JP2014156689A - Pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe having a double-pipe structure, capable of maintain a non-drainage structure state during propulsion to realize a sealed propulsion method to prevent collapse of the natural ground, and capable of being in a drainage structure state after the end of the propulsion to perform drainage of the natural ground.SOLUTION: A pipe includes an outer pipe 31 having a circular cross section, and an inner pipe 32 having a circular cross section, each of which has a plurality of through-holes 35 penetrating through the pipe formed therein. An outer diameter dimension of the inner pipe 32 and an inner diameter dimension of the outer pipe 31 are set so that only the inner pipe 32 can be rotated. The rotation of the inner pipe 32 using the central axis of the inner pipe 32 as a rotation center allows the pipe to be set to a non-drainage structure state and a drainage structure state. In the through-holes 35 of at least one of the inner pipe 32 and the outer pipe 31, filters 36 allowing water to pass and preventing sediments from passing are installed, respectively. The pipe has a double-pipe structure capable of maintain the non-drainage structure state during propulsion to realize a sealed propulsion method, and capable of being in the drainage structure state after the end of the propulsion.

Description

  The present invention relates to a pipe with a water draining function installed on a natural ground by a propulsion method.

  In tunnel construction, it is known to install a pipe for draining natural ground by a propulsion method (see Patent Document 1).

JP 2002-295180 A

The drainage pipe described above has a configuration in which a drainage hole is only formed in the pipe (see the first cylinder 6 in Patent Document 1). When such a perforated pipe is used, the closed type propulsion method cannot be realized. For example, when a fault crush zone exists in the middle of propelling a natural ground and the fault crush zone is broken through. There is a possibility that water of high water pressure will flow into the pipe at once through the hole of the pipe being propelled and the ground will collapse.
The present invention can maintain a non-drainage structure state during propulsion, thereby realizing a closed type propulsion method and preventing collapse of the natural ground, and after completion of the propulsion, it can be in a drainage structure state to drain the natural ground. Providing a double tube structure that can be used.

  According to the pipe according to the present invention, the pipe is installed in the natural ground by the propulsion method, and includes a circular outer cross-section in which a plurality of through-holes penetrating inside and outside the pipe are formed and a circular cross-section inner pipe. The outer diameter of the inner tube and the outer tube so that only the inner tube can be rotated around the central axis of the inner tube while the outer peripheral surface of the inner tube is in contact with the inner peripheral surface of the outer tube. The inner diameter is set and the inner tube is rotated about the center axis of the inner tube as the center of rotation, so that the center of each through-hole of the inner tube and the center of each through-hole of the outer tube coincide with each other. The drainage structure state in which the hole and the through hole of the outer pipe communicate with each other, and the opening on the outer peripheral surface side of each through hole of the inner pipe is blocked by the inner peripheral surface of the outer pipe, and The inner peripheral surface side opening can be set to a non-drainage structure state closed by the outer peripheral surface of the inner pipe, and in each through hole of at least one of the inner pipe and the outer pipe Providing a structure with a filter that allows water to pass through without passing through the earth and sand, it is possible to realize a closed-type propulsion method in a non-drainage structure during propulsion, and a double-pipe structure that can be drained after completion of propulsion. The inside can maintain a non-drained structure, which can realize a closed-type propulsion method and prevent collapse of the natural ground, and after completion of the promotion, it can be in a drained structure and drain the natural ground.

It is a perspective view which shows a pipe | tube, Comprising: (a) shows the non-drainage structure state during propulsion, (b) shows the drainage structure state at the time of draining. Sectional drawing of the inner pipe (outer pipe | tube) which comprises a pipe | tube. The figure which shows the process of the construction method of a mountain tunnel. Cross section of a mountain tunnel.

