JP2010189988A - Shield machine and method of constructing tunnel with rectangular cross section - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shield machine that can excavate a tunnel with a substantially rectangular cross section in a forward earth with only a pair of cutters and that is prevented from being rolled, and a method of constructing the tunnel with a rectangular cross section using the shield machine. <P>SOLUTION: The excavating range of the shield machine 1 is divided into two parts at the general center of the shield machine 1. An excavation part is provided to each of the divided excavation ranges (right and left half ranges of the shield machine 1). A rotating body 21a the rotating axis 33a of which is at the generally center of the excavating range is provided to one excavating range. A frame 25a is joined to the rotating body 21a. The frame 25a extends in the radial direction of the rotating body 21a, and a cutter 29a is provided to the end thereof. A same excavating part is provided also to the other excavation range. Namely, a pair of excavation parts are provided to the shield machine. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a shield machine capable of excavating a tunnel having a substantially rectangular cross-sectional shape and having a constricted portion directed inward at a substantially central position of upper and lower surfaces, and a method for constructing a rectangular cross-sectional tunnel using the shield machine.

  Many conventional excavators excavate natural ground in front of the excavator by the rotation of a substantially circular cutter facing the excavation direction. In this case, the tunnel has a circular cross-sectional shape. On the other hand, an excavator capable of excavating a rectangular cross-section tunnel using a plurality of cutters has been developed.

  As a shield machine capable of excavating a tunnel having such a rectangular shape and a cross-sectional shape, for example, a main cutter is provided on the front surface of the shield machine body, and a planetary cutter that can be displaced in the radial direction of a rotating body that rotates integrally with the main cutter. There is a free section shield machine that controls the revolution orbit of the planetary cutter by a control unit and excavates a portion that cannot be excavated by the main cutter by the operation of the planetary cutter (Patent Document 1).

  In addition, a center cutter is provided on the front surface of the shield machine, and there is provided a guide member that has a rotating member and a planetary cutter provided on the rotating member at a position away from the rotating body of the center cutter, and regulates the orbit of the planetary cutter. There is a free section shield machine (patent document 2).

JP 2001-140585 A Japanese Patent Laid-Open No. 2-311692

  However, in the shield machine described in Patent Document 1 and Patent Document 2, it is necessary to provide a main cutter for excavating a front ground in front of the shield machine. For example, when excavating a rectangular cross section, excavation at the four corners of a tunnel excavated in a circle by the main cutter is performed by a planetary cutter provided as an auxiliary. For this reason, a planetary cutter is required in addition to the main cutter, and a plurality of shapes of cutters are required.

  Further, both of the shield machines of Patent Document 1 and Patent Document 2 excavate the four corners of a rectangular shape with a planetary cutter, and are assumed to have a constricted portion at a part of the rectangular horizontal center. Not. In this case, in the shield machine of patent documents 1 and 2, since it is necessary to reduce the size of the main cutter, it is necessary to increase the amount of excavation by the planetary cutter. For this reason, there exists a problem that the apparatus which needs to enlarge a planetary cutter enlarges.

  The present invention has been made in view of such a problem, and a shield machine capable of excavating a substantially rectangular cross-section tunnel with a pair of cutters only in front of the ground, and capable of preventing rolling of the shield machine and the like. An object of the present invention is to provide a method for constructing a rectangular cross-section tunnel using the.

  A first invention for achieving the above-described object is a shield machine for excavating a natural ground, which is a shield machine main body having a substantially rectangular cross-sectional shape, a jack for propelling the shield machine main body, and the front of the shield machine main body. And a pair of excavation sections provided in each excavation range, the pair of excavation sections each having a rotating body whose rotation axis is substantially the center of the excavation range, and a front surface of the rotating body. A frame provided in a direction substantially perpendicular to the rotation axis of the rotating body, and having one end rotatably disposed at a position eccentric from the rotation axis of the rotating body, and the other end of the frame And a rotary cutter having a plurality of blades, respectively, and the front surface of the shield machine main body can be excavated only by the rotary cutter.

  It is preferable that an opening that is wider than the frame and communicates with a hole for discharging excavated earth and sand is provided below each of the halved excavation ranges.

  The rotary cutter is provided around a front excavation part for excavating a front surface of the shield machine in the traveling direction, which is a surface substantially perpendicular to the rotation axis of the rotary cutter, and the front surface of the shield machine in the traveling direction is approximately A side excavation part excavating a vertical surface, and the shield machine traveling direction excavated by the front excavation part and the arrangement direction of the blades provided in the side excavation part have a predetermined angle Is desirable.

