JP4960214B2 - Tunnel opening structure - Google Patents

Description

The present invention relates to a tunnel opening portion formed by widening a tunnel by connecting the tunnel and a casing.

Conventionally, the construction of the tunnel opening portion is performed by connecting the tunnel and the frame and removing the segment of the portion where the tunnel and the frame face. For this reason, a large cross-sectional force is required at the tunnel opening portion.

In general, a fireproof coating is applied to the inner peripheral surface of the tunnel. For this reason, it is desirable that the tunnel inner surface be as smooth as possible. Therefore, a synthetic segment or the like may be used in place of a conventionally used steel shell (steel-based segment). According to synthetic segments, etc., even if the height is lower than that of conventional steel-based segments, the strength is high and the inner surface is covered with a skin plate. Efficiency is good.

As a tunnel opening part considering such strength, for example, only the removal part segment removed at the time of widening is a steel segment, the other part is a synthetic segment, etc., and appropriate depending on the part of the tunnel In order to obtain a sufficient proof stress, there is a segment ring structure in which the thickness of the segment is changed (Patent Document 1).

In addition, there is a segment structure in which the digit height of a segment of a portion having a large bending moment generated in a joint portion of a segment constructing a tunnel is made smaller than that of other portions (Patent Document 2).
JP 2003-41900 A JP 2004-204545 A

However, since the segment ring structure described in Patent Document 1 uses a synthetic segment or the like for the connection between the internal structure and the segment, a special structure is required for the connection between the internal structure that is a concrete structure and the segment. There is a problem. Further, a large bonding strength is required in the vicinity of the connection portion between the segment and the internal structure, but there is a problem that no consideration is given to the bonding strength in the vicinity of the connection portion between the segment and the internal structure.

In addition, the segment structure described in Patent Document 2 does not consider the joint strength, and particularly in the vicinity of the connection portion between the segment and the internal structure, a high joint strength is required. Therefore, there is a problem that a special structure is required to obtain high bonding strength.

The present invention has been made in view of such problems, has a high cross-sectional force, does not require a special joint structure at the connection portion with the housing, and requires a high joint strength for joining the segments. An object of the present invention is to provide a tunnel slit structure having a large bonding strength.

In order to achieve the above-described object, the present invention provides a tunnel opening structure in which a tunnel and a casing adjacent to the tunnel are connected, and the tunnel is formed by a plurality of segments and faces the casing. The segment of the position is removed, and a steel-based segment is provided at the connection portion between the tunnel and the frame, and the steel-based segment is one of a steel-concrete composite segment, a reinforced concrete segment, and a concrete-filled steel segment. A second segment of any one of a steel-concrete composite segment, a reinforced concrete segment, and a concrete-filled steel segment is provided, except for the steel-based segment and the first segment. 1 segment with the steel-based segment The thickness of the joint portion is larger than the thickness of the joint portion with the second segment, and the joint portion with the steel-based segment of the first segment is a plate in the thickness direction of the first segment. A member is provided, a notch is provided in the plate member, an insert having a threaded portion is provided in the notch, and the steel-based segment and the first segment are joined by the insert and a bolt. It is a tunnel opening structure characterized by being made .

The plate member may be joined to inner and outer skin plates of the first segment, and the height of the plate member may be changed according to a change in the thickness of the first segment. In addition, the joint between the steel-based segment and the first segment has a joint strength that is greater than the joint between the first segment and the second segment and the joint between the second segments. May be large.

  The steel-based segment and the first segment may be provided in a staggered manner with respect to the axial direction of the tunnel.

According to the present invention, most of the segments constituting the tunnel are synthetic segments, etc., so that the cross-sectional force of the tunnel is large, and the inner surfaces of the synthetic segments, etc. are smooth, so that fireproof coating of the tunnel inner surface is easy. In addition, since the steel segment is provided at the connecting part with the housing, it is easy to join the housing and the segment, no special structure is required, and it is provided near the connecting part with the housing, which requires the greatest strength. It is possible to provide a tunnel opening structure having a large joint strength at the joint between the synthetic segment and the steel-based segment.

