JPH0583099U - Tail seal structure of shield machine - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a tail seal structure for a shield machine, which can increase the brush width (seal width) without increasing the tail clearance and can improve the water blocking performance. In a tail seal structure in which water is stopped between a shield frame 2 and a segment 8 by a wire brush 10, a tubular wire brush mounting seat 9 extending in the axial direction is provided on the shield frame 2, and the wire It is characterized in that the wire brush 10 is attached to the inner surface of the brush attachment seat 9 toward the inner side in the radial direction of the shield frame 2.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a tail seal structure of a shield machine, and more particularly to a novel tail seal structure capable of enhancing water blocking performance.

[0002]

[Prior Art]

 Generally, a tail seal of a shield machine is equipped with a tail seal, and groundwater from the side ground and backfill material (mortar, etc.) filled in the gap between the segment and the ground flows into the shield machine. It is designed to prevent

As shown in FIG. 5, this kind of tail seal has a plurality of stages (two stages in the illustrated example) on the tail plate b provided at the rear end of the shield frame a, with intervals in the excavation direction. The wire brush c is formed, and an injection pipe e for injecting a water blocking filler d (putty grease or the like) between the wire brushes c.

The wire brush c is attached along the inner wall of the tail plate b through a U-shaped base plate f that is welded to the inner surface of the tail plate b, and the tip side of the wire brush c holds the wire brush c. It is bent in the middle by the sandwiched thin steel plates g and is brought into sliding contact with the outer surface of the segment h.

On the other hand, the injection pipe e extends from the main body of the machine (not shown) along the outer wall of the shield frame a to a substantially intermediate position between the wire brushes c, c and is formed in the tail plate b. The filling material d for stopping water is injected into the space defined by the segment h from i, the tail plate b, and the wire brushes c and c.

According to this configuration, the filling material d and the wire brush c filled in the space cooperate to exert a sealing effect, so that groundwater, earth and sand, backfill material, etc. from the natural ground side j into the aircraft. Will be blocked.

[0007]

[Problems to be solved by the device]

 By the way, in recent years, the demand for large-depth and long-distance tunnels such as subsea tunnels has increased, and the number of cases of shield excavation under high water pressure (seawater pressure) or high earth pressure is increasing. In this case, in the conventional seal using the wire brush c and the filler d, there is a possibility that the waterproofness and the pressure resistance are insufficient. As a countermeasure against this, increasing the brush width k (seal width) of the wire brush c can be considered.

However, in the wire brush c, since the root portion c ₁ that determines the brush width k is attached inside the tail plate b in the radial direction of the shield frame a, the brush c is no longer provided. _If the laminated thickness ₁ of 1 is increased, the wire brush c cannot be bent inward in the radial direction on the way, and the sealing function is significantly deteriorated. That is, the wire brush c has a brush width k that is almost full at present, and it is difficult to increase the brush width k further.

Although this problem can be solved by increasing the tail clearance m, this is not realistic because the effective tunnel diameter (segment diameter) becomes small.

The object of the present invention, which was devised in consideration of the above circumstances, is to increase the brush width (seal width) without increasing the tail clearance and to improve the water stoppage. Tail seal for shield machine To provide the structure.

[0011]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention provides a shield frame with a tubular wire brush mounting seat extending in the axial direction in a tail seal structure in which water is stopped between a shield frame and a segment by a wire brush. The wire brush is mounted on the inner surface of the wire brush mounting seat so as to face inward in the radial direction of the shield frame.

[0012]

[Action]

 According to the tail seal structure having the above configuration, since the root portion of the wire brush is attached along the axial direction of the shield frame, the brush width (seal width) can be increased irrespective of the tail clearance.

