JP2005002619A - Flexible segment and joint structure of shield tunnel using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structurally simplified flexible segment for work execution of a shield tunnel, and a joint structure of the shield tunnel using the flexible segment, which can reduce costs required for the work execution of the shield tunnel. <P>SOLUTION: In this flexible segment 10, a pair of annular bodies is arranged in the state of facing each other at a prescribed interval; a cut-off member 15 with flexibility is laid between the pair of annular bodies; the annular body is equipped with a steel main beam 11 and a steel skin plate 12 which is continuously provided on the outer-peripheral-surface side of the main beam 11; a thickness t of a steel plate of the skin plate 12 is set at 16 mm or more; and the cut-off material 15 is directly fixed onto the skin plate 12. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flexible segment for constructing a shield tunnel having a simple structure and a joint structure for a shield tunnel using the same.
[0002]
[Prior art]
The shield tunnel 70 is formed by excavating the ground with a shield (digging machine) 72, and then assembling a covering material called a segment 71a into a ring shape, and connecting the segment ring 71 thus obtained in the direction of excavation of the shield 72. Formed (see FIG. 6). In order to stop the water between the segment rings 71 of the shield tunnel 70, a method of compressing with the sealing material 74 interposed (see FIG. 6 and FIG. 7) and a flexible segment (flexible segment) are arranged. How to do is known. In addition, in FIG. 7, the code | symbol 74a shows the groove | channel provided in the segment 71a in order to install the sealing material 74. FIG. In FIG. 6, FIG. 7 and other drawings, the symbol x indicates the axial direction of the shield tunnel, and the symbol y indicates the circumferential direction of the shield tunnel.
[0003]
However, in the former method using the sealing material 74, since the connecting portion of the segment ring 71 becomes rigid, it is convenient to receive the thrust from the shield jack 73, but if the ground is displaced, it cannot follow this. May cause water leakage.
On the other hand, according to the latter method using the flexible segment, flexibility is imparted to the joint structure of the shield tunnel, so that it is possible to cope with the displacement of the ground. In the joint structure using the flexible segment 75, as shown in FIG. 8, an adhesive member 76 formed by integrating an annular main frame 76a, a cylindrical collar support member 76b, and a cylindrical collar 76c is provided. And a fixed waterproof rubber 77 stretched between the pair of collars 76c or between the collar support members 76b. Patent Document 1). In this joint structure, a pair of frames 78 as thrust receiving members are installed between the pair of segment rings 71, and jack thrust is received by the pair of frames 78 and wedge members 78a when the shield tunnel is dug. After the thrust is no longer applied, the wedge material 78a is removed to give the joint structure flexibility.
[0004]
However, the joint structure shown in FIG. 8 has a problem that the strength of the attachment member 76 is not sufficient, so that it cannot sufficiently resist the water pressure from the natural ground side. Furthermore, since the joint surface is made of the collar 76c having a small thickness, there is almost no width for attaching the sealing material for primary water stop, and therefore there is a possibility of causing water leakage.
As another example of a joint structure using a flexible segment, an annular body 80 as shown in FIG. 9 is installed between a pair of segment rings (not shown) at a predetermined interval and facing each other. (See Patent Documents 2 to 5). The annular body 80 includes a main girder (outer plate) 81 and an inner main girder (inner plate) 82 that extend in the circumferential direction y, a skin plate (outer circumferential plate) 83 that forms the outer circumferential surface of the annular body 80, A vertical rib 84 is provided between the inner main girder 82 and disposed at a predetermined interval in the circumferential direction y (see FIG. 10), and a water stop member is disposed between the annular bodies 81 facing each other. Yes. Further, in the annular body 81 shown in FIG. 9, a primary water stop rubber 85 as a water stop member is disposed between the opposing skin plates 83, and a secondary water stop rubber 86 that can be expanded and contracted in the axial direction x is formed inside thereof. Further, a thrust receiving member 87 is disposed on the inside thereof. FIG. 10 shows one of the divided pieces 88 divided in the circumferential direction of the annular body 80 forming the flexible segment. The annular body 80 is formed by connecting the end face plates 89 of the split pieces 88 to each other with bolts.