As shown in FIG. 1, the pipe 3 installed in the natural ground by the propulsion method can maintain the undrained structure state (see FIG. 1 (a)) during the propulsion, thereby realizing the closed propulsion method. The pipe has a double pipe structure that can prevent collapse and can be drained (see FIG. 1 (b)) after completion of propulsion to drain the natural ground.
The tube 3 includes an outer tube 31 having a circular cross section and an inner tube 32 having a circular cross section, and the central axis of the outer tube 31 and the central axis of the inner tube 32 provided inside the outer tube substantially coincide with each other. That is, it is a double tube having a configuration in which the outer tube 31 and the inner tube 32 are arranged coaxially. For example, only the inner tube 32 can be rotated around the central axis of the inner tube 32 while the outer peripheral surface of the inner tube 32 and the inner peripheral surface of the outer tube 31 are in contact with each other. The diameter dimension and the inner diameter dimension of the outer tube 31 are set. A plurality of through holes 35 penetrating into and out of the tube are formed in the tube wall of each tube 31; 32. The plurality of through holes 35 are provided, for example, so that the centers of the through holes 35 are positioned on a plurality of lines parallel to the central axis of the tube, and penetrate through the circumferences of a plurality of circles orthogonal to the central axis of the tube. It is provided so that the center of the hole 35 is located.
The tube 3 rotates the inner tube 32 around the central axis of the inner tube 32, so that the center of each through hole 35 of the inner tube 32 coincides with the center of each through hole 35 of the outer tube 31. The drainage structure state in which the through hole 35 of the inner pipe 32 and the through hole 35 of the outer pipe 31 communicate with each other (see FIG. 1B), and the outer peripheral surface side opening of each through hole 35; 35. Is closed by the inner peripheral surface of the outer tube 31 and the inner peripheral surface side opening of each through hole 35; 35... Of the outer tube 31 is closed by the outer peripheral surface of the inner tube 32 (see FIG. 1 (a)).
As shown in FIG. 1; FIG. 2, a filter 36 such as a drain material that allows only water to pass through without passing through earth and sand is installed in each through hole 35 of at least one of the inner tube 32 and the outer tube 31. Has been. That is, at least one of the inner tube 32 and the outer tube 31 is configured as a water permeable tube in which a filter 36 that allows only water to pass through without passing through the earth and sand is provided in the through hole 35.
In addition, when the filter 36 is provided in the through hole 35 of the outer pipe 31, since the natural ground 5 and the filter 36 of the outer pipe 31 are easy to contact when the pipe 3 is installed in the natural ground 5, When only one of the outer tubes 31 is a water permeable tube provided with the filter 36, the inner tube 32 is preferably a water permeable tube.

  A pipe installation device 10 for installing the pipe 3 in the natural ground 5 by the propulsion method is a device that realizes a closed type propulsion method having a face stabilization function and an earth and sand carrying out function during excavation, and is shown in FIG. Thus, the pipe 3, the excavating means 11 provided on the leading side of the pipe 3, and the propulsion means 12 provided on the rear end side of the pipe 3 to press the pipe 3 forward are provided.

  The excavating means 11 is, for example, a cutter head or an auger that is provided on the leading side of the tube 3 and rotates around the central axis of the tube 3 as a rotation center.

  The propulsion unit 12 includes, for example, a jack 13 as a pressing machine that pushes the rear portion of the tube 3 and a pressure bearing body 14 that serves as a reaction force receiving the reaction force applied to the jack 13 when pushing the rear portion of the tube 3. It is a configuration.

  According to the pipe 3 with a water draining function that is installed in the natural ground 5 by the propulsion method of the embodiment, when it is propelled to the natural ground 5 by the pipe installation device 10, it is possible to maintain a non-drainage structure state so that it is sealed. Since the propulsion method can be realized, for example, even if the fault crush zone is broken during propulsion, water can be prevented from flowing into the pipe 3, and the collapse of the natural ground 5 can be prevented. The drainage structure can be achieved, and the ground 5 can be drained reliably.