[0013]

【Example】

 An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a side sectional view of a tail portion 1 of a shield machine. As shown in the figure, two stages of intermediate wire brushes 4a and 4b are provided on the inner surface of a tubular tail plate 3 welded to the rear end of the shield frame 2 and spaced apart in the excavation direction. These intermediate wire brushes 4a, 4b are provided with meshes 5a, 5b inside thereof, and are attached along the inner wall of the tail plate 3 via a base plate 6 having a U-shaped cross section, respectively. The tip end side is bent inward in the radial direction by a thin steel plate 7 sandwiching the wire brush 4 and slidably contacts the outer surface of the segment 8.

At the rear end of the tail plate 3, a cylindrical wire brush mounting seat 9 extending in the axial direction is welded to the shield frame 2. A wire brush 10 and a mesh 11 are attached to the inner surface of the wire brush attachment seat 9 at right angles to the attachment seat 9 inward in the radial direction of the shield frame 2 by being sandwiched between thin steel plates 12. The brush length / mesh length of each wire brush 10 / mesh 11 is longer than the length at which the tip of the brush 10 / mesh 11 abuts on the segment 8, and is about 1.5 times as long in the illustrated example. , It is becoming longer from the front to the rear in the direction of excavation. Therefore, the tip end of the wire brush 10 and the mesh 11 hits the segment 8 and is deformed backward by the excavation of the shield machine.

FIG. 2 is a perspective sectional view of the vicinity of the wire brush mounting seat 9. As shown in the figure, the wire brush mounting seat 9 is formed of a ring body having a U-shaped cross section and formed coaxially with the shield frame 2. That is, the wire brush mounting seat 9 includes a ring-shaped bottom plate 9a extending in the axial direction of the shield frame 2 and an inner plate 9b and an outer plate 9c which are squarely welded to both ends of the inner surface of the bottom plate 9a. It consists of As shown in FIG. 1, the thickness of the bottom plate 9a is formed thinner than that of the tail plate 3, which makes the difference in plate thickness from that when the wire brush 10 is directly attached to the inner surface of the tail plate 3. That is, the brush length of the wire brush 10 is earned. The brush mounting seat 9 is not integrally formed over the entire circumference, but is divided into a plurality of pieces in the circumferential direction in consideration of the assemblability, and they are manufactured by connecting them in the circumferential direction. To be done.

As shown in FIG. 2, a wire brush 10 and a mesh 11 are attached between thin plates 12 between an inner plate 9 b and an outer plate 9 c of the brush mounting seat 9. Concretely, the wire brush 10 and the mesh 11 are folded back by a core wire 13 arranged on the bottom plate 9a of the brush mounting seat 9, and a bolt that hangs the core wire 13 between the inner plate 9b and the outer plate 9c. Alternatively, it is mounted by preventing the pin 14 from falling off. The core wire 13 is arranged in the circumferential direction of the bottom plate 9a, and the bolts or pins 14 are attached at predetermined intervals in the circumferential direction.

The thin steel plate 12 is formed such that its length is slightly shorter than the brush length of the wire brush 10 and its width is a predetermined width (about 10 to 30 cm), and the width direction, that is, the circumferential direction of the shield frame 2. The plates 12 adjacent to each other are arranged so as to overlap each other. Further, the thin steel plate 12 is formed of a material having a spring property so that the thin steel plate 12 is easily bent when its tip comes into contact with the segment 8. In addition, as shown in FIG. 1, a protrusion 15 is provided at the front end of the tail plate 3 so as to be located on the back surface of the inner plate 9b of the brush mounting seat 9. As shown in FIG. 3, the projection 15 functions as a support point for the segment 8 during the curve excavation, and the wire brush 10 is sandwiched between the mounting seats 9, 9b, 9c and the segment 8 during the excavation. It is intended to prevent falling off.

