JP4859692B2 - Tunnel internal structure construction method - Google Patents

Description

  The present invention relates to a tunnel internal structure construction method.

  Conventionally, when building tunnels for railways, roads, etc. using earth pressure type shield machines, tunnels are made using hardener mixed soil in which hardener is added to excavated soil generated by shield excavation at the same time as shield excavation. There has been a method of forming an inner roadbed or putting excavated soil into the inside of a tunnel roadbed made of a precast member or the like (see, for example, Patent Document 1).

  Moreover, when constructing a tunnel using a muddy water shield machine, there has been a method and an apparatus for modifying excavated soil and using it for constructing a tunnel internal structure (see, for example, Patent Document 2 and Patent Document 3).

JP 60-226999 A Japanese Patent No. 2527289 Japanese Utility Model Publication No. 5-47097

  However, the portion of the tunnel interior that can be used as a work space during the construction of the tunnel is limited, and in order to shorten the construction period, it was necessary to efficiently use the tunnel interior.

The present invention has been made in view of such problems, and an object of the present invention is to provide a tunnel internal structure construction method that can secure a transport path to the face in the tunnel internal structure.

The first invention for achieving the above-described object is the step (a) of installing a culvert to be used as a transport path in the lower part of the tunnel while digging the tunnel, and tunnel excavation soil in the tunnel. A step (b) of reforming the fluidized soil into a fluidized soil, and a step (c) of backfilling the fluidized soil in the tunnel to a level covering the culvert , wherein the step (b) The tunnel excavated soil is modified into a plurality of fluidized soils having different strengths after curing, and in the step (c), a lower one of the plurality of fluidized soils having a lower strength after curing is used as a lower layer. In addition, the tunnel internal structure construction method is characterized in that a high-priced material is used for the upper layer and backfilled .

The second invention includes a step (a) of installing a culvert to be used as a conveying path while digging a tunnel, and reforming the tunnel excavated soil into fluidized treated soil in the tunnel. And (c) backfilling the fluidized soil into the tunnel to a level covering the culvert, the culvert comprising a lower half and an upper half And having a PC fixing box on the convex portion provided on the outer peripheral surface and the upper surface of the bottom plate, and in the step (a), the lower half and the upper half are integrated using a joint, and the lower half It is a tunnel internal structure construction method characterized in that the parts and the upper half parts are fastened together in the tunnel axis direction using a PC steel rod.

The third invention includes a step (a) of installing a culvert to be used as a conveying path while digging a tunnel, and modifying the tunnel excavated soil into fluidized soil in the tunnel. And (c) a step of backfilling the fluidized soil into the tunnel to a level covering the culvert. In the step (a), an angle material is formed on the tunnel segment. And the culvert is positioned by using the angle member.

The fourth invention includes a step (a) of installing a culvert to be used as a conveyance path while digging a tunnel in the lower part of the tunnel, and modifying the tunnel excavated soil into fluidized soil in the tunnel. And (c) backfilling the fluidized soil in the tunnel to a level covering the culvert, and in the step (a), the culvert is transported by a carriage. An outer frame portion that is disposed so as to straddle the conveyance carriage, and that is self-propelled on a segment; a temporary support base that is fixed in the outer frame portion; and A tunnel internal structure construction method characterized by being installed using a culvert assembling apparatus comprising a culvert holding section that moves up and down and rotates.

In the present invention, a step (d) of providing an unreinforced concrete base layer on the fluidized soil may be further provided. In the step (b), for example, the table flow value of the fluidized soil is set to 160 mm or more and 210 mm or less, and the breathing rate is set to 1% or less. In the step (a), an adjustment liner, a spacer, an injection material, and the like are installed between the bottom surface of the culvert and the tunnel segment as necessary.
The culvert assembling apparatus lifts the culvert transported to a predetermined position by the transport carriage and temporarily places it on the temporary support stand. After the transport carriage is moved, it is rotated and lowered by the culvert support section to the predetermined position. To install.

  In the present invention, a culvert for use as a conveyance path is installed in the lower part of the tunnel while digging the tunnel. In parallel with the tunnel excavation, the tunnel excavated soil is reformed into fluidized soil in the tunnel, and the fluidized soil is backfilled in the tunnel to a level covering the culvert.

