JPH05214893A - Seal construction between shield segments - Google Patents

Abstract

PURPOSE:To ensure watertightness by providing a plate having a circular section to the inside of the tail plate of a shield excavator, bearing ring-shaped bodies of segments so that they have approximately the same gap and, at the same time, and providing a seal device to the whole surface of the gap. CONSTITUTION:A bearing plate 9 having a circular section is placed at the inside bottom of the tail plate 2 of a shield excavator 1, and ring-shaped bodies 7 of segments 5 of reinforced concrete, etc., are borne so that they have the approximately the same gap 10. After that, a seal device 11 constituted of a rubber tube, a wire brush, a flat spring, etc., is placed to the whole surface of the gap 10. Even in the case the tail plate 3 is moved, it is so constituted that seal effect is displayed. According to the constitution, watertightness can be ensured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield structure for excavating in a shield construction method and a seal structure between a shield assembled into a ring-shaped body and a sliding segment in the shield.

[0002]

2. Description of the Related Art As is well known, the shield construction method is an excellent construction method for forming a tunnel or the like on soft ground. This method involves excavating the ground at the front while preventing the ground from collapsing with a shield made of a tubular iron plate. A tail plate made of a tubular iron plate is connected to the rear of the shield so as to be rotatable by a predetermined angle. By this rotation, the excavation direction of the tunnel can be changed. In this tail plate, segments made of reinforced concrete or the like, which have been divided and manufactured in a factory in advance, are joined to each other in an annular shape to form a ring-shaped body, and the ring-shaped body already assembled and connected to the ring-shaped body existing behind. Then, a jack is applied to this new joined ring-shaped body to advance the shield and tail plate. As a result, the ring-shaped bodies are connected in a cylindrical shape to support the ground of the tunnel.

When the tunnel is located deep below the water table, the tail plate and the tubular body are
Watertightness must be maintained through sliding movement through the sealing device.

In this sealing device for keeping watertightness, a rubber with a spring called a wire brush is provided all around the inner peripheral surface of the tail plate, and the rubber is brought into close contact with the outer periphery of the segment by a spring. A plurality of this wire brush was provided in the axial direction of the tail plate, and the gap between them was filled with grease to prevent water from entering the inside.

[0005]

In the conventional shield construction method, the outer shape of the ring-shaped body assembled by joining the segments is larger than the inner diameter of the tubular tail plate so that the sliding is possible. However, the sealing device was provided in the gap between the two. Since the ring-shaped body is placed directly on the bottom of the tail plate, the center of the ring-shaped body does not coincide with the center of the tail plate, and the center of the ring-shaped body is eccentric downward. There is. For this reason, the above-mentioned gap becomes larger toward the top and becomes zero at the bottom. Therefore, the spring of the wire brush remains bent strongly near the bottom and easily yields, so when building a long distance tunnel etc. by the shield method, the life of the spring will reach by the end of construction. , It becomes difficult to maintain watertightness under high water pressure.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a shield / segment seal structure which has a long life and can sufficiently maintain watertightness.

[0007]

In order to achieve the above object, the present invention provides a support plate having an arcuate cross section for supporting a ring-shaped body at the bottom of the tail plate, and the thickness of the support plate. By making the ring-shaped body and the tail plate substantially concentric with each other, the gap between the two is made substantially concentric around the entire circumference, and a sealing device for maintaining watertightness in this gap is provided all around.

As in the conventional case, the sealing device may be only one provided with a wire brush made of rubber with spring, or may be a device additionally provided with another type of sealing device. That is, a compressed air is enclosed in a rubber tube to make it adhere to the ring-shaped body, and a sealing device in which grease or compressed air is inserted in the other gap between the tube and the ring is provided side by side in the axial direction of the tail plate. It may be.

[0009]

By making the gap between the ring-shaped body and the tail plate substantially the same over the entire circumference, the spring of the sealing device provided in this gap can be properly bent over the entire circumference.