According to the present invention, a portion having a high joint strength, having a high cross-sectional force, does not require a special joint structure at the connection portion with the housing, and requires a high joint strength for joining the segments to each other. Structure can be provided.

Hereinafter, a tunnel opening structure 1 according to an embodiment of the present invention will be described. FIG. 1 is a diagram illustrating a tunnel opening structure 1 according to a first embodiment.

The tunnel opening structure 1 is provided so that the housing 3 is connected to the side of the shield tunnel 5. The housing 3 is composed of a lower bottom plate 4, a side wall 6, an upper bottom plate 8, and the like, and is a U-shaped structure made of reinforced concrete. The shape of the housing 3 may be a shape opened on both sides, such as joining two shield tunnels, in addition to the U-shape as shown in FIG. Other shapes of the housing 3 will be described later.

The shield tunnel 5 is composed of a plurality of segments. A connecting segment 9 between the shield tunnel 5 and the housing 3 (a portion where a part of the shield tunnel 5 is embedded in the housing 3) is provided with a steel segment 10 as a steel-based segment. That is, a part of the steel segment 10 is embedded in the upper bottom plate 8 and the lower bottom plate 4 respectively. Here, in addition to the steel segment, a ductile segment or the like can be used as the steel segment (in the following description, an example of the steel segment is shown). The synthetic segments 50 are joined to the steel segments 10 embedded in the upper bottom plate 8 and the lower bottom plate 4, respectively. A synthetic segment 30 is provided at a portion other than the steel segment 10 and the synthetic segment 50. Here, although the synthetic segment 30 and the synthetic segment 50 refer to a steel-concrete synthetic segment, a reinforced concrete segment, a concrete filling segment, or the like may be used instead of the steel-concrete synthetic segment (in the following description, steel An example of a concrete composite segment segment is shown). A fireproof coating (not shown) is applied to the inner surface of the shield tunnel 5.

A removal segment 7 is provided at a portion of the shield tunnel 5 facing the housing 3. The removal segment 7 is removed after the housing 3 is constructed. The removal segment 7 may be the steel segment 10 or the synthetic segments 30 and 50. However, the removal segment 7 can maintain the shield tunnel 5 until the housing 3 is constructed. In view of the ease of removal work, it is desirable to use a simple steel segment 10.

The thickness of each segment constituting the shield tunnel 5 (the digit height of each segment) varies depending on the type of segment. That is, the thickness of the composite segment 50 may be a thickness that can ensure the strength of the shield tunnel 5, but in the vicinity of the connection portion 9 with the housing 3, it receives a force from the surrounding earth and sand, High strength is required. In particular, since the joint portion between the segments is weak in strength, a large joint strength (strength for joining the segments) is required.

That is, the joint part of the steel segment 10 and the synthetic segment 50 located in the vicinity of the connection part 9 between the shield tunnel 5 and the housing 3 is required to have a greater joint strength. For this reason, in order to obtain higher joint strength, the thickness of the joint portion between the steel segment 10 and the synthetic segment 50 is different from the other portion (the portion other than the joint portion between the synthetic segment 50 and the steel segment 10, and It is desirable that the segment is thicker than the synthetic segment 30). The joint portion between the steel segment 10 and the synthetic segment 50 will be described later.

Next, details of the structure of each segment will be described. FIG. 2 is a perspective view showing the steel segment 10. The steel segment 10 is mainly composed of a skin plate 11, a side plate 13, a vertical rib 15, a joint plate 19, and the like. The skin plate 11 corresponding to the outer peripheral surface of the tunnel has a curved shape corresponding to the outer diameter of the tunnel. Side plates 13 are provided at both ends on the long side of the skin plate 11 toward the tunnel inward direction. Further, joint plates 19 are provided at both ends on the short side of the skin plate 11 in the same direction as the side plate 13. That is, the skin plate 11, the side plate 13, and the joint plate 19 form a box shape.

