JP2018091101A - Shield machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shield machine capable of reducing a tail void and reducing a back-filling amount.SOLUTION: A shield machine 1 for excavating a circular tunnel is provided with a tubular skin plate 21 (a front barrel part skin plate) with a generally same cross section shape with the non circular tunnel and is provided with a front barrel part 2 for excavating a pit face with a cutter drum 22 situated in a front tip, a tail part 3 which has a plurality of skin plate 31 (a tail part skin plate) with each cross section shape as a plurality of divided area which divides a cross section of the skin plate 21, an erector 44a, 44b which construct an inner wall body with a segment S at each inner periphery of a plurality of skin plate 31 and a skin plate 41 (an intermediate barrel part skin plate) which has the same cross section shape as the skin plate 21 and is equipped with an intermediate barrel part 4 which connects a front barrel part 2 with a tail part 3.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a shield machine for excavating a non-circular tunnel.

  In general, a shield machine is a shield jack that connects a front body part that digs a face at the front part in the traveling direction, a tail part that performs lining by assembling segments at the rear part, and a front body part and a tail part, and is a propulsion equipment. It consists of a middle torso equipped with etc. inward. When constructing a tunnel with a large cross-section with such a shield machine by non-open cutting, a method of excavating a plurality of times with the shield machine and connecting them to each other is adopted (for example, see Patent Document 1). The less the number of excavations with the shield machine, the shorter the construction period. Therefore, it is considered to reduce the number of excavations by enlarging the shield machine and increasing the cross-sectional area of the tunnel excavated at a time.

Japanese Patent Laid-Open No. 2000-73585

  However, when the shield machine is enlarged, the load acting from the outside increases, so that it is necessary to increase the strength of the skin plate as the outer shell. In this case, the strength of the skin plate can be reinforced by the ring gutter which is a steel ring-shaped member in the front body part and the middle body part, but in the tail part, it is necessary to assemble a segment on the inner wall of the skin plate. Therefore, the strength must be increased by the thickness of the skin plate itself. In particular, a non-circular shield machine such as a rectangle has a larger amount of stress and deflection than a circular shield machine, and the skin plate thickness at the tail increases. For this reason, there is a problem that the tail void becomes large and the amount of backfill injection increases. In addition, when constructing with high water pressure, there is a similar problem because it is necessary to ensure the strength of the skin plate.

  The present invention has been made in consideration of the above-described circumstances, and an object of the present invention is to provide a shield machine that can reduce tail voids and reduce the amount of backfill injection.

In order to achieve the above object, the present invention is a shield machine for excavating a non-circular tunnel, comprising a cylindrical front trunk skin plate having substantially the same cross-sectional shape as the non-circular tunnel, at the front end. A front body portion for excavating the face with the disposed cutter drum, and a tail portion including a plurality of tail portion skin plates each having a plurality of divided regions obtained by dividing a cross section of the front body portion skin plate, An erector that constructs an inner wall body by assembling segments on the inner periphery of each of the plurality of tail skin plates, and a middle torso skin plate having the same cross-sectional shape as the front torso skin plate. And a middle body part for connecting the tail part to the tail part.
Furthermore, in the present invention, the front body skin plate has a rectangular cross section, and the plurality of tail skin plates each have a plurality of divided regions obtained by dividing the longitudinal direction of the front body skin plate. It is good also as a cross-sectional shape.
Further, in the present invention, a plurality of shield jacks for obtaining a reaction force from the existing segment during propulsion are attached to the inner periphery of the middle trunk skin plate, and the inner trunk skin plate is hung inside the middle trunk skin plate. A segment pressing jack for pressing an existing segment during propulsion may be attached to the passed column.

  According to the present invention, by dividing the tail portion, it is possible to reduce the thickness of the skin plate as compared with the case where the tail body has the same cross-sectional shape as that of the front body portion. As a result, even if the shield machine is enlarged and the cross-sectional area of the tunnel excavated at a time is increased, the tail void can be reduced and the amount of backfill injection can be reduced.

It is a figure which shows the structure of embodiment of the shield machine which concerns on this invention. It is the figure which looked at the tail part shown in Drawing 1 from the back side. It is a figure which shows the span of the width direction of the front trunk | drum and tail part shown in FIG. It is the figure which looked at the middle trunk | drum shown in FIG. 1 from the back side.

  Embodiments of a shield machine according to the present invention will be described below with reference to the accompanying drawings.

  The present embodiment is a shield machine 1 that excavates a rectangular (rectangular) non-circular tunnel whose cross section is elongated in the width direction (horizontal direction) and constructs an inner wall body thereof by a segment S. Referring to FIG. 1, the shield machine 1 connects the front body part 2 for excavating the face at the front part, the tail part 3 for lining by the segment S at the rear part, and the front body part 2 and the tail part 3. At the same time, it is composed of a middle body 4 equipped with propulsion equipment inward.