Further, since the gap can be kept substantially the same (constant) over the entire circumference, the sealing device is not limited to one provided with a rubber with a spring called a wire brush, and compressed air is enclosed in a rubber tube. It is also possible to install side dishes, which makes it easier to maintain water tightness. Further, by inserting grease or compressed air between the tube and the ring-shaped body, water tightness can be further ensured.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As in the overall schematic diagram shown in FIG. 4, the ground is excavated at the front of the tubular shield body 1 made of iron. At the rear of the shield body 1, there is a tubular tail plate 3 made of iron.
Are connected. Shield body 1 and tail plate 3
The hydraulic cylinder (not shown) can change the relative angle within a predetermined angle, thereby changing the direction of the tunnel to be excavated. In the tail plate 3, the concrete segment 5 is joined into a ring shape as shown in FIG. The ring-shaped body 7 newly joined and assembled in this way is connected to the already joined rear ring-shaped body 7. After that, a shield jack (not shown) is applied to the newly joined ring-shaped body 7, and the shield body 1 and the tail plate 3 are moved leftward in the figure.
The joining work, the assembling work, and the connecting work of the segments 5 are performed on the support plate 9 (FIG. 2) provided at the bottom of the tail plate 3. The support plate 9 has an arcuate cross section, and its thickness is such that the assembled ring-shaped body 7 and the tail plate 3 can be made substantially concentric (FIG. 1).

By making them concentric in this way, the gap 10 between the ring-shaped body 7 and the tail plate 3 becomes substantially the same on the entire circumference, and the sealing device 11 is provided on the entire circumference in this gap. The sealing device 11 includes two types of sealing devices 11A and 11A.
B is provided side by side in the axial direction of the tail plate 3. First
The sealing device 11A is provided with a plurality of spring rubbers called wire brushes 13 (three in FIG. 5) as in the conventional case. Each of the wire brushes 13 has a leaf spring 17 in which the rubber 15 at the tip is in close contact with the outer surface of the segment 5. The space between the wire brushes 13 is filled with grease to prevent water from entering the gap 10 from the outside.

A second sealing device 11B is provided in front of the first sealing device 11A. The second sealing device 11B is one in which compressed air is enclosed in a rubber tube 21 having two cavities 19 as shown in FIG. It is also possible that compressed air can be taken in and out. A recess 23 is formed in the center of the tube 21 in the front-rear direction.
Inject grease that has the function of preventing air and water leaks. Further, compressed air is injected between the tube 21 and the adjacent wire brush 13 to prevent water from entering.

As described above, according to this embodiment, by providing the support plate 9 between the bottom of the tail plate 3 and the ring-shaped body 7, the ring-shaped body 7 and the tail plate 3 are substantially concentric. Can be located. The gap 10 between the both 7 and 3 can be made substantially the same over the entire circumference. As a result, the mounting angle of the leaf spring 17 of the first rising seal device 11A can be made uniform and proper over the entire circumference, so that the leaf spring 17 is hard to yield and its life is extended. It is possible to increase the watertightness keeping function.

By making the ring-shaped body 7 and the tail plate 3 substantially concentric, even if the shield body 1 and the tail plate 3 rotate due to excavation, the gap 10 maintains the substantially same body over the entire circumference. You can Therefore, the second sealing device 1 using the tube 21 that is relatively weak against the change in the gap is used.
1B can also be sufficiently adopted, and the high water-tightness retaining function peculiar to the sealing device using the tube 21 can be exhibited.

Since the support plate 9 is provided on the tail plate 3, the total length of the tail plate 3 becomes longer than before, but this also brings about an advantage that the work time for joining the segments 5 and other work time in the tail plate can be lengthened.

In the above embodiment, the second sealing device 11B is provided with the tube 21 in one stage, but in other embodiments, two stages or three or more stages may be provided. It is possible.

