JPH0978990A - Tail seal structure of shield machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the tail seal structure of a shield machine excellent in water stop performance and durability. SOLUTION: A wire brush seal 13 is formed by holding both sides of a wire brush between a flexible outer protective plate 17 and an inner protective plate 19 and injecting foam resin into a wire part of the wire brush. A base plate 21 is fitted to the inner side face of a tail plate 9 by welding. Three rows of annular wire brushes 15a, 15b, 15c form the wire brush seal 13, and back-filling material 27 or the like filled in a part behind the rearmost wire brush 15c in the third row is prevented from infiltrating into a shield machine 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tail seal structure for a shield machine.

[0002]

2. Description of the Related Art Recently, when a shield machine is used to construct a tunnel or the like, as shown in a schematic configuration diagram of the shield machine 101 in FIG.
3 excavation is performed, and the segment 107 is assembled behind the inside of the skin plate 105.
The shield machine 101 propels by taking a reaction force from 7.

At the tail portion F behind the shield machine 101,
In order to prevent ground water, muddy water, backfill material, etc. from entering between the skin plate 105 and the segment 107 of the shield machine 101 into the shield machine 101, the tail portion F is sealed (tail seal). A rubber seal or a brush seal was used for this tail seal.

The wire brush type tail seal, which is commonly used, has a small water blocking effect by itself. Therefore, in order to improve the water blocking effect of the wire brush type tail seal, the tail seal grease is packed inside.
Furthermore, in order to further improve the water blocking effect and durability, the tail seal grease is continuously and intermittently injected through a segment grout hole or a dedicated injection pipe incorporated in the shield machine 101.

[0005]

However, the conventional wire brush seal has the following problems. That is, (a) in the method of packing the grease in the wire brush, the grease is squeezed out of the tail seal as the tail clearance decreases or as time passes, but it is difficult to additionally inject the tail seal grease into the tail seal. is there.

(B) When the backfill material intrudes into the tail seal and solidifies due to a change in clearance or the like, the elasticity of the tail seal is reduced, and the clearance cannot be followed due to the clearance change. May cause water leakage. (C) When the clearance becomes small, excessive force may be applied to the tail seal, which may damage the tail seal.

(D) Due to the backing of the shield machine, the inner protective plate of the tail seal is broken, and thereafter the wire itself constituting the brush is also bent and cut into a hook shape. The present invention has been made in view of such a problem, and the purpose thereof is to have good waterproofness and durability,
An object of the present invention is to provide a tail seal structure of a shield machine.

[0008]

To achieve the above object, the present invention provides a tail seal structure for sealing a tail portion of a shield machine, wherein a wire brush is provided inside a tail portion of a skin plate of the shield machine. A tail seal structure of a shield machine is characterized in that a foam resin is injected into the inside of the wire brush to form a wire brush seal.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described in detail below with reference to the drawings. Figure 1 shows the first
It is a cross-sectional view showing a schematic configuration of a shield machine 1 according to the embodiment of. 5 in front of the shield machine 1 by the cutter 3
Excavation is performed, the segment 11 is assembled on the inner surface of the tail plate 9 behind the skin plate 7, and a reaction force is taken from the segment 11 to propel the shield machine 1 in the excavation direction A.

A tail plate B at the rear of the shield machine 1 has a skin plate 7 and a tail plate 9, and a segment 1
Shielding machine for groundwater, muddy water, backfill material, etc.
In order to prevent the wire brush seal 13 from entering the inside, an annular wire brush seal 13 is provided on the entire inner surface of the tail plate 9.

Next, the wire brush seal 13 will be described. 2 is an enlarged view of the portion B in FIG. 1, showing in detail the structure of the wire brush seal 13 and its surroundings in a sectional view, and FIG. 3 is a partial development view showing the arrangement of the wire brush seal 13. The wire brush seal 13 is one in which both sides of the wire brush 15 are sandwiched between a flexible outer protection plate 17 and a flexible inner protection plate 19, and foamed resin is injected into the wire portion of the wire brush 15.

A base plate 21 covers the entire root portions of the outer protective plate 17 and the inner protective plate 19. The base plate 21 is attached to the inner surface of the tail plate 9 with rivets 23. Reference numeral 25 is a protection ring.

Three rows of annular wire brushes 15a, 15
b and 15c constitute the wire brush seal 13 as a whole. In a portion of the wire brush 15c behind the outer protection plate 17, a backing material 27 such as mortar is injected between the ground 5 and the segment 11. Ground 5 and segment 1
There is an external fluid such as muddy water or groundwater between 1 and 1, but most of the external fluid is blocked by the wire brush 15 in the third row and slightly invades the external fluid. The animals also have wire brushes 15b, 15a in the second and first rows.
Therefore, it does not enter the inside of the shield machine 1.