  According to the shield machine of the first invention, the excavation part is composed of a rotating body, a frame provided on the rotating body, and a rotary cutter provided on the frame, and the front surface of the shield machine is divided into two and divided into two. Since the pair of excavating portions capable of excavating the slab is provided, the rotary cutter is movable with respect to the entire excavation surface, and the natural ground in front of the shield machine can be excavated into a substantially rectangular cross-sectional shape only by the pair of cutters.

  Moreover, if a hole connected to the screw conveyor for discharging excavated sediment is provided below each of the two excavation ranges, and an opening wider than the frame width is provided in front of the hole, the movement position of the cutter Therefore, the hole is not blocked by the frame and the cutter. Therefore, it is possible to discharge excavated earth and sand reliably regardless of the cutter position.

  In addition, if the rotary cutter is provided with a front excavation part for excavating the front of the shield machine and a side excavation part for excavating a surface direction substantially perpendicular to the front surface of the shield machine, the traveling direction of the shield machine to which the rotary cutter is attached Then, it is possible to excavate both directions substantially perpendicular to the traveling direction.

  A second invention is a method of constructing a substantially rectangular cross-section tunnel using the shield machine according to the first invention, and the rotation of the rotary cutter around the rotation axis of the rotary body as seen from the front of the shield machine. A method for constructing a substantially rectangular cross-section tunnel, characterized in that a moving direction is a reverse rotation to the rotating direction of the rotating cutter.

  The rotation directions of the pair of rotating bodies may be opposite to each other, and the rotation directions of the pair of rotation cutters may be opposite to each other.

  The plurality of blades provided in the pair of rotating cutters may all be oriented in the same circumferential direction, and the rotating cutter may rotate only in one direction.

  A part of the excavation range allows excavation to the extent that the rotary cutter protrudes from the outer periphery of the shield machine main body to a predetermined amount, and the other part of the excavation range is only from the outer periphery of the shield machine main body to the predetermined amount inside. Excavation may be performed.

  Here, excavating to the extent that it protrudes refers to a case where a part of the cutter is excavated from the outer periphery with respect to the projected external shape viewed from the front of the shield machine (hereinafter referred to as “extruded excavation”). Excavation only from the outer circumference to a predetermined amount inside means that the cutter excavates only from the outer circumference of the shield machine to the inner side (that is, the cutter is hidden in the projected outline of the shield machine) (hereinafter, minus side) Called drilling).

  According to the second aspect of the present invention, it is possible to excavate a substantially rectangular cross-section tunnel, and the rotary cutter in a direction substantially perpendicular to the excavation direction of the shield machine around the rotation axis of the rotary body as viewed from the front of the shield machine. Therefore, the rotation of the shield machine due to the movement of each rotary cutter is canceled out by the rotation of the rotary cutter, so that the shield machine can be prevented from rolling.

  Further, in the pair of excavation ranges, when the moving direction of the rotary cutter in the direction substantially perpendicular to the digging direction of the shield machine around the rotation axis of the rotary body as seen from the front of the shield machine is opposite to each other, The rotations of the shield machines due to the movement of the rotary cutter cancel each other. For this reason, rolling of the shield machine can be prevented. Further, if the rotation directions of the pair of rotary cutters are opposite to each other, rolling of the shield machine can be more effectively prevented.

  In addition, since the excavation range of the cutter can be changed to overhang excavation and minus side excavation, the attitude and traveling direction of the shield machine can be easily controlled.

  According to the present invention, there is provided a shield machine capable of excavating a substantially rectangular cross-section tunnel in front of a natural ground only by a pair of cutters, and preventing rolling of the shield machine, and a method for constructing a rectangular cross-section tunnel using the shield machine. Can be provided.

1 is a side sectional view showing a shield machine 1. FIG. The front view of the shield machine 1. FIG. The figure which shows operation | movement of the rotary body 21, the frame 25, and the cutter 29 in the shield machine 1. FIG. The figure which shows the moving direction and rotation direction of the cutter 29. FIG. The figure which shows the excavation range by the cutter 29. FIG. It is a figure which shows the cutter 29, (a) is a front view, (b) is a H direction arrow line view of (a). The figure which shows the side surface of the spoke 43, and is a figure which shows the arrangement | positioning angle of the blade 39. FIG. (A) is a figure which shows the state excavated to the range which the cutter 9 protruded with respect to the outer periphery of the shield machine 1, (b) is a figure which shows the state which the cutter 9 excavated to the minus side. The figure which shows the control method of the excavation range ahead of the shield machine 1 in the state which the shield machine 1 rolled. The figure which shows the control method of the excavation range ahead of the shield machine 1 in the case of changing the course of the shield machine 1.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 and 2 are diagrams showing a shield machine 1 according to the present invention. 1 is a side sectional view in the vicinity of the cutter 29a in FIG. As shown in FIG. 1, the shield machine 1 is mainly composed of a shield machine body composed of a skin plate 3, a partition wall 5, a screw conveyor 15, etc., and a hydraulic jack 7 that is a shield jack for propelling the shield, The excavator includes a cutter 29a for excavating a natural ground in front of the shield, a frame 25a, a rotating body 21a, and the like.