  ADVANTAGE OF THE INVENTION According to this invention, the tunnel internal structure construction method which can ensure the conveyance path to a face in a tunnel internal structure can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view in the axial direction of a tunnel 3 whose internal structure is being constructed. In FIG. 1, the direction shown by the arrow A is the face side of the tunnel 3, and the direction shown by the arrow B is the shaft side. FIG. 2 is a diagram illustrating each process when the arch culvert 11 is installed using the culvert assembling apparatus 13. FIG. 3 is a diagram showing a state in which the culvert 11 is installed in the tunnel 3. 3 is a cross-sectional view taken along the line CC of FIG.

As shown in FIGS. 1 and 3, the tunnel 3 is excavated in the natural ground 1 using a shield machine (not shown). The segment 5 is transported inside the tunnel 3 by using a transport carriage 9a. The transported segment 5 is assembled along the inner wall of the tunnel 3. The excavated soil 8 of the tunnel 3 is conveyed backward in the excavation direction by using a belt conveyor 7 attached to the inner wall of the tunnel 3.

  Behind the excavation direction of the tunnel 3, the construction of the internal structure is started at an appropriate distance from the face. In order to construct the internal structure, as shown in FIGS. 1 to 3, the lower half part 11 a of the arch culvert and the upper half part 11 b of the arch culvert 11 b are transported to the culvert assembly part 18 using the transport carriage 9 b. The transport carriage 9b travels on the segment 5. The arch culvert lower half 11a and the arch culvert upper half 11b are precast members. The arch culvert lower half 11 a and the arch culvert upper half 11 b are transported simultaneously with the segment 5.

After conveying the lower half part 11a of the arch culvert and the upper half part 11b of the arch culvert to the culvert assembly part 18, the arch culvert 11 composed of the lower half part 11a of the arch culvert and the upper half part 11b of the arch culvert is used by using the culvert assembly device 13. Assemble.

As shown in FIGS. 1 and 2, the culvert assembling apparatus 13 includes an outer frame portion 12, a culvert holding portion 14, a temporary support base 16, traveling means 20, and the like. The outer frame portion 12 is, for example, a gate-shaped member having a predetermined length in the tunnel axis direction, and is disposed so as to straddle the transport carriage 9b.

The traveling means 20 includes a traveling means 20 a provided at the lower end portion of the both side surfaces 12 a of the outer frame portion 12, and a traveling means 20 b provided so as to protrude outward from the both side surfaces 12 a. The culvert assembling apparatus 13 self-travels on the segment 5 in the tunnel axis direction using the traveling means 20.

The culvert holding part 14 is a mechanism for holding the arch culvert lower half part 11 a and the arch culvert upper half part 11 b and is supported by the outer frame part 12. As shown by an arrow I in FIG. 1, the culvert holding unit 14 is movable in the culvert assembling apparatus 13 in the tunnel axis direction. Further, the culvert holding part 14 moves the held arch culvert lower half part 11a and the arch culvert upper half part 11b up and down as indicated by an arrow J in FIG.

The temporary support base 16 is a pair of plate-like members that are fixed substantially vertically to the side surface 12 a inside the both side surfaces 12 a of the outer frame portion 12. The temporary support stand 16 is provided at a predetermined position on the rear portion of the culvert assembling apparatus 13.

  FIG. 2A is a diagram illustrating a process of lifting the arch culvert 11b. When assembling the arch culvert 11, first, the arch culvert upper half 11 b (FIG. 1) placed on the transport carriage 9 b is held using the culvert holding portion 14. Then, the arch culvert upper half portion 11b is lifted using the culvert holding portion 14, rotated, moved in the shaft direction, and temporarily placed on the temporary support base 16 as shown in FIG. .

  FIG. 2B is a diagram showing a process of lifting the lower half portion 11a of the arch culvert. After temporarily placing the arch culvert upper half portion 11b on the temporary support base 16, the culvert holding portion 14 is moved onto the arch culvert lower half portion 11a (FIG. 1) placed on the transport carriage 9b. Next, the lower half portion 11a of the arch culvert 11a is held by using the culvert holding portion 14, and as shown in FIG. And the conveyance trolley 9 in which all unloading was completed is passed to the shaft side.

  FIG. 2C is a diagram illustrating a process of installing the arch culvert lower half 11 a on the segment 5. After passing the carriage 9 to the shaft side, the lower half portion 11a of the arch culvert is rotated using the culvert holding portion 14 and moved in the shaft direction, as shown in FIG. And installed on the segment 5.

  FIG. 4 is a sectional view of the arch culvert 11 in the circumferential direction. FIG. 4 is an enlarged view of a portion indicated by a range E in FIG. FIG. 5 is a perspective view of the arch culvert 11. FIG. 6 is a cross-sectional view around the angle member 37. FIG. 6 is an enlarged view of a portion indicated by a range F in FIG.

