JP3210621B2 - Support method for tunnel excavation wall - 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 supporting a rock excavation wall surface excavated by a tunnel excavator.

[0002]

2. Description of the Related Art When a tunnel is excavated by a tunnel excavator, the excavated tunnel wall surface may fall off or fall down. A ring-shaped support made of H-section steel is assembled along with a lining member such as expanded metal or a wire mesh between the adjacent ring-shaped supports, and is loosened from the tunnel wall surface in the tunnel by the lining member. It forms a shoring that prevents the rock mass from collapsing.

[0003]

However, according to the above-mentioned prior art, since the assembling of the shoring is performed behind a tunnel excavator in which the excavated tunnel wall surface is exposed, a ring-shaped shoring member is required. There is a risk that the bedrock may collapse when assembling or stretching the lining member, which is extremely dangerous and that the work cannot be performed smoothly. For this reason, a ring-shaped liner is formed by connecting a rectangular frame formed by stretching a wire mesh body on a rectangular steel frame curved in an arc shape in the tunnel circumferential direction in the skin plate of the tunnel excavator. After assembling, a method of forming a support by sending it to the tunnel excavation wall side has also been proposed, but since the liner assembled in the skin plate is smaller in diameter than the tunnel excavation wall, it was sent out to the tunnel wall side Sometimes a gap is created between the liner and the tunnel excavation wall.

Further, the above-mentioned liner supports the tunnel excavation wall surface over its entire length while being sequentially connected every time a tunnel excavator excavates a certain length of the tunnel, so that the excavation wall surface is free from cracks and collapse. In addition to this, there is a problem that not only is the material cost wasted and uneconomical, but also the construction work of the shoring requires more labor than necessary.

The present invention has been made in view of such a problem, and an object of the present invention is to observe a tunnel excavation wall surface from the inside of a skin plate and to detect a crack or a collapsed tunnel excavation wall surface from the skin plate. When exposed to the rear, a tunnel that supports the digging wall while sending out the liner that has been assembled to the skin plate in advance from the skin plate and reliably preventing the rock from falling or falling off from the loose part of the digging wall It is an object of the present invention to provide a method for supporting an excavated wall.

[0006]

In order to achieve the above object, a method of supporting a tunnel excavation wall surface according to the present invention comprises a plurality of rectangular frame-shaped support pieces curved in a tunnel circumferential direction in a skin plate of a tunnel excavator. Assemble a liner consisting of the following: ゝ While being built into the skin plate, determine the nature of the ground on the tunnel excavation wall surface, and if the characteristics are poor, the tunnel excavation wall portion will follow the tunnel excavator and follow the skin plate When exposed, the liner contained in the skin plate is sent out relatively backward from the skin plate and adheres to the tunnel excavation wall portion to support the excavation wall portion, and the properties of the tunnel excavation wall surface are good. Characterized by digging with the liner built into the skin plate without sending it to the tunnel excavation wall Than it is.

In the above-mentioned method for supporting a tunnel excavation wall surface, the means for bringing the liner into close contact with the tunnel excavation wall surface is provided when the rear portion of the liner is relatively fed from the rear end of the skin plate. A method of increasing the diameter of the rear part and increasing the diameter of the front part which is subsequently sent out to make close contact with the tunnel excavation wall surface, or as described in claim 3, the rear part of the liner is relative to the rear end of the skin plate. When it is sent out to the tunnel, the rear part is pushed up, and the front part sent out subsequently is pushed up to make close contact with the tunnel excavation wall surface.

According to a fourth aspect of the present invention, in the method for supporting a tunnel excavation wall surface, a rock fall prevention member is provided on at least an outer peripheral surface of an upper half portion of the liner.

[0009]

The liner can be formed by connecting a plurality of rectangular frame-shaped support pieces curved in an arc shape in the direction along the tunnel excavation wall in the circumferential direction of the tunnel. Performed in the rear end of the plate. On the other hand, the tunnel excavation wall excavated by the tunnel excavator is observed from the inside of the skin plate through a slit or the like provided on the skin plate, and there is a rock mass portion of poor quality in which a crack or a collapse has occurred on the tunnel excavation wall surface. In such a case, when the rock portion is exposed rearward from the skin plate according to the excavation of the tunnel excavator, the liner previously assembled in the skin plate is sent backward from the skin plate and the rock portion is transferred to the liner. Supported by. Also, in the case of a rocky excavation wall of good quality with no cracks in the rock on the wall of the tunnel excavation, even if that part is exposed behind the skin plate, it will remain in place without being supported by the liner. Keep it.