In the above embodiment, the support plate 9
The radius of curvature of the arcuate cross-sectional view is not the same as the radius of curvature of the segment 5 (FIG. 2), but in other embodiments, the radius of curvature of both may be concentric. Is.

[0019]

As described above, according to the shield / segment sealing structure of the present invention, the gap with the tail plate of the ring-shaped body can be made substantially the same over the entire circumference, and the springs constituting the sealing device can be made uniform. It is possible to bend the spring properly, extend the life of the spring, and enhance the watertightness-retaining effect. Further, since the gap can be made substantially the same and constant over the entire circumference, the sealing device is not limited to a conventional wire brush made of rubber with a spring, and is made of a rubber having a higher watertight function and higher durability. It is possible to use a tube in which compressed air is enclosed, and it is possible to maintain higher watertightness by interposing grease or compressed air between the tube and the ring-shaped body.

[Brief description of drawings]

FIG. 1 is a horizontal cross-sectional front view (cross-sectional view taken along line AA of FIG. 4) of a tail plate portion of a shield excavator including a shield-segment sealing structure according to an embodiment of the present invention.

FIG. 2 is an enlarged view of part B in FIG. (B-B sectional view of FIG. 3)

FIG. 3 is a sectional view taken along line CC of FIG. (Enlarged view of part D in FIG. 4)

4 is a vertical cross-sectional side view of FIG.

5 is an enlarged view of part E in FIG.

[Explanation of symbols]

 1 ... Shield body 3 ... Tail plate 5 ... Segment 7 ... Ring-shaped body 9 ... Support plate 10 ... Gap 11A ... 1st sealing device 11B ... -Rubber 15 ... Third seal device 17 ... Leaf spring 19 ... Cavity 21 ... Tube 23 ... Recess

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[Procedure amendment]

[Submission date] March 10, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

[Title of Invention] Seal structure between shield and segment

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield structure for excavating in a shield construction method and a seal structure between a shield assembled into a ring-shaped body and a sliding segment in the shield.

[0002]

2. Description of the Related Art As is well known, the shield construction method is an excellent construction method for forming a tunnel or the like on soft ground. This method involves excavating the ground at the front while preventing the ground from collapsing with a shield made of a tubular iron plate. A tail plate made of a tubular iron plate is connected to the rear of the shield so as to be rotatable by a predetermined angle. By this rotation, the excavation direction of the tunnel can be changed. In this tail plate, segments made of reinforced concrete or the like, which have been divided and manufactured in a factory in advance, are joined to each other in an annular shape to form a ring-shaped body, and the ring-shaped body already assembled and connected to the ring-shaped body existing behind. Then, a jack is applied to this new joined ring-shaped body to advance the shield and tail plate. As a result, the ring-shaped bodies are connected in a cylindrical shape to support the ground of the tunnel.

When the tunnel is located deep below the water table, the tail plate and the tubular body are
Watertightness must be maintained through sliding movement through the sealing device.

In this sealing device for keeping watertightness, a rubber with a spring called a wire brush is provided all around the inner peripheral surface of the tail plate, and the rubber is brought into close contact with the outer periphery of the segment by a spring. A plurality of this wire brush was provided in the axial direction of the tail plate, and the gap between them was filled with grease to prevent water from entering the inside.

[0005]

In the conventional shield construction method, the outer shape of the ring-shaped body assembled by joining the segments is larger than the inner diameter of the tubular tail plate so that the sliding is possible. However, the sealing device was provided in the gap between the two. Since the ring-shaped body is placed directly on the bottom of the tail plate, the center of the ring-shaped body does not coincide with the center of the tail plate, and the center of the ring-shaped body is eccentric downward. There is. For this reason, the above-mentioned gap becomes larger toward the top and becomes zero at the bottom. Therefore, the spring of the wire brush remains bent strongly near the bottom and easily yields, so when building a long distance tunnel etc. by the shield method, the life of the spring will reach by the end of construction. , It becomes difficult to maintain watertightness under high water pressure.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a shield / segment seal structure which has a long life and can sufficiently maintain watertightness.