When installing the lower half part 11a of the arch culvert on the segment 5, an angle member 37 is fixed inside the segment 5 at the lower part of the tunnel 3 as shown in FIG. The angle member 37 is fixed to the planned installation positions of both outer corners 28 of the bottom plate 27 of the lower half portion 11a of the arch culvert.

As shown in FIG. 6, in the segment 5, a female screw 45 is embedded at the installation position of the angle member 37. The angle member 37 has a bolt hole 50. The angle member 37 is fixed to the segment 5 by screwing the bolt 47 inserted into the bolt hole 50 into the female screw 45 of the segment 5 and fastening with the bolt 47. A washer 49 is disposed between the angle member 37 and the segment 5.

After fixing the angle member 37 to the segment 5, positioning is performed by the angle member 37, and the arch culvert lower half part 11 a is installed on the segment 5 at the lower part of the tunnel 3. Then, an injection material 43 is injected between the bottom surface 41 of the bottom plate 27 of the lower half portion 11 a of the arch culvert and the segment 5.

In the tunnel 3, the vertical displacement may occur when the segment 5 is assembled. By injecting the injection material 43 between the bottom surface 41 of the lower half part 11 a of the arch culvert 11 and the segment 5, the lower half part of the arch culvert It is possible to prevent the vertical displacement of the portion 11a. Further, by using the angle member 37, it is possible to prevent the displacement of the arch culvert lower half 11a in the tunnel circumferential direction.

FIG. 2D is a diagram showing a process of installing the arch culvert upper half 11b on the arch culvert lower half 11a. After the arch culvert lower half part 11a is installed on the segment 5, the culvert holding part 14 is moved onto the arch culvert upper half part 11b (FIG. 2A) temporarily placed on the temporary support base 16. Next, the arch culvert upper half part 11b is held by using the culvert holding part 14 and moved in the shaft direction, and as shown in FIGS. 1 and 2 (d), on the arch culvert lower half part 11a. Install in. Then, as shown in FIGS. 4 and 5, the lower half part 11 a of the arch culvert and the upper half part 11 b of the arch culvert are integrated using a mortar filling type reinforcing bar joint 35.

As shown in FIG. 4, the culvert lower half 11 a has PC fixing boxes 25 a at two locations on the upper surface 29 of the bottom plate 27. As shown in FIG. 5, the arch culvert lower half portions 11a are fastened together in the axial direction of the tunnel 3 using a PC steel rod 31a. As shown in FIGS. 4 and 5, the PC steel rod 31a is fixed using a PC fixing box 25a.

As shown in FIG. 4, the arch culvert upper half portion 11 b has PC fixing boxes 25 b on convex portions 39 provided at two locations on the outer peripheral surface 33. As shown in FIG. 5, the arch culvert upper half portions 11b are fastened together in the axial direction of the tunnel 3 using a PC steel rod 31b. As shown in FIGS. 4 and 5, the PC steel bar 31b is fixed using a PC fixing box 25b.

  In the upper half portion 11b of the arch culvert, the workability at the time of fixing the PC steel rod 31b can be improved by providing the PC fixing box 25b on the convex portion 39 provided on the outer peripheral surface 33.

The interior 23 of the arch culvert 11 is used as a transport path for transporting materials and equipment for constructing the tunnel 3 between the shaft side and the face side. It is also used as a pipe space.

  FIG. 7 is a view showing a state in which the lower layer fluidized soil 17 is backfilled in the tunnel 3. FIG. 7 is a cross-sectional view taken along arrow DD in FIG. FIG. 8 shows a cross-sectional view in the axial direction of the tunnel 3 during construction of the internal structure. FIG. 8 is a diagram illustrating a continuation of the direction indicated by the arrow B in FIG. 1 (backward in the excavation direction). In FIG. 8, the direction shown by the arrow G is the face side of the tunnel 3, and the direction shown by the arrow H is the shaft side.

  As shown in FIG. 8, the excavated soil 8 produced by excavating the tunnel 3 is transported by the belt conveyor 7 to the fluidized treated soil creation location 61 behind the tunnel 3 in the excavating direction. In the fluidized soil creation site 61, a fluidized soil creation device 59 including a concrete pump, a mobile batcher plant, a self-propelled soil improvement machine, and the like is installed.

