JP3245388B2 - Tunnel support material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel supporter for supporting an inner wall of a tunnel excavated by a tunnel excavator.

[0002]

2. Description of the Related Art Conventionally, in order to support a portion of a tunnel excavated by a tunnel excavator which is easily collapsed, a ring-shaped steel support and a horizontal sheet pile are generally combined. However, in this method, the supporter is assembled behind the tunnel excavator (the wellhead side) so that the tunnel excavator does not cause any adverse effect when the reaction force is applied to the ground. Time has passed.

Therefore, recently, a tunnel excavator 1 as shown in FIGS.
A method of assembling a ring-shaped support material by assembling a ring-shaped support material with the tail portion 2 has been proposed. In the method of assembling the ring-shaped support material, a ring-shaped support material 3 having a predetermined width in the tunnel axial direction is assembled in the tail portion 2 of the tunnel excavator 1. Then, it is pushed out from the tail portion 2 to a rear support point by a jack device (not shown) or the like, and the inner wall of the tunnel is supported as soon as possible. The ring-shaped support member 3 is a piece 3 divided in the circumferential direction.
It is composed of a. And each piece 3a
Has a frame composed of two arcuate grooved steels arranged in parallel and a plurality of linear shaped steels connecting between the arcuate grooved steels. A fall prevention member such as a wire mesh, expanded metal, or a grid-like angle is attached to the tunnel wall surface side in the frame.

When assembling the piece 3a in the tail portion 2 of the tunnel excavator 1, the pieces 3a are assembled in the following procedure in order to increase the efficiency and speed of the assembling operation. (1) The first piece 3a is gripped by the erector head 5 that rotates along the erector ring 4 provided in the tail portion 2 of the tunnel excavator 1. (2) The erector head 5 is turned by a predetermined angle. (3) Connect the next piece 3a to the previous piece 3a. (4) The operations of (2) and (3) are performed by
Is repeated for the divided pieces.

Reference numeral 6 denotes a rear gripper for taking a reaction force against the ground, 7 denotes a completed ring-shaped support member, 8 denotes a motor for moving the erector head 5, 9 denotes a cutter of the tunnel excavator 1, and 10 denotes a tunnel excavator. 1 is a main beam, 11 is a front jack, 12 is a support jack that holds the main beam 10 when the rear gripper 6 is removed, 13 is a thrust jack that advances the cutter 9 with respect to the rear gripper 6, and 14 is an excavated earth and sand. It is a belt conveyor for conveying.

[0006]

However, the conventional method of assembling the ring-shaped support member has the following problems. That is, the tunnel excavator 1 obtains a propulsive force by taking a reaction force on the ground by the rear gripper 6 behind the assembly position of the ring-shaped support member 3. In this case, the rear gripper 6 of the tunnel excavator 1 presses the assembled ring-shaped support member 7 against the ground from the inside. Therefore, when the fall prevention body attached to the frame of the piece is a collapse prevention body having a large thickness in the radial direction of the tunnel, such as an angle or the like assembled in a lattice, the rear gripper 6 and the ground are connected. There is a problem that the support function is remarkably deteriorated by being pinched and deformed.

As shown in FIG. 6, a member constituting the tail part 2 of the tunnel excavator 1 is divided into a top part 15 and a side part 16, and the intended place is a rock mass. There is no member corresponding to the lower part because it is for prevention of collapse. Then, as described above, the piece 3a of the ring-shaped support material 3
Is turned along the electoring ring 4. For this reason, when the fall prevention body is a fall prevention body such as an expanded metal or the like, the end or mesh of the expanded metal attached to the piece 3a on the front side in the turning direction is a tail of the tunnel excavator 1 at the time of turning. There is also a problem of being caught on the end face 15a of the top part 15 and the end face 16a of the side part 16 which constitute the part 2.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a tunnel excavator which can easily form a ring-shaped support member in a tail portion of a tunnel excavator without a deformation of a fall prevention body when a reaction force is taken by a rear gripper of the tunnel excavator. To provide support materials for the vehicle.