[0007]

In order to achieve the above object, the present invention provides a support plate having an arcuate cross section for supporting a ring-shaped body at the bottom of the tail plate, and the thickness of the support plate. By making the ring-shaped body and the tail plate substantially concentric with each other, the gap between the two is made substantially concentric around the entire circumference, and a sealing device for maintaining watertightness in this gap is provided all around.

As in the conventional case, the sealing device may be only one provided with a wire brush made of rubber with spring, or may be a device additionally provided with another type of sealing device. That is, a sealing device in which compressed air is enclosed in a rubber tube and closely adhered to the ring-shaped body and grease or compressed air is interposed in the gap between the tube and the ring-shaped body is provided side by side in the axial direction of the tail plate. May be

[0009]

By making the gap between the ring-shaped body and the tail plate substantially the same over the entire circumference, the spring of the sealing device provided in this gap can be properly bent over the entire circumference.

Further, since the gap can be kept substantially the same (constant) over the entire circumference, the sealing device is not limited to one provided with a rubber with a spring called a wire brush, and compressed air is enclosed in a rubber tube. It is also possible to install side dishes, which makes it easier to maintain water tightness. Further, by inserting grease or compressed air between the tube and the ring-shaped body, water tightness can be further ensured.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As in the overall schematic diagram shown in FIG. 4, the ground is excavated at the front of the tubular shield body 1 made of iron. At the rear of the shield body 1, there is a tubular tail plate 3 made of iron.
Are connected. Shield body 1 and tail plate 3
The hydraulic cylinder (not shown) can change the relative angle within a predetermined angle, thereby changing the direction of the tunnel to be excavated. Within the tail plate 3, the concrete segment 5 is joined into a ring shape as shown in FIG. The ring-shaped body 7 newly joined and assembled in this way is connected to the already joined rear ring-shaped body 7. After that, a shield jack (not shown) is applied to the newly joined ring-shaped body 7, and the shield body 1 and the tail plate 3 are advanced to the left in the figure.
The joining work, the assembling work, and the connecting work of the segments 5 are performed on the support plate 9 (FIG. 2) provided at the bottom of the tail plate 3. The support plate 9 has an arcuate cross section, and its thickness is such that the assembled ring-shaped body 7 and the tail plate 3 can be made substantially concentric (FIG. 1).

By making them concentric in this way, the gap 10 between the ring-shaped body 7 and the tail plate 3 becomes substantially the same on the entire circumference, and the sealing device 11 is provided on the entire circumference in this gap. The sealing device 11 includes two types of sealing devices 11A and 11A.
B is provided side by side in the axial direction of the tail plate 3. First
The sealing device 11A is provided with a plurality of spring rubbers called wire brushes 13 (three in FIG. 5) as in the conventional case. Each of the wire brushes 13 has a leaf spring 17 in which the rubber 15 at the tip is in close contact with the outer surface of the segment 5. The space between the wire brushes 13 is filled with grease to prevent water from entering the gap 10 from the outside.

A second sealing device 11B is provided in front of the first sealing device 11A. The second sealing device 11B is one in which compressed air is enclosed in a rubber tube 21 having two cavities 19 as shown in FIG. It is also possible that compressed air can be taken in and out. A recess 23 is formed in the center of the tube 21 in the front-rear direction.
Inject grease that has the function of preventing air and water leaks. Further, compressed air is injected between the tube 21 and the adjacent wire brush 13 to prevent water from entering.