Vertical ribs 15 are provided at regular intervals in a direction substantially perpendicular to the side plate 13. The side plate 13 is provided with a joint hole 17 for joining other segments in the axial direction of the tunnel. The joint plate 19 is provided with a joint hole 21 for joining the segments in the circumferential direction. That is, the removal segment 7 is provided in one joint plate 19 of the steel segment 10, and the composite segment 50 is joined to the other joint plate 19. Each member is made of steel and joined by welding.

In order to connect the steel segment 10 and the housing 3, first, the skin plate 11 of the steel segment 10 is removed. By removing the skin plate 11, the steel segment 10 becomes a ladder shape, and the inside and outside of the shield tunnel 5 are spatially connected. Next, the vicinity of the center portion of the vertical rib 15 is cut. The cutting is for avoiding interference with a reinforcing bar or the like embedded in the housing 3. Further, if necessary, a shear connector or the like is joined and embedded in the housing 3. For this reason, the connection part 9 of the steel segment 10 and the housing 3 does not require a special structure, and the steel segment 10 and the housing 3 can be easily connected.

FIG. 3 is a perspective view showing the composite segment 30. The composite segment 30 mainly includes an outer skin plate 33, an inner skin plate 31, a side plate 35, a joint plate 37, and the like. The outer skin plate 33 and the inner skin plate 31 are provided to face each other, and a dowel (not shown) is provided inside the skin plate. The outer skin plate 33 and the inner skin plate 31 are joined together by a side plate 35 and a joint plate 37 to form a box shape. The outer skin plate 33 is a portion corresponding to the outer peripheral surface of the tunnel, and the inner skin plate 31 is a portion corresponding to the inner peripheral surface of the tunnel.

An injection hole 47 is provided in the side plate 35. The injection hole 47 is a hole for injecting concrete into the composite segment 30. That is, concrete 49 is placed in the composite segment 30 except for joint boxes 39 and 43 described later.

The side plate 35 is provided with a joint hole 41 for joining other segments in the axial direction of the tunnel. A joint box 39 is provided at a portion corresponding to the joint hole 41. The joint plate 37 is provided with a joint hole 45 for joining the segments in the circumferential direction. A joint box 43 is provided at a portion corresponding to the joint hole 45. The joint boxes 39 and 43 are box-shaped parts for connecting the segments in the joint holes 41 and 45.

The composite segment 30 or the composite segment 50 is joined to the joint plate 37 of the segment 30. Each member is made of steel and joined by welding.

4A and 4B are diagrams illustrating the composite segment 50, in which FIG. 4A is a perspective view and FIG. 4B is a cross-sectional view taken along line AA in FIG. 4A. The synthetic segment 50 has the same structure as the synthetic segment 30 except for the joint portion 51. Therefore, components having the same functions and structures as those of the synthetic segment 30 are assigned the same reference numerals as in FIG. 3 to avoid redundant description.

A joint plate 37 having a joint hole 45 is provided at one end of the composite segment 50, similarly to the composite segment 30. The composite segment 50 and the composite segment 30 are joined at the joint plate 37.

At the other end of the composite segment 50, a joint 51 is provided. The joint 51 is a joint with the steel segment 10. That is, in the shield tunnel 5, the joint portion 51 is located in the vicinity of the connection portion 9 between the housing 3 and the steel segment 10.

The joint portion 51 is thicker than other portions. A joint plate 52 is provided on the end face of the joint portion 51. An embedded anchor 55 is embedded in the joint plate 52. The embedded anchor 55 is provided with a screw 53 and joined to the steel segment 10 with a joining component such as a bolt.