[0009]

In order to achieve the above object, a first aspect of the present invention provides a ring-shaped tunnel assembled by connecting a plurality of pieces while rotating a plurality of pieces in a tail direction of a tunnel excavator. A support material, wherein the piece comprises a pair of arc-shaped main members arranged in parallel,
A frame constituted by a connecting member for connecting the two main members, and an end is attached to an outer peripheral surface of the main member of the frame,
A plurality of axial streaks extending in the axial direction of the tunnel, and an end is attached to a connection member of the frame body, which is located outside the axial streaks, and is provided in a circumferential direction of the tunnel. And a plurality of circumferentially extending streaks extending in the vertical direction.

According to the above construction, the piece constituting the ring-shaped tunnel support material is provided with a fall prevention body for receiving rocks falling from the tunnel wall surface on the outer peripheral surface side of the arc-shaped frame body on the tunnel wall side. Attached and formed. The collapse prevention body has an axial streak extending in the axial direction of the tunnel and a plurality of circumferential streaks extending in the circumferential direction of the tunnel. It is formed thin. As a result, even if the fall prevention body is pressed against the ground by the gripper of the tunnel excavator from the inside and is sandwiched between the gripper and the ground, the deformation of the fall prevention body with respect to the frame and the fall prevention body itself No deformation occurs.

Further, the circumferential streaks constituting the above-mentioned collapse preventing body are disposed outside the axial streaks. Thus, when the pieces are connected while rotating in the circumferential direction in the tail portion of the tunnel excavator, the pieces are guided by the circumferential streaks extending in the circumferential direction so as not to be caught by the tail portions. It turns smoothly.

According to a second aspect of the present invention, there is provided the tunnel supporting material according to the first aspect of the present invention, wherein the length of the outer circumferential circumferential streaks is the inner length. It is characterized by being longer than the length.

According to the above configuration, the longer circumferential streaks are located outside the shorter axial streaks. Therefore, the circumferential streaks that are long and receive a large bending moment due to the load from the tunnel ground are supported from the inside by the axial streaks. Thus, the rigidity of the above-mentioned collapse prevention body is increased.

According to a third aspect of the present invention, in the tunnel supporting material of the first aspect of the present invention, the mounting surface of the circumferential streaks of the connecting member is the axial streaks of the main material. And one surface is formed, and the end of the circumferential streak attached to the connecting member is located radially inward of the tunnel from the center. Features.

According to the above configuration, the circumferential streaks are located outside the axial streaks, and the mounting surface of the circumferential streaks and the mounting surface of the axial streaks are different. Forming one surface. Therefore, the end of the circumferential streak attached to the connecting member is located radially inward of the tunnel from the center. As a result, there is a gap between the end of the circumferential streak and the tail of the tunnel excavator, and the circumferential streak can smoothly turn without being caught by the tail.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 is an external view of one piece constituting the tunnel support material of the present embodiment, and FIG. 2 is a sectional view taken along the line BB of FIG. This tunnel support material has a circular shape along the inner periphery of the tunnel and is constituted by a plurality of pieces 21 divided in the circumferential direction of the tunnel.

As shown in FIG. 1, the piece 21 is composed of an arc-shaped frame and a fall prevention member attached to the surface of the frame. The frame includes a pair of arc-shaped channel steels (hereinafter, referred to as main materials) 22 and 22 which are arranged to face each other.
And two main members 2 connected to both end surfaces of the main members 22 and 22.
The two main members 22, 22 are formed of a pair of connecting iron plates 23, 23 connecting the two main members 22, 22, and a connecting member 24 attached between inner side surfaces at both ends of the main members 22, 22. In addition, the iron plates for connection 23, 2
3 is provided with a bolt hole 27 into which a bolt is inserted when connected to another piece 21.

