JP2006307478A - Arch support construction method and apparatus for widening tunnel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device for constructing an arch support for increasing the width of a tunnel capable of continuously, efficiently, and economically constructing the arch support extended from the outer periphery of the tunnel without occupying a ground site and simultaneously on the rear side even during the construction of the tunnel and further capable of not only securely stabilizing earth and maintaining the level of underwater but also stably securing a heading without loosening the earth during the construction. <P>SOLUTION: An arch type tunnel boring machine 3 is started from a start lateral 1 excavated starting at the tunnel is advanced, and while slitting the earth in an arch shape by propelling the arch type boring machine by a propelling jack 3 through segments 5 assembled in an arch shape, the segments are sequentially pushed into the arch slit 4 to construct the arch support C1 formed of the segments. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method and apparatus for constructing an arch support for widening a tunnel.

  For example, at the junction of road tunnels, it is necessary to cut and expand two tunnels to build a pillar-free space. Auxiliary construction method is required.

  Conventionally, as one of them, there is ground improvement by chemical solution injection or freezing method, but a wide range of improvement is necessary, and the cost is high and the construction period is long.

  Moreover, there is a curved pipe roof construction method as shown in FIGS. In this construction method, one of the two existing tunnels 51 and 52 is excavated from one side to the other, curved pipes 53 are inserted one by one, and ground improvement 54 is applied between adjacent curved pipes 53 by a freezing method or the like. Water.

  However, according to this, since excavation and pipe insertion are performed one by one, it takes time. In addition, since the curved pipe 53 is not continuous in the tunnel axis direction, it is necessary to provide a ground improvement 54 between the adjacent curved pipes 53, which increases the cost and the construction period.

  Patent Document 1 (Japanese Patent No. 3096665) discloses the following method of constructing a widened portion that becomes an emergency parking zone between two parallel shield tunnels for roads.

  The top and bottom ground improvement parts are formed by improving the ground above and below the ground between the two shield tunnels. The arched girder is propelled and pressed into the upper ground improvement part from one shield tunnel and penetrated into the other shield tunnel, and this process is repeated to connect the arched girder in the required section. It is assumed to be a mountain dome. After that, in each shield tunnel, the segment located between the arched girder and the lower ground improvement part was removed to form an opening, and the ground between the two shield tunnels was excavated from this opening. Communicate between the inner sections of the shield tunnel. Then, the lower ground improvement portion is excavated by a predetermined depth, and concrete is placed therein to form a bottom plate.

  However, in this case as well, it is necessary to improve the ground between the two shield tunnels, and to push the arch-shaped beam material into the ground improved portion, which is similar to the curved pipe roof construction method shown in FIGS. Is high and the construction period is long.

Furthermore, there is a method of constructing an arch-shaped support between underground walls or tunnels as a receiving work for large-section underground cavities and tunnels, but the structure is constructed by assembling segments within the excavator. The lining thickness of the work becomes thick, and it is difficult to reduce it to about 1 m or less. In addition, a shaft from the ground is required for carrying in, starting, and reaching the excavator, which requires a lot of construction cost and construction period.
Japanese Patent No. 3096665

  The problem of the present invention is that an arch-shaped support projecting from the outer periphery of the tunnel can be constructed efficiently and economically continuously without occupying the land for ground use, and can be constructed simultaneously at the rear even during tunnel construction. An object of the present invention is to provide an arch support construction method and apparatus for widening a tunnel, which can not only stably stabilize the mountain and maintain the groundwater level, but also ensure the stability of the face without loosening the ground.

<Invention according to Claim 1>
The method according to the invention comprises excavating a starting side pit from a tunnel, starting an arched excavator from the starting side pit, and propelling the arched excavator with a propulsion jack through segments that are assembled into an arch. While excavating the natural mountain into an arch shape, the segments are sequentially pushed into the arch shape slit to construct an arch-shaped support by the segment.

As a preferred specific embodiment, there is the following method.
<Invention according to Claim 2>
While assembling the segments into the arch in the tunnel, they are fed into the starting side shaft and propelled by a propulsion jack and pushed into the slit from the starting side shaft.

<Invention according to claim 3>
Piping for arched excavator drilling is performed through the hollow part of the segment.
<Invention according to claim 4>
The arch excavator is dug to the arrival side shaft, dismantled in the arrival side shaft, and collected in the tunnel.

<Invention according to claim 5>
A slit is excavated between the first tunnel and the second tunnel which are parallel to each other, and an arch-shaped support with a segment is constructed between the tunnels and joined to both tunnels.

