JP6359375B2 - Tunnel excavator and seal diameter switching method during tunnel construction - Google Patents

Description

  The present invention relates to a tunnel excavator that can maintain water stopping performance even when the outer diameter of a tunnel is changed, and a seal diameter switching method during tunnel construction.

  At the time of tunnel construction, for example, the cross-sectional shape of the tunnel may be changed according to the distance between the adjacent tunnels or the distance between the tunnel and the underground structure. That is, when the distance between the adjacent tunnels or the distance between the tunnel and the underground structure is shortened, the cross-sectional shape of the tunnel may be reduced from the viewpoint of safety during tunnel construction, the strength of the tunnel, and the like.

  Therefore, various tunnel excavators that can change the cross-sectional shape of the tunnel during tunnel construction have been provided. And as such a conventional tunnel excavator, it is disclosed by patent document 1, for example.

JP 2007-247211 A

  However, in the conventional tunnel excavator, in addition to the existing configuration for forming a normal tunnel cross-sectional shape, a partition ring for forming a new tunnel cross-sectional shape and a reaction force receiver for this. I had to increase the number of propulsion jacks. Thereby, in the conventional tunnel excavator, the apparatus configuration is complicated and the construction procedure may be complicated.

  In particular, when forming a new tunnel cross-sectional shape, water stoppage performance is ensured between the excavator body and the normal segment, between the bulkhead ring and the new segment, and between the excavator body and the bulkhead ring. It was necessary to consider enough.

  Accordingly, the present invention solves the above-described problem, and provides a tunnel excavator and a seal diameter switching method at the time of tunnel construction that can easily maintain water stopping performance even if the outer diameter of the tunnel is changed. The purpose is to provide.

The tunnel excavator according to the first invention for solving the above-described problems is
A cylindrical excavator body,
A large-diameter still water seal that is provided over the entire circumferential direction on the inner peripheral surface of the excavator body, and seals a gap between the inner peripheral surface of the excavator body and the existing large-diameter segment;
A tail plate that is disposed inside the large-diameter water stop seal in the tunnel radial direction and has an annular shape whose outer peripheral surface is in close contact with the large-diameter water seal;
Provided across the entire circumferential direction of the inner peripheral surface of the tail plate, and seals a gap between the inner peripheral surface of the tail plate and the existing small diameter segment having a smaller diameter than the existing large diameter segment. A water stop seal for small diameters,
The tail plate is detachably supported on the inner peripheral surface of the excavator body, and the large-diameter water seal and the small-diameter water seal are attached to the existing small-diameter segment assembled at the tunnel small-diameter cross-section end position. In the tunnel excavator comprising the excavator main body and the attachment member removed from the tail plate when it reaches ,
The tail plate and the small diameter water stop seal are composed of a plurality of plate pieces and seal pieces divided by the same quantity as the quantity of the small diameter segments per segment ring,
A fixing means for detachably attaching one plate piece and the seal piece to an outer peripheral surface of one small-diameter segment assembled at a tunnel small-diameter cross-section start position is provided .

The tunnel excavator according to the second invention for solving the above-mentioned problems is
The small-diameter segment assembled at the tunnel small-diameter cross-section start position has a bolt hole penetrating the small-diameter segment in the tunnel radial direction,
The fixing means includes a bolt inserted into the bolt hole from the inner side in the tunnel radial direction and screwed to the plate piece .

A tunnel excavator according to a third invention for solving the above-described problem is
A fitting protrusion formed on one end surface in the arc length direction of the plate piece ;
A fitting recess is formed on the other end surface in the arc length direction of the plate piece , and is fitted with the fitting protrusion.