  The shield machine 1 has a cylindrical skin plate 3 having a substantially rectangular cross-sectional shape, and a cylindrical tail plate 9 is connected to the rear of the skin plate 3. A hydraulic jack 7 is provided inside the skin plate 3. A segment 11 assembled by a segment assembling apparatus (not shown) is installed in the tail plate 9. The segment 11 and the tail plate 9 are sealed with a tail seal 13.

  The hydraulic jack 7 can reciprocate in the axial direction. The shield machine 1 presses the segment 11 with the hydraulic jack 7 and propels it forward by the reaction force from the segment 11.

  A partition wall 5 is provided in front of the skin plate 3. The partition wall 5 partitions the side where the hydraulic jack 7 and the like are provided and the side where the cutter 29a and the like which will be described later are provided (the chamber 19 side). Below the partition wall 5, openings 17a and 17b (FIG. 2) are provided. The openings 17a and 17b communicate with the rear screw conveyors 15a and 15b, respectively. That is, the openings 17a and 17b that open toward the front of the partition wall 5 are provided with holes that communicate with the screw conveyors 15a and 15b at the rear. The excavated earth and sand in the chamber 19 excavated by the excavating part is taken into the openings 17a and 17b while maintaining a predetermined pressure, and discharged backward by the screw conveyors 15a and 15b.

  The partition 5 is provided with rotating bodies 21a and 21b (FIG. 2). The rotating bodies 21a and 21b can be rotated by the motor 23 around the rotating body rotating shafts 33a and 33b.

  A frame 25a is provided on the front surface of the rotating body 21a. The frame 25a is provided in an arm shape in a direction substantially perpendicular to the rotating body rotation shaft 33a of the rotating body 21a. The rotating body 21a is provided with a frame motor 27a for rotating the frame 25a, and the frame 25a is rotatable around a frame rotation shaft 35a. The frame rotation shaft 35a is eccentric with respect to the rotating body rotation shaft 33a (that is, located at a shifted position). That is, one end of the frame 25a is joined to the rotating body 21a so as to be rotatable about the frame rotating shaft 35a, and the frame 25a can be rotated on a rotating shaft different from the rotating body 21a. .

  A cutter 29a having a plurality of blades is provided in the vicinity of the end of the frame 25a opposite to the joint with the rotating body 21a. The cutter 29a is a part for excavating natural ground. The frame 25a is provided with a cutter motor 31a, and the cutter 29a is rotatable around a cutter rotating shaft 37a. Note that the cutter rotating shaft 37a is eccentric (that is, located at a shifted position) with respect to the frame rotating shaft 35a and the rotating body rotating shaft 33a. The rotating body 21b has the same configuration.

  FIG. 2 shows a front view of the shield machine 1. Skin plate 3 having a substantially rectangular cross-sectional shape forms the outer periphery of shield machine 1. The shield machine 1 is provided with constricted portions 4a and 4b at substantially central positions on the upper and lower surfaces. In other words, the outer shape of the shield machine 1 is a substantially rectangular cross section having a constricted part constricted inward of the shield machine 1 at the upper and lower approximate centers.

  The excavation range of the shield machine 1 is divided into two at the approximate center of the shield machine 1 (line connecting the constricted portions 4a and 4b). In FIG. 2, it is divided into left and right by a line connecting the constricted portions 4a and 4b. Excavations are provided in each of the two excavation ranges (the left and right half ranges of the shield machine 1).

  In one excavation range (for example, the left half of FIG. 2), a rotating body 21a having a rotating body rotation shaft 33a at the approximate center of the excavation range is provided. A frame 25a is joined to the rotating body 21a. The frame 25a extends toward the radial direction of the rotating body 21a, and a cutter 29a is provided at the end. A plurality of blades 39 are provided on the cutter 29a. A stirring blade 41a is provided on the opposite side of the frame 25a from the joint with the cutter 29a. The agitating blade 41a agitates the earth and sand in the chamber 19 (FIG. 1) to prevent caking and blockage of the earth and sand.

