JP2015175164A - Flexible segment for shielding method and construction method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible segment for a shielding method having a simple structure which can respond even to large reduction deformation and a construction method of the same.SOLUTION: A flexible segment 1 for a shielding method includes: a pair of frame segments 2 that includes a frame segment 2a including a frame skin plate 10 and a circular arc-shaped inner main girder 7a and outer main girder 8 opposed and erected at both ends of the frame skin plate 10 in a tunnel axial direction A, with the outer main girder 8 having a wider width in a tunnel radial direction R than the inner main girder 7a, and a frame segment 2b having the same structure as the frame segment 2a, in such a way that the inner main girders 7a and 7b are opposed to each other at intervals in the axial direction A; a cut-off rubber 3 interposed between the inner main girders 7a and 7b; an inner segment 4 including an inner skin plate 12 and two or more circular arc-shaped main girders 13a and 13b opposed and erected at both ends of the inner skin plate 12 in the axial direction A, with the inner segment 4 attached to the inner peripheral side of the pair of frame segments 2; and thrust receiving members 5a and 5b detachably installed between the outer main girder 8 and the main girders 13a and 13b.

Description

  The present invention relates to a flexible segment used in a shield method and a construction method thereof, and more particularly to a flexible segment capable of absorbing displacement due to an earthquake and the like and a construction method thereof.

  A tunnel constructed by the shield method is provided with a flexible portion that absorbs the displacement of the tunnel in order to prevent damage due to earthquakes, temperature changes, uneven settlement of the ground, and the like. As such a flexible portion, a flexible segment in which a stretchable water stop rubber is interposed between a pair of annular bodies arranged side by side may be used. For example, in Patent Document 1, a waterproof rubber that can be expanded and contracted in the axial direction is stretched between a pair of annular bodies that are spaced apart from each other and face each other. A flexible segment is described that is provided with a backup material that prevents excessive deformation of the rubber inward. Further, it is described that the backup material includes a support member (temporary thrust receiving material) that is temporarily installed between a pair of annular bodies so as to be freely movable.

  In recent years, it has been required to conduct seismic safety checks on underground structures. And according to the result of the earthquake resistance calculation (level 2 ground motion) performed for the underground shield tunnel, it may be necessary to install a flexible segment capable of handling a large displacement.

JP-A-6-180096

  Furthermore, depending on the selection of seismic waves, there may be obtained a seismic calculation result that the contraction displacement is larger than the extension displacement, and a flexible segment that can cope with a contraction displacement that is about ten times as large as the extension displacement is required. It is done. However, since the flexible segment described in Patent Document 1 has a structure in which the amount of expansion / contraction displacement is determined by the separation width of the pair of nuts constituting the temporary thrust receiving member, such a large contraction displacement is necessary. There is a problem that it is not possible to cope with it. In addition, since the backup material is composed of a plurality of arc-shaped members and a temporary thrust receiving material that supports them, there is a problem that the structure becomes complicated.

  An object of the present invention is to provide a flexible segment for a shield construction method having a simple structure capable of dealing with a large shrinkage displacement and a construction method thereof in order to solve the above-described problems of the prior art.