The seal diameter switching method at the time of tunnel construction according to the fourth invention for solving the above problem is as follows.
The inside of the excavator main body includes a large-diameter water-stop seal provided on the inner peripheral surface of the excavator main body to be dug, and a small-diameter water-stop seal disposed inside the large-diameter water-stop seal in the tunnel radial direction. Seal the gap between the peripheral surface and the existing small-diameter segment,
When the large-diameter water-stop seal and the small-diameter water-stop seal reach the existing small-diameter segment assembled at the tunnel small-diameter cross-section end position, the small-diameter water-stop seal is connected to the inner peripheral surface of the excavator body. From the rear end surface of the large-diameter segment assembled at the tunnel large-diameter cross-section start position,
In the seal diameter switching method during tunnel construction for sealing the gap between the inner peripheral surface of the excavator body and the existing large diameter segment by the large diameter water stop seal ,
A seal piece obtained by dividing the small-diameter water stop seal by the same number as the small-diameter segment per one segment ring is attached to the outer peripheral surface of the small-diameter segment assembled at the tunnel small-diameter cross-section start position.
When the large-diameter water stop seal reaches the tunnel small-diameter cross-section start position, the seal piece is detached from the small-diameter segment assembled at the tunnel small-diameter cross-section start position, and the inner peripheral surface of the excavator body Attached to the
A plurality of the sealing pieces attached to the inner peripheral surface of the excavator main body are assembled in an annular shape to constitute the small diameter water stop seal .

The seal diameter switching method at the time of tunnel construction according to the fifth invention for solving the above-mentioned problem is as follows.
An annular tail plate composed of a plurality of plate pieces divided by the same quantity as the quantity of the small diameter segment per segment ring is provided between the large diameter water seal and the small diameter water seal. Provided,
The plate piece and the seal piece are fixed to the outer peripheral surface of the small diameter segment by inserting a bolt from the inner peripheral surface side to the outer peripheral surface side of the small diameter segment assembled at the tunnel small diameter cross-section start position. Features.

  Therefore, according to the tunnel excavator and the tunnel diameter switching method at the time of tunnel construction according to the present invention, the existing small-diameter segment is arranged on the inner side in the tunnel radial direction of the large-diameter water-stop seal that can be in close contact with the existing large-diameter segment. Even if the outer diameter of the tunnel is changed, the water stop performance can be improved by arranging a small diameter water stop seal that can be closely attached to the inner surface of the excavator main body. Can be easily maintained.

1 is a schematic configuration diagram of a tunnel excavator according to an embodiment of the present invention. It is the figure which showed the seal structure in a tunnel excavator, Comprising: (a) is a longitudinal cross-sectional view of the seal structure at the time of tunnel cross-section diameter expansion, (b) is a longitudinal cross-sectional view of the seal structure at the time of tunnel cross-section diameter reduction. It is the perspective view which showed the division | segmentation state of a tail seal and a tail plate. It is the cross-sectional view which showed the fitting structure of the tail plate. (A)-(f) is the figure which showed the seal diameter switching operation | movement at the time of tunnel construction in order.

  Hereinafter, a tunnel excavator and a seal diameter switching method during tunnel construction according to the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, the tunnel excavator 1 is provided with a cylindrical excavator body 11, and a disc-shaped cutter head 12 is rotatable at the front end of the excavator body 11. It is supported. A large number of cutters 13 are mounted on the front surface of the cutter head 12. Therefore, the face can be excavated in the ground by rotating the cutter head 12.

  In addition, an erector device 14 is supported in the rear end portion of the excavator body 11 so as to be movable in the tunnel axial direction, the tunnel radial direction, and the tunnel circumferential direction. This erector device 14 is a device that grips the segments S1 and S2 as the lining members and assembles them along the circumferential direction of the tunnel well having a circular cross section. The segments S1 and S2 are formed on the tunnel well wall. It is a ring piece that follows. Therefore, by driving the erector device 14, the plurality of segments S1 and S2 can be assembled in a ring shape along the circumferential direction of the tunnel mine.

  In addition, segment S1 is a segment for tunnel diameter expansion (for large diameter) used when expanding the outer diameter of the tunnel having a circular cross section. On the other hand, the segment S2 is a segment for tunnel diameter reduction (for small diameter) used when reducing the outer diameter of the tunnel having a circular cross section.

  Thereby, the outer diameter of the segment ring which assembled the segment S1 in the ring shape is larger than the outer diameter of the segment ring which assembled the segment S2 in the ring shape. Further, the inner diameters of the above-described segment rings have the same diameter dimension, and the thickness of the segment S1 is formed to be thicker than the thickness of the segment S2.