As means for bringing the liner into close contact with the tunnel excavation wall without causing a gap between the tunnel excavation wall and the liner, adjacent support pieces on the lower peripheral side of the liner are integrally connected in advance. When the rear half of the liner is sent out from the skin plate to the tunnel excavation wall side according to the excavation of the tunnel excavator, the rear end side of the separably joined portion is extended with a jack or the like. The diameter of the liner is tapered from its front end to its rear end by pushing and expanding in the circumferential direction by using, and the rear end of the expanded liner is brought into full contact with the tunnel excavation wall surface. Furthermore, when the entire liner is sent out to the tunnel excavation wall side according to the excavation of the tunnel excavator, the front end side of the detachably joined portion of the liner is circumferentially expanded in the same manner as described above. The diameter of the liner may be increased so as to have the same diameter as the rear end side, and the entire outer periphery of the liner may be brought into close contact with the tunnel excavation wall surface.

As another means for bringing the liner into close contact with the tunnel excavation wall, when the rear half of the liner is sent out from the skin plate to the tunnel excavation wall side in accordance with the excavation of the tunnel excavator, its rear end is upwardly jacked. When the entire liner is sent out to the tunnel excavation wall side according to the excavation of the tunnel excavator, the front end side of the liner is pushed up by a jack. Thus, the upper half of the liner may be brought into close contact with the upper half wall of the tunnel excavation wall.

Further, even if a crack or the like is generated in the lower half of the tunnel excavation wall surface, there is no danger that the bedrock will collapse in the tunnel. By installing a rock fall prevention member such as a wire mesh only on the upper peripheral side of the tunnel excavation wall surface, material costs can be reduced and workability can be improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a specific embodiment of the present invention will be described with reference to the drawings. FIGS. 1 and 2 show cracks and collapses in rocks on a tunnel excavation wall T excavated by a tunnel excavator 10. FIG. The excavated wall portion T 'having poor properties is supported by the liner 1 which is a ring-shaped support, and the tunnel excavated wall surface T having good properties without cracks or collapse is exposed without being supported by the liner 1. 3 shows a state in which the liner 1 is intermittently constructed in the length direction of the tunnel with the liner 1 in the closed state.

The tunnel excavator 10 has a cylindrical skin plate 11 having a plurality of slits 30 for observing rock properties at a plurality of locations in the upper half thereof.
A support member 12 integrally provided with the support member 11; a cutter plate 13 rotatably supported by the support member 12 and rotationally driven by a drive motor (not shown) mounted in the support member 12; A beam member 14 having a front end integrally fixed to the rear end of the support member 12 and extending horizontally rearward from the rear end of the skin plate 11 through a central space of the skin plate 11; A telescopic front gripper 15 integrally mounted on the upper, lower, left and right sides of the member 12, and a beam body 14
A rear support 16 protruding downward from the lower surface of the rear end and extending vertically by a jack 16a; a rear gripper 17 slidably disposed along the lower surface of the beam body 14;
It is composed of a propulsion jack 18 connecting the rear gripper 17 and 12.

The skin plate 11 includes a beam member 14.
The rear gripper 17 is integrally fixed and supported on the outer peripheral surface of the
As is well known, both sides of the tunnel excavation wall T are provided on the rear side of the beam body 14 projecting rearward from the lower side of the beam receiver 19 slidable relative to the beam body 14. , And both rear grippers 17, 17 and both sides of the rear surface of the support member 12 are connected by the propulsion jacks 18, 18, respectively. The earth and sand excavated by the cutter plate 13 is discharged backward by an appropriate carrying-out means such as a conveyor (not shown).

In the tunnel excavator 10 configured as described above, the tunnel excavator 10 shown in FIG. The support pieces 1A, 1B, and 1C are assembled in a ring shape to form a liner 1 and a swivel-type liner assembling eletax 21 that holds the liner 1 and is built into the skin plate 11 is provided. A plurality of liner pushing jacks 22 are mounted on the inner peripheral surface of the skin plate 11 at appropriate intervals in the circumferential direction.