The flexible segment for shield construction of the present invention that achieves the above object includes the following aspects.
(1) a curved plate-like frame skin plate that forms an outer peripheral surface, and arc-shaped inner main girder and outer main girder that are erected in the center direction at both ends in the tunnel axis direction of the frame skin plate; A pair of frame segments in which the outer main girder is a frame segment having a wider width in the radial direction of the tunnel than the inner main girder, and the inner main girder faces each other with a gap in the axial direction.
A waterproof rubber interposed between the inner main beams of the pair of frame segments and capable of expanding and contracting in the axial direction;
A curved plate-like inner skin plate whose curvature is larger than the inner circumference of the inner main girder, and two or more arc-shaped main girders that are erected in the center direction at at least both ends in the axial direction of the inner skin plate An inner segment that is attached to the inner peripheral side of the pair of frame segments to suppress deformation to the inside of the waterproof rubber, and
A thrust receiving member detachably installed between the outer main girder of the pair of frame segments and the main girder of the inner segment;
By removing the thrust receiving material, the outer main girder of the pair of frame segments can move in the axial direction by the same distance as the axial width of the thrust receiving material, and the axial displacement Can absorb,
Flexible segment for shield method.
(2) The inner segment is divided into a plurality of segment pieces in the axial direction.
The flexible segment for a shield construction method according to the above (1).
(3) The inner segment has an extension control member that controls extension of the water stop rubber in the axial direction on the inner skin plate.
The flexible segment for shield method according to the above (1) or (2).
(4) The thrust receiving material is removed from the flexible segment for shield method according to any one of (1) to (3), and the outer main girder of the pair of frame segments and the inner segment A flexible segment for a shield method, which is provided with a joint member that closes the space between the main girders and prevents the lining material from flowing in during secondary lining.
(5) A plurality of flexible segments for shield method according to any one of (1) to (3) are joined in the circumferential direction of the tunnel to form a frame segment ring and an inner segment ring,
When the thrust is no longer affected, the thrust receiving material is removed;
Construction method of flexible segment for shield method.

  ADVANTAGE OF THE INVENTION According to this invention, the flexible segment for shield methods of a simple structure which can absorb a big shrinkage displacement, and its construction method are provided.

It is a partial notch perspective view which shows the schematic structure of the shield tunnel using the flexible segment which concerns on one Embodiment of this invention. It is a tunnel axial direction sectional view at the time of tunnel excavation of a flexible segment concerning one embodiment of the present invention. It is tunnel axial direction sectional drawing at the time of completion of the tunnel of the flexible segment which concerns on one Embodiment of this invention. It is tunnel axial direction sectional drawing at the time of completion of the tunnel of the flexible segment which concerns on one Embodiment of this invention. It is tunnel axial direction sectional drawing which shows the state which the water stop rubber of the flexible segment which concerns on one Embodiment of this invention shrunk | reduced, and the outer main girder of the frame segment moved to the tunnel axial direction. It is a fragmentary perspective view which shows the state which installed the thrust receiving material of the flexible segment which concerns on one Embodiment of this invention. It is the top view (a) and front view (b) which show the frame segment of the flexible segment which concerns on one Embodiment of this invention. It is the top view (a) and front view (b) which show the inner segment of the flexible segment which concerns on one Embodiment of this invention. It is an assembly drawing of the frame segment of the flexible segment which concerns on one Embodiment of this invention. It is an assembly drawing of the inner segment of the flexible segment which concerns on one Embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings, but the scope of the present invention is not limited thereto. In addition, terms such as the axial direction A, the circumferential direction C, and the radial direction R shown in FIG.

  FIG. 1 is a partially cutaway perspective view showing a schematic structure of a shield tunnel using a flexible segment for a shield method according to the present invention. A flexible segment ring in which the flexible segments 101 to 105 are joined is installed between standard segments T1 and T2 made of reinforced concrete or the like. The flexible segment for a shield method according to the present invention is a segment that constructs a support work by lining a tunnel inner wall in a tunnel constructed by such a shield method.

  FIG. 2 is a tunnel axial direction sectional view showing the structure of the flexible segment 1 for shield method according to the present invention during tunneling (the frame segment is a vertical rib portion, and the inner segment is a joint portion). The flexible segment 1 includes a pair of arc-shaped frame segments 2a and 2b arranged to face each other at a predetermined interval in the tunnel axis direction A, and a tunnel axis direction A interposed between the frame segments 2a and 2b. The water-stopping rubber 3 that can be expanded and contracted, the inner segment 4 attached to the inner peripheral side of the pair of frame segments 2a and 2b, and the frame segments 2a and 2b at both ends in the tunnel axis direction A of the inner segment 4 respectively. And thrust receiving members 5a and 5b interposed in a detachable manner. Moreover, it has the cover plate 6 which covers the outer peripheral side between a pair of frame segments 2a and 2b.