By increasing the thickness of the joint portion 51, thicker bolts (embedded anchors 55) can be used, and the number of embedded anchors 55 can be increased. Further, since the joint portion 51 does not have a structure like a joint box, the interior is entirely filled with concrete 49. For this reason, the intensity | strength of joining part 51 itself can be raised, and joining strength with the segment 10 can be raised.

5 is an enlarged view of the vicinity of the joint 51, FIG. 5 (a) is a front view, and FIG. 5 (b) is a cross-sectional view of the vicinity of the joint 51. FIG. 5 shows the connecting portion 9 between the upper bottom plate 8 and the steel segment 10, but the connecting portion 9 between the lower bottom plate 4 and the steel segment 10 has the same structure. A description of the vicinity of the connecting portion 9 between the bottom plate 4 and the steel segment 10 is omitted.

As described above, the steel segment 10 is connected to the housing 3 by the connecting portion 9. At this time, the skin plate 11 of the steel segment 10 is removed. The joint 51 of the synthetic segment 50 and the steel segment 10 are joined by a steel segment joint 61. The other end of the composite segment 50 is joined to the composite segment 30 at the composite segment joint 63.

As shown in FIG. 5B, the joint plate 10 of the steel segment 10 and the joint plate 52 of the composite segment 50 are combined, and the bolt 65 penetrating the joint hole 21 is fixed to the screw 53. The steel segment 10 is joined.

The number of bolts 65 is not limited to the upper and lower two stages as shown in FIG. For example, three or more stages may be provided by increasing the thickness of the joint portion 51. Moreover, although all the steel segments 10 were made the same thickness, as above-mentioned, if the thickness of the steel segment junction part 65 vicinity is enough thick, you may make thickness of another part thinner. . That is, similarly to the synthetic segment 50, the segment thickness of the steel segment 10 may be changed.

FIG. 6 is a perspective view showing the appearance of the tunnel opening structure 1. The steel segment 10 a connected to the housing 3 is joined to the synthetic segment 50 a in the circumferential direction of the shield tunnel 5. The steel segment 10a is joined to the steel segment 10b in the axial direction of the shield tunnel 5, and the steel segments 10c and 10d are further joined. Similarly, the composite segment 50a is joined to the composite segment 50b in the axial direction of the shield tunnel 5, and the composite segments 50c and 50d are further joined.

As shown in FIG. 6, the steel segments 10 a, 10 b, 10 c, and 10 d are provided in a staggered manner in the axial direction of the shield tunnel 5. Therefore, the composite segments 50 a, 50 b, 50 c, 50 d are also provided in a staggered manner in the axial direction of the shield tunnel 5. That is, the steel segment joint portions 61a, 61b, 61c, and 61d, which are the joint portions of the steel segments 10a, 10b, 10c, and 10d and the synthetic segments 50a, 50b, 50c, and 50d, It does not line up in the axial direction but is staggered.

Thus, according to the tunnel slit structure 1 according to the present embodiment, a tunnel slit structure having a sufficiently high strength can be obtained. In particular, since the synthetic segment 30 or the synthetic segment 50 is provided up to the vicinity of the connection portion 9 between the housing 3 and the steel segment 10, it has sufficient strength and is easy to cover with fireproofing on the inner surface. For example, when fireproof coating is performed on the steel segment 10, it is necessary to cover only the thickness of the steel segment (for example, 40 cm), but the inner surface of the synthetic segment is smooth, so that the coating is about 3 cm, for example. Can cover the whole.

In addition, since the steel segment 10 is provided at the connection portion 9 between the housing 3 and the shield tunnel 5, the vertical ribs 15 (or separately provided shear connectors) of the steel segment 10 are embedded in the housing 3. The housing 3 can be reliably connected and does not require a special joint structure.