  Here, the rotating body 21a can rotate in the reciprocating direction around the rotating body rotating shaft 33a (in the directions of arrows A1 and B1 in the figure). The frame 25a can reciprocate around the frame rotation shaft 35a (in the directions of arrows C1 and D1 in the figure). The cutter 29a rotates in one direction around the cutter rotation shaft 37a (for example, in the direction of arrow E1 in the figure). That is, the cutter 29a always rotates in the same direction and excavates natural ground. For this reason, the blade 39 provided in the cutter 29a is provided in one direction (the same circumferential direction with respect to the rotation direction).

  The same excavation part as the left excavation range is also provided in the excavation range on the other side (for example, the right half of FIG. 2). The configuration of the right excavation unit is the same as the configuration of the left excavation unit, and a description thereof will be omitted.

  Next, operation | movement of the excavation part of the shield machine 1 is demonstrated. FIG. 3 is a view showing the excavation part operation of the shield machine 1.

  First, from the position of FIG. 3 (a) toward the shield machine 1 (as viewed from the front of the drawing), the cutter 29a moves counterclockwise about the rotating body rotating shaft 33a, and the cutter 29b moves the rotating body rotating shaft 33b. An example of moving clockwise around the center will be described. In the position of FIG. 3A, the cutter 29b is excavating near the corner of the rectangular cross section, and the cutter 29b excavates the position farthest from the center (rotary body rotating shaft 33). Therefore, for example, the rotating body rotating shaft 33b, the frame rotating shaft 35b, and the cutter rotating shaft 37b are positioned so as to be aligned on a straight line. The cutter 29b moves from this position to the excavation range in the tunnel lower surface direction.

  In order to move the position of the cutter 29b from this state, the frame 25b is rotated counterclockwise (arrow C2 direction in the figure) while rotating the rotating body 21b clockwise (arrow B2 direction in the figure). Hereinafter, the cutter 29b performs excavation while always rotating in a certain direction (for example, counterclockwise in the direction of arrow E2 in the figure).

  Similarly, the cutter 29a excavates near the constricted portion 4a and moves to the excavation range on the upper surface of the tunnel. In order to move the position of the cutter 29a from this state, the frame 25a is rotated clockwise (arrow D1 direction in the figure) while rotating the rotating body 21a counterclockwise (arrow A1 direction in the figure). Hereinafter, the cutter 29a performs excavation while always rotating in a certain direction (for example, clockwise in the direction of arrow E1 in the figure).

  FIG. 3B shows a state in which the positions of the cutters 29a and 29b have moved in this way. When the cutter 29a comes near the corner of the rectangular cross section, the rotation direction of the rotating body 21a is reversed clockwise (in the direction of arrow B1 in the figure) and the rotation direction of the frame 25a is counterclockwise (in the direction of arrow C1 in the figure). Reverse. Similarly, with respect to the cutter 29b, the rotation direction of the rotating body 21b is reversed counterclockwise (arrow A2 direction in the figure), and the rotation direction of the frame 25b is reversed clockwise (arrow D2 direction in the figure).

  Further, when the cutter 29a passes near the corner of the rectangular cross section, as shown in FIG. 3C, the rotating direction of the rotating body 21a is reversed counterclockwise (in the direction of arrow A1 in the figure), and the frame 25a The direction of rotation is reversed clockwise (in the direction of arrow D1 in the figure). Similarly, with respect to the cutter 29b, the rotation direction of the rotating body 21b is reversed clockwise (in the direction of arrow B2 in the figure), and the rotation direction of the frame 25b is reversed counterclockwise (in the direction of arrow C2 in the figure).

  Thereafter, similarly, the cutters 29a and 29b are moved along the outer periphery of the rectangular cross section. The above operation is repeated to excavate the ground in front of the shield machine 1 while moving the cutters 29a and 29b within the respective excavation ranges.

  Even when the frames 25a, 25b and the cutters 29a, 29b pass in front of the openings 17a, 17b (FIG. 2), the openings 17a, 17b are larger than the widths of the frames 25a, 25b. The openings 17a and 17b are not completely blocked by 25b. For this reason, there is no problem in discharging excavated earth and sand regardless of the positions of the cutters 29a and 29b.