In the shield machine 1, the wire brush seal 1
At 3, the tail plate 9 and the segment 11 are sealed to prevent the external fluid from entering the inside of the shield machine 1, and the excavation in the excavation direction A is continued. Further, the shield machine 1 may return to the direction opposite to the excavation direction A due to the backing, but since the wire brush seal 13 is flexible, it can be dealt with without breaking.

Next, the injection of the foamed resin into the wire brush 15 will be described. FIG. 4 is a view showing a method for manually injecting the foamed resin, and shows a cross section of a portion C-C in FIGS. 1, 2 and 3. However, the segment 11 is not shown in FIG. FIG. 5 is an enlarged view showing a method for manually injecting the foamed resin, and FIG. 6 is a wire brush 1.
It is a figure which shows the state at the time of operation of 5c.

First, after attaching the wire brush seal 13 to the shield machine 1, the wire brush 15 having a predetermined injection width at the lowest position is provided with a cover such as gum tape 35. The gum tape 35 is provided so as to cover the side surface of the outer protective plate 17, the tip portion of the wire brush 15, and the side surface portion with the inner protective plate 19 so that the foamed resin is injected only inside the gum tape 35. belongs to.

Next, from the opening provided in the duct tape 35,
The inlet of the funnel 31 is inserted into the wire brush 15, and the foamed resin is poured into the wire brush 15 from the foamed resin container 33 through the funnel 31. The foamed resin naturally diffuses and fills the gap between the brush portions of the wire brush 15 (mixed portion 37 in FIG. 6). Further, between the wire brush 15 and the gum tape 35, a portion (foamed resin portion 39 in FIG. 6) made of only foamed resin is generated. The foamed resin gels 10 to 20 minutes after the injection.

The above-mentioned injection work is carried out by three rows of wire brushes 15.
a, 15b, 15c, respectively, and after the foamed resin has gelled, the shield machine 1 is moved by the width of one injection into the wire brush 15, for example, as shown in D of FIG.
Roll in the direction. Then, the portion adjacent to the previously implanted portion of the wire brush 15 is implanted in the same procedure. Therefore, the foamed resin is injected into the wire brush 15 manually by repeating the cycle of injection into the wire brushes 15 in three rows-gelation-rotation in the D direction-injection into the adjacent portion. In the example of FIG. 4, a portion indicated by a thick arc is the injected portion E, and when the injection is performed once, the foamed resin is continuously filled over the entire annular wire brush 15.

After the injection of the foamed resin and the gelation on the entire circumference of the wire brush 15 are completed, the shield machine 1 starts excavation. As shown in FIG. 6, during operation, the wire brush 15 is pressed against the segment 11, and the angle with respect to the tail plate 9 becomes smaller than that of the wire brush 15 during injection shown in FIG. Therefore, the wire brush 15
The whole works as a spring and is strongly pressed against the segment 11. Therefore, the tail plate 9 and the segment 11
Even if the distance (clearance) between
A reliable seal can be made.

The shape of the wire brush tip is such that the segment 1 is pressed against the outer peripheral surface of the segment 11.
It is designed in advance so that it will adhere to a wide area. In the example of FIG. 6, the tip portion of the wire brush 15c and the foamed resin portion 39 are in close contact with the segment 11 over a wide area, and prevent the backing material 27 from entering.

FIG. 7 is a diagram showing the characteristics of the foamed resin. The foamed resin is a mixture of a liquid as a base material and a liquid as a foaming agent. In the present embodiment, the apparent density is 0.12 g / cm 3 on average, and the 50% compressive strength is 0.27 on average.
A product having a kgf / cm2 and an average closed cell rate of 37% was used. The foamed resin is made flame-retardant by adding a flame retardant.

In the wire brush seal 13, the wire brush 15 and the foamed resin are integrated and wear-resistant, and the wire brush 15 is responsible for the strength, and the injected foamed resin is responsible for the waterproofness and elasticity. When the shield machine 1 backs and returns in the direction opposite to the digging direction A, the wire brush seal 13 is difficult to bend in the opposite direction because the wire is restrained in the elastic body. Therefore, it is possible to prevent the wire from being pushed out in the opposite direction and broken due to the backing.

As described above in detail, since the wire brush seal 13 according to the first embodiment has a large water blocking effect, it is not necessary to additionally inject the tail seal grease, so that the injection amount can be greatly reduced. Is possible.

Further, the wire brush seal 13 can flexibly cope with changes in the tail clearance, and water leakage is unlikely to occur even when the tail clearance is large. In addition, the wire brush seal 13 can exhibit waterproofness even under high water pressure.

The wire brush seal 13 is a backing material 27.
Is a material that does not easily enter, and has a flexible structure that is strong against the backing of the shield machine 1, so that it is less likely to be damaged, and it is possible to dig a long distance without replacing the wire brush seal 13, which is economical. The overall construction period of the shield work can be shortened. In the present embodiment, the wire brushes 15 are provided in three rows.
It is also possible to provide only four rows, or only four rows.

