JPH0774585B2 - Tunnel excavation method and prelining construction device - Google Patents

Description

The present invention relates to a method of forming a tunnel by constructing a prelining along the outer periphery of a tunnel cross-sectional shape and excavating the ground surrounded by the prelining to form a tunnel. , A device for constructing the pre-lining.

[Conventional technology]

Conventionally, the method of spraying concrete on the excavated wall surface after excavating the tunnel space has been widely used for tunnel lining, but the loosening of the ground that occurs between tunnel excavation and lining is suppressed. If the ground is soft and unconsolidated ground or there is groundwater, it is extremely dangerous because the face collapses and the ground skin falls off during the lining work, and the ground is stable. It is difficult to let

Furthermore, when concrete is sprayed on the tunnel wall,
There is a problem in that a large amount of bounce and dust are generated, and loss of materials and deterioration of the working environment cannot be avoided.

Further, such a method of applying a lining after excavating a tunnel can be applied to a case where the tunnel has a small cross section, but is difficult to apply to excavating a tunnel having a large cross section.

Therefore, from the outer peripheral edge of the tunnel of the face to the ground in front,
An arch-shaped slot along the outer circumference of the tunnel is excavated to a desired depth, and the slot is filled with concrete to form a lining (pre-lining) before tunnel excavation, and then the ground surrounded by the concrete is excavated. A method of excavating a tunnel by repeating the work of doing was developed,
In this way, as the excavation device for the slot in the construction method,
BACKGROUND ART Conventionally, a device has been developed so that multiple earth augers are connected in a parallel state and a circular excavation cross section by each earth auger can be continuously excavated to form a slot having a constant width.

[Problems to be Solved by the Invention]

However, in such a multiple earth auger, the width of the slot to be excavated is always constant, and therefore, even if the slots are drilled in a state where the adjacent slots communicate with each other on the face of the face, Since the digging direction is formed in a divergent shape so as to incline in the diameter expansion direction of the tunnel, there will be a gap between adjacent groove holes on the groove hole tip side, and concrete will be inserted in the groove holes. If the ground on the inner side of the ground is excavated after filling, there are problems that the soft ground collapses from the gap portion and spring water is generated.

In addition, the shape of the slot hole excavated by the multiple earth auger is a shape in which the circular holes by the adjacent earth augers are partly overlapped, that is, the peripheral wall has an uneven shape, so the excavation area is relatively small. There is a problem that an effective area for tunnel lining becomes small and more material than necessary is required to obtain a desired lining thickness.

Further, in order to eliminate the occurrence of the gap between the groove hole tip portions as described above, it is sufficient to overlap a part of the groove holes adjacent to each other on the face face side. The joints in the cross-sectional direction between the parts are point-joint with a circular cross-section, and the rigidity of the lining is reduced and the water stoppage is insufficient, and the lining is intermittent at regular intervals in the length direction of the tunnel. Since it is provided continuously and is not continuous in a series, there has been a problem that the waterproofness is further insufficient.

Furthermore, every time a lining of a fixed length is formed, the work of excavating the ground surrounded by the lining is alternately repeated to dig a tunnel. Therefore, a tunnel of a fixed length must be excavated. If you can't do the next lining,
There was a problem that work efficiency was poor.

An object of the present invention is to provide a tunnel excavation method capable of solving such a problem and a prelining construction device used for the method.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the tunnel excavation method of the present invention constructs a tunnel in the longitudinal direction of the planned tunnel at the lower ends of both sides of the tunnel to be excavated, and tunnels to the planned tunnel starting end face side of the both tunnels. A pre-lining construction device having a constant thickness along the outer circumference of the cross section is arranged so as to straddle the tunnels, and both lower end portions of the pre-lining construction device are installed in both tunnels so as to be movable in the length direction of the tunnel. Then, while excavating a groove hole of a constant thickness along the outer circumference of the tunnel with an excavator provided at the front end of the prelining construction device while moving the prelining construction device in the length direction of the tunnel, The concrete is placed in the hole to construct the pre-lining, and this pre-lining is constructed over the entire length of the planned tunnel and is surrounded by the pre-lining. It is characterized in that drilling.

