JPH0469278B2 - - Google Patents

Description

[Detailed Description of the Invention] <<Industrial Application Field>> The present invention relates to a method for constructing a shield tunneling machine, and in particular, a method for constructing a shield tunneling machine while ensuring watertightness between the shield tunneling machine and segments disposed on its inner periphery. This invention relates to a method of constructing a shield excavator for tunnel excavation.

<<Background of the Invention>> When planning a shield tunnel with a large cross section and a long distance of several kilometers, it is necessary to improve the safety and reliability of conventional construction.

By the way, one of the problems with the conventional shield excavation method is that muddy water flows from the front face of the shield tunnel along the outer circumferential surface of the shield tunneling machine to the back side of the shield. It is stated that water leakage may occur inside the shield tunneling machine.

In order to prevent this, in the past, as shown in Utility Model Publication No. 52-46845 and Utility Model Application Publication No. 55-85188, improvements have been made to the material and mounting structure of the tail seal (also called tail seal). It has been.

<Problems to be Solved by the Invention> However, even with these improvements, wear and tear is unavoidable because the tail seal generates sliding friction with the segment surface every time the shield tunneling machine excavates. Particularly when long-distance shield excavation as described above is carried out, there is a limit to its wear resistance. In addition, when the tail seal becomes worn out, the tail seal is always located at the rear of the shield excavator and is hidden between the segments.
Replacement work is difficult, and there is great concern that water leakage may occur due to insufficient water-stopping properties midway through the process.

This invention was made based on the above background, and is a shield tunneling machine that eliminates the need to replace the tail seal due to wear and tear even when excavating long-distance shield tunnels, and that can easily ensure water-tightness throughout the entire construction process. The purpose is to provide a construction method.

<<Means for Solving the Problem>> In order to achieve the above object, the present invention arranges a plurality of rows of tail seals at predetermined intervals in an annular manner on the inner periphery of the skin plate of a shield excavator, and the skin plate This is a construction method for a shield excavator that excavates a tunnel by sequentially moving the assembly position of the segments in the tunnel forward in the excavation direction. When worn out,
moving the assembly position of the segment forward;
The present invention is characterized in that a new tail seal located forward of the worn tail seal is used.

Here, the predetermined interval is the interval at which, when tunneling is performed using one tail seal, another new tail seal does not cause sliding friction with the segment, that is, the interval that is equal to or greater than the width of the piece of the segment. means. Note that this distance does not necessarily need to be maintained between adjacent tail seals, and other tail seals may be arranged at such a distance.

《Operation》 When the tail seal in use wears out and loses its water-stopping properties, by assembling the segment at the position of a new tail seal placed in front of it, the tail seal can be stopped without having to replace the tail seal. Can ensure water-based properties.

<<Example>> Hereinafter, an example of the present invention will be described in detail using the drawings.

FIGS. 1 and 2 show an embodiment of a shield construction method using a shield excavator 1 according to the present invention.

In the figure, a shield tunneling machine 1 has an earth pressure chamber 4 connected to the front and rear parts of a cylindrical skin plate 2 by partition walls 3.
and a tail portion 2A.

A large diameter cutter disk 5 is installed in front of the earth pressure chamber 4.
is located.

The cutter disk 5 is rotated by rotation of a drive shaft 6 provided at the cylindrical center of the skin plate 2, and is adapted to take excavated soil into the earth pressure chamber 4 while excavating the front face.

A gear 7 is provided on the drive shaft 6, and this gear 7 meshes with a pinion provided on a drive motor 8, so that it can be rotated by the drive of the drive motor 8.

Furthermore, a reaction force jack 10 that extends and contracts toward the tail portion 2A side is provided at the peripheral edge of the earth pressure chamber 4, and a press ring 10A provided at the tip of the reaction force jack 10 projects toward the rear end side. This allows for excavation.

Further, in the tail portion 2A, the drive shaft 6
A guide shaft 11 is disposed coaxially with the guide shaft 11, and a winding device 12 is disposed on the guide shaft 11 so as to be able to turn around the guide shaft 11 and move forward and backward.

