JPH033797B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a seal structure for a starting port formed in the wall of a shaft for propulsion of a seal tunneling machine.

(Prior art) When propelling a seal excavator from the starting point of a shaft,
In order to prevent excavated soil and groundwater from flowing into the shaft from the starting port, a seal structure as shown in FIGS. 1 and 2 has conventionally been placed on the shaft wall 12 defining the starting port 10.

In this seal structure, an annular elastic sealing material 16 having a circular hole 16a with a smaller diameter than the outer diameter of the shield body 14 is arranged concentrically with the starting port 10, and the back side of the sealing material 16 is made of a rectangular metal plate. A plurality of metal fittings 18 are arranged around the starting port 10 at intervals. The sealing material 16 and the metal fitting 18 are fixed to the shaft wall 12 by an anchor bolt 20 and a fixing device such as a nut 22 screwed into the anchor bolt.
A long hole is provided through which the hole passes.

When the shield tunneling machine starts propulsion, the sealing material 16 is bent in the direction of propulsion of the shield body 14, as shown by the chain line in FIG. come into contact with Thereby, the space between the shield body and the wall defining the starting port is sealed, and the inflow of excavated soil, ground water, etc. from the starting port 10 is prevented.

When the shield tunneling machine is further propelled, the inner circumferential edge of the sealing material 16 comes into contact with, for example, the outer circumferential surface of a lining segment continuing behind the shield body 14. By the way, large earth water pressure from the excavated earth and sand, underground water, etc. acts on the sealing material 16. However, the outer diameter of the lining segment is smaller than the outer diameter of the shield body 14, and the contact area between the seal material 16 and the lining segment is smaller than that between the seal material 16 and the shield body 14. Then, each metal fitting 18 is moved until its tip comes into contact with the outer peripheral surface of the lining segment. Thereby, each metal fitting 18 supports the sealing material 16 on its back surface so that the sealing material 16 can maintain the bent state and resist the earth water pressure.

However, each metal fitting is moved by hitting them all at once, which not only requires a large number of people, but also causes a time delay in moving each metal fitting, which may result in an incomplete seal at the launch port. .

(Objective) Therefore, an object of the present invention is to enable the starting port to be reliably sealed without manual intervention.

(Structure and Effects) The present invention has a circular hole having a diameter smaller than the outer diameter of the shield body, and an elastic sealing material disposed on the mine wall so that the circular hole and the starting port are concentric. ,
a plurality of metal fittings arranged at intervals around the starting port on the back side of the sealing material, and a fixture for fixing the metal fittings and the sealing material to the mine wall, each of the metal fittings having a plurality of metal fittings disposed at intervals around the starting port; A first plate fixed to the mine wall by a fixture and a second plate swingably connected to the first plate, and during propulsion, the tip of the second plate is attached to the shield body or the rear thereof. It is characterized by contacting the outer circumferential surface of the tunnel lining material that follows.

According to the present invention, when the shield tunneling machine is propelled, the second plate rotates angularly in response to the thrust, and its tip portion contacts the outer peripheral surface of the shield body or tunnel lining material that is being propelled. Therefore,
The rotation angle of the second plate is maintained, thereby supporting the sealing material.

(Example) The present invention is characterized by the following description of the example shown in FIGS. 3 to 6.
It will become clearer.

Referring to FIGS. 3 and 4, a seal structure 30 according to the present invention is applied to a circular starting port 38 formed in a shaft wall 36 of a shaft 34 for propulsion of a shield tunneling machine 32. .

The shield tunneling machine 32 has a cut head 4 in front.
0 is rotatably attached to the shield body 42
is installed in the shaft 34 concentrically with the starting port 38, which is formed to have a larger diameter than the outer diameter of the shield body 42. Behind the shield body 42, a lining segment 44 having a smaller outer diameter is arranged concentrically with the shield body 42. A tail seal 46 is attached to the inner rear end of the shield body 42 in order to seal between the shield body 42 and the lining segment 44. The shield tunneling machine 32 can be propelled by extending a plurality of jacks 48 fixed to the inner wall of the shield body 42 toward the front end of the lining segment 44, using the jacks 48 as reaction force supports. The shield tunneling machine may be propelled by any other method. As an example, there is a method in which a plurality of jacks (not shown) for propelling the lining segment 44 are arranged behind the lining segment 44 and these jacks are operated to propel the shield excavator.