On the other hand, in the tunnel excavator 10 shown in FIG. 2, a sliding frame 23 which can reciprocate back and forth between the skin plate 11 and the tunnel excavation wall T is slidably fitted on the beam body 14. The liner 1 assembled in the skin plate 11 is supported on the sliding frame 23, and front and rear push-up jacks 24 and 25 are provided to push up the liner 1 when the liner 1 is sent out to the tunnel excavation wall T side. It is attached to the state. Further, the sliding frame 23 and the beam receiver 19 are connected by a sliding jack 26.

In the rear end portion of the skin plate 11 of the tunnel excavator 10 having the above-described configuration, first, a plurality of support pieces 1A, 1B, having a constant arc length curved in an arc shape.
1C is connected in the circumferential direction to form a front circular ring-shaped support body having a diameter smaller than the diameter of the tunnel excavation wall surface T and having a rock-fall prevention member 27 stretched on the outer peripheral surface of the upper half part, that is, the liner 1. . The support pieces 1A to 1C are, as shown in FIGS. 3 to 5, front and rear main girders 1a curved in an arc along the tunnel excavation wall surface T,
It consists of a steel rectangular frame that is integrally fixed between both ends in the length direction of 1b by flat joint plates 1c, 1c. And, as shown in FIG. 3, the support piece 1A disposed along the upper peripheral wall of the tunnel excavation wall T is a rock collapse made of a wire mesh in which bar-shaped metal wires are combined in a grid at the outer peripheral open end of the rectangular frame. It has a structure in which a prevention member 27 is stretched.

On the other hand, as shown in FIG. 5, the support piece 1C disposed along the lower peripheral wall, which is the bottom of the tunnel excavation wall T, is formed of a steel rectangular frame having no rock fall prevention member. . The support pieces 1B provided between the upper and lower support pieces 1 and 1B and disposed along both side walls of the tunnel excavation wall surface T, as shown in FIG. Rock fall prevention member 27 made of wire mesh
Is stretched. In addition, each support piece 1A
Several bolt insertion holes 28 and 29 for connecting supporting pieces adjacent to each other in the tunnel length direction and the circumferential direction are drilled in the main girders 1a and 1b and the joint plate 1c of ~ 1C.

Although the liner 1 is formed from four support pieces in FIG. 3, the liner may be constructed by combining four or more support pieces. In this case, the rock fall prevention member 27 is used. An intermediate support piece 1B between the uppermost support piece 1A having the rocking support member 1A and the lowermost support piece 1C having no rockfall prevention member is a support piece having the rockfall prevention member 2 stretched. In some cases, the support piece may be combined with a support piece that is not stretched up and down.

The support pieces 1A, 1B and 1C are connected to a tunnel excavator 10 having a swivel-type liner assembling erect 21 shown in FIG.
The case where the liner 1 is assembled in the skin plate 11 will be described. As shown in FIG. 6, the swiveling liner assembling eleector 21 rotates around the beam member 14 and forms a rack 32 on the inner peripheral surface. Erecting ring 31
A drive motor 33 installed on the beam body 14 and having a pinion 34 fixed to the rotation shaft thereof meshed with the rack 32
And an erector head 35 attached to the erector ring 31 and capable of engaging and disengaging from the support piece, and a plurality of support piece support brackets 36 erected on the outer peripheral surface of the erector ring 31.

First, the erector head 35 of the erector 21
After supporting the support piece 1C, the drive motor 33 rotates the electoring ring 31 in the circumferential direction of the skin plate 11 to move the support piece 1C upward along the inner peripheral surface of the skin plate 11 by a predetermined circumferential length. After that, the support piece 1B is held at that position, and then the support piece 1B is joined to the support piece 1C by connecting the joint plates 1c, 1c facing each other to each other by bolts and nuts, and the support piece 1B is connected to the support fitting 36. , So that the support pieces 1B and 1C are integrally pivoted upward by turning the erector ring 31 in the same direction again. .