  Therefore, when the tunnel excavator 1 advances, a large-diameter tunnel constructed by assembling the segment S1 and a small-diameter constructed by assembling the segment S1 inside the tunnel mine excavated by the cutter head 12 in the radial direction. It is possible to construct the tunnel selectively and continuously.

  Further, a plurality of shield jacks (propulsion jacks) 15 are arranged on the inner peripheral surface of the excavator body 11 along the circumferential direction of the inner peripheral surface. A spreader 15a is attached to the rod tip of each shield jack 15, and the spreader 15a faces the front end surfaces of the existing segments S1 and S2 in the tunnel axis direction.

  That is, the shield jack 15 extends rearward in the tunnel axis direction, and applies the excavation reaction force (propulsion force) to the excavator body 11 by pressing the spreader 15a against the front end surfaces of the existing segments S1 and S2. be able to. Thereby, the excavator main body 11 can advance in the ground by excavation reaction force generated when the shield jack 15 presses the segments S1 and S2.

  Here, as shown in FIGS. 1 and 2 (a) and 2 (b), in the tunnel excavator 1, the seal structure at the time of tunnel expansion is different from the seal structure at the time of tunnel reduction. Therefore, the seal structure can be switched according to switching between the assembly of the segment S1 and the assembly of the segment S2 (according to the expansion / contraction of the outer diameter of the tunnel). In the tunnel excavator 1 shown in FIG. 1, the seal structure at the time of tunnel diameter expansion is shown in the upper part, while the seal structure at the time of tunnel diameter reduction is shown in the lower part so that they can be easily compared. It is shown.

  First, the seal structure at the time of tunnel diameter expansion will be described with reference to FIG. 1 and FIG.

  As shown in FIGS. 1 and 2 (a), a plurality of stages of tail seals (water blocking seals for large diameter) 21 are provided on the inner peripheral surface of the rear end portion of the excavator body 11 in the tunnel axis direction. ing. These tail seals 21 are provided over the entire circumferential direction on the inner peripheral surface of the excavator body 11, and are in close contact with the outer peripheral surface of the existing segment S1 so as to be slidable. That is, the ring-shaped tail seal 21 seals a gap between the inner peripheral surface of the excavator body 11 and the outer peripheral surface of the existing segment S1, and soil and water enter the excavator body 11 from the gap. Prevents inflow.

  Next, the seal structure at the time of tunnel diameter reduction will be described with reference to FIGS. 1 and 2B.

  As shown in FIGS. 1 and 2 (b), in the seal structure at the time of tunnel diameter reduction, the tail seal (water blocking seal for small diameter) 31, the tail plate 32, and the mounting bracket (mounting member) 33 are connected to the tail. The seal 21 is provided on the inner side in the tunnel radial direction. That is, in the seal structure at the time of tunnel diameter reduction, a double seal structure in which the two tail seals 21 and 31 are arranged so as to overlap in the tunnel diameter direction is adopted.

  Specifically, an annular tail plate 32 is disposed inside the tail seal 21 in the tunnel radial direction. At this time, the tail seal 21 is in close contact with the outer peripheral surface of the tail plate 32 so as to be slidable. That is, the tail seal 21 at the time of tunnel diameter reduction seals the gap between the inner peripheral surface of the excavator main body 11 and the outer peripheral surface of the existing tail plate 32, and soil and water can be excreted from the gap. 11 is prevented from flowing into.

  A plurality of mounting brackets 33 are detachably attached to the rear end portion of the tail plate 32. These mounting brackets 33 are arranged at equal intervals in the circumferential direction of the tail plate 32 and are detachably mounted on the front side in the tunnel axial direction of the tail seal 21 on the inner circumferential surface of the excavator body 11.

  Furthermore, a plurality of stages of tail seals 31 are provided on the inner peripheral surface of the tail plate 32 in the tunnel axis direction. These tail seals 31 are provided over the entire circumferential direction on the inner peripheral surface of the tail plate 32, and are in close contact with the outer peripheral surface of the existing segment S2 so as to be slidable. That is, the ring-shaped tail seal 31 seals the gap between the inner peripheral surface of the tail plate 32 and the outer peripheral surface of the existing segment S2, and soil and water flow into the excavator body 11 from the gap. To prevent it.