  FIG. 7A is a view of the frame segment as viewed from the radial center side. The upper and lower sides of the drawing are the tunnel axis direction A and the left and right sides are the tunnel circumferential direction C. FIG. As shown in FIG. 7A, the frame segment 2a has two main girders 7a, 8 and two joint plates 9a, 9c and a frame skin plate 10 (see FIGS. 2 and 7). The main girders 7a and 8, joint plates 9a and 9c, and the frame skin plate 10 are all plate-like members made of steel or the like. FIG. 7B is a view of FIG. 7A as viewed from above in the drawing, and is a front view as viewed from the tunnel axis direction A. FIG. As shown in FIG. 7 (b), the two main girders 7a and 8 have a shape extending in an arc shape in the tunnel circumferential direction C, and both end portions of the curved plate-like frame skin plate 10 in the tunnel axial direction A. And the width in the tunnel radial direction R is different. The frame skin plate 10 forms the outer peripheral surface of the flexible segment for shield method of the present embodiment. Of the two main girders 7a and 8, the narrower one in the tunnel radial direction R is the inner main girder 7a and the wider one is the outer main girder 8. Here, the end of the frame skin plate 10 on which the inner main girder 7a is erected may not be the tip, and the frame skin plate 10 may be further extended in a tab shape from the portion where the inner main girder 7a is erected. it can. The two joint plates 9a and 9c have the same width in the tunnel radial direction R as the inner main girder 7a, and are disposed at both ends of the two main girders 7a and 8 in the tunnel circumferential direction C.

  As shown in FIGS. 2 and 7, the pair of frame segments 2 includes a frame segment 2 a and 2 b having the same structure as the frame segment 2 a with a predetermined interval in the tunnel axis direction A. Are arranged so as to face each other. The size of the frame segment 2 can be appropriately changed depending on the transportability, assemblability, and the like (see 201 to 205 in FIG. 9). Further, for example, in FIG. 9, the installation angle of the joint plate 9 with respect to the frame skin plate 10 and the circumferential end shape of the outer main girder 8 are appropriately changed so that the frame segment 201 can be finally inserted when the frame segment is assembled. It is also possible to do.

  The water-stopping rubber 3 is a member that prevents inflow of water from outside the tunnel and imparts flexibility to the flexible segment 1, and is a plate-like rubber member having a corrugated cross section in the tunnel axial direction (see FIG. 2). . An end portion of the waterproofing rubber 3 in the tunnel axial direction A is fixed to the inner main girder 7 of the frame segment 2 by a waterproofing rubber mounting bolt 11.

  As shown in FIG. 2, a cover plate 6 can be installed between the frame segments 2 a and 2 b so as to be in close contact with the frame skin plate 10. The cover plate 6 is a plate-like member made of steel or the like that prevents entry into a waterproof rubber portion such as earth and sand that prevents deformation of the waterproof rubber during a disaster.

  FIG. 8A is a view of the inner segment as viewed from the radial center side. The upper and lower sides of the page are the tunnel axis direction A and the left and right sides are the tunnel circumferential direction C. FIG. FIG. 8B is a view of FIG. 8A as viewed from the top of the page, and is a front view as viewed from the tunnel axis direction A. FIG. As shown in FIGS. 8A and 8B, the inner segment 4 includes an inner skin plate 12 that is a rectangular plate made of curved plate-like steel, and the tunnel axis direction A of the inner skin plate 12. Two main beams 13a and 13b made of steel or the like standing upright in the center direction at both ends, and steel or the like standing upright in the center direction at both ends in the tunnel circumferential direction C of the inner skin plate 12 Two joint plates 14a and 14c are provided (see FIGS. 2 and 8). For example, two or more main girders may be provided, such as three or four, and the main girder may be erected in the center direction at portions other than both ends of the tunnel axial direction A on the inner skin plate 12. In this embodiment, it further includes inner segment vertical ribs 15 interposed between the main beam 13a and the main beam 13b. The curvature of the outer periphery of the inner skin plate 12 and the main girders 13a and 13b is larger than the inner circumference of the inner main girder 7 of the frame segment 2. Thereby, the inner segment 4 can be fitted inside the frame segment 2. The length of the inner segment 4 in the tunnel axis direction A is narrower than the sum of the frame segments 2a and 2b and wider than the frame segment 2a. The inner segment 4 is attached to the inner peripheral side of the frame segment 2 so that the inner skin plate 12 contacts the inner peripheral side end surfaces of the inner main girders 7a and 7b of the frame segments 2a and 2b. The sum of the width in the tunnel radial direction R of the inner segment 4 and the width of the inner main beam 7a of the frame segment 2a is substantially equal to the width of the outer main beam 8 of the frame segment 2a. The size of the inner segment 4 can be changed as appropriate depending on the ease of construction (see 401 to 413 in FIG. 10). Further, for example, in FIG. 10, the installation angle of the joint plate 14 with respect to the inner skin plate 12 and the circumferential end shape of the main girder 13 are appropriately set so that the inner segment 401 or 413 can be finally inserted when the inner segment is assembled. It is also possible to change.