Similarly, the support piece 1B is attached to the support piece 1B.
A, the support pieces 1A in which the rock-fall prevention members 27 are stretched by sequentially joining and connecting the support pieces 1B and turning in the same direction while being supported by the support fittings 36.
Assembles the liner 1 with the uppermost part and the unsupported support piece 1C at the lowermost part. The adjacent support pieces on the lower peripheral side of the liner 1 are separated without being connected. In the case where the support piece 1C is formed in a two-part shape, and the liner 1 in a state where there is an interval between these support pieces on the lower peripheral side of the skin plate 11 to support the tunnel excavation wall surface T Alternatively, a key piece may be interposed between these support pieces to form a liner 1 having an increased diameter.

The liner 1 assembled in this way is held by the erector 21 and built in the skin plate 11.
On the other hand, the tunnel excavation wall T excavated by the tunnel excavator 10 can be visually inspected from inside the skin plate 11 through the slit 30 or by inserting an inspection rod to determine whether the rock has cracks or collapse. Inspect the properties of the wall. Then, when a badly-excavated wall portion T ′ in which a crack or a collapse has occurred is detected, the excavated wall portion T ′ relatively moves rearward according to the excavation of the tunnel excavator 10 and moves from the rear end of the skin plate 11. When the liner 1 is released from the rear by exposing the liner 1 to the skin plate 11 according to the excavation of the tunnel excavator 10, the liner 1 is released by holding the liner 1.
Extrude from

The liner 1 detached from the erector 21 has its lower peripheral portion received by the bottom surface of the tunnel excavation wall surface T exposed from the cutout portion 20 of the skin plate 11. Accordingly, in this state, the liner pushing jack 22 The liner 1 moves relatively rearward according to the excavation of the tunnel excavator 10 without further extension. It is not always necessary to provide the cutout portion 20. When there is no cutout portion, the cutout portion 20 may be sent out using the pushing jack 22. When the rear half of the liner 1 is sent out from the skin plate 11 to the tunnel excavation wall T side, as shown in FIG.
Joint plates 1c, 1c of adjacent support pieces on the lower peripheral side of
The rear half of the liner 1 is expanded by inserting a jack 37 between the rear ends of the liner, and the outer peripheral surface of the liner 1 is brought into contact with the excavated wall portion T 'where cracks are formed, causing the rock to collapse. To prevent it.

After the diameter of the rear end of the liner 1 is enlarged, the tunnel excavator 10 further excavates and the front half of the liner 1 is relatively sent out from the skin plate 11 into the tunnel excavation wall T to the front end. A jack is provided between the front ends of the joint plates 1c, 1c of the adjacent support pieces on the lower peripheral side of the liner 1.
The excavated wall part T 'with poor quality of rocky material where cracks etc. are generated by expanding the liner so as to have the same diameter by extending with the interposition of 37 A key piece (not shown) or the like is interposed between the portions 1c, 1c, or fixed at a fixed interval with bolts so as to be in full contact with the inner peripheral surface of the excavated wall portion T '. Let it be liner 1.

During the delivery of the liner 1 to the tunnel excavation wall T side, the next small-diameter liner 1 is assembled using the above-mentioned erector 21 and the poorly excavated wall portion is formed.
When the length of T ′ is large, the rear end face of the liner 1 is continuously joined to the front end face of the expanded liner 1 in accordance with the excavation of the tunnel excavator 10 and relatively to the tunnel excavation wall T side. Then, the rear end and the front end are sequentially expanded by the jack 37 in the same manner as described above, so that the excavated wall portion T 'is entirely supported.

On the other hand, the slit 30
If the rock on the tunnel excavation wall T observed through is a good rocky excavation wall without cracks,
Even if that portion is exposed behind the skin plate 11, the liner 1 is
Built in 11 Therefore, the tunnel excavation wall T is shown in FIG.
As shown in the figure, the excavated wall part T '
Only the support structure is supported by the liner 1.

Next, as shown in FIG. 2, a tunnel excavator 10 having front and rear pushing jacks 24 and 25 on a sliding frame 23 is provided.
In the case of (1), first, the liner 1 assembled by an erector (not shown) is pushed up and down with the sliding frame 23 positioned in the rear end of the skin plate 11, and jacks 24, 25.
To support as shown in FIG. As described above, the liner 1 has the support pieces 1A on which the rock fall prevention members 27 are stretched, with the support pieces 1A on the upper peripheral side and on both sides thereof.
B and 1B have a structure in which a support piece 1C, which is not provided with a rock fall prevention member 27 on the lower peripheral side, is sequentially joined and connected.

