JP2824618B2 - Perforation method for rebuilding existing tunnel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for perforating a wall of an existing tunnel to enable the wall of the existing tunnel to be crushed when the existing tunnel is converted into a large-diameter tunnel.

[0002]

2. Description of the Related Art In tunnels used for many years, there are places to be repaired at various places, and there is a demand for increasing the value of use by enlarging the sectional shape. In order to rebuild such an existing tunnel, it is only necessary to excavate the ground around the outer periphery of the tunnel while destroying the wall of the tunnel and expand the diameter. At present, tunnel excavation is performed using an excavator having a rotary cutter head having a larger diameter than an existing tunnel.

[0003]

However, for an existing tunnel in which a reinforcing bar is buried in the wall, a concrete portion of the wall can be cut with a crushing cutter mounted on a conventional tunnel excavator. However, it is not possible to cut the reinforcing bars continuously buried in the wall of the existing tunnel, so that it is difficult to expand and reconstruct the existing tunnel by the tunnel excavator alone. Also, even if the rebar can be cut by a crushing cutter,
There is a problem in that the cutting edge of the crushing cutter is severely worn and it is impossible to excavate a tunnel over a long distance.

[0004] The present invention has been made in view of such problems, and its object is to bury the existing tunnel vertically and horizontally in the wall of the existing tunnel prior to the expansion and renovation of the existing tunnel. It is an object of the present invention to provide a method of perforating a wall for cutting a reinforcing bar into small dimensions and facilitating crushing of the wall.

[0005]

In order to achieve the above-mentioned object, a method for perforating a wall for rebuilding an existing tunnel according to the present invention is provided by lining a concrete wall in which reinforcing bars are buried in a circumferential direction and a longitudinal direction. A wall piercing device is movably disposed in an existing tunnel, and the concrete wall is pierced at appropriate intervals by the wall piercing device without dividing the concrete wall in the circumferential direction and the length direction. It is characterized in that the buried reinforcing bars are cut into lengths that can be removed by a tunnel excavator.

[0006]

[Function] When the wall of an existing tunnel is pierced from the inner peripheral surface by the wall piercing device, the concrete wall on the inner layer side of the wall is pierced, and the reinforcing steel buried inside according to the hole diameter. It is cut into fixed length dimensions. After cutting the reinforcing bar, the wall drilling device is retracted and separated from the wall, and then the wall drilling device is moved in the circumferential direction or the length direction of the tunnel, and then the wall is drilled again in the same manner as described above. To cut the buried rebar.

[0007] The rebar cutting work by this drilling is performed in the length direction and the circumferential direction of the tunnel to divide the buried rebar into small dimensions. The length dimension is a length that can be removed by a tunnel excavator. Is to be divided. Examples of such a drilling method include, for example, sequentially drilling in a helical direction with an interval equal to or less than a drilling diameter by a wall drilling device and a drilling interval in a tunnel length direction not more than a rebar length that can be removed by a tunnel excavator. This can be done by piercing.

Therefore, if the tunnel excavator is advanced following the drilling operation of the existing tunnel wall by the wall drilling device, the ground around the outer periphery of the existing tunnel is excavated by the cutter head and provided on the cutter head. The crushing cutter crushes the wall of the existing tunnel from its rear end. At this time, since the reinforcing bars in the wall are separated into small dimensions by the wall drilling device as described above,
The brittle concrete portion is cut off by the cutting cutter, and the rebar pieces cut into small dimensions are removed integrally with the concrete pieces. In this way, if the reinforcing bars in the existing tunnel wall are cut in advance by the wall drilling device, the tunnel whose existing tunnel has been expanded by the tunnel excavator can be efficiently reconstructed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example of an apparatus for carrying out a method for perforating a wall of an existing tunnel T, and A denotes the wall perforating apparatus. The support frame 3 is supported by the front and rear movement guides 1 and 2, and the wall piercing tool 4 is provided on the support frame 3. The front and rear movement guides 1 and 2 are provided with a caterpillar-shaped moving body portion 1a, 2a and a leg 1 on the moving body portion 1a, 2a.
b, 2b, a support body 1c, 2c standing and fixed, and a support cylinder 1d fixedly inserted in the center of the support parts 1c, 2c in an inserted state and opened in the axial direction of the existing tunnel T. , 2d, and jacks 1e, 2e mounted and erected on the upper periphery of the support cylinders 1d, 2d,
Grippers 1f and 2f are fixed to the rod ends of these jacks 1e and 2e, and are press-fitted to the inner peripheral surface of the wall body t of the existing tunnel T so as to be detachable.