  FIG. 4 is a diagram showing the movement direction of the cutters 29a and 29b and the rotation direction of the cutters 29a and 29b when viewed from the front of the shield machine 1. As shown in FIG. For example, the shield machine 1 excavates the excavation range in the left half of the shield machine 1 while the cutter 29a moves counterclockwise around the rotating body rotation shaft 33a. That is, the cutter 29a excavates the natural ground while moving in a direction substantially perpendicular to the excavation direction of the shield machine 1. At this time, the cutter 29a rotates clockwise around the cutter rotation shaft 37a. Therefore, the rotating direction of the cutter 29a and the moving direction (the rotating direction around the rotating body rotating shaft 33a) of the cutter 29a within the excavation range are opposite to each other.

  On the other hand, the cutter 29b excavates the excavation range of the right half of the shield machine 1 while moving clockwise around the rotating body rotation shaft 33b. That is, the cutter 29b excavates the natural ground while moving in a direction substantially perpendicular to the excavation direction of the shield machine 1. At this time, the cutter 29b rotates counterclockwise around the cutter rotation shaft 37b. Therefore, the rotating direction of the cutter 29b and the moving direction (the rotating direction around the rotating body rotating shaft 33b) within the excavation range of the cutter 29b are opposite to each other. Further, the rotation direction of the cutter 29a around the rotary body rotation shaft 33a and the rotation direction of the cutter 29b around the rotary body rotation shaft 33b are also reverse rotations. For this reason, the force of the rolling direction which generate | occur | produces in the shield machine 1 accompanying excavation cancels, and rolling can be prevented. Therefore, since it is not necessary to rotate the cutter in the normal and reverse directions as in a normal rolling measure, the cutters 29a and 29b need only always rotate in a certain direction.

  FIG. 5 is a diagram showing a cutter locus 40 which is a movement locus of the cutters 29a and 29b. As shown in FIG. 5, the cutters 29 a and 29 b can excavate the entire range of the excavation section 42. That is, the shield machine 1 can excavate the natural ground ahead of the shield machine 1 into a substantially rectangular cross section only by the pair of cutters 29a and 29b.

  In addition, according to this shield machine 1, not only the above-mentioned rectangular cross section but the tunnel of various cross-sectional shapes can also be excavated.

  Next, the cutters 29a and 29b will be described. In the following description, the cutters 29a and 29b have the same configuration, and therefore will be described as the cutter 29 unless otherwise specified. 6A and 6B are diagrams illustrating the cutter 29, in which FIG. 6A is a front view, FIG. 6B is a side view of the spoke 43, and is a view taken in the direction of arrow H in FIG. The cutter 29 is provided with spokes 43 radially about the cutter rotation shaft 37. The spoke 43 is a member having a substantially rectangular cross section.

  A plurality of blades 39 are provided on the front surface of the spoke 43. As shown in FIG. 6A, the cutter 29 rotates, for example, in one direction of the arrow F. Therefore, all the blades 39 provided on the spokes 43 of the cutter 29 are provided in the same circumferential direction (direction of arrow G in the drawing). By setting the rotation direction of the cutter 29 to one direction, it is not necessary to install the blade 39 toward both sides (both rotation directions), so that the resistance during excavation by the cutter 29 can be reduced. As described above, since the cutter 29a and the cutter 29b rotate in opposite directions, the directions of the blades 39 are opposite to each other. For example, when the cutter 29a rotates in the F direction, the cutter 29b rotates in the opposite direction to the F direction, and the blade 39 of the cutter 29b may be provided in the opposite direction to the G direction.

  As shown in FIG. 6 (b), the spoke 43 is provided with a front excavation part 47 on the rotation inner peripheral side and a side excavation part 45 on the rotation outer peripheral side. The front excavation part 47 is disposed toward the front of the cutter 29 (the traveling direction of the shield machine 1). On the other hand, the side excavation part 45 is arranged with a slight inclination in the cutter radial direction with respect to the traveling direction of the shield machine 1.

  The front excavation unit 47 is a part that excavates natural ground mainly with respect to the front of the cutter 29 (the front surface in the traveling direction of the shield machine 1). The side excavation part 45 is a part which excavates a natural ground mainly with respect to the side of the cutter 29 (direction substantially perpendicular to the traveling direction of the shield machine 1).

  That is, as described above, the cutter 29 moves in a plane substantially perpendicular to the traveling direction of the shield machine 1 by the rotating operation of the rotating body 21 and the frame 25. The side excavation unit 45 is a part that excavates natural ground in the moving direction of the cutter 29.

