JPS61142294A - Discharge of air bubble mixed sludge - 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 (Technical Field of the Invention) The present invention relates to a method for discharging borium or earth and sand excavated during excavation of a shield tunnel, and in particular, to a method for reducing excavation resistance against car and dirt of the face ground or against erosion. In order to provide fluidity and water-tightness, we remove air bubbles from the air bubble treatment or air bubble treatment applied to the ground or layer in front of the bulkhead of the shield body. F relates to a method of discharging from a pressurized area in front of it to an atmospheric pressure area behind it.

(Prior art) When discharging slag from the pressurized area in front of the bulkhead to the atmospheric pressure area behind it, it is necessary to maintain a predetermined pressure in the pressurized area in front of the bulkhead, and it is necessary to maintain continuous excavation. In addition, continuous discharge of saline is desirable.

Regardless of the size of the seal tunnel diameter, i.e. the inner diameter of the tunnel, it is desirable that the bottling discharge equipment be able to secure a large amount of work space behind the bulkhead. It is preferable that this be done in
However, the conventional method for discharging copper does not meet all of the requirements in Section L.

(Objective of the Invention) Therefore, an object of the present invention is to provide a method for discharging slag that satisfies the above-mentioned requirements, and is also used to reduce the excavation resistance of the face ground to the cutter or to impart fluidity and water-tightness to steel. To provide a method for discharging porosity mixed with air bubbles.

(Structure 1 Effect) The method for discharging aerated boron according to the present invention is aimed at reducing the excavation resistance of the face ground against the cutter or imparting fluidity and water-stopping properties to the ditch in front of the bulkhead of the shield body. The method is characterized in that while a predetermined pressure is maintained in a pressurized area in front of the partition wall, the copper containing air bubbles through the air bubble treatment or air mixing process applied to the partition wall is pumped through the discharge pipe to the atmospheric pressure area behind the partition wall. .

According to the present invention, since air bubbles are mixed in 1*, it has fluidity and watertight properties, and the inside of the discharge pipe communicating with the pressurized area in front of the partition wall is maintained at a predetermined pressure within the pressurized area. It flows smoothly while maintaining the flow rate, and can be pumped to the desired location through the discharge pipe to the atmospheric pressure area behind the bulkhead, such as inside an excavated tunnel, a shaft for shield launch, or a hopper installed on the ground. .

Pressure-feeding the thread through the discharge pipe can eliminate the need for transporting the thread by using pits in the mine and lifting the thread in the shaft, and can also expand the working space in the mine, thereby increasing work safety. Furthermore, I! ! Continuous discharge of iron becomes possible, @
This makes it possible to shorten the carrying-out process and, in turn, to perform continuous excavation and thereby shorten the construction period. Furthermore, while maintaining a predetermined pressure in the pressurized area in front of the bulkhead, the air is pumped through the discharge pipe that communicates with the pressurized area, so the stability of the face is not compromised, and the pressure is maintained through the discharge pipe. Sato is easy to measure its emissions and is advantageous for various controls for safe excavation. moreover,
The working environment can be improved without the inside of the mine becoming dirty due to the iron or the noise caused by the removal of the iron.

Further features of the invention will become clearer from the following description of an illustrated embodiment.

(actual example) A shield type tunnel excavation device t shown in FIG.

is equipped with a jack 16 at the rear of the shield body 12 that causes the segments 14 to carry a reaction force to propel the shield body, and at the front part supports 71 and 18 on the rotary cutter and controls the forward force inside the shield body. A partition wall 24 is provided that divides into a pressure region 20 and a rear atmospheric pressure region 22.

A foaming agent supply pipe 28 having a plurality of openings 26 extending from the cutter face toward the face is connected to the cutter head 18 through its axis of rotation. Further, a plurality of foaming agent supply pipes 30 are connected to the partition wall 24, and the ends of each supply pipe are connected to the front of the partition wall so as to supply air bubbles to the threads placed in the threads or to cause foaming in the threads. There is an opening 32 for supplying the foaming agent. Further, the partition wall 24 is provided with a plurality of agitators 34 in order to promote stirring and mixing of the borium and the foaming agent.

