tail void, so it is more effective to set the hardening time as long as about half a day to one day.

As for the hardening agent, lime-based or cement-based hardening agents are generally used, but hardening agents such as those used for making blocks or simple paved roads by mixing cement, a small amount of hardening agent, and earth and sand are used. It's okay. Further, as a method for backfilling, there may be a method of injecting a hardening agent using a 15-shot method, or a method of backfilling excavated soil as a primary injection and then performing a secondary injection from the rear. It is also possible to use a commonly used backing material.

In addition, when expanding the diameter of the horizontal shaft, as shown in Figure 5,
The ground is improved in advance at the point where the finished cross section of the shield line is changed to form a ground improvement section G, and when the shield excavator itself reaches that point, backfilling is injected to prevent groundwater from entering. Next, after removing the segment 2 ring S+, 82 inside the shield tunneling machine in the ground improvement section G, the double structure section 1B is disassembled and the shield I is removed, as shown in FIG. l Attach the tail seal 10 to the rear portion 1A. Thereafter, the large-diameter segment S' is assembled via the erector 33, the perfect circle holding VA 34, etc., and the shield jack A is also reattached to a position where it can be propelled.

Furthermore, in preparation for the redevelopment of the shield tunneling machine main body, a reaction force receiver 51 is assembled inside the shield tunneling machine to ensure smooth transmission of thrust.

Coupled with the above work, inspection and repair of cutter pits 1 to 1 are carried out as necessary, and by assembling segments with a finish of, for example, 7QOOmm, it is possible to easily construct a horizontal shaft from a small diameter to a large diameter.

It goes without saying that the present invention can be implemented not only within the above range but also by other shield construction methods.

(Effects of the Invention) As described above, according to the present invention, the shield n-double structure portion 1B, which has a substantially cylindrical shape and has a smaller diameter than the shield tube 1, is detachably provided in the rear portion of the shield tube 1. Since it is possible to incorporate segments with corresponding diameters into the shield tube double structure portion 1B or the rear of the shield tube 1, the structure of the shield excavator main body does not become complicated and has a simple structure, making it easy to manufacture. Cost increases can be suppressed, and maintenance is also easy.

Further, the shield tunneling machine of the present invention can be obtained by simply attaching the shield tube double structure portion to the existing shield tunneling machine main body, and from this point of view as well, it is highly convenient.

Furthermore, if necessary, a horizontal shaft with a large diameter can be easily formed during excavation, and the workability thereof is good.

There are other effects.

[Brief explanation of the drawing]

Figure 1 shows an embodiment of the present invention, (A) is a left half front view, (A) is a left half front view, (
B) is a side sectional view, FIGS. 2 and 3 are explanatory diagrams of the operation at the time of starting or penetrating the ground, and FIG. 4 is a schematic side sectional view of the shield excavator of the present invention equipped with a backfilling material injection device. , FIG. 5, and FIG. 6 are explanatory views of the operation of enlarging the horizontal shaft. 1...Shield tube, 1A...Shield tube rear part, 1T...Shield tube double structure part, Soil...Rotary cutter, 25...Face chamber, Figure 2, Figure 3 figure

Claims (1)

[Claims] In the rear part of the shield tube 1, a shield tube double structure section 1B having a substantially cylindrical shape and having a smaller diameter than the shield tube 1 is detachably provided, and this shield tube double structure section 1B or Segments with different diameters can be incorporated at the rear of the shield tube 1, and a hardening agent is injected into the screw conveyor that discharges excavated soil, and the excavated soil and hardening agent are mixed and kneaded to form a mixed soil. A horizontal shaft excavation method using the shield method, which is characterized in that mixed earth and sand is forced into the void outside the built-in segment using an earth removal pump and injected back-filling. (2) Inside the rear part of the shield tube 1, there is a shield tube double structure section 1B that has a substantially cylindrical shape and has a smaller diameter than the shield tube 1.
A shield excavator characterized in that a shield cylinder double structure part 1B or the rear of the shield cylinder 1 can be assembled with segments having different diameters.