The support cylinders 1d of the front and rear movement guides 1 and 2
A center beam 5 is rotatably inserted and supported between 2d. The support cylinder 1d of the front moving guide 1 can slide back and forth with respect to the center beam 5, but the support of the rear moving guide 2 is supported. The cylindrical body 2d is configured to be able to move back and forth integrally with the center beam 5. Further, the support frame 3
As shown in FIG. 2, the center tube shaft portions 3c and 3d are provided on the front and rear of the left and right frame portions 3a and 3b so as to be coaxial with each other.
The front tube shaft portion 3c is integrally connected to the rear end of the center beam 5, and the front and rear movement guide 1 is connected through the center beam 5,
The rear pipe shaft portion 3d is formed to be long and can be connected to a tunnel excavator B described later.

The wall drill 4 is disposed between the left and right frame portions 3a and 3b of the support frame 3, and as shown in FIG.
, A drive motor 43 housed in the hydraulic cylinder 42 and integrally connected to the piston 41, and a motor rotating shaft inserted through the center of the piston 41 and projected to the outside. It is composed of a core cutter 45 fixed to the tip of 44. The core cutter 45 has a plurality of cutting bits 46 protruding from an opening edge of a bottomed cylindrical body.

The center of both sides of the cylinder 42 of the wall piercing tool 4 is rotatably pivotally attached to and supported by the short shaft 47 at the opposing portions of the left and right frame portions 3a and 3b of the support frame 3, and the left and right frame portions 3a are supported. , 3b, the bottom of the cylinder protruding downward and the rear end of the center beam 5 are connected by a jack 6, and the jack 6 is operated to rotate around a short axis 47 so that the cylinder can be stored in the left and right frame portions 3a, 3b. Also, it is configured to stand up from that state.

Furthermore, a gear 7 is provided at the rear end of the center beam 5.
On the other hand, a rotation motor 8 is installed on the support cylinder 2d of the rearward movement guide 2, and a small gear 9 fixed to this rotating shaft is provided.
Are meshed with the gear 7 to rotate the support frame 3 integrally with the center beam 5 by driving the motor 8 to rotate the wall piercing tool 4 in the circumferential direction.

The wall drilling apparatus A configured as described above is
It moves inside the existing tunnel T prior to the tunnel excavator B, and pierces the wall t at an appropriate depth in the circumferential direction and the length direction of the wall t from the inner circumferential surface at an appropriate depth to form the inside of the wall t. After the rebar provided in the tunnel T is divided, the tunnel excavator B crushes the wall t of the existing tunnel T to construct a large-diameter tunnel.

The tunnel excavator B is, as shown in FIG.
The body is divided into three parts at the front and rear, and is formed into a front body 10, an intermediate body 11 and a rear body 12 having a diameter larger than the outer diameter of the wall t of the existing tunnel T, and a cutter head is provided at an opening front end of the front body 10. 13 is arranged rotatably. This cutter head 13 is shown in FIG.
As shown in the figure, a cutting cutter 14 for excavating the ground on the outer periphery of the existing tunnel T is radially provided on the outer peripheral portion thereof, and a slip inlet 15 is provided between the cutting cutters 14 adjacent to each other in the circumferential direction. Further, a crushing cutter 16 in the shape of a solobang ball having a sharp tip for cutting off the wall t of the existing tunnel T from the end face side is provided at an appropriate interval in the circumferential direction.

Further, the cutter head 13 has a cylindrical portion 17 integrally provided rearward from the outer peripheral edge thereof,
At a plurality of locations on the inner peripheral surface of the cylindrical portion 17, slip-raising plates 18 are provided. Further, the rear end of the cylindrical portion 17 is rotatably supported on the outer peripheral portion of the front surface of a partition 19 extending from the intermediate portion of the front body 10, and is also fixed to an internal gear 20 fixed to the inner peripheral surface of the rear end. 19
A gear 22 fixed to a rotating shaft of a drive motor 21 mounted on the back surface of the drive gear 21 is engaged with the drive motor 21 to rotate the cutter head 13.