On the other hand, as shown in FIG. 1, on the outer side of the tail plate 3, a water blocking filler (putty grease) is provided in each of the spaces defined by the wire brushes 4 a, 4 b, 10 and the tail plate 3 and the segment 8. Etc.) is provided with an injection pipe 17. The injection pipe 17 is extended from the machine body along the outer wall of the shield frame 2 to a substantially rear end of the tail plate 3, and the water is injected into the space from the injection port 18 formed in the tail plate 3. The filling material 16 is injected. The filling material 16 filled in this space impregnates the wire brushes 4a, 4b, 10 and the meshes 5a, 5b, 11 with each other, and they cooperate to exert a sealing effect. Intrusion of groundwater, earth and sand, backfill material, etc. is prevented.

The operation of this embodiment having the above configuration will be described.

According to the tail seal structure having the above-described structure, since the root portion 10a of the wire brush 10 is laminated along the bottom plate 9a of the brush mounting seat 9 extending in the axial direction of the shield frame 2, the bottom plate 9a is formed. When the width of the brush is widened to increase the laminated thickness 20, the brush width 22 (seal width) can be increased irrespective of the tail clearance 21. As a result, the water-stop sealing property will be improved, and it will be possible to cope with large-depth and long-distance excavation such as undersea tunnels. In this embodiment, the wire brush 10 is used only for the first brush at the end of the excavator, but it goes without saying that it may be applied to the intermediate wire brushes 4a, 4b in FIG.

Further, the filler 16 filled in the space defined by the wire brushes 4a, 4b, 10 adheres to the surface of the segment 8 and relatively moves backward in the excavation direction by the excavation of the excavator. , Tries to spread between the rear wire brushes 4b and 10 and the segment 8 to leak from the space, but according to the present embodiment, the wire brush 10 and the thin steel plate 12 are mounted at right angles to the excavation direction. Therefore, the tips of the wire brush 10 and the thin steel plate 12 are strongly pressed against the segment 8, and the amount of leakage of the filling material 16 is reduced. That is, the filler 16 that adheres to the surface of the segment 8 and leaks from the space due to the excavation is scraped by the wire brush 10 and the thin steel plate 12 and held in the space. Therefore, there is an economic effect that the consumption of the filler 16 is reduced.

A modified embodiment of the present invention is shown in FIG. As shown in the figure, this modified embodiment is different from the previous embodiment only in that the inner plate 9b and the outer plate 9c of the wire brush mounting seat 9 are attached to the bottom plate 9a with a slight inclination to the rear side in the excavation direction. Different. According to this configuration, the wire brush 10 mounted between the inner plate 9b and the outer plate 9c is slightly bent toward the rear side in the excavation direction, and prevents buckling deformation toward the front side in the excavation direction. To be done. Needless to say, the same actions and effects as those of the previous embodiment can be obtained. Alternatively, only the inner plate 9b may be attached to the bottom plate 9a at a right angle to enhance the scraping effect of the filler 16 attached to the surface of the segment 8.

[0024]

[Effect of the device]

 As described above, according to the tail seal structure of the present invention, the wire brushes are laminated along the axial direction of the shield frame. Therefore, if the laminated thickness is increased, the brush width (seal The width can be made thicker, and thus the waterproof sealing performance can be improved.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a tail seal structure of a shield machine as an embodiment of the present invention.

FIG. 2 is a perspective view of an essential part of FIG.

FIG. 3 is a diagram showing how the shield machine of FIG. 1 excavates a curve.

FIG. 4 is a side sectional view showing a main part of a modified embodiment of the present invention.

FIG. 5 is a side sectional view of a tail seal structure of a shield machine as a conventional example.

[Explanation of symbols]

 2 Shield frame 3 Tail plate 8 Segment 9 Wire brush mounting seat 10 Wire brush 11 Mesh

Claims (1)

[Scope of utility model registration request] 1. In a tail seal structure in which water is stopped between a shield frame and a segment by a wire brush, a tubular wire brush mounting seat extending in the axial direction is provided on the shield frame, and the wire brush mounting seat is provided. A tail seal structure for a shield machine, characterized in that a wire brush is attached to the inner surface of the wire inward in the radial direction of the shield frame.