Moreover, since the thickness of the joint part 51 of the synthetic segment 50 is thick, the thickness of the joint part between the steel segment 10 and the synthetic segment 50 is high. Therefore, the size and number of the embedded anchors 55 can be increased. The joining strength between the steel segment 10 and the synthetic segment 50 can be increased. In particular, the joint portion 51 of the composite segment 50 does not have a joint box or the like, and the concrete 49 is filled inside, so that the strength of the joint portion 51 is high.

Further, the steel segment joints 61 are not arranged in a straight line in the axial direction of the shield tunnel 5 but are staggered. Do not concentrate on the place. For this reason, a stronger tunnel opening structure can be obtained.

Next, the synthesis segment 70 according to the second embodiment will be described. 7A and 7B are views showing the composite segment 70, in which FIG. 7A is a perspective view, FIG. 7B is a view showing the plate member 71, and FIG. 7C is BB in FIG. 7A. It is sectional drawing. In the following embodiment, components having the same functions as those of the synthetic segment 50 shown in FIG. 4 are assigned the same reference numerals as in FIG. 4 to avoid redundant description.

The synthetic segment 70 has substantially the same structure as the synthetic segment 50, but the structure of the joint portion 51 is different. That is, the composite segment 70 is provided with the plate member 71 inside the joint portion 51. The plate member 71 is provided between the outer skin plate 33 and the inner skin plate 31 substantially perpendicular to the joint plate 52. The plate-like member 71, the inner skin plate 31, and the outer skin plate 33 are joined by welding or the like. The plate-like member 71 is provided with a notch 75. The notch 71 is provided with a rod-like insert 73 having a screw 53. The plate-like member 71 and the insert 73 are joined by welding or the like.

According to the synthetic segment 70 concerning 2nd Embodiment, the effect similar to the synthetic segment 50 can be acquired. Further, since the insert 73 is welded to the plate member 71, the insert 73 does not come out of the synthetic segment 70 with respect to the tensile force in the axial direction of the insert 73. Further, since the plate member 71 is directly joined to the inner skin plate 31 and the outer skin plate 33, the stress transmitted to the insert 73 by joining with other segments is directly transmitted to the skin plate without passing through the concrete 49. Is done. For this reason, higher joint strength can be obtained. As described above, the synthetic segment 70 is a steel-concrete synthetic segment, but may be a concrete filling segment.

As mentioned above, although embodiment of this invention was described referring an accompanying drawing, the technical scope of this invention is not influenced by embodiment mentioned above. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

For example, the housing 3 is not limited to the shape shown in FIG. FIG. 8 is a view showing an embodiment having a shape different from that of the housing 3. As shown in FIG. 8 (a), when the space between the two shield tunnels 5a and 5b is widened, it can be shaped like an opening on both sides as in the case 3a. Moreover, as shown in FIG.8 (b), it can also be set as the C-shaped housing | casing 3b which partially expands the shield tunnel 5. As shown in FIG. Furthermore, it can also be set as the window shape to the opening part provided in the shield tunnel 5. FIG. In any case, steel-based segments may be used for the joints between the casings 3a, 3b, and 3c and the shield tunnel 5, and synthetic segments or the like may be used for other portions.

Further, the cross-sectional shape of the shield tunnel 5 is not limited to a circular shape. For example, a flat shield tunnel shape such as an elliptical shape as shown in FIG. 9A may be used, and a shield that has a substantially rectangular shape as shown in FIG. 9B. It may be a tunnel shape. The present invention can be applied to shield tunnels of any shape.

In the present invention, the joining method and the thickness of the segment were changed in order to obtain the joining strength of the joint portion between the steel segment 10 and the synthetic segment 50, which is considered to require the most strength, but the joining strength is sufficient. If so, the thickness of the joint portion between the steel segment 10 and the synthetic segment 50 may be the same as that of other portions. In this case, the shield tunnel 5 has substantially the same thickness over the entire circumference. Moreover, the connection method of the steel segment 10 and the synthetic | combination segment 50 can also be set as the structure same as the general joint box 43 instead of the structure like the junction part 51, as long as joining strength is enough. That is, in some cases, the shield tunnel 5 can be configured by only the composite segment 30 and the steel segment 10 without using the composite segment 50 (70). A steel segment 1 (steel-based segment) may be used at the connection portion between the housing 3 and the shield tunnel 5, and a synthetic segment or the like may be used at other portions.