  Further, the inner segment 4 may be divided into a plurality of inner segment pieces in the tunnel axis direction A. For example, as shown in FIG. 2, the inner segment 4 may be composed of two inner segment pieces 4a and 4b. In this case, the inner segment pieces are fixed by the inter-ring bolt 16. By configuring the inner segment with a plurality of inner segment pieces in this way, transportation and installation to the construction site is facilitated.

  Further, the inner segment 4 may have an extension control member 17 that controls the extension of the waterproof rubber 3 in the tunnel axial direction A on the inner skin plate 12. The extension control member 17 is an arc-shaped member made of steel or the like that extends in an arc shape in the circumferential direction C of the tunnel. As shown in FIG. 2, the extension control member 17 is formed on the inner skin plate 12 between a portion where the inner skin plate 12 contacts the inner main beam 7 of the frame segment 2 and an end of the inner skin plate 12 in the tunnel axial direction A. It is positioned as a projection in between, and even if the water stop rubber 3 expands, the inner main girder 7 is prevented from being displaced beyond that position. Further, during steady operation, the position of the inner segment 4 is prevented from being greatly displaced in the tunnel axis direction A.

  In the shield method, for example, a shield machine is pushed forward against a segment assembled in a TBM (tunnel boring machine), and the jack extends to advance. The thrust receiving member 5 is a member for receiving the thrust applied to the flexible segment 1 when the shield machine is excavated together with the inner segment 4 to give the flexible segment 1 rigidity. The thrust receiving member 5 is welded to a thrust receiving member mounting plate 18 made of steel or the like and a thrust receiving member joint plate 19. FIG. 6 is a partial perspective view showing a state in which the thrust receiving member 5 is installed. As shown in FIGS. 2 and 6, the thrust receiving member mounting plate 18 is fixed to the frame segment vertical rib 21 of the frame segment 2 by a thrust receiving member mounting bolt 20. The thrust receiving joint plate 19 is fixed to the main girder 13 of the inner segment 4 by a thrust receiving joint bolt 22. The thrust applied to the flexible segment 1 is transmitted through the outer main girder 8 of the frame segment, the thrust receiving member 5, the thrust receiving joint plate 19, the main girder 13 of the inner segment 4, and the inner segment vertical rib 15 (see FIG. 6). ).

  The cover plate 6 is a plate-like member made of steel or the like. As shown in FIGS. 2 and 7, the cover plate 6 is placed in close contact with the frame skin plates 10 of the frame segments 2a and 2b so as to cover the space between the frame segments 2a and 2b.