Further, as the pre-lining construction device used for the tunnel excavation method, the lower end portions on both sides of the tunnel to be excavated straddle the two side tunnels constructed along the length direction of the planned tunnel, A hollow shield frame having a constant thickness along the outer circumference of the tunnel cross section, which is movable along the guide shaft, and a groove hole having a constant thickness, which is arranged at the front end of the hollow shield frame and has a constant thickness, in the front ground of the shield frame. An excavator,
The earth and sand discharge port opened at the lower end of the shield frame, the concrete pouring path for supplying and placing concrete into the rear end opening of the shield frame, and the back and forth movable placement in the rear part of the shield frame were placed. It is characterized by comprising a press ring for retaining the shape of concrete and a propelling jack for moving the press ring back and forth.

[Action]

A tunnel will be built along the lower ends of both sides of the tunnel to be excavated, and a tunnel-shaped prelining construction device will be straddled between the tunnels on the starting side of the planned tunnel. It is installed in such a state that both lower ends are movably installed in both sides of the tunnel in the longitudinal direction of the tunnel.

After that, the excavator disposed at the front end of the hollow shield frame of the prelining construction device excavates the ground in front, and the prelining construction device is advanced to form a tunnel-shaped slot.

The excavated earth and sand is discharged through the shield frame from the lower end of the opening of the shield frame into the guide pit, and is carried out of the mine by a transport vehicle or the like.

The advance of the pre-lining construction device is performed by a propulsion jack by taking a reaction force to the press ring side arranged at the rear end portion of the shield frame, and the back of the shield frame is inserted into the groove of the propulsion mark of the pre-lining construction device. The concrete is cast through the end opening, and the propelling jack is expanded and contracted in accordance with the casting, thereby constructing the pre-lining portion with a length of one excavation.

This prelining portion, a step of excavating a slot of a constant length by an excavator disposed at the front end of the prelining construction device, a step of propelling the shield frame of the prelining device in the slot, and a shield frame The step of placing concrete in the groove hole of the propulsion mark is repeated to form successively, and the arch-shaped pre-lining that is continuous in the length direction of the planned tunnel is built.

Then, following the construction of the prelining, the ground surrounded by the prelining is excavated and removed to form a tunnel.

〔Example〕

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a tunnel (B) constructed along the tunnel length direction at the lower ends of both sides of a planned tunnel (T) where a prelining construction device (A) is to be excavated. (B) shows a state in which the pre-lining construction device (A) is arranged so as to straddle between the two. As shown in FIGS. 1 to 3, the pre-lining construction device has an arch shape along the outer circumference of the tunnel cross section. Curved inner and outer curved plates with a fixed length and width (1
a) (1b) are placed opposite to each other with a certain thickness interval, and rectangular bottom plates (1c) (1c) are provided over the entire length between the lower ends of the inner and outer curved skin plates (1a) (1b). A hollow arch-shaped shield frame (1) formed by integrally connecting, an excavator (2) arranged in the front end opening of the shield frame (1), and a shield frame (1) are formed. A soil discharge port (3) opened at both lower ends of the front end portion of the inner curved skin plate (1b), and a press ring (4) arranged in the rear portion of the shield frame (1) so as to be movable back and forth.
It is composed of a propulsion jack (5) for moving the press ring (4) back and forth and an injection path (6) for supplying concrete to the rear side of the press ring (4).

This configuration will be described in more detail. As shown in FIGS. 3 to 6, there is a certain distance from the front end of the inner and outer curved skin plates (1a) (1b) in the front end of the shield frame (1) and the forward movement. Front and rear rail bodies (7) on the surface facing the rear part
(8) is projected in the circumferential direction, and these front and rear rail bodies (7)
A moving casing (11) in which a cutter driving motor (9) and a traveling hydraulic motor (10) are installed and installed in the space between (8) is arranged in front of and behind the moving casing (11). The moving casing (11) is guided along the rail bodies (7) and (8) while the guide rollers (12) rotatably supported in four directions inside and outside are brought into contact with and supported by the facing surfaces of the rail bodies (7) and (8). And is movable in the circumferential direction within the front end of the shield frame (1).

At the front end of the rotary shaft of the cutter driving motor (9) installed in the center of the moving casing (11), a large number of excavating bits (2b) are projected on the peripheral surface from the front end of the shield frame (1). ) (2b) ... is fixed to the cutter (2a) to form the excavator (2).