As described above, according to this embodiment, by providing the support plate 9 between the bottom of the tail plate 3 and the ring-shaped body 7, the ring-shaped body 7 and the tail plate 3 are substantially concentric. Can be located. The gap 10 between the both 7 and 3 can be made substantially the same over the entire circumference. As a result, the mounting angle of the leaf spring 17 of the first rising seal device 11A can be made uniform and proper over the entire circumference, so that the leaf spring 17 is hard to yield and its life is extended. It is possible to increase the watertightness keeping function.

[0015] By the ring-shaped body 7 and the tail plate 3 substantially concentric, also rotates and the shield body 1 and the tail plate 3 with the excavation, the gap 10 is substantially the same <br/> state all around Can be maintained. Therefore, the second sealing device 1 using the tube 21 that is relatively weak against the change in the gap is used.
1B can also be sufficiently adopted, and the high water-tightness retaining function peculiar to the sealing device using the tube 21 can be exhibited.

Since the support plate 9 is provided on the tail plate 3, the total length of the tail plate 3 becomes longer than before, but this also brings about an advantage that the work time for joining the segments 5 and other work time in the tail plate can be lengthened.

The above Te is at the embodiment, it the second sealing device 11B is is provided with a tube 21 one step, the Oite to another embodiment also be provided two-stage, or three or more stages Is also possible.

In the above embodiment, the support plate 9
The radius of curvature of the arc-shaped cross-section of is not the same as the radius of curvature of the segment 5 and is slightly larger (FIG. 2) .

[0019]

As described above, according to the shield-segment sealing structure of the present invention, the gap between the ring-shaped body and the tail plate can be made substantially the same over the entire circumference, and the sealing device can be provided. It is possible to evenly and properly bend the constituent springs, extend the life of the springs, and enhance the watertightness retaining effect. Further, since the gap can be made substantially the same and constant over the entire circumference, the sealing device is not limited to a conventional wire brush made of rubber with a spring, and is made of a rubber having a higher watertight function and higher durability. It is possible to use a tube in which compressed air is enclosed, and it is possible to maintain higher watertightness by interposing grease or compressed air between the tube and the ring-shaped body.

[Brief description of drawings]

FIG. 1 is a horizontal cross-sectional front view (cross-sectional view taken along line AA of FIG. 4) of a tail plate portion of a shield excavator including a shield-segment sealing structure according to an embodiment of the present invention.

FIG. 2 is an enlarged view of part B in FIG. (B-B sectional view of FIG. 3)

FIG. 3 is a sectional view taken along line CC of FIG. (Enlarged view of part D in FIG. 4)

4 is a vertical cross-sectional side view of FIG.

5 is an enlarged view of part E in FIG.

[Explanation of symbols] 1 ... Shield main body 3 ... Tail plate 5 ... Segment 7 ... Ring-shaped body 9 ... Support plate 10 ... Gap 11A ... 1st Sealing device 11B ... Second sealing device 15 ... Rubber 17 ... Leaf spring 19 ... Cavity 21 ... Tube 23 ... Recess

Claims (2)

[Claims] 1. An excavation is performed at the front part of a tubular shield, and segments are joined in an annular shape in a rear tubular tail plate to form a ring-shaped body, which is connected to an already joined rear ring-shaped body, Then, in the tail plate of the shield construction method of advancing the shield and the table plate by applying a jack to the joined ring-shaped body, a support plate having an arcuate cross section for supporting the ring-shaped body is provided at the bottom of the tail plate, By making the ring-shaped body and the tail plate substantially concentric depending on the thickness of the support plate, the gap between the two is made substantially the same over the entire circumference, and a seal device for maintaining watertightness in the gap is provided between the shield segments. Seal structure 2. A sealing device is not only a sealing device in which rubber with a spring is provided in the axial direction of a plurality of tail plates and filled with grease between them, but compressed air is enclosed in a rubber tube to form a ring-shaped body. 2. The shield-segment sealing structure according to claim 1, further comprising a sealing device which is closely attached to the other gap between the tube and the ring-shaped member and in which grease or compressed air is interposed in the axial direction of the tail plate.