  Next, the structure after the thrust receiving material 5 is removed will be described. The thrust receiving member 5 is removed after the time point when the influence of the thrust disappears, and the state shown in FIG. 2 is changed to the state shown in FIGS. FIG. 3 is a sectional view in the tunnel axial direction showing the structure of the flexible segment 1 for shield method according to the present invention when the tunnel is completed. The frame segment is the frame segment vertical rib 21 and the inner segment is the position of the joint plate 14. FIG. 4 shows the frame segments at the positions of the joint plates 9a and 9b and the inner segments at the positions of the inner segment vertical ribs 15. In order to prevent the cover member 23 from flowing between the frame segment 2 and the inner segment 4 when the cover member 23 described later is installed after the thrust receiving member 5 is removed, A joint member 24 for closing the space between the beam 8 and the main beam 13 of the inner segment 4 can be installed. The joint member 24 is made of a stretchable material such as foam rubber or resin, and does not hinder the increase or decrease in the distance between the outer main girder 8 and the main girder 13 due to the expansion and contraction of the waterstop rubber 3. Further, after providing the joint member 24, as shown in FIG. 3, for example, a cover member 23 made of cellular concrete or the like may be installed on the entire inner peripheral side of the flexible segment 1. In the case of an earthquake or the like, it is preferable that the cover member 23 be easily crushed as the distance between the outer main girder 8 and the main girder 13 increases or decreases and does not hinder the displacement of the flexible segment 1.

  When the thrust receiving member 5 is removed, the outer main girder 8 of the frame segment 2 is arranged in the tunnel axial direction so that the distance between the outer girder 13 of the inner segment 4 and the main girder 13 of the inner segment 4 is reduced when the waterproof rubber 3 is reduced. It becomes possible to move to A the same distance as the width of the thrust receiving member mounting plate 18 of the thrust receiving member 5 in the tunnel axial direction A (see FIG. 5). Further, when the waterstop rubber 3 shrinks, it can be prevented from being deformed and broken toward the center in the tunnel radial direction.

  The configuration of the flexible segment 1 according to one embodiment of the present invention has been described above. Hereinafter, an example of the construction method of the flexible segment 1 which concerns on one Embodiment is demonstrated.

  First, the cover plate 6 is disposed between the frame segments 2a and 2b as described later, and is previously disposed in the tunnel circumferential direction C so as to be in close contact with the frame skin plate 10 of the frame segments 2a and 2b. The cover plate 6 can be formed into a ring by combining a plurality of plates as in this embodiment, or can be formed into a ring with a single strip-shaped plate.

  Next, the frame segment 2a in which the frame skin plate 10, the inner main beam 7a, the outer main beam 8, the joint plate 9a, the joint plate 9c, and the frame segment vertical rib 21 are welded, and the frame having the same structure as the frame segment 2a The segment 2b is opposed to the tunnel axis direction A so that the inner main girders 7 face each other with an interval at which the waterproof rubber 3 can be installed. Next, the frame segments 2a and 2b are respectively connected in the tunnel circumferential direction C, and a frame segment ring 25 as shown in FIG. 9 is assembled. The frame segments 2 are connected to each other by joining the joint plate 9 with joint bolts 26 for frame segments. For example, in the case of the frame segment ring 25 in FIG. 9, the frame segment 203 is connected to the frame segment 204, the frame segment 202 is connected to the frame segment 203, and the frame segment 204 is connected to the frame segment 204. The frame segment ring 25 is assembled by connecting the 205 and finally fitting the frame segment 201 which is the upper part.

  Next, the waterproof rubber 3 is interposed between the inner main beams 7 a and 7 b of the frame segments 2 a and 2 b by the waterproof rubber mounting bolts 11. As the water stop rubber 3, a ring-shaped one can be used as in the present embodiment, or a divided one can be assembled.

  Next, the thrust receiving member 5 to which the thrust receiving member mounting plate 18 and the thrust receiving joint plate 19 are welded is attached to the thrust receiving member mounting plate 18 by the thrust receiving member mounting bolt 20 and the frame segment vertical rib of the frame segment 2a. Attach to 21. This operation is performed for the entire frame segment ring 25. The thrust receiving member 5 can be attached to the frame segment 2 before the frame segment ring 25 is assembled. Moreover, after manufacturing to the state which combined the cover plate 6, the frame segment ring 25, and the thrust receiving material 5 in the factory beforehand, this was conveyed and installed in the construction site, the thrust receiving material 5 was once removed, and water stoppage was carried out. An assembly procedure such as installing the rubber 3 and attaching the thrust receiving material 5 again can be taken.