  As shown in FIG. 3, the tail seal 31 and the tail plate 32 have a tunnel circumferential direction division structure including a plurality of seal pieces 31 a and plate pieces 32 a, respectively.

  At this time, the number of divisions of the tail seal 31 and the tail plate 32 is the same as the number of segment rings divided at the time of tunnel diameter reduction, that is, the number of segments S2 per one segment ring. On the other hand, one seal piece 31a and plate piece 32a are arranged opposite to each other in the tunnel radial direction. That is, the seal piece 31a and the plate piece 32a are ring pieces along the outer peripheral surface of the segment S2, and are detachably attached to the outer peripheral surface of the segment S2.

  Further, the thickness of the seal-integrated segment in which the seal piece 31a and the plate piece 32a are attached to the segment S2 as described above is equal to or less than the thickness of the segment S1. In other words, when the seal piece 31a and the plate piece 32a are attached to the segment S2, the tunnel radial thickness between the outer peripheral surface of the plate piece 32a and the outer peripheral surface of the segment S2 (the tip of the seal piece 31a and the plate 32a The thickness in the tunnel radial direction between the outer peripheral surface and the outer peripheral surface is equal to or less than the thickness obtained by subtracting the thickness of the segment S2 from the thickness of the segment S1.

  Further, the seal piece 31a attached to the segment S2 is accommodated without protruding from the outer peripheral surface of the segment S2, and the width of the plate piece 32a (the length in the tunnel axis direction) is the width of the segment S2. It is formed in the following length.

  3 and 4, a fitting convex portion 32b is formed on one end surface in the arc length direction of the plate piece 32a, while a fitting concave portion is formed on the other end surface in the arc length direction of the plate piece 32a. 32c is formed. Thereby, when assembling the plurality of plate pieces 32a in an annular shape, between the adjacent plate pieces 32a, the fitting convex portion 32b in one plate piece 32a and the fitting concave portion 32c in the other plate piece 32a are formed. It is designed to fit.

  Therefore, the assembly of the plurality of seal pieces 31a and the plate pieces 32a into the tail seal 31 and the tail plate 32 is performed by assembling the segment S2 to which the seal pieces 31a and the plate pieces 32a are attached by the erector device 14, thereby It will be done in parallel with the assembly.

  At this time, the attached seal piece 31a and plate piece 32a do not protrude from the outer peripheral surface of the segment S2 to the periphery thereof, and do not protrude beyond the thickness of the segment S1. That is, when assembling the segment S2 to which the seal piece 31a and the plate piece 32a are attached, the seal piece 31a and the plate piece 32a are provided on the inner peripheral surface of the excavator body 11, the existing segment S1, and the existing seal. There is no interference with the integrated segment.

  Therefore, when a tunnel is constructed by the tunnel excavator 1, the excavator reaction force is obtained from the existing segment S1 or segment S2 by rotating the cutter head 12 and extending the shield jack 15, and the excavator body. Move 11 forward. Thereby, many cutters 13 mounted on the rotating cutter 12 excavate the face in the ground. At the same time, at the rear side of the shortened shield jack 15 in the tunnel axis direction, the new segment S1 or segment S2 is sequentially assembled along the tunnel circumferential direction by driving the erector device 14.

  Next, the switching operation of the seal structure when expanding or reducing the tunnel outer diameter during excavation will be described in detail with reference to FIGS.

  First, as shown in FIG. 5A, when constructing a tunnel having a large-diameter cross section, the segment S <b> 1 is assembled and water is stopped only by the tail seal 21.

  At this time, when constructing the tunnel by assembling the segment S1, for example, when the distance between the tunnel having the large diameter cross section and the existing preceding tunnel or the underground structure is equal to or less than a predetermined distance, May adversely affect tunnel construction.

  Therefore, in order to avoid the above-described problem, when the distance between the large-diameter tunnel in the middle of construction and the existing preceding tunnel or underground structure is equal to or less than a predetermined distance, the assembly of segment S1 is performed by assembling segment S2. In addition, the sealing device is also switched as the tunnel outer diameter becomes smaller.

  And as shown in FIG.5 (b), the assembly of segment S2 to which the seal piece 31a and the plate piece 32a were attached is started in a tunnel small diameter cross-section start position.