  On the side surface of the spoke 43 (the side surface in the direction in which the cutter 29 rotates), a mud additive inlet 49 is provided. Usually, since the cutter used for a shield machine excavates a natural ground with respect to the front surface of the shield machine in the traveling direction, the mud filler inlet is installed toward the front of the cutter. On the other hand, since the cutter 29 of the present invention mainly performs excavation in the moving direction of the cutter 29 (side of the cutter 29) by the side excavation portion 45, the cutter 29 is added to the side surface of the spoke 43 that is the excavation direction of the cutter 29. It is desirable to provide a mud injection port 49.

  FIG. 7 is a diagram showing a state in which the natural ground 53 is excavated by the cutter 29, and is a diagram showing the arrangement and direction of the blade 39. An arrow I in the figure is in front of the cutter 29 and indicates the traveling direction of the shield machine 1. The blades 39 of the front excavation unit 47 are arranged with a blade interval 55a. The installation direction of the blade 39 of the front excavation unit 47 coincides with the traveling direction of the shield machine 1. That is, the blade 39 of the front excavation unit 47 excavates the ground 53 in front of the shield machine 1 in the traveling direction.

  In the side excavation part 45, the spoke 43 is tapered with a predetermined angle with respect to the front excavation part 47 in two stages. In the side excavation part 45, the blade 39 is provided to be inclined in the radial direction of the cutter 29 according to the taper. For example, an angle of about 20 degrees is provided at the outer peripheral position of the front excavation portion 47, and a taper portion having an angle of about 45 degrees is provided on the outer periphery. Furthermore, a surface substantially perpendicular to the traveling direction of the shield machine 1 is formed on the outermost periphery. Therefore, in this case, the installation direction of the blade 39 at each position is such that the blade angle 51a is 20 degrees, the blade angle 51b is 45 degrees, and the blade angle 51c is 90 degrees with respect to the traveling direction of the shield machine 1.

  Further, the blade interval 55 b of the blade 39 in the side excavation unit 45 is narrower than the blade interval 55 a in the front excavation unit 47. That is, the installation density of the blades 39 is large in the side excavation part 45. This is because the cutter 29 is mainly excavated in the side of the cutter rather than excavated in the forward direction of the cutter.

  The shape of the cutter 29 is not limited to the example shown in FIG. The taper shape of the side excavation part 45 may be other than two stages, and the angle is not limited. However, in order to excavate the cutter side efficiently, the side excavation part desirably has an angle of about 20 to 90 degrees, and more desirably, an angle of at least about 45 to 90 degrees is formed on the outer periphery of the cutter. It is desirable that

  FIG. 8 is a diagram illustrating a state in which excavation is performed by changing the excavation range of the cutters 29 a and 29 b of the shield machine 1. By controlling the rotation angles of the rotating bodies 21a and 21b and the frames 25a and 25b, a part of the cutters 29a and 29b is protruded outside the outer periphery of the shield machine 1 (that is, the outer periphery formed by the skin plate 3). Can do. FIG. 8 shows an example in which a part of the cutter 29a protrudes from the shield machine 1 by the protruding excavation amount F.

  Similarly, a part of the cutters 29 a and 29 b can be positioned inside the outer periphery of the shield machine 1. FIG. 8 shows an example in which a part of the cutter 29b is arranged on the minus side by the minus side excavation amount G from the shield machine 1.

  Note that the protruding excavation amount means the protruding length of the cutter 29 from the outer peripheral portion of the projected outer shape of the shield machine 1 during the protruding excavation. Similarly, the minus side excavation amount means the length from the outer periphery of the projected outer shape of the shield machine 1 to the outermost excavation range by the cutter 29 during the minus side excavation.

  Next, control of the shield machine 1 will be described. FIG. 9 shows a method of correcting the rolling of the shield machine 1 by changing the excavation range of the cutters 29a and 29b.

  When rolling occurs in the shield machine 1 itself and the shield machine 1 is displaced from the horizontal state, the excavation range of the cutters 29a and 29b is controlled to change the excavation range. For example, as shown in FIG. 9A, when the shield machine 1 rolls from the regular excavation section 57, the excavation range of the cutters 29a, 29b (the cutters 29a, 29b in the direction perpendicular to the excavation direction of the shield machine 1) The movement range is changed, and control is performed so that the regular excavation section 57 is obtained.

  In this case, for example, the extra excavation part 59 which is a part where the regular excavation cross section 57 comes to the outside of the outer periphery of the shield machine 1 protrudes the cutters 29a and 29b from the shield machine 1 like the cutter 29a of FIG. To move.

  Similarly, the minus digging portion 61, which is the portion where the regular excavation cross section 57 comes to the inner side than the outer periphery of the shield machine 1, has the cutters 29a and 29b on the minus side from the shield machine 1 like the cutter 29b of FIG. Move to come.