Reference numeral 23 denotes a fixed cylindrical shaft which penetrates the center of the cutter head 13 and has its rear end fixed to and supported by the center of the partition wall 19, and whose front part projects into the center of the rear end of the existing tunnel T. Rear tube shaft part of the support frame 3 of the wall drilling device A
3d is slidably and rotatably inserted into it, and
The rear end of the tube shaft portion 3d is configured to be locked from the front end of the fixed shaft cylinder 23 so that it cannot be removed. Further, the fixed cylindrical shaft 23 is provided with a shear receiving port 24 which is opened upward behind the cutter head 13, and the unloading belt conveyor 25 which is inserted into the fixed cylindrical shaft 23 and disposed in the slip receiving port 24. The discharge belt conveyor 25 extends to the rear discharge end with the front end facing.

The intermediate body 11 of the tunnel excavator B has a front body 10
A plurality of propulsion jacks 26 are disposed at appropriate intervals in the circumferential direction, and the front and rear ends of these propulsion jacks 26 are connected to the front body 10 and the rear body. The front and rear bodies 10, 12 can be freely moved toward and away from each other by operating the propulsion jack 26. Reference numeral 27 denotes a plurality of grippers disposed on the rear fuselage 12. The jacks 28 disposed inside the rear fuselage 12 project outward and outward from the outer peripheral surface of the rear fuselage 12, and are enlarged by the cutter head 13. The rear fuselage 12 is fixed to the excavation wall surface of the tunnel C so that it can be freely attached to and detached from the excavation wall.

With the tunnel excavator B constructed as described above, the existing tunnel T having a horseshoe-shaped cross section as shown in FIG.
In order to excavate and renovate in the diameter-expanding direction, first, the reinforcing bar D embedded in the wall t of the existing tunnel T by the above-described wall drilling device A provided in the existing tunnel T is longitudinally and circumferentially. Cut at predetermined dimensions in the direction.

At the time of this cutting, the grippers 1f and 2f of the front and rear moving guides 1 and 2 are pressed against the inner surface of the wall t, and the wall mounted on the support frame 3 via the center beam 5 by the front and rear moving guides 1 and 2. The perforator 4 is fixed at a predetermined position. Thereafter, the hydraulic cylinder 42 of the wall drill 4 is operated to move the core cutter 45 to the wall surface side, and the drive motor 43 is operated to rotate the core cutter 45. When the core cutter 45 is pressed against the inner surface of the wall t,
As shown in FIG. 7, the concrete wall portion is cut into an annular slot shape by the cutting bit 46, and when the core cutter 45 is further advanced in the thickness direction of the wall t, the concrete wall is embedded in the wall t. As shown in FIG. 8, the reinforcing bar D is cut to a length corresponding to the diameter of the core cutter 45.

In this case, when the intersection of the reinforcing bar D buried in the length direction of the wall t and the reinforcing bar D1 buried in the circumferential direction is cut, both the reinforcing bars D, D1 can be cut at the same time. If the depth from the inner surface of the wall t to the portion where the reinforcing bar D is embedded is deeper than the length of the core cutter 45,
First, the concrete portion up to the depth to be cut by the core cutter 45 is cut and removed, and then the rebar D is cut by inserting the core cutter 45 again into the removed mark. Since the concrete wall is fragile, when the concrete wall is cut by the core cutter 45, the concrete wall is received in the core cutter 45 while being divided into concrete pieces, and the cut rebar pieces are also accommodated in the core cutter 45.

The concrete piece and the reinforcing steel piece accommodated in the core cutter 45 are separated from the wall t by the motor 8 and then driven by the motor 8 via the meshing gears 7 and 9.
By rotating the support frame 3 to turn it downward, it is discharged from the inside of the core cutter 45 onto the bottom surface of the existing tunnel T.

When the desired portion of the wall t is cut by the core cutter 45 in this manner, as shown in FIG.
A circular hole E is formed from the inner peripheral surface to the vicinity of the outer peripheral surface. After the circular hole E is drilled, the support frame 3 is rotated by the drive of the motor 8 so that the wall drill 4 is formed.
Was displaced by a predetermined angle in the circumferential direction of the existing tunnel T, and the wall portion was pierced by the core cutter 45 of the wall piercing tool 4 in the same manner as described above to cut and remove a fixed length portion of the embedded reinforcing bars D and D1. A circular hole E is provided. Similarly, circular holes E are formed in the wall B at predetermined intervals in the circumferential direction.

The circular hole E in the length direction of the wall t of the existing tunnel T is formed by moving the wall drilling device A forward. That is, after the grippers 1f and 2f are separated from the wall surface, the front and rear movement guides 1 and 2 are actuated to advance the support frame 3 integrated with the center beam 5 by a fixed distance in the length direction, and again at that position. 1
The wall body t is pierced by pressing the wall body piercing tool 4 attached to the support frame 3 at a predetermined position by pressing the f and 2f against the wall surface.