The figure which shows the tunnel opening structure 1. FIG. The perspective view which shows the steel segments 10. FIG. FIG. It is a figure which shows the synthetic | combination segment 50, (a) is a perspective view, (b) is AA sectional drawing of (a). It is a figure which shows the steel segment junction part 61 vicinity. (A) is a front view, (b) is sectional drawing of the junction part 51. FIG. The perspective view of the tunnel slit structure 1 which shows the state by which the steel segment junction parts 61 were provided in the zigzag form. It is a figure which shows the synthetic | combination segment 70, (a) is a perspective view, (b) is a perspective view of the plate-shaped member 71, (c) is BB sectional drawing of (a). It is a figure which shows the shape of the housing 3, (a) is a figure which shows the housing 3a, (b) is a figure which shows the housing 3b, (c) is a figure which shows the housing 3c, (d) is a perspective view of the housing 3c. It is a figure which shows the shape of the shield tunnel 5, (a) is a figure which shows the shield tunnel 5a, (b) is a figure which shows the shield tunnel 5b.

Explanation of symbols

1 ......... Tunnel opening structure 3 ......... Housing 4 ......... Lower bottom plate 5 ......... Shield tunnel 6 ......... Side wall 7 ......... Removal segment 8 ......... Upper bottom plate 9 ......... Connection 10 ... Steel segment 11 ... Skin plate 13 Side wall 15 ... Vertical rib 17 ... Joint hole 19 ... Joint plate 21 ... Joint hole 30 ... Synthetic segment 31 ... Inner skin plate 33 ... Outer skin plate 35 ... Side plate 37 ... Joint plate 39 ... Joint box 41 ... Joint hole 43 ... Joint box 45 ... Joint hole 49 ... Concrete 50 ......... Synthetic segment 51 ......... Joint portion 52 ......... Joint plate 53 ......... Screw 55 ......... Embedded anchor 57 ......... Givel 61 ... …… Sheet segment joint portion 63 ... …… Synthetic segment joint Part 65 ... Bolt 70 ... Segment 71 ......... plate member 73 ......... insert 75 ......... notch

Claims (4)

A tunnel opening structure in which a tunnel and a housing adjacent to the tunnel are connected,
The tunnel is formed by a plurality of segments;
The segment facing the housing has been removed,
In the connection portion between the tunnel and the housing, a steel segment is provided,
Wherein the steel-based segments, the steel-concrete composite segment, the first segment of one of the segments made of reinforced concrete segments and the concrete filled steel is joined,
Other than the steel-based segment and the first segment, a second segment of either a steel-concrete composite segment, a reinforced concrete segment, or a concrete-filled steel segment is provided,
In the first segment, the thickness of the joint with the steel segment is thicker than the thickness of the joint with the second segment,
A plate member is provided in the thickness direction of the first segment at a joint portion between the first segment and the steel-based segment, the plate member is provided with a notch portion, and the notch portion is provided with the notch portion. An insert having a threaded portion, and the steel-based segment and the first segment are joined to each other by the insert and a bolt . The plate member is joined to the inner and outer skin plate of the first segment, and the height of the plate member changes according to the change in the thickness of the first segment. The tunnel opening structure according to claim 1. The joint between the steel segment and the first segment is:
3. The tunnel cutting according to claim 1, wherein a bonding strength is higher than a bonding portion between the first segment and the second segment and a bonding portion between the second segments. Open structure. The steel segment and the first segment are:
Tunnel incision-out structure as claimed in any one of claims 3, characterized in that the axial direction of the tunnel, are provided in a staggered manner.

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