Next, as an example of use of the pipe 3, a tunnel construction method using the pipe 3 will be described with reference to FIG. 3 and FIG.
As shown in FIG. 3, when the main tunnel 1 such as a road tunnel is constructed by a mountain tunnel method or the like in a natural ground such as a small earth covering or a fault crush zone, the natural ground 5 in front of the face 4 of the main tunnel 1 is used. The front of the tunnel 2 for the purpose of draining water using the propulsion method, and the ground in front of the face 4 of the main tunnel 1 under construction through the water draining pipe 3 installed in the tunnel 2 After lowering the groundwater level of No. 5, the excavation work of the main tunnel 1 under construction and the excavation work of the propulsion tunnel 2 are performed in parallel.
For example, before constructing the main tunnel 1, the propulsion tunnel 2 is formed in the ground 5 below the main tunnel 1, and the face 6 of the propulsion tunnel 2 precedes the face 4 of the main tunnel 1. Thereafter, the excavation work of the main tunnel 1 and the excavation work of the propulsion tunnel 2 are simultaneously performed.
Then, after the face 6 of the propulsion tunnel 2 is positioned forward by a certain distance H from the tip of the face 4 of the main tunnel 1 digging upward toward the ground 5 in front of the face 4, the main tunnel 1 The excavation work of the tunnel 1 and the excavation work of the propulsion tunnel 2 are simultaneously performed, and the distance between the face 4 of the main tunnel 1 and the face 6 of the propulsion tunnel 2 is maintained at a constant distance H.

The said fixed distance H shall be in the range of 2m-5m, for example. Usually, when excavation and construction of a mountain tunnel in a natural ground such as a small earth covering or a fault crushing zone, the ground from the tip of the face 4 of the tunnel 1 to a ground 5 in front of the face 4 is 2m to 5m ahead. The mountain range corresponds to the amount of excavation work for one to two days when excavating the natural ground 5 to form the main tunnel 1.
Accordingly, the excavation work for forming the main tunnel 1 and the excavation work for forming the propulsion tunnel 2 are performed while maintaining the distance between the face 4 of the main tunnel 1 and the face 6 of the propulsion tunnel 2 at 2 m to 5 m. If it is made to perform simultaneously, the natural ground part 5A in the range of 2m-5m ahead from the face 4 of the tunnel cavity part of this tunnel 1 will be excavated after being left for 1 to 2 days. The water of the natural mountain portion 5A within the range of 2m to 5m ahead from the face 4 of the main tunnel 1 left for 1 to 2 days was installed by the propulsion tunnel 2 in the natural mountain portion 5A. Water is drained by the tube 3.
Therefore, the natural ground portion 5A in the range of 2m to 5m ahead of the face 4 of the main tunnel 1 is drained by the pipe 3 during the first to second days before excavation, and the groundwater level is lowered moderately. In addition, since the groundwater level 5 is prevented from excessively lowering the groundwater level, it is possible to prevent the fall of the face 4 of the main tunnel 1 during construction, and the dry sand phenomenon of the face 4 of the main tunnel 1. Can be prevented.

Hereinafter, an example of the procedure of the tunnel construction method will be described with reference to FIG.
Using the pipe installation device 10 described above, the propulsion tunnel 2 in which the pipe 3 is installed by the propulsion method is constructed, for example, below the ground 5 to be excavated to form the tunnel cavity of the main tunnel 1, and the propulsion tunnel The 2 face 6 is set to 2 m to 5 m from the front end of the face 4 of the main tunnel 1 digging above the propulsion tunnel 2 (see FIG. 3A).
Next, it is carried out simultaneously with the excavation work of the main tunnel 1 and the excavation work of the propulsion tunnel 2, and the constant distance H between the face 4 of the main tunnel 1 and the face 6 of the propulsion tunnel 2 is maintained within a range of 2 m to 5 m. (See FIG. 3C). Thereby, since the water of the natural ground portion 5A in front of the face 4 excavated to form the main tunnel 1 is drained through the pipe 3 before excavation, the natural ground in front of the face 4 to be excavated. Portion 5A has a moderately low groundwater level and an excessively low groundwater level to prevent the ground 5 from having a moderate water content, so that it can prevent the face 4 of the main tunnel 1 from collapsing during construction. The dry sand phenomenon of the face 4 can be prevented.