Although the front and rear movement guides 1 and 2 can be independently driven, the front and rear movement guides 1 and 2 are connected by a telescopic jack (not shown) without providing driving means. 1 gripper part 1f
The wall piercing tool 4 is moved forward by separating the gripper portion 1f of the rearward moving guide 2 from the inner wall surface of the rear moving guide 2 while pressing the rearward moving guide 2 forward by pressing the rear moving guide 2 forward. It is also possible to configure so that

In this manner, at the position advanced by a predetermined distance, the wall drill 4 is operated in the same manner as described above to form a circular hole E in the wall t, and the embeded reinforcing bars D and D1 of the portion are fixed in length. , Cutting and removing. The perforation pitch of the circular holes E is, as shown in FIG. 7, the distance between the peripheral edges of the circular holes E and E in the circumferential direction of the wall t.
L1 is set so as to be equal to or less than the diameter of the circular hole E, and in the longitudinal direction, on the extension in the longitudinal direction of the intermediate portion of the circular holes E, E adjacent in the circumferential direction, the interval equal to or less than the diameter of the core cutter. The holes are drilled sequentially at a constant pitch with the presence of L2. In this case, the concrete walls are continuously formed by piercing so that the opposing peripheral edges of the circular holes E, E which are obliquely adjacent to each other do not overlap, that is, have a small space also in the spiral direction. Reinforcing bars D, D1 buried in the longitudinal and circumferential directions
Is divided into small dimensions. By piercing at such a pitch, the vertical and horizontal rebars D and D1 can be divided regardless of whether or not the intersection of the rebars D and D1 is cut.

Since the rebars D and D1 need only be divided into lengths that can be taken in and removed by the tunnel excavator B as described later, other than the above-described methods of drilling, for example, as shown in FIG. Assuming a rectangular plane F whose wall surface length and width are equal to the reinforcing bar length that can be taken in and removed by the tunnel excavator B, the circular holes E, E adjacent diagonally in this rectangular plane F do not overlap. And a rectangular plane F
When all the circular holes E are projected on one side, the holes may be formed so as to be continuous. In this case, the circular holes E may be formed in a zigzag pattern as shown in FIG.

Further, when the wall piercing device A capable of piercing the large-diameter circular hole E is used, the large-diameter circular hole E is formed at the center of the four sides of the rectangular plane F as shown in FIG. By arranging, the reinforcing bars D and D1 embedded in the circumferential direction and the length direction can be cut for each of the above dimensions. In short, the lining portion is pierced by the wall piercing device in a spiral direction with an interval of less than the piercing diameter, and the piercing interval in the tunnel length direction is less than the rebar length that can be removed by the tunnel excavator. I just need.

After a plurality of circular holes E are drilled in the appropriate length of the wall t of the existing tunnel T in this way, the tunnel excavator B is propelled to rotate the cutter head 13 so that the existing tunnel T is rotated. The wall t is crushed and excavation of the enlarged diameter tunnel C is performed. In this excavation, first,
The rear body 12 is fixed by pressing the gripper 27 on the side of the rear body 12 from the rear body 12 and pressing it against the excavated wall surface of the already enlarged excavation tunnel C. Thereafter, the rear body 12 receives a reaction force. The front body 10 is propelled by stopping and extending the propulsion jack 26, while the drive motor 21 is operated to rotate the cutter head 13.

The propulsion of the front body 10 and the rotation of the cutter head 13 excavate the ground on the outer periphery of the existing tunnel T with the cutting cutter 14 arranged on the outer periphery of the cutter head 13 and crush the ground on the inner periphery. Cutter 16 is in existing tunnel T
While digging into the rear end face of the wall t, the wall t is crushed. That is, the sharp edge of the outer periphery of the crushing cutter 16 cuts into the concrete end face of the wall t to generate a crack in the concrete, and the concrete is crushed as the cutter head 13 rotates. At this time, since the reinforcing bars D and D1 in the wall t are cut into small pieces by the core cutter 45 of the wall drill 4, if the concrete portion is cut off as a concrete piece by the crushing cutter 16, the reinforcing bar D The piece is separated from the concrete wall and taken into the tunnel excavator B together with the excavated earth and sand from the inlet 15 of the cutter head 13 integrally with the concrete piece.