  Next, as shown in FIGS. 2 and 8, an inner segment piece 4a and an inner segment piece in which a main girder 13a, a main girder 13b, a joint plate 14a, a joint plate 14c, and an extension control member 17 are welded to the inner skin plate 12. The inner segment piece 4b having the same structure as 4a is disposed so as to contact the inner peripheral side end surfaces of the inner main beams 7a and 7b of the frame segments 2a and 2b. The inner segment 4 is assembled by fixing by the above, and the inner skin plate 12 is attached to the inner peripheral side of the frame segments 2a and 2b so that the inner skin plate 12 contacts the inner peripheral side end faces of the inner main girders 7a and 7b of the frame segments 2a and 2b. Next, the inner segments 4 are respectively connected in the tunnel circumferential direction C, and an inner segment ring 27 as shown in FIG. 10 is assembled. The inner segments 4 are connected by joining the joint plate 14a of one inner segment and the other inner segment joint plate 14c with joint bolts 28 for inner segments. For example, in the case of the inner segment ring 27 in FIG. 10, the inner segment 4 is assembled in order from the lower inner segment 407, and finally the inner segment 401 or the inner segment 413 which is the upper portion is fitted and connected. Assemble the segment ring 27.

  In parallel with the assembly of the inner segment ring 27, the inner segment 4 and the thrust receiving member 5 are connected. As shown in FIGS. 2 and 6, the connection is made at the thrust receiving member joint plate 19 of the thrust receiving member 5 where the thrust receiving member mounting plate 18 and the thrust receiving joint plate 19 are welded, and the thrust receiving joint bolt The main girder 13 of the inner segment 4 is fixed by 22. This operation is performed on the entire circumference of the inner segment ring 27, and in this state, tunnel excavation using a shield machine is performed. As another installation procedure of the thrust receiving member 5, first, the thrust receiving member 5a is attached to the frame segment 2a, then the inner segment piece 4a is attached to the thrust receiving member 5a, and then the thrust receiving member 5b is attached to the frame segment 2b. After attaching the inner segment piece 4b to the thrust receiving member 5b, the inner segment pieces 4a and 4b can be finally connected. Further, the thrust receiving member 5a is attached to the frame segment 2a, the inner segment piece 4a is attached to the thrust receiving member 5a, the inner segment pieces 4a and 4b are connected, and then the thrust receiving member 5b is attached to the inner segment piece 4b. Finally, the thrust receiving member 5b can be attached to the frame segment 2b.

  When the shield machine has advanced sufficiently and the influence of the thrust of the jack is eliminated, the thrust receiving material 5 is removed. Since the radius of curvature of the outer circumferential surface of the inner segment ring 27 is slightly smaller than the radius of curvature of the inner circumference of the inner main girder 7 of the frame segment ring 25, the inner segment ring 27 moves little in the tunnel radial direction R. On the other hand, the inner segment ring 27 is movable in the tunnel axis direction A, but is limited between the two outer main beams 8 of the frame segment ring 25.

  Next, the joint member 24 is installed so as to block the space between the outer main beam 8 of the frame segment 2 and the main beam 13 of the inner segment 4 as necessary. When the joint member 24 is installed, the cellular concrete does not enter the frame segment 2 when the cover member 23 made of cellular concrete described later is formed. Finally, the cover member 23 made of cellular concrete or the like is installed on the entire inner peripheral side of the frame segment ring 25 and the inner segment ring 27. The joint member 24 and the cover member 23 are easily compressed or crushed when a compressive force is applied.

  According to the flexible segment for shield method of the present embodiment, the tunnel main body has rigidity that can withstand thrust by the jack of the shield machine during tunnel construction, and after the thrust receiving member 5 is removed, the outer main girder of the frame segment 2 8 is the width in the tunnel axial direction A of the thrust receiving member mounting plate 18 of the thrust receiving member 5 in the tunnel axial direction A so as to reduce the distance between the main beam 13 of the inner segment 4 when the waterproof rubber 3 is reduced. Will be able to move the same distance. Further, the inner segment 4 can prevent the waterproof rubber 3 from being deformed inward in the tunnel radial direction R. Therefore, when a displacement that compresses in the tunnel axis direction A occurs due to an earthquake or the like, a large contraction displacement of about 10 times the elongation displacement can be absorbed, and the fatal destruction of the tunnel can be prevented.