[0005]
In the annular body 80, the inner main girder 82 and the vertical rib 84 are provided for the purpose of imparting a strength that can sufficiently resist the water pressure from the natural ground side, and transmitting the jack thrust during the shield excavation to adjacent segments. And are arranged. However, since a large number of the inner main girders 82 and vertical ribs 84 must be arranged, there is a problem that costs are increased.
[0006]
[Patent Document 1]
Japanese Utility Model Publication No. 62-27594 (FIGS. 2 and 7)
[Patent Document 2]
Japanese Patent No. 3283080 (FIGS. 1, 3 and 5)
[Patent Document 3]
Japanese Patent Publication No. 55-4919 (FIGS. 3 and 5)
[Patent Document 4]
Japanese Patent Publication No. 22-22818 (Figs. 2 and 6)
[Patent Document 5]
Japanese Patent No. 2733825 (FIGS. 2, 7, and 11)
[0007]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to provide a flexible segment for shield tunnel construction with a simplified structure, and a shield tunnel joint structure using the flexible segment, which can achieve a reduction in cost required for construction of the shield tunnel. Is to provide.
[0008]
[Means for Solving the Problems and Effects of the Invention]
In order to solve the above problems, a flexible segment according to the present invention is arranged in a state where a pair of annular bodies are opposed to each other with a predetermined distance therebetween, and a water-stopping member having flexibility is hung between the pair of annular bodies. The annular body includes a steel main girder and a steel skin plate continuously provided on the outer peripheral surface side of the main girder, and the thickness of the steel plate of the skin plate is 16 mm or more. And the water stop member is directly fixed on the skin plate.
[0009]
Further, the joint structure of the shield tunnel according to the present invention for solving the above-mentioned problem is formed by arranging a flexible segment between the side end surfaces of a pair of segment rings, and the flexible segment is made of steel. And a pair of annular bodies provided with a steel skin plate continuously provided on the outer peripheral surface side of the main girder, and a flexible water stop member spanned between the pair of annular bodies. The thickness of the steel plate of the skin plate is 16 mm or more, and the water stop member is directly fixed on the skin plate.
[0010]
As shown in FIGS. 9 and 10, the conventional flexible segment is formed by welding an iron plate 90 for attaching a water stop member to an inner main girder 82 or the like in a box-shaped frame (divided piece 88). A water stop member is attached to the iron plate 90 or a water stop member is attached directly to the inner main girder 82. Therefore, as described above, the inner main girder is necessary for the structure, and the vertical rib 84 is also necessary for maintaining the strength of the divided piece 88 itself.
[0011]
In contrast, in the present invention, a steel plate having a thickness of about 3 mm to 6 mm is usually used as the skin plate of the flexible segment, and a steel plate having a thickness of 16 mm or more is used. Thereby, (1) It becomes possible to arrange | position the sealing material for primary waterproofing of sufficient thickness between right-and-left skin plates. A flexible water-stopping member that is stretched between a pair of annular members of a flexible segment usually has a thrust receiving member disposed between the annular members removed after jack thrust is not applied. It is attached from. Therefore, in order to prevent water leakage until the water stop member is attached, a sealing material for primary water stop is required. The primary water-stop sealing material needs to have a thickness of at least 16 mm, although it depends on the size of the acting water pressure and the material of the sealing material. According to the present invention, as described above, the steel plate used as the skin plate Since the thickness is 16 mm or more, it is possible to attach a sealing material for primary water stop having at least a thickness of 16 mm.