Further, the above-mentioned collapsible body includes a plurality of first round bars 25, 25,... As the axial streaks and a plurality of second round bars 26, 26, 26 as the circumferential streaks. … And formed. Then, the first round steel (axial streaks) 25 extend in the tunnel axial direction and are arranged at predetermined intervals.
The ends are attached by welding or the like to the outer peripheral surface on the tunnel wall side in 2,22. The second round bars (circumferential streaks) 26 are arranged at predetermined intervals in contact with the outside of the first round bars 25, and the ends thereof are connected by welding or the like.
Attached to. The first and second round bars 25, 2
The size of the grid formed in 6 is set to such an extent that the assumed collapsed lump does not pass.

Here, the pieces 21 are connected to each other to form a ring-shaped tunnel support material.
As shown in FIG. 3, a piece 21a having a standard shape shown in FIG. 1, a piece 21b in which one end in the arc direction of the piece 21 is inclined at a predetermined angle with respect to the radial direction of the arc, and the other end Piece 21c having three types of shapes including a piece 21c having a slope that matches the slope of piece 21b.
Prepare In the present embodiment, the three pieces 21a, one piece 21b, and one piece 21c form a tunnel support material.

The tunnel support member composed of an aggregate of the pieces 21 having the above configuration is assembled by a method of assembling a ring-shaped support member as shown in FIGS.
That is, as shown in FIG. 3, first, the piece 21b is gripped at the center by the erector head 5 with the end on the inclined surface side facing the turning direction of the erector head 5 (FIG. 3a). Next, as shown in FIG. 3B, the piece 21b is turned by the erector head 5 by a predetermined angle. Then, the first piece 21a of the standard shape is supplied to the lower part of the erector ring 4. Then, the connecting iron plates 23, 23 between the piece 21b and the piece 21a are fastened with bolts. The above operation is repeated twice to sequentially connect the second piece 21a and the third piece 21a as shown in FIGS. 3 (c) and 3 (d).
Then, the third piece 21a and the first piece 21b
A space for inserting the piece 21c is formed between them. As shown in FIG. 3 (e), the last piece 21c is fitted into this space and fastened with bolts to complete the ring-shaped tunnel support material. In this case, a slope is provided at the boundary between the first piece 21b and the last piece 21c. Therefore, the insertion of the last piece 21c can be easily performed.

The thus formed collapsible body attached to the frame of each piece 21 of the tunnel support material has a reduced thickness in the radial direction of the tunnel due to the first and second round steel bars 25 and 26 crossing each other. It is formed as follows. The first and second round steel bars 25 and 26 are attached to the outer peripheral surface of the main member 22 constituting the frame of the piece 21 closest to the inner wall of the tunnel. Therefore, even if the fall prevention body in the present embodiment is pressed from the inside by the rear gripper 6 of the tunnel excavator 1, the body is immediately sandwiched between the rear gripper 6 and the ground. As a result, the deformation of the first and second round steel bars 25 and 26 with respect to the main member 22 and the first and second round steel bars 25 and 26
The deformation of the round bars 25 and 26 themselves does not occur, and a decrease in the support function is prevented.

Further, the round steel constituting the above-mentioned collapse preventing body is
The second round steel 26 extending in the circumferential direction of the tunnel is located outside (the inner side of the tunnel) the first round steel 25 extending in the axial direction of the tunnel. Further, the tip of the second round steel 26 is attached to the connecting member 24 on the same plane as the outer peripheral surface of the main member 22. For this purpose, as shown in FIG. 2, the position of the second round bar 26 at the tip of the piece 21 in the turning direction is radially inside the position of the second round bar 26 in the intermediate portion, and the tip of the second round bar 26 There is a gap between the end portion and the tail portion 2 (the top portion 15 in FIG. 2). Therefore, when turning, each piece 21 does not catch its end in the turning direction on the end surface 15 a of the top portion 15 or the end surface 16 a of the side portion 16 constituting the tail portion 2. Therefore, according to the present embodiment, the piece 21 of the tunnel support material can be smoothly turned by being guided by the second round steel 26 extending in the circumferential direction, and can easily be a ring-shaped tunnel support. The material can be formed.