The winding device 12 has a segment 1 disposed on the inner periphery of the rear part of the tail part 2A, overlapping with the tail part 2A.
This involves assembling 4 pieces.

A first tail seal 15, a second tail seal 16, and a third tail seal 17 are arranged on the inner circumference of the tail portion 2A at intervals equal to or larger than the width of the piece of the segment 14 from the rear end. Arranged.

In each figure, the tail seals 15, 16, 17 are shown only at two locations, upper and lower, but these are all arranged annularly on the inner circumference of the skin plate 2.

In the above configuration, in the initial state of the shield tunneling machine 1, the segments 14 are assembled at a relatively rear portion of the tail portion 2A of the skin plate 2, as shown in FIG. Therefore, segment 1 as shown in the figure
4 and the tail portion 2A of the skin plate 2 is sealed only by the first tail seal 15, which prevents muddy water or underground water from entering from the rear end of the skin plate 2. Backfill concrete C is poured around the outer periphery.

By extending the reaction force jack 10 from the state shown in FIG. 1 and pressing the press ring 10A against the most advanced segment 14, the shield excavator 1 moves relatively forward due to the reaction force. This forward motion is performed at a pitch according to the width interval of the segments, and the first
Only the tail seal 15 of is in sliding frictional contact with the segment 14.

By alternately repeating this shield digging operation, segment assembly, and backfilling injection of concrete C, the first tail seal 15 is gradually worn out, and its watertightness is eventually impaired.

Therefore, as shown in FIG. 2, the segment 14 is assembled by moving forward to a position corresponding to the second tail seal 16, and the first tail seal 15, which is already worn out, is left in that state. be done. Further, the winding device 12 moves forward along the guide shaft 11 in response to this, and assembles the segments 14 at that position.

Similarly, if the second tail seal 16 is worn out, the third tail seal 17 may be used.

Note that the number of tail seals arranged is not limited to this example, and can be set depending on the degree of wear caused by the number of times of sliding and the shield digging distance, and the length of the tail portion 2A of the skin plate 2 can also be set accordingly. Can be set.

Further, as for the spare tail seals provided inside the first tail seal 15, either the necessary number of spare tail seals should be prepared by predicting the number of sliding operations in advance, or the spare tail seals should be arranged each time in consideration of the degree of wear and tear of the first tail seal 15. You can also do this.

<<Effects of the Invention>> As explained in detail above, in the method for constructing a shield tunneling machine according to the present invention, the worn tail seal can be replaced by sequentially moving the assembly position of the segments in the skin plate. Water-tightness can be easily ensured by using a new tail seal without having to go through the difficult task of cleaning the tail seal.

Therefore, according to the present invention, especially when constructing a long-distance shield tunnel, by taking into consideration the number of excavations depending on the distance and the degree of wear of the tail seal, the sealing effect can be maintained during the entire process of shield excavation, thereby preventing water leakage. It can prevent accidents such as
Safety can be further improved.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the shield tunneling machine according to the present invention, and FIG. 1 is a cross-sectional view showing a state in which the seal between the segment and the skin plate is performed by the rearmost first tail seal. Figure 2 shows the seal between the same skin plate and the segment.
It is a sectional view showing a state in which the seal tail is used. 1...Shield excavator, 2...Skin plate, 2A...Tail part, 14...Segment, 1
5...First tail seal, 16...Second tail seal, 17...Third tail seal.

Claims (1)

[Claims] 1. On the inner periphery of the skin plate of the shield tunneling machine,
A construction method for a shield excavator that excavates a tunnel by arranging multiple rows of tail seals at predetermined intervals in an annular manner and sequentially moving the assembly position of the segments in the skin plate forward in the excavation direction. When the tail seal is worn out due to sliding friction with the segment as the shield tunneling machine moves forward, the assembly position of the segment is moved forward and a new tail seal located ahead of the worn tail seal is installed. A method of constructing a shield excavator, which is characterized in that it is used.