  By doing in this way, the regular excavation cross section 57 can be excavated irrespective of the outer peripheral shape of the shield machine 1. In addition, if such control is performed in a state where the rolling angle of the shield machine 1 is small, the shield machine 1 tends to fall within the excavation section, and eventually falls within the regular excavation section 57. That is, the rolling of the shield machine 1 can be corrected.

  FIG. 10 is a diagram illustrating a method of controlling the traveling direction of the shield machine 1 by the same control method. For example, as shown in FIG. 10 (a), when a deviation occurs in the traveling direction of the shielding machine 1 with respect to the traveling direction of the shielding machine 1 (arrow G in the figure), the shielding machine 1 proceeds normally. The excavation range on the side to be advanced may be set as the extra digging portion 59 and the opposite side to the side to be advanced may be set as the minus digging portion 61 so as to be in the direction.

  By doing in this way, since the shield machine 1 tends to be within the excavation cross section, the traveling direction of the shield machine 1 can be controlled so as to be in the normal direction.

  Such control is performed by detecting the posture and direction by various sensors provided in the shield machine 1, and automatically setting the excavation range by the computer provided in the shield machine 1, and the cutter 29a, You may control operation | movement of the rotary bodies 21a and 21b and the flame | frames 25a and 25b so that 29b can move the excavation range. The positions of the cutters 29a and 29b, the rotation angles of the frames 25a and 25b, and the rotating bodies 21a and 21b are grasped by a tachometer or the like.

  Moreover, the detection part which can detect the soil quality of earth and sand is provided in the front surface of the shield machine 1, and the excavation range may be controlled according to the soil quality. For example, when excavating soft soil, the amount of overhang or minus moat of the cutters 29a and 29b is reduced, and when excavating hard soil, the amount of overhang or minus minus of the cutters 29a and 29b is reduced. You may increase. When the shield machine 1 is excavated and the excavation range is changed according to the soil quality at the excavation position, collapse of the excavation surface and excessive excavation can be prevented, and excavation can be performed efficiently.

  As the soil detection, a detector for detecting the flow resistance or the like in the chamber of the excavated soil may be provided, or the soil may be detected by the motor current of the cutters 29a and 29b.

  As described above, according to the shield machine 1 according to the embodiment of the present invention, the front surface of the shield machine is divided into two parts, and a pair of excavation parts capable of excavating each of the two excavation ranges is provided. Since the excavation part is composed of the rotating bodies 21a and 21b, the frames 25a and 25b provided on the rotating bodies 21a and 21b, and the cutters 29a and 29b provided on the frames 25a and 25b, the pair of cutters 29a and 29b move with respect to the entire excavation surface. It is possible, and the natural ground ahead of the shield machine 1 can be excavated into a substantially rectangular cross-sectional shape with only a pair of cutters.

  In particular, the cutters 29a and 29b are provided with a front excavation portion 45 for excavating the front of the shield machine 1 and a side excavation portion 47 for excavating a surface direction substantially perpendicular to the front surface of the shield machine. It is possible to excavate in a direction substantially perpendicular to the traveling direction.

  Moreover, according to the shield machine 1, since a tunnel having a substantially rectangular cross section having a constricted portion can be easily excavated, a minimum necessary tunnel cross section can be obtained with a smaller excavation amount than a normal rectangular cross section tunnel. In addition, a tunnel having high strength can be obtained by the arch effect against the earth pressure from above.

  In addition, holes connected to the screw conveyors 15a and 15b for discharging excavated earth and sand are provided below each of the two excavated areas, and openings 17a and 17b wider than the widths of the frames 25a and 25b are provided in front of the holes. Since they are provided, the holes are not blocked by the frame frames 25a and 25b and the cutters 29a and 29b depending on the moving positions of the cutters 29a and 29b. Therefore, it is possible to discharge excavated earth and sand reliably regardless of the cutter position.

  Further, since the frames 25a and 25b are provided with the stirring blades 41a and 41b, the excavated earth and sand are stirred in the chamber 19 of the shield machine 1 by the rotating operation of the frames 25a and 25b accompanying the movement of the cutters 29a and 29b. , Sediment consolidation and blockage can be prevented.