The liner 1 is housed in the skin plate 11 while being supported by front and rear push jacks 24 and 25. During excavation by the tunnel excavator 10, the liner 1 is incorporated in the skin plate 11 by extending the sliding jack 26 in synchronization with the extension of the propulsion jack 18. And skin plate 11
When an excavated wall portion T ′ in which a crack or a collapse has occurred is observed from inside through the slit 30, the excavated wall portion T ′ relatively moves rearward according to the excavation of the tunnel excavator 10 and moves from the rear end of the skin plate 11. If the operation of the sliding jack 26 is stopped when exposed to the rear, the sliding frame 23 moves relatively backward on the beam body 14 and is sent out from the rear end of the skin plate 11 to the tunnel excavation wall T. It is.

When the rear half of the liner 1 is sent out from the skin plate 11 to the tunnel excavation wall T side, the rear push-up jack 25 on the sliding frame 23 is extended as shown in FIGS. As a result, the rear half of the liner 1 is lifted upward, and the outer peripheral surface of the rear end thereof is brought into contact with the excavated wall portion T 'where a crack or the like is formed, thereby preventing the rock from collapsing. After pushing up the rear end of the liner 1, the tunnel excavator 10
Digs further and the first half of liner 1 is skin plate 11
Is relatively sent out into the tunnel excavation wall T from
This time, by extending the front push-up jack 24 on the sliding frame 23, the upper peripheral portion of the liner 1 is brought into close contact with the above-mentioned excavated wall portion T 'of rocky material having cracks, etc. Support the excavated wall part T '.

During the delivery of the liner 1 to the tunnel excavation wall T side, the next small-diameter liner 1 is assembled in the skin plate 11 using an erector. And
The sliding frame 23 moved rearward from the skin plate 11 to support the excavated wall portion T 'where a crack or the like has occurred is returned into the skin plate 11 by extending the sliding jack 26, and the jack is pushed up and down. 24 and 25 are used to hold the next bad excavation wall portion T '.

In order to bring the liner 1 into full contact with the excavated wall portion T ', a jack is inserted between the front ends of the joint plates 1c, 1c of the adjacent support pieces on the lower peripheral side of the liner 1 as described above.
The entire liner is expanded by extending it with the interposition of 37, and a key piece (not shown) or the like is interposed between the joints 1c, 1c separated from each other, or fixed at a fixed distance by bolts. When the liner 1 is held by the front and rear push-up jacks 24 and 25 of the sliding frame 23, the liner 1 is built in the skin plate 11 while holding only the upper peripheral portion of the liner 1, and the tunnel excavation wall surface is provided. After the upper peripheral portion is brought into close contact with the excavated wall surface portion T ′ where the cracks and the like are generated by being sent out to the T side, a lower peripheral side support piece may be assembled to form a ring-shaped support body.

In any of the above methods, the jack 22 for extrusion or the jack 26 for sliding is used for sending out the liner 1 from the inside of the skin plate 11 to the tunnel excavation wall T side. Alternatively, it may be performed by pulling from the existing support side.

When the tunnel excavator 1 excavates a tunnel, the rear grippers 17, 17 are moved to the tunnel excavation wall T.
Then, the rear support 16 is contracted to separate from the bottom surface of the tunnel excavation wall T, and then the propulsion jack 18 is extended to support the reaction force on the tunnel wall 2 via the rear gripper 17. With the front gripper 15 in sliding contact with the excavation wall T, the cutter plate 13
I will continue to excavate. After excavation of the tunnel of a certain length, the front gripper 15 is firmly pressed against the excavation wall 2 and the rear support 16 is extended to be supported on the bottom surface of the excavation wall 2 and the rear gripper 17 is contracted. The rear gripper 17 is advanced along the beam member 14 to the next crimping position by contracting 18.

[0036]

As described above, according to the method for supporting a tunnel excavation wall according to the present invention, a liner is assembled in a skin plate of a tunnel excavator. It is possible to safely and efficiently assemble the liner without any influence on the surface of the tunnel excavation wall. Is exposed to the rear of the skin plate according to the excavation of the tunnel excavator, the liner contained in the skin plate is sent backward from the skin plate and adheres to the tunnel excavation wall portion to support the excavation wall portion. If the properties of the tunnel excavation wall are good, do not send the liner to the tunnel excavation wall Because it is to be built into the rate, it is possible to reduce the material cost by supporting the liner only on the poorly excavated wall part where cracks and collapses have occurred, and to support the tunnel excavation wall Can greatly reduce the working time.