The connection between the pieces 21 of the tunnel support material is a structural weak point of the ring-shaped tunnel support material. In addition, assembling work can be shortened if the number of connecting portions is small. From the above points, it is desirable to make the circumferential length of the piece 21 as long as possible, and in the present embodiment, it is set to about 3 m to 5 m. On the other hand, the length of the piece 21 in the tunnel axis direction (piece 2
If (1 width) is too large, the interval between the two main members 22 constituting the frame becomes large, and it becomes impossible to support a large load due to the collapsed mass. Therefore, in the present embodiment, it is set to about 1 m with reference to the conventional support pitch.

In this case, the bending moment generated in the above-mentioned collapse prevention body due to the load from the ground of the tunnel is considered to be the bending moment applied to the second round steel 26 as the above-mentioned circumferential streak body in consideration of each piece 21 unit. The bending moment is larger than the bending moment applied to the first round bar 25 as the above-mentioned streaks in the axial direction. Therefore, in the present embodiment, the first round bar 25 is disposed inside the second round bar 26, and the second round bar 26 to which a large bending moment is applied is supported from the inside by the first round bar 25. . That is, according to the present embodiment, the rigidity of the collapse prevention body can be increased.

The tunnel support material formed in a ring shape as described above is pushed backward from the tail portion 2 by the jack device (not shown) or the like. When the top portion 15 and the rear end of the side portion 16 escape from the rear end and reach the support point, the above-mentioned bolts fastening the two pieces 21, 21 are adjusted to widen the interval between the two pieces 21, 21 to form a ring shape. The diameter of the tunnel support material that was assembled in this area was enlarged along the ground. Thus, one tunnel support material is installed.

As described above, in the present embodiment, the piece 21 formed by dividing the ring-shaped tunnel support material in the circumferential direction of the tunnel is formed by dividing the piece 21 in the circumferential direction of the tunnel by the axial length of the tunnel. And a frame that is curved in a large arc shape and a fall prevention body attached to the outer peripheral surface of the frame. Then, the fall prevention body is tunneled by the first round steel 25 as the axial streaks and the second round steel 26 as the circumferential streaks located outside the first round steel 25. Is formed so that the thickness in the radial direction becomes thin. Therefore, even if the fall prevention body is sandwiched between the rear gripper 6 of the tunnel excavator 1 and the ground, the fall prevention body itself does not deform, and the support function does not decrease.

Further, in the present embodiment, the above-mentioned collapsible body is formed and the first round steel (axially striped body) 25 is formed.
The second round steel (circumferentially streaked body) 26, which is longer than the first round steel 25 and is subjected to a large bending moment, is disposed outside the first round steel 25. Therefore, the second round bar 26 to which a large bending moment is applied can be supported from the inside by the first round bar 25, and the rigidity of the above-mentioned collapse prevention body can be increased.

Also, in the present embodiment, as described above, the second round bar 26 extending in the turning direction of the piece 21 is positioned outside the first round bar 25. ing. Therefore, when turning the piece 21 at the time of assembling the tunnel support material, the tip of the turning direction of the piece 21 or the first round steel 25 is attached to the tunnel excavator 1.
The end surface 15a of the top portion 15 and the side portion 1 constituting the tail portion 2
6 does not get caught on the end face 16a. Therefore,
The ring-shaped tunnel support material can be easily formed by smoothly turning the piece 21.

In the above-described embodiment, the circumferential streaks and the axial streaks constituting the fall prevention member are formed of elongated round steel bars 25 and 26. However, the present invention is not limited to this, and may be a thin strip-shaped iron plate. In short, even if it is sandwiched between the rear gripper 6 of the tunnel excavator 1 and the ground, it does not deform itself, and has a thin streak in the radial direction of the tunnel such that it can sufficiently receive falling rocks. It just needs to be your body. Further, the method of assembling the tunnel support material of the present invention is not limited to the method using the apparatus as shown in FIGS. In short, arc-shaped piece 2
Any method may be used as long as it is a method of assembling the parts 1 one after another while turning them in the circumferential direction.