Debris such as concrete pieces, reinforcing bar pieces, excavated earth and sand taken into the tunnel excavator B are scraped up by a scraping plate 18 fixed to the back of the cutter head 13 and then fall to fall into a receiving port 24. Belt conveyor 25
It accumulates on top and is discharged backward. Prior to the excavation of the expanding tunnel C by the tunnel excavator B and the crushing of the wall t of the existing tunnel T, the rebar cutting work by the core cutter 45 of the wall drilling device A is performed as described above, and this is repeated. The existing tunnel T is cut and renovated over its entire length, and the enlarged diameter tunnel C is built.

In the embodiment described above, the center beam 5 is rotatably supported by the front and rear movement guides 1 and 2, and the support frame 3 of the wall drill 4 having the core cutter 45 is mounted on the center beam 5. The connecting frame is connected and the rear portion of the support frame 3 is supported by a fixed cylindrical shaft 23 protruding from the center of the tunnel excavator B. However, the present invention is not limited to such a structure. The front and rear ends of the support frame 3 of the piercing tool 4 are
And may be configured to move independently in the existing tunnel T without being connected to and supported by the tunnel excavator B. In short, the core cutter The present invention can be satisfied by making the wall piercing tool 4 provided with 45 movable in the length direction and the circumferential direction of the existing tunnel T.

[0033]

As described above, according to the method for perforating a wall for rebuilding an existing tunnel according to the present invention, a wall is formed in an existing tunnel covered with a concrete wall in which a reinforcing bar is buried in a circumferential direction and a longitudinal direction. A body piercing device is movably disposed, and the concrete wall is pierced at appropriate intervals by the wall piercing device without dividing the concrete wall portion in a circumferential direction and a longitudinal direction, and a buried reinforcing bar is tunnel-excavated. It is characterized by being cut for each length dimension that can be removed by, regardless of the cross-sectional shape and diameter of the existing tunnel, regardless of the size of the existing tunnel, buried vertically and horizontally in the wall of the existing tunnel by the wall drilling device It is possible to reliably divide the existing reinforcing bar from the inner peripheral surface side of the wall at desired length dimensions, and to maintain the shape of the existing tunnel by continuing the concrete part of the wall even if the reinforcing bar is split. State It can be placed.

Accordingly, if the tunnel excavator is propelled following the wall drilling device, the reinforced concrete wall of the existing tunnel is crushed by the cutter head of the tunnel excavator, and the broken reinforcing bars in the wall are removed. It is possible to efficiently build a tunnel with an enlarged diameter of an existing tunnel.

[Brief description of the drawings]

FIG. 1 is a side view of a wall punch according to the present invention;

FIG. 2 is a simplified plan view of the support frame portion,

FIG. 3 is a vertical front view of an existing tunnel,

FIG. 4 is a longitudinal side view showing a perforated state;

FIG. 5 is a simplified longitudinal side view of a tunnel excavator following a wall drilling device;

FIG. 6 is a front view of the cutter head,

FIG. 7 is an exploded view of a wall showing a reinforcing bar cut state,

FIG. 8 is a longitudinal sectional view thereof,

FIG. 9 is a plan view showing an example of a perforated state;

FIG. 10 is a plan view showing another example of a perforated state;

FIG. 11 is a plan view showing still another example of a perforated state.

[Explanation of symbols]

 1, 2 Back and forth movement guide 3 Support frame 4 Wall drilling tool 45 Core cutter A Wall drilling machine T Existing tunnel t Wall D, D1 Reinforcing bar E Round hole

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-163892 (JP, A) JP-A-5-163897 (JP, A) JP-A-5-321584 (JP, A) JP-A-5-163584 290894 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) E21D 9/06 301

Claims (2)

(57) [Claims] 1. A wall piercing device is movably disposed in an existing tunnel covered with a concrete wall in which a reinforcing bar is buried in a circumferential direction and a length direction, and the concrete is pierced by the wall piercing device. Renovation of existing tunnels, characterized in that the wall body is perforated at appropriate intervals without dividing the concrete wall part in the circumferential direction and the length direction, and the embedded reinforcing bars are cut into length dimensions that can be removed by a tunnel excavator. Perforation method for wall. 2. The lining portion is sequentially pierced in a spiral direction with an interval equal to or less than the piercing diameter by a wall piercing device, and the piercing interval in the tunnel length direction is set to be equal to or less than the rebar length that can be removed by a tunnel excavator. 2. The method of perforating a wall for rebuilding an existing tunnel according to claim 1, wherein the perforation is carried out.