The excavated soil 8 transported to the fluidized soil creation site 61 is hydrated by a fluidized soil creation device 59, added with a solidifying material such as cement, mixed, and converted into a muddy fluidized soil. Quality. In the present embodiment, the excavated soil 8 is modified into two types of fluidized soils having different strengths after hardening. At this time, it is desirable to set the table flow value of each fluidized soil to 160 mm to 210 mm and the breathing rate to 1% or less.

  After creating the fluidized soil at the fluidized soil creation location 61, the fluidized soil is transported forward in the excavation direction of the tunnel 3. And it casts in the fluidization processing soil placement location 19 located in the back of the excavation direction of the culvert assembly location 18, and the fluidization processing soil layer 63 (FIG. 8) is formed. The movable mold 15 is disposed at the end of the fluidized soil placement site 19 on the face side.

In order to form the fluidized soil layer 63, first, as shown in FIG. 1 and FIG. 7, the lower layer fluidized soil 17 having a low strength after curing is used. The lower part of the inner space 21 of 3 is refilled. For example, the lower layer fluidized soil 17 is backfilled to a level at which a part of the upper half of the arch culvert 11b is hidden. At this time, unequal settlement may be suppressed by expanding a high strength plastic net that has been folded in advance and placing it in the lower layer fluidized soil 17.

FIG. 9 is a view showing a state in which an unreinforced concrete base layer 55 is provided in the tunnel 3. FIG. 9 is a cross-sectional view taken along arrows II shown in FIG. After the lower part of the inner space 21 of the tunnel 3 is backfilled by the lower layer fluidized soil 17, as shown in FIGS. 8 and 9, the upper layer fluidized processing having a high strength after curing of the two types of fluidized soil. Using the soil 53, the upper part of the lower layer fluidized soil 17 in the inner space 21 of the tunnel 3 is refilled. The upper layer fluidized soil 53 is backfilled to a level covering the arch culvert 11.

The convex portion 39 provided on the outer peripheral surface 33 of the arch culvert 11 increases the resistance between the surface of the arch culvert 11 and the fluidized soil layer 63. The fluidization treatment soil placement site 19 is opened to the construction vehicle after the construction of the upper layer fluidization treatment soil 53.

In the unreinforced concrete placement location 57 located behind the fluidization treatment soil placement location 19 in the excavation direction, unreinforced concrete is placed on the upper surface of the fluidization treatment soil 53 in the upper layer of the fluidization treatment soil layer 63, A concrete base layer 55 is formed. The unreinforced concrete base layer 55 disperses the loading load and reduces uneven settlement of the upper portion of the arch culvert 11 and the backfill portion of the side portion. After placing the unreinforced concrete base layer 55, paving or the like is performed to complete the internal structure 63.

Thus, according to the present embodiment, the transport cart 9 is used to simultaneously transport the segment 5, the lower half portion 11a of the arch culvert, and the upper half portion 11b of the arch culvert, and in parallel with the excavation of the tunnel 3, By assembling 11, the construction period is shortened. Further, in parallel with the excavation of the tunnel 3, the excavated soil 8 is reformed to the fluidized treated soil, and the fluidized treated soil is backfilled to a level covering the arch culvert 11, thereby reducing the processing cost associated with the diversion of the excavated soil 8. Reduction is possible. Furthermore, by effectively using the excavated soil 8, it is possible to reduce the load on the surrounding environment and the amount carried out by dumping.

In addition, by installing the arch culvert 11 in the lower part of the tunnel 3 and then backfilling the fluidized soil, the transport path to the face can be secured before the fluidized soil is backfilled, and short-term construction is possible. .

In FIG. 3, the injection material 43 is injected between the bottom surface 41 of the lower half portion 11 a of the arch culvert 11 and the segment 5 of the tunnel 3, but an adjustment liner, a spacer, or the like may be installed instead of the injection material 43. . Even when an adjustment liner, a spacer, or the like is used, it is possible to prevent the vertical displacement of the lower half portion 11a of the arch culvert 11a due to the assembly error of the segment 5, and to install the arch culvert 11 at a predetermined position.

Further, in the present embodiment, the excavated soil 8 is modified into two types of fluidized soil, but may be modified to one type of fluidized soil and backfilled to a level covering the arch culvert 11. Further, it may be modified to three or more types of fluidized soil and backfilled to a level covering the arch culvert 11 by using a low-strength after hardening in the lower layer and a higher one in the upper layer. The position of the fluidized soil creation place is not limited to that shown in FIG.