[0030]

As is apparent from the above description, the piece constituting the tunnel supporting material according to the first aspect of the present invention includes a frame body composed of a pair of arc-shaped main members and a connecting member, and this frame body. And a plurality of axes extending in the axial direction of the tunnel, the ends of which are attached to the outer peripheral surface of the main material. And a plurality of circumferential streaks that are located outside the axial streaks and that extend in the circumferential direction of the tunnel with an end attached to a connecting member in the frame. With this configuration, the collapse prevention body can be formed to be thin in the radial direction of the tunnel by the streaks arranged in two directions. Therefore, even if the fall prevention body is sandwiched between the gripper of the tunnel excavator and the ground, the deformation of the fall prevention body with respect to the frame or the deformation of the fall prevention body itself does not occur, and the support function is lost. Can be prevented.

Further, the circumferential streaks constituting the above-mentioned fall prevention body are arranged outside the axial streaks.
Therefore, when connecting the above pieces while turning them in the circumferential direction of the tunnel in the tail portion of the tunnel excavator,
The piece is guided by the circumferential streaks extending in the circumferential direction so as not to be caught by the tail portion, and can be smoothly turned. That is, according to the present invention, a ring-shaped tunnel support material can be easily formed.

Further, the supporting material for a tunnel according to the second aspect of the present invention is long because the length of the circumferential streaks located on the outside is longer than the length of the axial streaks located on the inside. Therefore, the circumferential streaks that receive a large bending moment due to the load from the tunnel ground can be supported from the inside by the shorter axial streaks, thereby increasing the rigidity of the collapse prevention body.

According to a third aspect of the present invention, in the tunnel support material, the mounting surface of the circumferential streak of the connecting member is one surface with the mounting surface of the axial streak of the main material. Since the end of the circumferential streak attached to the connecting member is located radially inward of the tunnel from the center, the end of the circumferential streak is formed. There is a gap between the tunnel and the tail of the tunnel excavator. Therefore, the circumferential streak body can smoothly turn so as not to be caught on the tail portion.

[Brief description of the drawings]

FIG. 1 is an external view of a piece constituting a tunnel support material of the present invention.

FIG. 2 is a sectional view taken along the line BB in FIG.

FIG. 3 is a view showing a procedure of connecting the pieces shown in FIG. 1 to assemble them into a tunnel support material.

FIG. 4 is a longitudinal sectional view of a tunnel excavator realizing the assembling procedure shown in FIG. 3;

FIG. 5 is a sectional view taken along the line AA in FIG. 4;

FIG. 6 is a side view of a tail portion of the tunnel excavator shown in FIG.

[Explanation of symbols]

21: Peace, 22: Main material, 23
... iron plate for connection, 24 ... connection member, 25
... First round steel, 26 ... Second round steel.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Kazuo Nishikawa, Inventor Kazuo Nishikawa 2-2-2 Matsuzaki-cho, Abeno-ku, Osaka-shi, Osaka (56) References JP-A-9-21297 (JP, A) 60-62599 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21D 11/14

Claims (3)

(57) [Claims] 1. A ring-shaped tunnel support member assembled by connecting a plurality of pieces in a tail portion of a tunnel excavator while rotating the pieces in a circumferential direction, wherein the pieces are a pair of circles arranged in parallel. A frame formed of an arc-shaped main member and a connecting member for connecting the two main members; and a plurality of end members attached to an outer peripheral surface of the main member of the frame member and extending in an axial direction of the tunnel. An axial streak and a plurality of circumferential streaks that are located outside the axial streaks and that have ends attached to the connecting members of the frame and that extend in the circumferential direction of the tunnel; A support material for a tunnel, comprising a fall prevention body formed by: 2. The support material for a tunnel according to claim 1, wherein a length of the circumferential streaks located outside is longer than a length of the axial streaks located inside. Tunnel support material. 3. The supporting material for a tunnel according to claim 1, wherein a mounting surface of the circumferential streaks of the connecting member forms one surface with a mounting surface of the axial streaks of the main material. An end portion of the circumferential streak attached to the connecting member is located radially inward of the tunnel from a center portion.