The traveling motors (10) (10) of the moving casing (11) are arranged on both sides of the cutter driving motor (9), and the gear (10a) fixed to the rotary shaft of the moving casing (11) is attached to the upper frame of the moving casing (11). The inner surface of the outer curved skin plate (1a) of the shield frame (1) is a small-diameter sprocket wheel (13c) that is meshed with a gear (13a) that is rotatably supported on the lower surface and is fixed coaxially (13b). The moving casing (11) is configured to move in the circumferential direction within the front end portion of the shield frame (1) by being engaged with the roller chain (14) that is fixed to the circumferential direction on the drive frame and driven by the traveling motor (10). There is.

From the opening to the earth and sand discharge port (3) (3), a tunnel (B)
A slanting chute (15) is arranged inward, and a suspension chain (1) supporting the tip of this slanting chute (15) is provided.
6) has its upper end suspended along the ceiling surface of the tunnel (B) movably in the longitudinal direction.

Further, the rear end opening of the shield frame (1) is formed in the concrete pouring opening (17), and the press ring (4) disposed in the rear part so as to be movable back and forth has a hollow rectangular cross section. It is formed in a front arch shape along the curved hollow cross section of the shield frame (1), and the propulsion jacks (5) (5) are provided inside the shield frame (1) in the front part of the press ring (4). ) (5) are arranged at appropriate intervals in the circumferential direction, and the front end of each propulsion jack (5) is connected to the support frame plate (1d) fixed in the shield frame (1) and The tip of the rod is connected to the press ring (4), and the press ring (4) is slid back and forth within the rear part of the shield frame (1) by the operation of these propulsion jacks (5).

Furthermore, the injection part (6) for supplying concrete into the rear end of the shield frame (1) is connected to the lower ends of both sides of the rear part of the shield frame (1) exposed in the tunnels (B) and (B). It is formed by an injection tube. This injection channel (6) is a concrete pouring port (17) on the rear side of the press ring (4).
Although it may be directly communicated with the press ring (4), a fixed injection pipe is provided in the press ring (4) in the circumferential direction, and the injection ports branched from a plurality of the fixed injection pipe are pressed to the press ring (4). It is also possible to open the rear side from the rear surface and to connect the flexible injection pipe to the lower end of the fixed injection pipe through the lower end of the shield frame (1) so as to communicate therewith.
Further, as shown in FIG. 12, a working pit (C) is previously excavated in the center of the upper curved portion of the planned tunnel (T) in the length direction of the tunnel, and a concrete pouring port (17) is pierced through the working pit (C). ), Concrete may be supplied to the central portion through an appropriate injection pipe.

The shield frame (1) has bottom plate on both sides (1c) (1c)
A plurality of wheels (18) running on rails (19) (19) laid on the side walls (D) (D) built on the outer side of the guide shaft (B) (B). They are mounted at appropriate intervals in the vertical direction.

(22) is a hose reel attached to the lower end of one side of the shield frame (1). The hydraulic hose wound around the hose reel (22) is connected to the hydraulic motor (9) (1) inside the shield frame (1).
0) or the like via a hose introducing roller (23) arranged in the frame.

Explaining the method of constructing the prelining and the method of constructing the tunnel by using the prelining construction device configured as described above, first, the starting shaft (E) and the reaching shaft (F) are provided at the start end side and the end side of the planned tunnel. And the guide shafts (B) and (B) are formed between these compatible shafts (E) and (F) by a known tunneling method. At this time, the working pit (C) is also formed if necessary.

Next, the prelining construction device (A) is arranged on the side of the starting shaft (E), and the rails (19) (19) on the side walls (D) (D) extending into the starting shaft (E) at the lower ends of both sides thereof are arranged. ) Installed over the wheels (18).

After that, an excavator (2) arranged at the front end of the hollow arched shield frame (1) of the prelining construction device (A) is used to form a slot (G) along the outer periphery of the tunnel cross section in the front ground. Excavate.