  Further, by configuring the inner segment 4 from a plurality of segment pieces, the installation of the inner segment 4 at the construction site is facilitated, leading to an improvement in work efficiency.

  By providing the extension control member 17 on the inner skin plate 12 of the inner segment 4, it becomes possible to control the extension of the waterproof rubber 3 in the tunnel axial direction A.

  By installing the joint member 24 so as to block between the outer main girder 8 of the frame segment 2 and the main girder 13 of the inner segment 4, the lining material is formed between the frame segment 2 and the inner segment 4 during secondary lining. Inflowing between them can be prevented.

  Since the space remaining after the thrust receiving member 5 is removed is used, the structure is simple and the construction cost can be reduced. Moreover, since complicated processes are not required, construction with high work efficiency is enabled.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to said one Embodiment, In the range which does not deviate from the meaning, it can change suitably.

DESCRIPTION OF SYMBOLS 1 Flexible segment 2, 2a, 2b Frame segment 3 Water stop rubber 4 Inner segment 4a, 4b Inner segment piece 5, 5a, 5b Thrust receiving material 6 Cover plate 7, 7a, 7b Inner main girder 8 Outer main girder 9, 9a , 9b, 9c Joint plate 10 Frame skin plate 11 Waterproof rubber mounting bolt 12 Inner skin plate 13, 13a, 13b Main girder 14, 14a, 14b, 14c Joint plate 15 Inner segment vertical rib 16 Ring bolt 17 Extension control member 18 Thrust receiving member mounting plate 19 Thrust receiving member joint plate 20 Thrust receiving member mounting bolt 21 Frame segment vertical rib 22 Thrust receiving member joint bolt 23 Cover member 24 Joint member 25 Frame segment ring 26 Frame segment joint bolt 27 Inside segment ring 28 Inside Joint bolt for segment 101-105 Flexible segment 201-20 Radial T1 of the circumferential direction R tunnels axial C tunnel in the frame segments 401-413 segment A tunnel, T2 standard segment

Claims (5)

A curved plate-like frame skin plate forming an outer peripheral surface, and arc-shaped inner main girder and outer main girder that are erected in the center direction at both ends of the frame skin plate in the tunnel axis direction, A pair of frame segments in which the girder is wider than the inner main girder in the radial direction of the tunnel, with the inner main girder facing each other with a gap in the axial direction,
A waterproof rubber interposed between the inner main beams of the pair of frame segments and capable of expanding and contracting in the axial direction;
A curved plate-like inner skin plate whose curvature is larger than the inner circumference of the inner main girder, and two or more arc-shaped main girders that are erected in the center direction at at least both ends in the axial direction of the inner skin plate An inner segment that is attached to the inner peripheral side of the pair of frame segments to suppress deformation to the inside of the waterproof rubber, and
A thrust receiving member detachably installed between the outer main girder of the pair of frame segments and the main girder of the inner segment;
By removing the thrust receiving material, the outer main girder of the pair of frame segments can move in the axial direction by the same distance as the axial width of the thrust receiving material, and the axial displacement Can absorb,
Flexible segment for shield method. The inner segment is divided into a plurality of segment pieces in the axial direction.
The flexible segment for shield construction according to claim 1. The inner segment has an extension control member that controls extension of the water stop rubber in the axial direction on the inner skin plate.
The flexible segment for shield construction according to claim 1 or 2.   The said thrust receiving material is removed from the flexible segment for shield methods as described in any one of Claims 1 thru | or 3, and between the said outer main girder of the said pair of frame segment, and the said main girder of the said inner segment. A flexible segment for a shield method, which is provided with a joint member for blocking and preventing a lining material from flowing in during secondary lining. A plurality of flexible segments for shield method according to any one of claims 1 to 3 are joined in the circumferential direction of the tunnel to form a frame segment ring and an inner segment ring,
When the thrust is no longer affected, the thrust receiving material is removed;
Construction method of flexible segment for shield method.

Images