<Invention according to claim 6>
Slit excavation is performed in each of the upper and lower sides between the first tunnel and the second tunnel, and a symmetrical arch-shaped support is constructed between these tunnels.

<Invention according to claim 7>
The construction of the arch-type support work while digging up the arch-type excavator is performed along the support work advance guide provided on the outer peripheral surface of the existing tunnel.

<Invention according to claim 8>
The apparatus according to the present invention includes an arch excavator for slit excavation of natural ground and an arch-shaped segment propelled from the start side shaft, thereby sequentially pushing the segment into the arch-shaped slit, A propulsion jack that propels the excavator through the segment, and a piping system that is piped between the arch excavator and the starting horizontal shaft through the hollow portion of the segment in order to excavate the arch excavator It is characterized by.

<Invention according to claim 9>
The apparatus may further include a segment assembly feeding mechanism that feeds the inside of the tunnel into the starting side shaft while assembling the segments into an arch shape.

The present invention has the following effects.
(1) The arch excavator, which has started the arch excavator from the starting horizontal pit, is propelled by a propulsion jack through the segment assembled into an arch shape, and the ground is arched while slit excavating into the arch shape. Since it is sequentially pushed into the slit, the arch support for widening projecting from the outer periphery of the tunnel can be constructed continuously and efficiently without occupying the land for the ground, and the construction period can be shortened and the construction cost can be greatly reduced. it can.
(2) Since the lining is a continuous arch support for widening, it is possible to reliably stabilize the ground and maintain the groundwater level.
(3) Even during tunnel construction, it can be constructed simultaneously at the rear.
(4) Since the slit cutting can be performed while circulating the muddy water, the earth and sand can be discharged efficiently while ensuring the stability of the face without loosening the ground.
(5) Since the auxiliary construction method for water stop is minimized, it is not necessary to use an expensive construction method such as a freezing construction method.
(6) Even if it is thin, it is possible to construct an advance support structure for widening an arch-shaped cross section that is advantageous in strength.
(7) By constructing the upper and lower widening support bearings, it is possible to construct a succeeding tunnel parallel to the existing tunnel along the upper and lower widening support supports and widening between the two tunnels. Construction can be done safely.

(8) As in the invention according to claim 2, when the segments are fed into the starting horizontal shaft while being assembled in an arch shape in the tunnel, propelled by a propulsion jack and pushed into the slit from the starting horizontal shaft, Work up to construction can be done efficiently.
(9) If the piping for excavating the arch-shaped excavator is performed through the hollow portion of the segment as in the invention according to claim 3, the support construction while the arch-shaped excavator is excavated can be efficiently performed.
(10) As in the invention according to claim 4, when the arch-shaped excavator is dug up to the arrival side pit, disassembled in the arrival side pit and collected in the tunnel, It is possible to respond immediately to the next support construction.
(11) As in the invention according to claim 5, slit excavation is performed between the first tunnel and the second tunnel that are parallel to each other, and an arch-shaped support by a segment is constructed between these tunnels. When joined, a high-strength arch-shaped support can be constructed between two parallel tunnels.
(12) As in the invention according to claim 6, when excavating slits in the upper and lower portions between the first tunnel and the second tunnel, and constructing a vertically symmetrical arch-shaped support between these tunnels, 2 A large cross-section space surrounded by arch-shaped supporters can be constructed between two tunnels.
(13) As in the invention according to claim 7, when the construction of the arch-shaped support work while excavating the arch-shaped excavator is performed along the support work advance guide provided on the outer peripheral surface of the existing tunnel, The construction can be done in an orderly manner along the existing tunnel and can be easily joined to the existing tunnel.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  In this embodiment, when the main shield tunnel and the branch shield tunnel are in parallel, the main shield tunnel side to the branch shield tunnel side is an example in which an arched support is constructed between them. Figure 3 shows the overall construction image.

  As shown in these drawings, an arch-shaped upper side shaft 1 is excavated from the main shield tunnel A to the branch shield tunnel B, and several propulsion jacks 2 are juxtaposed to the side shaft 1 The arch-shaped excavator 3 is driven to start the arch-shaped excavator 3 from the starting horizontal shaft 1.

  After starting, the segment 5 is assembled into the arch shape in the main shield tunnel A and sent into the start side shaft 1, and the arch excavator 3 is propelled by the propulsion jack 2 through the segment 5 assembled in the arch shape. Drilling.