When the liner is sent from the skin plate to the tunnel excavation wall surface, the upper peripheral portion of the liner is brought into close contact with the upper wall surface of the excavation wall surface. The tunnel excavation wall surface immediately after the skin plate is supported with almost no gap between the outer peripheral surface of the support and the outer peripheral surface of the support body, and the collapse of the bedrock and the fall of the skin can be reliably prevented.

As means for bringing the liner into close contact with the tunnel excavation wall surface, the liner can be reliably delivered by expanding the liner from the rear end of the skin plate while increasing the diameter of the liner. As described in 3, the upper peripheral portion of the liner can be easily and surely brought into close contact with the upper peripheral wall surface of the tunnel excavation wall surface by pushing up the portion fed from the rear end of the skin plate.

According to the fourth aspect of the present invention, a support having a rock fall prevention member such as a wire mesh stretched only on the upper peripheral side of the tunnel excavation wall surface where rock fall or surface fall may occur. Since it is formed on the body part, it is possible to reduce material costs and improve workability.

[Brief description of the drawings]

FIG. 1 is a simplified longitudinal side view of a state in which a support is formed by a tunnel excavator provided with a means for feeding while expanding a liner,

FIG. 2 is a simplified longitudinal sectional side view of a state in which a support is formed by a tunnel excavator having a means for pushing out and sending out a liner,

FIG. 3 is a perspective view of a support piece on which a collapse prevention member is stretched;

FIG. 4 is a perspective view of a support piece having a collapse prevention member stretched over a part thereof;

FIG. 5 is a perspective view of a support piece without a collapse prevention member,

FIG. 6 is a front view showing a state where the rotary type liner assembling erector is assembled.

FIG. 7 is a simplified vertical sectional front view showing a state where the diameter of the liner is expanded;

FIG. 8 is a simplified vertical sectional front view showing a state where the liner is supported by front and rear jacks.

FIG. 9 is a simplified vertical sectional front view showing a state where the liner is pushed up.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liner 1A-1c Support piece 10 Tunnel excavator 11 Skin plate 21 Swivel liner assembling erector 22 Liner extrusion jack 23 Sliding frame 24, 25 Push-up jack 27 Collapse prevention member T Tunnel excavation wall surface

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Kazuhiro Kano 2-2-2 Matsuzaki-cho, Abeno-ku, Osaka-shi Okumura Gumi Co., Ltd. (56) References JP-A-62-133299 (JP, A) Patent 3022282 (JP) , B2) (58) Field surveyed (Int.Cl. ⁷ , DB name) E21D 11/14 E21D 9/10

Claims (4)

(57) [Claims] 1. A liner composed of a plurality of rectangular frame-shaped support pieces curved in the circumferential direction of a tunnel in a skin plate of a tunnel excavator. Judge the properties, and if the properties are poor, when the wall of the tunnel excavation is exposed behind the skin plate as the tunnel excavator excavates, send out the liner built into the skin plate relatively backward from the skin plate. The excavation wall portion is supported by contacting with the tunnel excavation wall portion, and when the properties of the tunnel excavation wall surface are good, excavation should be performed with the liner built into the skin plate without sending out the liner to the tunnel excavation wall surface. Characteristic method of supporting tunnel excavation wall surface. 2. When the rear portion of the liner is relatively sent out from the rear end of the skin plate, the rear portion is increased in diameter, and the front portion sequentially sent out is increased in diameter so as to be in close contact with the tunnel excavation wall surface. The method of supporting a tunnel excavation wall surface according to claim 1. 3. When the rear portion of the liner is relatively sent out from the rear end of the skin plate, the rear portion is pushed up, and the front portion that is sequentially sent out is pushed up to make close contact with the tunnel excavation wall surface. 2. The method for supporting a tunnel excavation wall surface according to 1. 4. The support of a tunnel excavation wall according to claim 1, wherein the rocker has a rock fall prevention member stretched at least on an outer peripheral surface of an upper half portion of the liner. Method.