When the cutter driving motor (10) in the moving casing (11) is driven, the slot (G) rotates the cutter (2a) protruding from the front end of the opening of the shield frame (1) to rotate the cutter (2a). When the traveling hydraulic motor (10) is driven while drilling a hole corresponding to the diameter of the sprocket wheel (13a) rotates through the meshing gears (10a) (13a), the outer skin plate of the shield frame (1) is rotated. Excavation is performed by moving the casing (11) in the circumferential direction with the rails (7) and (8) as guides in the opening end of the shield frame (1) while meshing with the roller chain (14) provided on the inner surface. To be done.

Thus, the shield casing (1) is moved forward while reciprocating the movable casing (11) in the arch direction in the front end portion of the shield frame (1), whereby the arch-shaped slot ( G) is to be excavated,
Until the shield frame (1) is completely immersed in the ground, the shield frame (1) is propelled by applying a reaction force to the inner wall of the starting shaft (E) and using an appropriate pressing jack or the like. .

When the groove shaft (G) is excavated forward from the starting shaft (E) to the length of the shield frame (1) or more, the opening end of the groove hole (G) is appropriately closed by a frame or the like, and the propulsion jack. Concrete is poured into the rear end of the shield frame (1) through the concrete pouring path (6) in a state where (5) is contracted and the press ring (4) is retracted.

After that, when the propulsion jack (5) is extended, the press ring (4) moves to the rear side and moves from the concrete placing port (17) of the shield frame (1) to the groove of the propulsion mark of the shield frame (1). The concrete filled in (G) is compressed and crushed, the pre-lining part (P ₁ ) is built, and the shield frame (1) is moved forward by taking a reaction force to the pre-lining part (P ₁ ). However, the groove hole (G) is excavated by the rotation and movement of the excavator (2) in the circumferential direction.

The excavated earth and sand fall from the front end of the shield frame (1) to both sides, and are thrown from the discharge port (3) into the carrier (20) waiting in the tunnel (B) by the inclined chute (15). And is carried out to the side of the starting shaft (E).

Thus, the shield frame (1) with the propulsion jack (5)
The process of excavating the groove hole (G) in the front ground by the excavator (2) according to the advance of the, and placing the concrete in the groove hole (G) of the propulsion mark of the shield frame (1) and prelining The process of building the part (P ₁ ) is continuously performed to build the prelining (P) between the starting shaft (E) and the reaching shaft (F).

A tunnel (T) is formed by excavating and removing the ground surrounded by the pre-lining (P) after the pre-lining (P) has been built or after the pre-lining (P) is being built. To do.

The shield frame (1) is, as shown in FIGS.
The excavator (2) is divided into two parts, a front end part in which the excavator (2) is arranged and a rear part following it, and both frame parts are connected by a plurality of center folding jacks (21). It is provided in order to direct the excavation direction of the groove hole (G) in the correct direction, and the groove hole (G) can be excavated without dividing.

Further, in the above embodiment, the excavator (2) has the structure in which the cutter (2a) is provided in the moving casing (11) that reciprocates in the circumferential direction within the front end opening of the shield frame (1). The groove hole (G) can be excavated even if it is a fixed type without adopting such a moving excavation mechanism.

FIG. 8 to FIG. 11 show an example thereof. Instead of the excavator (2), the earth augers (24) (24) are provided in the front opening of the shield frame (1) at small intervals in the circumferential direction. ) ・ ・ ・ (2
4) A large number of 4) are arranged side by side to form an excavator, and each earth auger (24) has a bit (24a) at the tip and an outer periphery in a rectangular tubular box (25) with a hollow rectangular cross section. The screw part (24b) and the shield frame (1) are rotatably accommodated in a state of protruding from the front end of the shield frame (1), and are rotated by a drive motor (26) installed in the rear end of the box (25). The rear end of the box (25) is connected to the rod tip of the pressing jack (27) arranged in the shield frame (1) so that the expansion and contraction of the pressing jack (27) moves the box (25) back and forth. There is. Further, the tip surfaces of these boxes (25) are formed on the digging edge, and the adjacent boxes (25, 25) are slidably and closely engaged with each other.

The other structure is the same as that of the above embodiment.

The excavator constructed in this way can be used for each pressure jack (27).
Is operated to move the box (25) in the front-rear direction to excavate an arch-shaped groove hole (G) of an appropriate depth in the front ground, and a shield frame is provided in this groove hole (G). The (1) is pushed by the propulsion jack (5) and the concrete is placed as described above after the shield frame (1) is propelled to build the prelining (P).