Next, a second embodiment will be described. The second embodiment is almost the same as the first embodiment, but the foamed resin is not injected inside the shield machine, but the foamed resin is injected in advance in a factory or the like as shown in FIG. . FIG. 8 shows a method of injecting foamed resin into one wire brush piece 51. The wire brush piece 51 includes, for example, a wire brush 53 having a width of 10 cm or 20 cm and an outer protection plate 55 and an inner protection plate 57.
It is sandwiched between. A large number of wire brush pieces 51 are arranged side by side, and each wire brush 53
The foamed resin is injected into the gap between the brushes with the funnel 59.

The foamed resin contains a liquid 61 as a base material and a liquid 63 as a foaming agent, which are pump 65 and pump 67, respectively.
In this case, a predetermined amount is pumped up and mixed by the mixer 69. A flame retardant (not shown) is added to the mixer 69 to make the foamed resin flame-retardant.

FIG. 9 partially shows a state in which the wire brush seal 51 is formed by attaching the wire brush piece 51 in which foamed resin is injected to the shield machine 1 at the shield site. The base plate 73 portion of each wire brush piece 51 is vertically and horizontally arranged at a predetermined position on the inner surface of the tail plate 75 and fixed by welding. Since there is a gap between the wire brush pieces 51 as it is, the resin 79 is filled to form a continuous structure.

As described above in detail, in the second embodiment, the wire brush piece 51 can be prepared in advance in a factory or the like. Therefore,
At the shield site, all that is required is to attach the wire brush piece 51 and fill the gap with the resin 79, and it is possible to significantly reduce the working time and also shorten the overall construction period.

[0030]

As described above in detail, according to the present invention, it is possible to provide a tail seal structure for a shield machine, which is excellent in waterproofness, durability and work efficiency.

[Brief description of drawings]

FIG. 1 is a sectional view showing a schematic configuration of a shield machine 1.

FIG. 2 is an enlarged view of part B in FIG.

FIG. 3 is a partially developed view showing the arrangement of the wire brush seal 13.

FIG. 4 is a diagram showing a manual injection method of foamed resin.

FIG. 5 is an enlarged view showing a method for manually injecting foamed resin.

FIG. 6 is a diagram showing a state in which the third row wire brush 15c is in operation.

FIG. 7 is a diagram showing characteristics of foamed resin.

FIG. 8 is a diagram showing a method for injecting a foamed resin in a factory.

FIG. 9 is a partial development view showing a state in which the wire brush piece 51 is attached to the shield machine 1.

FIG. 10 is a schematic configuration diagram of the shield machine 101.

[Explanation of symbols]

 1 ……… Shielding machine 3 ………… Cutter 5 ………… Solid ground 7 ………… Skin plate 9 ………… Tail plate 11 ………… Segment 13 ………… Wire brush seal 15 ………… Wire brush 17 …… Outer protection plate 19 Inner protection plate 21 Base plate 23 Rivet 25 Protection ring 27 Backing material 31 Funnel 33 Foam resin container 35 Duct tape 37 ………… Mixed portion 39 ………… Foam resin portion 51 ………… Wire brush piece 53 ………… Wire brush 55 ………… Outside protection plate 57 ………… Inside protection plate 59 ………… Rot 65, 67… …… Pump 69 ………… Mixer 71 ………… Wire brush seal 73 ………… Base plate 75 ………… Tail plate 77 ………… Rivets

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuya Sasaki 1-3-8 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd. Tokyo Branch Office (72) Inventor Hiromasa Igarashi 2-chome, Tobita, Chofu-shi, Tokyo No. 1 Inside the Technical Research Institute of Kashima Construction Co., Ltd. (72) Inventor Fumio Imanate No. 19-1 Tobita, Chofu-shi, Tokyo Inside the Technical Research Institute of Kashima Construction Co., Ltd. No. 7 Kashima Construction Co., Ltd.

Claims (5)

[Claims] 1. A tail seal structure for sealing a tail part of a shield machine, wherein a wire brush is provided inside a tail part of a skin plate of the shield machine, and foamed resin is injected into the wire brush to form a wire brush seal. The tail seal structure of the shield machine, which is characterized by that. 2. The tail seal structure for a shield machine according to claim 1, wherein the foamed resin is a mixture of a base material and a foaming agent. 3. The tail seal structure for a shield machine according to claim 2, wherein the foamed resin further contains a flame retardant. 4. The tail seal structure for a shield machine according to claim 1, wherein the foamed resin is injected into the wire brush after the wire brush is attached to the shield machine. 5. The tail seal structure for a shield machine according to claim 1, wherein the foamed resin is injected into the wire brush in a factory, and the wire brush is attached to the shield machine on site.