  As mentioned above, although preferred embodiment of the tunnel internal structure construction method concerning this invention was described referring an accompanying drawing, this invention is not limited to this example. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

A sectional view in the axial direction of the tunnel 3 which is building the internal structure The figure which shows each process at the time of installing the arch culvert 11 using the culvert assembly apparatus 13 The figure which shows the state which installed the culvert 11 in the tunnel 3 Cross section in the circumferential direction of the arch culvert 11 Perspective view of arch culvert 11 Sectional view around the angle member 37 The figure which shows the state which filled back the lower layer fluidization processing soil 17 in the tunnel 3 A sectional view in the axial direction of the tunnel 3 which is building the internal structure The figure which shows the state which laid the unreinforced concrete 55 in the tunnel 3

Explanation of symbols

1 ......... Takeyama 3 ......... Tunnel 5 ......... Segment 11 ......... Arch culvert 11a ......... Lower half of arch culvert 11b ......... Upper half of arch culvert 12 ......... Outer frame 13 ... ... Calvert assembly device 14 ......... Calvert holding part 16 ......... Temporary stand 17 ......... Lower layer fluidized soil 25a, 25b ......... PC fixing box 27 ......... Bottom plate 29 ......... Upper surface 31a, 31b ... ...... PC steel rod 33 ......... Outer peripheral surface 35 ......... Mortar-filled steel bar joint 37 ......... Angle material 39 ......... Protrusions 41 ......... Bottom surface 43 ......... Injection material 53 ......... Upper layer fluidization Treated soil 55 ………… Unreinforced concrete base layer 63 ………… Fluidized treated soil layer 65 ……… Internal structure

Claims (7)

A step (a) of installing a culvert for use as a transport path in the lower part of the tunnel while digging the tunnel;
(B) modifying the tunnel excavated soil into fluidized soil within the tunnel;
Backfilling the fluidized soil into the tunnel to a level covering the culvert (c);
Equipped with,
In the step (b), the tunnel excavated soil is modified into a plurality of fluidized soils having different strengths after hardening,
In the step (c), among the plurality of fluidized soils, a method of constructing a tunnel internal structure is provided by using a lower strength after curing and a higher one as a top layer to backfill . A step (a) of installing a culvert for use as a transport path in the lower part of the tunnel while digging the tunnel;
  (B) modifying the tunnel excavated soil into fluidized soil within the tunnel;
  Backfilling the fluidized soil into the tunnel to a level covering the culvert (c);
Comprising
  The culvert has a lower half part and an upper half part, and has a PC fixing box on the convex part provided on the outer peripheral surface and the upper surface of the bottom plate,
  In the step (a), the lower half and the upper half are integrated using a joint, and the lower halves and the upper halves are fastened together in the tunnel axis direction using a PC steel rod. The tunnel internal structure construction method characterized by this. A step (a) of installing a culvert for use as a transport path in the lower part of the tunnel while digging the tunnel;
  (B) modifying the tunnel excavated soil into fluidized soil within the tunnel;
  Backfilling the fluidized soil into the tunnel to a level covering the culvert (c);
Comprising
In the step (a), an angle member is fixed to a segment of the tunnel, and the culvert is positioned using the angle member, and the tunnel internal structure construction method is characterized. A step (a) of installing a culvert for use as a transport path in the lower part of the tunnel while digging the tunnel;
  (B) modifying the tunnel excavated soil into fluidized soil within the tunnel;
  Backfilling the fluidized soil into the tunnel to a level covering the culvert (c);
Comprising
  In the step (a), the culvert is transported using a transport carriage,
  An outer frame portion that is arranged so as to straddle the transport carriage, and that runs on the segment,
  A temporary cradle fixed in the outer frame part;
  A culvert holding part provided on the outer frame part for vertically moving and rotating the culvert;
A tunnel internal structure construction method characterized by being installed using a culvert assembling apparatus. The tunnel internal structure construction method according to any one of claims 1 to 4, further comprising a step (d) of providing an unreinforced concrete base layer on the fluidized soil. The said process (b) WHEREIN: The table flow value of the said fluidization processing soil is set to 160 mm or more and 210 mm or less, and a breathing rate is set to 1% or less, The Claim 1 characterized by the above-mentioned. Tunnel internal structure construction method. In the step (a), the between the segments of the bottom surface and the tunnel of the culvert, adjusting liner, a spacer, placing the injection material or the like from claim 1, wherein according to claim 6 Tunnel internal structure construction method.

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