  Further, since the rotation directions of the pair of rotating bodies 21a and 21b are opposite to each other, when viewed from the front of the shielding machine 1, the rotation direction of the shielding machine 1 around the rotating body rotation shafts 33a and 33b is substantially perpendicular. The movement directions of the cutters 29a and 29b in the opposite directions are opposite to each other. For this reason, the rolling of the shield machine 1 due to the movement of the cutters 29a and 29b is canceled. Therefore, rolling of the shield machine 1 can be prevented. Furthermore, if the rotation directions of the pair of cutters 29a and 29b are opposite to each other, rolling of the shield machine 1 can be more effectively prevented.

  In addition, since the excavation range of the cutters 29a and 29b can be changed to overhang excavation and minus side excavation, the attitude of the shield machine can be easily controlled.

  For example, even when the shield machine 1 is rolling, the attitude of the shield machine 1 can be easily controlled by setting the excavation range of the cutters 29a and 29b to the normal excavation section 57 regardless of the attitude of the shield machine 1. be able to. Similarly, if the advancing direction is set as the outflow excavation and the opposite side is the negative excavation, the advancing direction of the shield machine 1 can be easily controlled. Moreover, if the excavation range can be changed according to the soil quality, it is possible to prevent the excavation surface from collapsing and excessive excavation.

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

  For example, the rotation direction and the movement direction of the cutters 29a and 29b are not limited to the embodiment. The cutters 29a and 29b may be rotated and moved in the direction opposite to that shown in FIG.

1 ......... Shielding machine 3 ......... Skin plate 5 ......... Partition wall 7 ......... Hydraulic jack 9 ......... Tail plate 11 ......... Segment 13 ......... Tail seals 15a, 15b ......... Screw conveyor 17a, 17b ......... Opening 19 ......... Chamber 21a, 21b ......... Rotating body 23a, 23b ......... Rotating body motor 25a, 25b ......... Frame 27a, 27b ......... Frame motor 29a, 29b ......... Cutter 31a, 31b ......... Cutter motors 33a, 33b ......... Rotating body rotating shafts 35a, 35b ......... Frame rotating shafts 37a, 37b ......... Cutter rotating shafts 39 ......... Blade 40 ......... Cutter loci 41a, 41b ……… Stirring blade 42 ……… Drilling cross section 43 ……… Spoke 45 ……… Side excavation part 47 ……… Front excavation part 49 ……… Addition of mud 51a, 51b, 51c ......... blade angle 53 ......... natural ground 55a, 55b ......... edge spacing 57 ......... normal drilling section 59 ......... extra digging portion 61 ......... minus digging unit

Claims (6)

It is a shield machine that digs the ground,
A shield machine body having a substantially rectangular cross-sectional shape;
A jack for propelling the shield machine body;
A pair of excavating parts provided in each excavation range, the front of the shield machine main body being divided into two;
Have
The pair of excavation parts is
Rotating bodies each having an approximate center of the excavation range as a rotation axis;
A frame provided on a front surface of the rotating body in a direction substantially perpendicular to a rotation axis of the rotating body, and having one end rotatably arranged at a position eccentric from the rotation axis of the rotating body;
A rotary cutter provided at the other end of the frame and having a plurality of blades;
Each with
A shield machine characterized in that the front surface of the shield machine main body can be excavated only by the rotary cutter.   The shield machine according to claim 1, wherein an opening that is wider than the frame and communicates with a hole for discharging excavated earth and sand is provided below each of the divided excavation ranges. The rotating cutter is
A front excavation unit excavating a shield machine traveling direction front surface which is a surface substantially perpendicular to a rotation axis of the rotary cutter;
A side excavation unit that is provided around the front excavation unit and excavates a surface substantially perpendicular to the front surface of the shield machine in the traveling direction;
Have
The shield machine according to claim 1 or 2, wherein the shield machine traveling direction excavated by the front excavation part and the arrangement direction of blades provided in the side excavation part have a predetermined angle. A method for constructing a substantially rectangular cross-section tunnel using the shield machine according to claim 1,
A method for constructing a substantially rectangular cross-section tunnel, characterized in that the rotational movement direction of the rotary cutter around the rotational axis of the rotary body is opposite to the rotational direction of the rotary cutter when viewed from the front of the shield machine.   5. The construction of a substantially rectangular cross-section tunnel according to claim 4, wherein the rotation directions of the pair of rotating bodies are opposite to each other and the rotation directions of the pair of rotation cutters are opposite to each other. Method. A part of the excavation range allows the rotary cutter to excavate to a range that protrudes a predetermined amount from the outer periphery of the shield machine body,
The method for constructing a substantially rectangular cross-section tunnel according to claim 4 or 5, wherein the other part of the rotary cutter allows excavation only from the outer periphery of the shield machine main body to a predetermined amount inside.

Images