[0012]
In addition, according to the present invention, since the thickness of the steel plate for skin plate is 16 mm or more, (2) the water stop having flexibility as a secondary water stop or a temporary water stop material directly on the skin plate. A member can be attached. Usually, such a water-stopping member is constructed by laying a flexible rubber plate between a pair of annular bodies and fixed with bolts, and is different from a primary water-stop sealing material. Note that the water-stopping member having the flexibility described above is being used for the primary water-stopping member instead of the conventional sealing material that simply fills the space between the left and right frames. When trying to fix such a flexible rubber member with a bolt, for the purpose of securing an effective depth of the bolt, a thickness of at least 16 mm or more is required at its mounting position. ) Is 16 mm or more, it is possible to directly attach a water-stopping member having flexibility for secondary water-stopping or temporary water-stopping with a bolt on the skin plate.
[0013]
Furthermore, according to the present invention, since the thickness of the steel plate for skin plate is 16 mm or more, the strength thereof is remarkably increased as compared with the conventional one (thickness of about 3 to 6 mm). Even if a plate material (joint plate) extending in the axial direction of the shield tunnel is provided only at the connecting portion of the split pieces constituting the ring of the flexible segment, sufficient strength as the flexible segment can be obtained. it can. Therefore, the inner main girder and the vertical rib are not required.
[0014]
Therefore, according to the flexible segment of the present invention and the joint structure of a shield tunnel using the same, the structure can be simplified while maintaining the strength of the flexible joint in the shield tunnel, and the joint structure is formed. The cost required to do so can be greatly reduced.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Next, a flexible segment according to the present invention and a joint structure of a shield tunnel using the flexible segment will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of a flexible segment according to the present invention. A flexible segment 10 according to the present invention is arranged in a state where a pair of annular bodies composed of a main girder 11 and a skin plate (outer peripheral plate) 12 are opposed to each other with a predetermined distance therebetween, and a pair of skins in the pair of annular bodies. A primary water stop member 14 is provided between the plates 12, and a secondary water stop rubber 15 having flexibility is stretched between the pair of skin plates 12.
[0016]
The main girder 11 is a steel arcuate plate member designed according to the cross-sectional shape of the segment 71a forming the segment ring, and is attached to the main girder 71b (end surface of the segment ring) of the segment 71a. And is fixed by an inter-ring bolt 16. In the flexible segment 10 shown in FIG. 1, the packing 17 for preventing water leakage is provided between the main beam 11 of the flexible segment 10 and the segment 71a. A cover plate 18 is provided on the outer peripheral surface of the skin plate 12 mainly in the vicinity of the primary water stop member 14.
[0017]
The skin plate 12 is a portion that forms the outer peripheral surface of the flexible segment 10, and is a steel member that is connected to the main girder 11. In the flexible segment 10 according to the present invention, the thickness t of the skin plate 12 is set to be 16 mm or more. When the thickness t of the skin plate 12 is less than 16 mm, it becomes impossible to dispose the primary water stop member 14 between the left and right skin plates 12, and sufficient strength is given to the flexible joint portion in the shield tunnel. Can not be. The thickness t of the skin plate 12 is particularly preferably 22 mm or more, and more preferably 32 mm or more, in the above range.
[0018]
The flexible segment 10 is arranged between a pair of segment rings as an annular body 20 as shown in FIG. The annular body 20 is formed by connecting divided pieces 21 divided into a plurality in the circumferential direction y of the shield tunnel with their joint plates (end plate) 13 and fixing them with bolts 19 between the divided pieces. Assembled into. 2 is a view (side cross-sectional view) of the flexible segment shown in FIG. 1 as viewed in the direction of arrows AA, and FIG. 1 is a cross-sectional view taken along line BB in FIG.
[0019]
As shown in FIG. 3, the split piece 21 of the flexible segment 10 has an arc shape including a main beam 11, a skin plate 12, and a joint plate 13, and is a pair of substantially box-shaped members. In FIG. 3, reference numeral 19 a indicates a bolt hole for the split-piece bolt 19. In addition, in the division | segmentation piece 21 shown in FIG. 3, the primary waterproofing member 14, the secondary waterproofing rubber 15, its fixing means, etc. are abbreviate | omitted.