  The front trunk portion 2 includes a skin plate 21 made of a rectangular cylindrical steel shell having a cross-sectional shape that is substantially the same as that of a noncircular tunnel to be excavated and whose cross section is elongated in the width direction. Then, four cutter drums 22 provided in the plurality of disk cutters are arranged at the front end of the front body portion 2 so as to be rotatable in the width direction. For example, the cutter drum 22 excavates a tunnel having a square cross section by using the operating principle of the triangle of the Ruro by rotating the three radially projecting arms eccentrically.

  A chamber 24 partitioned by a partition wall 23 is formed inside the skin plate 21 located on the rear side of the cutter drum 22. Excavation slip is taken into the chamber 24 as the cutter drum 22 rotates. The excavation slot is taken out from the chamber 24 by a screw conveyor or the like (not shown) and discharged backward.

  Referring to FIGS. 1 and 2, the tail portion 3 is divided into a first divided tail portion 3a and a second divided tail portion 3b. Each of the first divided tail portion 3a and the second divided tail portion 3b includes a skin plate 31 made of a rectangular cylindrical steel shell. Each of the skin plates 31 of the first divided tail portion 3a and the second divided tail portion 3b has a plurality of divided regions obtained by dividing the cross section of the skin plate 21 of the front body portion 2 as the respective sectional shapes. In the present embodiment, the skin plate 31 has a cross-sectional shape obtained by dividing the skin plate 21 of the front body portion 2 into left and right parts (the width direction that is the longitudinal direction is divided into two parts). The skin plate 31 of the first divided tail portion 3a and the skin plate 31 of the second divided tail portion 3b are arranged side by side in the width direction, and opposing surfaces are joined and integrated by welding or the like.

  As shown in FIG. 3A, when the span in the width direction of the skin plate 21 (front body portion 2) is W, the spans of the first divided tail portion 3a and the second divided tail portion 3b (skin plate 31) are as follows. As shown in FIG. 3B, W / 2. Therefore, as shown in FIG. 3C, the first divided tail is compared with the case where the skin plate 31a is configured with the same span W as the skin plate 21 (front body portion 2) without dividing the tail portion 3. The external force acting on the portion 3a and the second divided tail portion 3b is reduced. Accordingly, the thickness T1 of the skin plate 31 in the first divided tail portion 3a and the second divided tail portion 3b can be made thinner than the thickness T0 of the skin plate 31 of the span W, and the tail void can be reduced. Can do.

  In the present embodiment, the cross-sectional shape of the skin plate 31 is a rounded rectangle in consideration of the assembly of the segment S. Accordingly, a concave portion 32 extending in the front-rear direction is formed at a location where the rounded corner portions face each other at the joint portion between the first divided tail portion 3a and the second divided tail portion 3b. Therefore, a plate-like member 33 is provided to prevent the earth and sand from entering the recess 32. The plate member 33 is joined to the rounded corners of the skin plate 31 by welding, for example.

  1 and 4, the middle body portion 4 includes a skin plate 41 made of a rectangular cylindrical steel shell having the same cross-sectional shape as the skin plate 21 of the front body portion 2. A ring garter 42 is provided on the inner periphery of the skin plate 41 over the entire periphery. The ring gutter 42 is a steel ring-shaped member, and functions as a reinforcing member that reinforces the strength of the skin plate 21. The ring gutter 42 is provided with a plurality of small chambers, and a shield jack 43 serving as propulsion equipment is accommodated in the small chambers. The shield jack 43 obtains a reaction force from the existing segment S, and propels the shield machine 1 by extending from the contracted state. A plurality of shield jacks 43 are attached to the inner periphery of the skin plate 41 at equal intervals so that the reaction force from the segment S acts uniformly on the entire periphery of the skin plate 41.

  In the inner circumferential side space of the ring garter 42, an erector 44a that assembles the segment S on the inner circumference of the first divided tail portion 3a to construct an inner wall body, and a segment S that is assembled on the inner circumference of the second divided tail portion 3b. An erector 44b for constructing the inner wall body is provided. The erector 44a and the erector 44b are mechanisms that grip the segment S before installation and transfer the segment S to a predetermined angular position.

  Further, a steel reinforcing column 45 that reinforces the strength of the skin plate 41 (ring gutter 42) is stretched in the vertical direction substantially at the center in the width direction of the skin plate 41 (ring gutter 42). Segment pressing jacks 46 a and 46 b are attached to the reinforcing column 45 to prevent the displacement of the existing segment S when the shield machine 1 is propelled.

  In the present embodiment, the force necessary for propelling the shield machine 1 is configured to be obtained by a plurality of shield jacks 43. Since this shield jack 43 is attached to the inner periphery of the skin plate 41 at equal intervals, only from the three sides of the segment S assembled on the inner periphery of each of the first divided tail portion 3a and the second divided tail portion 3b. A reaction force is obtained, and the force acts on the existing segment S non-uniformly. Therefore, the segment pressing jacks 46a and 46b extend from the contracted state to press one side where the force of the shield jack 43 of the existing segment S does not act. Thereby, the deviation of the existing segment S can be prevented when the shield machine 1 is propelled.