The shield tunneling machine may be of a so-called manual digging type or a mechanical digging type, and the tunnel lining material is not limited to the lining segments, but may be, for example, a pipe body. The pit wall 36 defining the starting port 38 is formed of cast-in-place concrete. Instead of this cast-in-place concrete, it can also be formed from a precast concrete plate, steel material, or the like.

A sealing material 50 having elasticity, such as a rubber plate, forming the sealing structure 30 is disposed on the shaft wall 36 . The sealing material 50 has a circular hole 50 having a diameter smaller than the outer diameter of the shield body 42 and the lining segment 44.
a, and the center of the circular hole 50a is on the axis of the starting port 30.

On the back side of the sealing material 50, that is, behind it,
A plurality of metal fittings 52 are arranged at intervals around the starting port 38.
is located. Each metal fitting 52 has a sealing material 50
and a pair of washers 54 are fixed to the shaft wall 36 by a fixture 56.

The metal fitting 52 includes a first plate 52a fixed to the pit wall 36 by an anchor bolt 56a constituting the fixing device and a nut 56b screwed into the anchor bolt 56a.
and a second plate 52b which is pivotally attached to the first plate via a pin 58 and is swingable thereby.

The anchor bolt 56a passing through the sealing material 50 and the first plate 52a is attached to the shaft wall 36 by embedding one end in concrete when the shaft wall 36 is formed. When the pit wall is formed of a precast concrete plate, a socket is embedded in the precast concrete plate in advance, and one end of the bolt is screwed into the socket and a nut is screwed into the other end. Further, when the pit wall is made of steel, for example, bolts are welded to the pit wall and nuts are screwed together. In either example, the fixture may have another structure as long as it can fix the sealing material 50 and the metal fittings 52 to the shaft wall.

The metal fitting 52 is connected to the second
The tip of the plate 52b is positioned and arranged so as to contact the outer circumferential surface of the shield body 42 and the outer circumferential surface of the lining segment 44. As will be described in detail later, as a result, when the shield excavator 32 is propelled and passes through the launch port 38, the second plate can rotate in response to the thrust. Metal fittings 5
2, the first plate 5
It is desirable that the through hole 60 of the anchor bolt 56a provided in the anchor bolt 2a be an elongated hole extending toward the second plate instead of a round hole.

Also, the first plate 5 protrudes like a claw from the second plate 52b toward the first plate.
By attaching a stopper 62 that can come into contact with the back surface of plate 2a, it is possible to restrict rotation of second plate 52b in the opposite direction to the rotational direction.
The stopper 62 can be composed of, for example, a pair of plates, and may be either integral with the second plate 52b or separate from the second plate 52b. A non-protruding portion of the plate, ie a portion extending along the back side of the second plate, reinforces the second plate. Note that it is optional whether or not the portion reinforcing the second plate is made to protrude to the side opposite to the stopper 62.

Next, the function of the seal structure 30 according to the present invention is as follows.
This will be explained with reference to FIGS. 5a to 5c, which focus on the metal fitting 52 located at the top end. First, when the shield tunneling machine 32 is located behind the metal fitting 52 (FIG. 5a), the second plate 52b is simply suspended in the vertical direction. shield tunneling machine 32
When the shield body 42 starts propulsion and passes through the starting port 36 (Fig. 5b), the tip of the second plate 52b comes into contact with the outer peripheral surface of the shield body 42, so the second plate 52b receives the thrust and starts clockwise. angularly rotated in the direction and maintained at that rotation angle. At this time, the sealing material 50 is bent forward, and the circular hole 50a of the sealing material is pushed out so that the edge thereof comes into close contact with the outer peripheral surface of the shield body 42. As a result, the second plate 52b supports the sealing material 50 while being in contact with the back surface of the sealing material 50, and the starting port 38
is sealed.