In such a pre-lining construction device, the excavator (2) or the excavation device (24) is used as an upper excavator, and a lower excavator (28) is provided under the excavator (28) as shown in FIGS. 8 to 11.
May be provided.

Such an excavator (28) has the same structure as the moving excavator (2) on the inner peripheral surface of the inner skin plate (1b) of the shield frame (1), that is, the inner periphery of the skin plate (1b). A drive motor (30) is installed in a movable casing (29) arranged so as to be movable in the circumferential direction along the surface, and the cutter (31) that protrudes forward from the casing (29) by the drive motor (30). ) May be configured to rotate, or a structure in which a drill bit and an earth auger having a screw portion following the drill bit are arranged side by side in the circumferential direction may be used.

By providing the lower end excavator (28) in this way, the excavator (28) excavates the arch-shaped working space (32) along the inner peripheral surfaces of the shield frame (1) and the prelining (P). Through this working space (32), concrete can be supplied into the central part of the rear end of the shield frame (1) through an appropriate supply pipe, or maintenance and repair of the machine can be performed. The subsequent tunnel excavation work can be performed efficiently.

〔The invention's effect〕

As described above, according to the tunnel excavation method of the present invention, first, a tunnel is constructed at the lower ends of both sides of the tunnel to be excavated along the lengthwise direction of the planned tunnel, and the planned tunnel starting end surface side of the two-sided tunnel is constructed. A prelining construction device having a constant thickness along the outer circumference of the tunnel cross section is installed across the tunnels and moved in the length direction of the tunnel to build the prelining in the ground. Therefore, a pre-lining having the same cross-sectional shape as the pre-lining construction device and having a constant thickness can be continuously constructed along the outer periphery of the planned tunnel, and a large-sized pre-lining can be easily formed. The lining is constructed over the entire length of the planned tunnel, and the ground surrounded by the inner surface is excavated to form the tunnel. Since a series of pre-lining covering the entire cross section can be performed after or after the construction, smooth and efficient excavation work is possible, and the face is stable and the displacement of the tunnel is reduced, resulting in surface subsidence or It is possible to reduce the influence on the intermediate structure.

Furthermore, since it is possible to excavate a large cross section, tunnel excavation can be performed by a large machine, and excavation work efficiency is further improved.

In addition, the device for constructing the pre-lining before the tunnel excavation is constructed so that the lower end portions of both sides of the tunnel to be excavated are straddled between the both side tunnels constructed in the longitudinal direction of the planned tunnel. A hollow shield frame having a constant thickness along the outer periphery of the tunnel cross section that is movable along the mine,
An excavator installed at the front end of this hollow shield frame to excavate a groove hole of a certain thickness in the front ground of the shield frame, a sediment discharge port opened at the lower end of the shield frame, and a concrete inside the rear end opening of the shield frame. A concrete pouring path for supplying and pouring, and a press ring for arranging the placed concrete movably arranged in the rear part of the shield frame so as to be rammed,
Since this pre-lining is composed of a propulsion jack that moves back and forth, it is possible to accurately excavate a groove along the outer circumference of the tunnel cross section in the front ground by propelling the shield frame while operating the excavator. The shield frame is propelled by extending the propulsion jack by applying a reaction force to the press ring side, so that the shield frame can be propelled in the ground in a self-propelled manner. The space can be automatically dropped to the earth and sand discharge port, and can be discharged into the guide shafts on both sides through the discharge port, and can be smoothly discharged by a carrier vehicle or the like.

Furthermore, because the concrete is placed through the rear end opening of the shield frame in the groove of the propulsion mark of the shield frame, a pre-lining with a certain thickness can be continuously constructed, and It is possible to build a highly accurate pre-lining that has a large size and exhibits a reliable waterproofing property.

Further, since this pre-lining can be continuously applied by the above-mentioned device, the excavation work of the tunnel can be performed after the construction of the pre-lining as described above.