  The pressing force of the segment pressing jacks 46 a and 46 b is set to be smaller than the pressing force of the shield jack 43. This is because the pressing force of the segment pressing jacks 46 a and 46 b acts on the reinforcing column 45 as a reaction force from the segment S. That is, the reinforcing column 45 is stretched in the vertical direction and has a structure that is weak against the force applied in the front-rear direction, so that an excessive reaction force does not act on the reinforcing column 45.

  Further, in the present embodiment, an example in which four cutter drums 22 are provided in the front barrel portion 2 has been described, but the type and number of cutter drums 22 provided in the front barrel portion 2 can be set as appropriate. Furthermore, although the example which divides | segments the tail part 3 into two was demonstrated in this embodiment, the division | segmentation number of the tail part 3 can be set suitably. Furthermore, in the present embodiment, the skin plate 21 of the front body portion 2 and the skin plate 31 of the middle body portion 4 are configured separately, but the skin plate 21 and the skin plate 31 may be integrated.

As described above, the present embodiment is a shield machine 1 for excavating a non-circular tunnel, and includes a cylindrical skin plate 21 (front body skin plate) having substantially the same cross-sectional shape as the non-circular tunnel. A plurality of skin plates 31 (tails) each having a plurality of divided regions obtained by dividing a cross section of the skin plate 21 and a front body portion 2 for excavating the face with a cutter drum 22 disposed at a front end. Tail plate 3 provided with a partial skin plate), erectors 44a and 44b for constructing an inner wall body by assembling segments S on the inner periphery of each of the plurality of skin plates 31, and a skin plate having the same cross-sectional shape as the skin plate 21 41 (middle body part skin plate), and a middle body part 4 for connecting the front body part 2 and the tail part 3 to each other.
With this configuration, the thickness of the skin plate 31 can be reduced by dividing the tail portion 3 compared to the case where the tail body 3 is configured with the same cross-sectional shape as the front body portion 2. Thereby, even if the shield machine 1 is enlarged and the cross-sectional area of the non-circular tunnel excavated at one time is increased, the tail void can be reduced and the amount of backfill injection can be reduced.

Further, in the present embodiment, the cross section of the skin plate 21 is rectangular, and the plurality of skin plates 31 have a plurality of divided regions obtained by dividing the longitudinal direction of the cross section of the skin plate 21 as the respective cross sectional shapes.
With this configuration, the stress and deflection amount of the skin plate 31 due to external force can be reduced.

Further, in the present embodiment, a plurality of shield jacks 43 that obtain reaction force from the existing segment S at the time of propulsion are attached to the inner periphery of the skin plate 41, and the reinforcement spanned inside the skin plate 41 is provided. The column 45 is attached with segment pressing jacks 46a and 46b for pressing the existing segment S during propulsion.
With this configuration, it is possible to prevent deviation of the existing segment S during propulsion.

  Note that the present invention is not limited to the above-described embodiments, and it is obvious that the embodiments can be appropriately changed within the scope of the technical idea of the present invention.

DESCRIPTION OF SYMBOLS 1 Shield machine 2 Front trunk | drum 3 Tail part 4 Middle trunk | drum 21 Skin plate 22 Cutter drum 23 Bulkhead 24 Chamber 3a 1st division | segmentation tail part 3b 2nd division | segmentation tail part 31 Skin plate 32 Recessed part 33 Plate-shaped member 41 Skin plate 42 Ring Garter 43 Shield jacks 44a, 44b Elector 45 Reinforcing pillars 46a, 46b Segment holding jack S Segment

Claims (3)

A shield machine for digging a non-circular tunnel,
A front body part having a cylindrical front body skin plate having substantially the same cross-sectional shape as the non-circular tunnel, and a front body part for excavating the face with a cutter drum disposed at the front end;
A tail portion including a plurality of tail skin plates each having a plurality of divided regions obtained by dividing a cross section of the front body skin plate;
An erector that constructs an inner wall body by assembling segments on the inner periphery of each of the plurality of tail skin plates;
A shield machine comprising an intermediate body skin plate having the same cross-sectional shape as the front body skin plate, and comprising an intermediate body part that connects the front body part and the tail part. The cross section of the front torso skin plate is rectangular,
2. The shield machine according to claim 1, wherein the plurality of tail skin plates have a plurality of divided regions obtained by dividing a longitudinal direction of a cross section of the front body skin plate, respectively.   A plurality of shield jacks that obtain reaction force from the existing segments during propulsion are attached to the inner periphery of the middle torso skin plate. 3. A shield machine according to claim 1, further comprising a segment pressing jack for pressing an existing segment during propulsion.

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