When the shield excavator 32 is further propelled and the tip of the second plate 52b contacts the lining segment 44, the outer diameter of the lining segment 44 is smaller than the outer diameter of the shield body 42, so the second plate 5
2b is rotated slightly counterclockwise from said rotational angular position and maintained in that angular position (FIG. 5c);
Similarly to when the shield body 42 passes through the starting port 38, the sealing material 50 is securely held by the second plate 52b, and the starting port 38 is sealed.

Further, as shown in FIG. 6, when the propulsion direction of the shield excavator 32 changes due to a sudden change in the geology and becomes eccentric, the second plate 52b comes into contact with the outer peripheral surface of the shield body 42 or the lining segment 44. It may become impossible. However, stoppa 62
is in contact with the back surface of the first plate 52a and prevents the second plate 52b from further rotating counterclockwise from the vertical position. Therefore, it is supported. Therefore, there is no possibility that the sealing material 50 on which the earth water pressure is applied is bent in the opposite direction and excavated soil, groundwater, etc. leak out.

As described above, the second plate 52b is preferably provided with a stopper 62, but if the second plate 52b does not have a stopper, it is necessary to prevent the second plate 52b from rotating under no load when the metal fittings are installed.
It is desirable to tightly pivot the first and second plates to each other in advance.

According to the seal structure according to the present invention, the second plate of the metal fitting constituting the second plate is swingable, and its tip comes into contact with the outer peripheral surface of the shield body or tunnel lining material that is being propelled. The second plate follows the propulsion of the shield tunneling machine and automatically and reliably holds the sealing material from behind.

Furthermore, even if the shield tunneling machine is eccentric and the second plate cannot come into contact with it, the rotation of the second plate is restricted by the stopper provided on the second plate, and the sealing material is prevented from becoming unretained. be able to.

[Brief explanation of the drawing]

1 and 2 are a side view and a vertical sectional view, respectively, of a conventional seal structure, and FIGS. 3 and 4 are a side view and a longitudinal sectional view, respectively, of a seal structure according to the present invention, and FIGS. 5a and 5b. Figures 5c and 6 are explanatory views of the seal structure at the top, respectively. 30: Seal structure, 32: Shield excavator, 3
4: Pit, 36: Pit wall, 38: Starting port, 42: Shield body, 44: Lining segment, 50: Seal material, 52: Metal fittings, 52a, 52b: First and second plates, 56: Fixing tool, 62: Stoppa.

Claims (1)

[Claims] 1. A seal structure for a starting port formed in the wall of a shaft for propulsion of a shield tunneling machine, which has a circular hole with a smaller diameter than the outer diameter of the shield body, and has a circular hole with a smaller diameter than the outer diameter of the shield body. an elastic sealing material disposed on the mine wall so as to be concentric with the starting port, and a plurality of metal fittings arranged at intervals around the starting port on the back side of the sealing material; a fixture for fixing the metal fitting and the sealing material to the mine wall; each metal fitting includes a first plate fixed to the mine wall by the fixture; and a first plate swingably connected to the first plate. 2
plate, wherein during propulsion, the tip end of the second plate comes into contact with the outer peripheral surface of the shield main body or the outer peripheral surface of a tunnel lining material continuing behind the shield main body. 2. The pit wall is formed of cast-in-place concrete, and the fixing device includes an anchor bolt embedded in the pit wall and extending through a hole drilled in the first plate, and a nut screwed thereto. A seal structure according to claim 1. 3. The shaft wall is formed of a precast concrete plate, and the fixture is screwed into a socket embedded in the shaft wall, and the fixture is screwed into the socket.
A seal structure according to claim 1, further comprising a bolt extending through a hole drilled in the plate. 4. The seal structure according to claim 1, wherein the second plate has a stopper that can come into contact with the back surface of the first plate.