According to the conventional excavation equipment described above, the excavation resistance of the cutter is reduced by the generation or mixing of air bubbles in the earth and sand by the action of the agent supplied from the cutter face, and the excavated earth and sand are The air bubbles contained therein or caused by the action of the agent supplied to the excavated soil on the partition wall side fluidize the thread. In addition, this porcelain has a sludge-like shape and is highly liquid-tight and airtight, so it is
It has the property that it is advantageous in venting to the atmospheric pressure region 22 without causing a pressure drop in the region 20.

According to the example shown in FIG. 1, a screw conveyor 36 installed in the atmospheric pressure region 22 is attached to the partition wall 24 so that the inside communicates with the pressurizing region 20. This screw conveyor 36
constitutes an intermediate discharge area for discharging the borage from the pressurized area 20 in front of the bulkhead to the atmospheric pressure area 22 behind, and the screw conveyor is supplied with antifoaming agent therein via its casing 38 and shaft 40. A device 42 is connected.

The supply device 42 includes an antifoaming agent supply source 42a and pipes 42b, 42c connected thereto.The pipes 42b, 42c are
Approximately one-third of the entire length of the screw conveyor 36 from the bulkhead side
the casing 38 so as to add the antifoam agent to the
and openings 38a8 and 40a in shaft 40, respectively.
is provided. This antifoaming agent is effective against environmental problems caused by the bubbles from the clay deposited at soil dump sites not disappearing over a long period of time, and by the increase in volume of the clay mixed with air bubbles. ,
In order to solve the problem of process-1-, it is added as appropriate to the fM-containing fiber.

The screw conveyor 36 is provided with an opening/closing part 44 at the end opposite to the W4 wall 24, and a belt conveyor 46 for discharging the metal is installed below the opening/closing part.

Face excavation inside screw conveyor 36, shield body 1
2 and the associated pressure increase in the pressurized area 22, the bubble-containing porosity is sent through the casing 38 and moves through approximately one-third of the casing 38, and then reaches the pipe 42.
When the antifoaming agent is added through b and 42c, the threads and antifoaming agent are mixed under the action of feeding and stirring caused by the rotation of the screw shaft, and as a result, the antifoaming agent is defoamed and is deposited on the face ground. Returns to the same natural soil state as before. Due to its fluidity, the aerated grain may be rapidly discharged from the screw conveyor, but by being defoamed as described above, compaction occurs and rapid discharge is prevented.

As an antifoaming agent, for example, when air bubbles are generated by using an air entraining agent consisting of a nonionic activator polyoxy compound or sulfone compound, ethyl alcohol, Pronal 2400 (trade name) manufactured by Toho Chemical Industries, etc. A surfactant or the like can be used.

The defoamed skin mixed with an antifoaming agent in the screw conveyor 36, which is the discharge area, gradually becomes compacted while moving towards the opening/closing part 44, similar to when the entire inside of the screw conveyor is filled with air bubbles. can maintain its watertight properties.

Therefore, even if the opening/closing section 44 is opened and the bubble-free state is discharged onto the belt conveyor 46 in the atmospheric pressure region, no pressure drop will occur in the pressurized region 20, and the face will remain stable. A necessary predetermined pressure can be maintained.

The example in FIG. 2 shows an example in which the discharge area communicating with the pressurizing area 20 is constituted by a rotating drum type straining device 37. This straining device is similar to that disclosed in Japanese Patent Publication No. 53-36257. It has a structure of: a casing 38 connected to the partition wall 24; and a drum 39 located inside the casing and driven and rotated; An opening 43 is provided for receiving and discharging the casing 38.
An opening/closing section 44 is provided in the opening/closing section 44 .