  At this time, a plurality of bolt holes S2a are formed through the segment S2 in the segment thickness direction, and fixing bolts (fixing means) 41 are inserted into the bolt holes S2a, respectively. Yes. The fixing bolt 41 passes through the bolt hole S2a from the inner peripheral surface side toward the outer peripheral surface side, and the bolt tip is fitted into the inner peripheral surface of the plate piece 32a. Thus, by fixing the plate piece 32a having the seal piece 31a by the fixing bolt 41 through the bolt hole S2a, the seal piece 31a and the plate piece 32a are attached to the segment S2.

  Next, when the assembly of one ring of the segment S2 is completed, the shield jack 15 is extended by one ring of the segment S2, and the spreader 15a is extended to the segment S2 (segment ring to which the tail seal 31 and the tail plate 32 are attached). ) To the front end face.

  Accordingly, as shown in FIG. 5C, the excavator body 11 moves forward by one ring of the segment S2, and the tail seal 21 reaches the tunnel small-diameter cross-section start position. That is, the tail seal 21 is in close contact with the outer peripheral surface of the tail plate 32 attached to the segment 2S.

  Thereafter, the tail plate 32 is attached to the inner peripheral surface of the excavator main body 11 via the plurality of attachment fittings 33, and the fixing bolt 41 is pulled out. Therefore, the tail seal 31 and the tail plate 32 are released from being fixed to the segment S2 and are fixed to the excavator body 11. That is, by switching the fixing of the tail seal 31 and the tail plate 32 from the segment S2 side to the excavator body 11 side, the seal structure is changed from the single seal structure by the tail seal 21 to the double seal by the tail seals 21 and 31. Switch to structure.

  A plug 42 is fitted into the bolt hole S2a from which the fixing bolt 41 is pulled out. Thereby, soil and water can be prevented from flowing into the excavator body 11 from the bolt hole S2a.

  And as shown in FIG.5 (d), the tunnel which becomes a small diameter cross section is constructed by performing water stop by the tail seals 21 and 32, assembling the segment S2.

  Further, when the distance between the small diameter tunnel and the existing preceding tunnel or underground structure exceeds a predetermined distance, the assembly of the segment S2 is switched to the assembly of the segment S1, and the outer diameter of the tunnel is increased. To some extent, the sealing device is also switched.

  That is, as shown in FIG. 5E, the assembly of the segment S1 is started at the tunnel large-diameter section start position.

  Thereafter, when the tail seals 21 and 31 reach the segment S2 assembled at the tunnel small-diameter cross-section end position located immediately before the tunnel large-diameter cross-section start position, the mounting bracket 33 is removed from the excavator 11 and the tail plate 32. Therefore, the tail seal 31 and the tail plate 32 are released from being fixed to the excavator body 11. That is, since the tail seal 31 and the tail plate 32 are not fixed to the excavator body 11 side and the segment S2 side, the seal structure is changed from the double seal structure by the tail seals 21 and 31 to 1 by the tail seal 21. Switch to heavy seal structure.

  Then, as shown in FIG. 5 (f), the excavator body 11 moves forward by using the segment S 1 as a reaction force receiver for the shield jack 15. At this time, since the tail seal 31 and the tail plate 32 are not fixed to the excavator body 11, the tail seal 31 and the tail plate 32 come into contact with the rear end surface of the segment S1 assembled at the tunnel large-diameter cross-section start position and move forward in the tunnel axial direction. Movement is restricted. That is, the tail seal 31 and the tail plate 32 are left behind at the tunnel small-diameter cross-section end position.

  Therefore, according to the tunnel excavator and the seal diameter switching method during tunnel construction according to the present invention, the tail seal 31 is disposed inside the tail seal 21 in the tunnel radial direction, and the tail seal 31 is disposed inside the excavator body 11. By supporting the peripheral surface so as to be detachable, the water stop performance can be easily maintained even if the outer diameter of the tunnel is changed.

  The tunnel excavator according to the present invention can maintain water stopping performance even when the outer diameter of the tunnel is changed during excavation, and therefore can be used extremely beneficially in the tunnel construction technical field.