[Brief description of drawings]

The drawings show an embodiment of the present invention. Fig. 1 is a simplified rear view of a state in which a pre-lining construction device is arranged between both sides of a tunnel, Fig. 2 is a simplified longitudinal side view thereof, and Fig. 3 is a plan view. FIG. 4 is a vertical cross-sectional side view of the lining construction device, FIG. 4 is a cross-sectional view of the mobile excavator portion, and FIGS. 5 and 6 are X- in FIG. 4, respectively.
Fig. 7 is a vertical sectional side view in X-ray and Y-Y line, Fig. 7 is a partially cutaway simplified perspective view in which a prelining and a tunnel are provided between vertical shafts, and Fig. 8 is a prelining in which another excavating device is arranged. Simplified rear view for explaining the prelining construction method by the construction device, FIG. 9 is a simplified vertical sectional side view thereof, FIG. 10 is a vertical sectional side view of the excavating device portion, and FIG. 11 is a vertical sectional side face of the concrete placing portion. Fig. 12 is a vertical sectional view of the built tunnel. (1) …… shield frame, (2) …… excavator, (3) ……
Sediment discharge port, (4) …… Press ring, (5) …… Propulsion jack, (6) …… Concrete injection path, (17) ……
Concrete pouring mouth, (A) …… Pre-lining construction device, (T) …… Planning tunnel, (B) …… Guide shaft, (G)
…… Slot, (P) …… Pre-lining.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 999999999 Maeda Construction Industry Co., Ltd. 2-1026 Fujimi, Chiyoda-ku, Tokyo (72) Inventor Yoshio Adachi 1 Asahi, Tsukuba, Ibaraki Prefectural Government Civil Engineering Research Institute ( 72) Inventor Toshinori Mizutani, Asahi 1 Tsukuba, Ibaraki Prefecture, Asahi, Civil Engineering Research Institute, Ministry of Construction (72) Inventor Shigeru Inano 1 Asahi, Tsukuba, Ibaraki Prefecture, Civil Engineering Research Institute, Ministry of Construction (72) Inventor, Mamoru Konishi Osaka, Osaka 2-2-2 Matsuzaki-cho, Abeno-ku Okumura-gumi Co., Ltd. (72) Masayuki Hamano 3-1-1 Higashikawasaki-cho, Chuo-ku, Kobe, Hyogo Prefecture Kawasaki Heavy Industries Ltd. Kobe factory (72) Inventor Yukio Kakiuchi Tokyo 2-1-1 Tsukudo-cho, Shinjuku-ku, Tokyo Kumagai Gumi Co., Ltd. (72) Inventor Sadahiko Takamori 2-10-2 Fujimi, Chiyoda-ku, Tokyo No. 6 in Maeda Construction Industry Co., Ltd. (56) Reference JP-A-3-257292 (JP, A) JP-A-3-257293 (JP, A) JP-A-3-257297 (JP, A)

Claims (2)

[Claims] 1. A pre-lining having a constant thickness along the outer circumference of the tunnel cross section on the side of the planned tunnel starting end face of both sides of the tunnel at the lower ends of both sides of the tunnel to be excavated. The building equipment is arranged in a state of straddling between the tunnels, and the lower end portions on both sides of the prelining building equipment are movably installed in the tunnels on both sides in the tunnel length direction. While moving in the length direction of the tunnel, excavating a slot having a constant thickness along the outer circumference of the tunnel by an excavator provided at the front end of the prelining construction device, and placing concrete in the slot for prelining. A tunnel excavation method, characterized in that the pre-lining is constructed over the entire length of the planned tunnel and the ground surrounded by the pre-lining is constructed. 2. A tunnel in which the lower ends of both sides of a tunnel to be excavated straddle between two side tunnels constructed along the length direction of the planned tunnel and the lower ends of both sides of the tunnel are movable along the respective tunnels. A hollow shield frame having a constant thickness along the outer circumference of the cross section, an excavator disposed at the front end of the hollow shield frame for excavating a slot of a constant thickness along the outer circumference of the tunnel cross section in the front ground of the shield frame, and a shield The earth and sand discharge port opened at the lower end of the frame, the concrete pouring path for supplying and placing concrete into the rear end opening of the shield frame, and the concrete that is placed in the rear part of the shield frame so as to be movable back and forth. A prelining construction device comprising a press ring that retains the shape of the above and a propulsion jack that moves the press ring back and forth.