The pressure area 2 is compressed by clockwise angular rotation of the drum 39.
The antifoam agent fed into the opening 43 from the pipe 45 of the antifoam agent supply device 42 is added to the straw received into the drum from the opening 43 through the opening 43 through the continued rotation of the drum. Further angular rotation of the drum 39 causes the 21i
While reaching the position shown in iiiI, that is, the position where the opening 43 is aligned with the opening/closing part, the copper and antifoaming agent are stirred and mixed, and the air bubbles in the recess are extinguished. Thereafter, when the opening/closing part 44 is opened while the drum 39 is stopped at the position shown in the figure, the bubble-free silk is discharged from the drum 39 through the opening/closing part 44 of the casing onto the belt conveyor 46, and continues into the atmospheric pressure region. is carried out to the rear.

Figures 3 and 4, as well as Figures 5 and 6 showing examples of the present invention, show that the bubble-containing porosity is discharged from the pressurized area 20 with the bubbles mixed in it into the atmospheric pressure area 22 while preventing the pressure from decreasing. Afterwards, it is subjected to defoaming treatment with an antifoaming agent inside the shield body 12 or in the mine shaft, or it is pumped directly from the pressurized area to equipment installed on the ground by utilizing the fluidity of the sludge-shaped bubble-containing pit. Here, an example of release into the atmospheric pressure region is shown. Defoaming treatment is carried out after release into the atmospheric pressure region.

First, the device shown in FIG. 3 has a discharge pipe 50 that is attached to the partition wall 24 and communicates with the pressurized area 20, and has a discharge pipe 50 at its end that discharges the slag while maintaining a predetermined pressure in the pressurized area. A discharge mechanism 52 and a discharge port 54 are provided. A pore tube 56 is disposed below the discharge port 54, and the bubble-containing waste received in the discharge pipe 50 as the shield main body 12 is propelled is discharged outside the pipe in a bubble-containing state by the operation of the mechanism 52. It is carried out of the shield body by the trolley 56. After that, it is stirred and mixed with an antifoaming agent in a tank installed in the mine shaft or on the ground. As shown in FIG. 4, there is a dust reservoir connected to a defoaming agent supply device M42 in order to receive the dust under the discharge port 54 of the discharge pipe 50, add the defoaming agent thereto, and stir and mix the dust. 55
may be provided.

Referring now to Figure 5.6, which shows an embodiment of the invention,
The discharge pipe 50 of the bubble-mixed mine shown in FIG. 3 is extended and connected to an above-ground processing stage @58 via tunnels 57a and 57b. A pump 60 for pressure feeding is installed in the discharge pipe 50 , and a rotary pulp 62 is installed near the end of the discharge pipe 50 , so that the porosity containing air bubbles is absorbed by the pressure inside the discharge pipe 50 and, ultimately, in the pressurized area 20 . is discharged into the Ia reservoir 55 without any pressure drop.

In the slag reservoir 55, the antifoaming agent sent from the supply device 42 is added to the slag, and the slag is returned to a foam-free state by stirring and mixing the two, and then transferred to the hopper 64, where it is transported by a normal earth and sand transporter such as a dump truck. The soil will be transported to the dumping site by means of other means.

[Brief explanation of drawings]

Figure 1 is a schematic vertical cross-sectional view showing one example of a shield type tunnel excavation device, Figures 2.3.4 are vertical cross-sectional views showing another example of the device shown in Figure 1, and Figure 5 is a book. Figure 6 is a vertical cross-sectional view of a shield type tunnel excavation device used for carrying out the invention and the shaft behind it. FIG. 10... Shield type tunnel excavation device. 12...Shield body, 18...Cutter head, 20@-・Pressure area, 22--
・Atmospheric pressure area, 24... Life barrier. 50＠...Board discharge pipe, 55...1ili! Reservoir,
5811--Ground defoaming equipment, 60--Pump for pressure feeding, 62-e rotary valve, 64Φ working hopper. Agent Patent Attorney Nobuyuki MatsunagaFigure 1Figure 2Figure 3Figure 4

Claims (1)

[Claims] In order to reduce the excavation resistance of the face ground against the cutter or to provide fluidity and water-tightness to 2) A method for discharging air bubbles, which is characterized in that while a predetermined pressure is maintained in the pressurized region in front, the gas is pumped through a discharge pipe to the atmospheric pressure region behind the partition wall.