In the excavation work of the propulsion tunnel 2, a jack 13 is installed at the rear end of the pipe 3, a pressure bearing body 14 is installed behind the jack 13, the jack 13 is extended to propel the pipe 3, and excavation means The pipe 3 may be pushed while excavating the natural ground 5 at 11. After the one-time propulsion operation of the pipe 3, the jack 13 was moved forward, the pressure bearing body 14 was installed, and the ground 5 at the front portion of the jack 13 was excavated by the amount that the pipe 3 was propelled. Later (see FIG. 3B), by repeating the above operation, one pipe is advanced, so that the pipe 3 is not left behind the propulsion tunnel 2. If the bearing body 14 is composed of the invert concrete 7 that has been placed, the installation work of the bearing body 14 can be simplified.
When the extension stroke of the jack 13 is insufficient, a pipe (dummy pipe) (not shown) may be interposed between the piston head 15 of the jack 13 and the rear end 16 of the pipe 3. For example, when it is desired to propel the pipe 3 by 5 m using the jack 13 having an extension stroke of 3 m, the pipe 3 is propelled by 3 m and then the piston head 15 that has been retracted and the rear end 16 of the pipe 3 have a length of 2 m or more. What is necessary is just to push the pipe | tube 3 by extending a piston by interposing length pipe | tube (dummy pipe | tube).
Further, the excavation work of the tunnel 1 may be performed by operating an excavating machine (not shown).
In FIG. 4, 7 is the inverted concrete of the main tunnel 1, 8 is the lining concrete of the main tunnel 1, and 9 is the support work of the main tunnel 1.

According to the tunnel construction method described above, the face 6 of the propulsion tunnel 2 that is installed by propelling the pipe 3 is located 2 m to 5 m from the tip of the face 4 of the main tunnel 1 that is being constructed to be excavated above the propulsion tunnel 2. The excavation of this tunnel 1 under construction is advanced 2m-5m, which corresponds to the amount of tunnel excavation work for one to two days. It is suitable for excavating the natural ground portion 5A because the groundwater level of the portion 5A is moderately lowered within the period of 1 to 2 days and excavated before the natural ground portion 5A is dried. Thus, it is possible to prevent the fall of the face 4 of the main tunnel 1 and to prevent the generation of dry sand at the face 4 of the main tunnel 1.
As described above, during the propulsion of the pipe 3, since the pipe 3 is propelled by the closed type propulsion method as a non-drainage structure, for example, water flows into the pipe 3 even when a fault crush zone exists during the propulsion. Such a situation can be prevented, and the pipe 3 can be reliably installed on the natural ground 5 by the propulsion method, and the drainage of the natural ground 5 can be reliably performed by setting the pipe 3 to the drainage structure state after the completion of the promotion.
Moreover, since the pipe 3 is installed by the propulsion method, the diameter of the pipe 3 can be increased (for example, 1 m or more), and the water collecting ability of the pipe 3 can be increased, so that a sufficient draining effect can be obtained. Further, since only one pipe 3 is promoted, the construction cost can be reduced. That is, it is possible to realize a water draining method in tunnel construction that has a high water collecting capacity and can reduce the construction cost.

  If the fixed distance H is determined according to the geology of the natural ground 5 and the excavation work of the main tunnel 1 and the excavation work of the propulsion tunnel 2 are performed simultaneously while maintaining the constant distance H, the tunnel 1 It can be a wet ground 5 suitable for excavating the natural ground 5 in front of the face 4, can prevent the face 4 of the tunnel 1 from collapsing, and can prevent the occurrence of dry sand in the face 4 of the tunnel 1. It becomes like this.

  3 pipes, 31 outer pipes, 32 inner pipes, 35 through holes, 36 filters.

Claims (1)

It is a pipe installed in the natural ground by the propulsion method,
An outer tube having a circular cross section with a plurality of through-holes penetrating inside and outside of the tube and an inner tube having a circular cross section are provided, and only the inner tube is connected with the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube in contact with each other. The outer diameter of the inner tube and the inner diameter of the outer tube are set so that the inner tube can be rotated about the center axis of the inner tube, and the inner tube is rotated about the center axis of the inner tube. A drainage structure in which the center of each through-hole of the inner tube and the center of each through-hole of the outer tube coincide with each other and the through-hole of the inner tube communicates with the through-hole of the outer tube; Set to a non-drainage structure where the outer peripheral surface side opening of the tube is closed by the inner peripheral surface of the outer tube and the inner peripheral surface side opening of each through hole of the outer tube is closed by the outer peripheral surface of the inner tube It is possible and has a configuration in which a filter that allows water to pass through without passing through the earth and sand is installed in each through hole of at least one of the inner pipe and the outer pipe, and is not used during propulsion. Water structural states can be realized sealed jacking method, a tube, which is a double pipe structure capable drainage structure state after promotion ends.

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