FIG. 4 is a longitudinal sectional view of a connecting portion of the flexible segment 10 (divided piece 21) according to the present invention, that is, a sectional view taken along the line CC in FIG. In the flexible segment 10 shown in FIG. 4, the packing 17 is disposed over the end surface of the skin plate 12 in order to further ensure the water stop at the connecting portion of the divided pieces 21.
[0020]
The primary water stop member 14 is a member made of, for example, urethane resin, epoxy resin, or the like, and can be deformed to some extent corresponding to the displacement of the ground while exhibiting a water stop action between the pair of skin plates 12. is there.
The secondary water stop rubber 15 is a water stop member having flexibility, and is made of, for example, rubber and can be deformed corresponding to a large displacement of the ground. The flexible segment 10 according to the present invention is characterized in that the secondary waterproof rubber 15 is directly fixed to the skin plate 12. In the case of the flexible segment 10 shown in FIG. 1, a holding plate 22, bolts 23, and spacers 24 and 25 are used as the fixing means for the secondary water stop rubber 15.
[0021]
When the jacking thrust is applied to the flexible segment 10 of the present invention, for example, as shown in FIG. 5A, the thrust receiving force is received between the main girders 11 in the pair of annular bodies at the stage before the secondary waterproof rubber 15 is attached. Materials 26a-26c are arranged. FIG. 5 (b) is a view (side sectional view) of the annular body 20 of the flexible segment 10 shown in FIG. 5 (a) as seen in the direction of the arrow DD, and FIG. It is EE sectional drawing of (b).
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an embodiment of a flexible segment according to the present invention and a joint structure of a shield tunnel using the same.
FIG. 2 is a partially cutaway side view showing an example of a ring formed by assembling divided pieces 20 of a flexible segment 10;
FIG. 3 is a partially broken perspective view showing a divided piece of the flexible segment 10 shown in FIG. 1;
4 is a longitudinal sectional view of a connecting portion of a flexible segment 10 shown in FIG.
5A is a longitudinal sectional view showing a state in which the thrust receiving member 26 is installed on the flexible segment 10 shown in FIG. 1, and FIG. 5B is a view taken along the line DD in FIG. is there.
FIG. 6 is a longitudinal sectional view schematically showing a shield tunnel.
FIG. 7 is a partially broken perspective view showing an example of a conventional water stop structure of a shield tunnel.
FIG. 8 is a longitudinal sectional view showing an example of a conventional joint structure using a flexible segment.
FIG. 9 is a longitudinal sectional view showing another example of a conventional joint structure using a flexible segment.
10 is a partially broken perspective view showing a divided piece of the annular body 80 shown in FIG. 9. FIG.
[Explanation of symbols]
10 Flexible Segment 11 Main Girder 12 Skin Plate 15 Secondary Waterproof Rubber (Flexible Waterproof Rubber)
20 Ring

Claims (2)

A pair of annular bodies arranged in a state of being opposed to each other with a predetermined spacing, and a flexible segment formed by bridging a water-stopping member having flexibility between the pair of annular bodies,
The annular body includes a steel main girder and a steel skin plate continuously provided on the outer peripheral surface side of the main girder,
A flexible segment, wherein the thickness of the steel plate of the skin plate is 16 mm or more, and the water stop member is directly fixed on the skin plate. A shield tunnel joint structure in which a flexible segment is disposed between side end surfaces of a pair of segment rings,
The flexible segment includes a pair of annular bodies each including a steel main girder and a steel skin plate continuously provided on the outer peripheral surface side of the main girder, and the flexibility spanned between the pair of annular bodies. A substantially cylindrical water stop member having
A shield tunnel joint structure, wherein a thickness of a steel plate of the skin plate is 16 mm or more, and the water blocking member is directly fixed on the skin plate.

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