DESCRIPTION OF SYMBOLS 1 Tunnel excavator 11 Excavator main body 12 Cutter head 13 Cutter 14 Elector apparatus 15 Shield jack 15a Spreader 21, 31 Tail seal 31a Seal piece 32 Tail plate 32a Plate piece 32b Fitting convex part 32c Fitting concave part 33 Fixing bracket 41 Fixing Bolt 42 Plug S1, S2 Segment S2a Bolt hole

Claims (5)

A cylindrical excavator body,
A large-diameter still water seal that is provided over the entire circumferential direction on the inner peripheral surface of the excavator body, and seals a gap between the inner peripheral surface of the excavator body and the existing large-diameter segment;
A tail plate that is disposed inside the large-diameter water stop seal in the tunnel radial direction and has an annular shape whose outer peripheral surface is in close contact with the large-diameter water seal;
Provided across the entire circumferential direction of the inner peripheral surface of the tail plate, and seals a gap between the inner peripheral surface of the tail plate and the existing small diameter segment having a smaller diameter than the existing large diameter segment. A water stop seal for small diameters,
The tail plate is detachably supported on the inner peripheral surface of the excavator body, and the large-diameter water seal and the small-diameter water seal are attached to the existing small-diameter segment assembled at the tunnel small-diameter cross-section end position. In the tunnel excavator comprising the excavator main body and the attachment member removed from the tail plate when it reaches ,
The tail plate and the small diameter water stop seal are composed of a plurality of plate pieces and seal pieces divided by the same quantity as the quantity of the small diameter segments per segment ring,
A tunnel excavator comprising a fixing means for detachably attaching one plate piece and the seal piece to an outer peripheral surface of one small-diameter segment assembled at a tunnel small-diameter cross-section start position . The tunnel excavator according to claim 1,
The small-diameter segment assembled at the tunnel small-diameter cross-section start position has a bolt hole penetrating the small-diameter segment in the tunnel radial direction,
The fixing means includes a bolt that is inserted into the bolt hole from the inner side in the tunnel radial direction and screwed to the plate piece.
Tunnel excavator characterized by that. In the tunnel excavator according to claim 1 or 2,
A fitting protrusion formed on one end surface in the arc length direction of the plate piece ;
A tunnel excavator, comprising: a fitting recess that is formed on the other end surface in the arc length direction of the plate piece and fits with the fitting projection. The inside of the excavator main body includes a large-diameter water-stop seal provided on the inner peripheral surface of the excavator main body to be dug, and a small-diameter water-stop seal disposed inside the large-diameter water-stop seal in the tunnel radial direction. Seal the gap between the peripheral surface and the existing small-diameter segment,
When the large-diameter water-stop seal and the small-diameter water-stop seal reach the existing small-diameter segment assembled at the tunnel small-diameter cross-section end position, the small-diameter water-stop seal is connected to the inner peripheral surface of the excavator body. From the rear end surface of the large-diameter segment assembled at the tunnel large-diameter cross-section start position,
In the seal diameter switching method during tunnel construction for sealing the gap between the inner peripheral surface of the excavator body and the existing large diameter segment by the large diameter water stop seal ,
A seal piece obtained by dividing the small-diameter water stop seal by the same number as the small-diameter segment per one segment ring is attached to the outer peripheral surface of the small-diameter segment assembled at the tunnel small-diameter cross-section start position.
When the large-diameter water stop seal reaches the tunnel small-diameter cross-section start position, the seal piece is detached from the small-diameter segment assembled at the tunnel small-diameter cross-section start position, and the inner peripheral surface of the excavator body Attached to the
A seal diameter switching method at the time of tunnel construction , wherein a plurality of the seal pieces attached to the inner peripheral surface of the excavator body are assembled in an annular shape to constitute the small diameter water stop seal . In the seal diameter switching method during tunnel construction according to claim 4,
An annular tail plate composed of a plurality of plate pieces divided by the same quantity as the quantity of the small diameter segment per segment ring is provided between the large diameter water seal and the small diameter water seal. Provided,
The plate piece and the seal piece are fixed to the outer peripheral surface of the small diameter segment by inserting a bolt from the inner peripheral surface side to the outer peripheral surface side of the small diameter segment assembled at the tunnel small diameter cross-section start position. A method for switching the seal diameter during tunnel construction.

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