  As a result, the natural mountain is slit excavated into an arch shape by the arch-shaped excavator 3, and the segment 5 of one unit (hereinafter referred to as "one arch unit") assembled into the arch-shaped slit 4 is pushed into the arch-shaped slit 4. Is done. Then, when the arch-shaped excavator 3 is dug while repeating the pushing of the segments for each arch unit and the connection between the units, the arch-shaped upper support C1 by the segment 5 is constructed as shown in the figure. Is done.

The operation is a repetition of the following procedures (a), (b), and (c).
(A) Digging (muddy water circulation of excavation part, cutter drive while maintaining face water pressure, propulsion jack extension, soil removal by mud circulation)
(B) End of excavation when the segment length is exceeded (promotion jack shortened)
(C) Segment assembly (replacement of piping and wiring systems)

  Various piping / wiring systems 6 from the main shield tunnel A to the arched excavator 3 pass through the hollow portion 7 formed in the segment 5, and are piped / wired through the starting horizontal shaft 1.

  When the arch-shaped excavator 3 arrives at the reaching horizontal shaft 8 excavated from the main shield tunnel A, the arch-shaped excavator 3 is dismantled from the reaching horizontal shaft 8 in the reaching horizontal shaft 8 and inside the main shield tunnel A. To collect. When constructing the lower support C2 that is symmetrical with the upper support C1, the arch excavator 3 once disassembled and collected in the main shield tunnel A is reassembled in the lower starting horizontal shaft 9, Starting from the starting horizontal shaft 9 is started in the opposite direction, and the construction is performed in the same manner as described above until reaching the lower reaching horizontal shaft 10.

  4 to 6 illustrate segments used in the present embodiment. Assembling the segments into an arch shape and staggering them alternately in anticipation of the effect of joining the arch units, there are five types of segments 5A of type A, type B1, type B2, type C1, type C2. 5B1, 5B2, 5C2, and 5C2 are used. These five types of segments are all made of steel and have a ribbed structure that can withstand strength and compressive force during propulsion. The B1 type segment 5B1 has no hollow portion, but the other segments 5A, 5B2, 5C2, and 5C2 have a hollow portion 7. The piping / wiring system 6 passes through the hollow portion 7 at one end of the segment of one arch unit.

  The four types of segments 5B1, 5B2, 5C2, and 5C2 other than the A type include the lining segment of the main shield tunnel A and the covering of the branch shield tunnel B at both ends of one arch unit. In order to join the work segment as described later, the end faces of these four types of segments 5B1, 5B2, 5C2, and 5C2 are arcuate surfaces along the arc of the outer peripheral surface of the shield tunnel lining segment.

  7 and 8 show a cross-sectional structure of an A-type segment 5A as an example. The segment 5A is provided with a fastening bolt hole 11, an inter-piece water stop seal groove 12, and an inter-piece water stop seal 13.

  9 to 17 show the structure of the arch excavator 3. The excavator main body 14 of the arch-shaped excavator 3 can be assembled, disassembled, and recovered. In particular, the excavator main body 14 is disassembled once in the reaching side shaft 8 and recovered in the main shield tunnel A, and again in the starting side shaft 9. It is a structure that can be assembled. On the front surface of the excavator body 14, two upper and lower cutter bit groups 15a and 15b are mounted. Further, the upper and lower cutter bit groups 15a and 15b are separately driven by a cutter jack 16 that drives the upper and lower sides separately behind the bulkhead, a direction control jack 17 that performs direction control, a control device / measurement device wiring system 18, a cutter jack hydraulic piping 19, The direction control jack hydraulic pipe 20, the hydraulic return pipe 21, the muddy water feeding mud pipe 22, the muddy water discharge mud pipe 23 and the like are installed in the excavator main body 14. These pipes 19 to 23 are connected to the excavator drive control equipment in the main shield tunnel A, and the arch excavator 3 is excavated while being controlled in the left and right and up and down directions by remote operation from the main shield tunnel A. be able to.

  The cutter bit groups 15a and 15b are reciprocated left and right along the guide groove 25 by the cutter jack 16 and the cutter guide shaft 26 is slid along the slide guide 27 along with the cutter bit shaft 15a and 15b. Swing left and right at once to excavate natural ground. By simultaneously swinging the upper and lower two-stage cutter bit groups 15a and 15b in opposite directions, the excavation reaction force can be canceled out and the arch excavator 3 can be less shaken by excavation. In addition, between the cutter bit group 15a * 15b and the cutter jack 16, in the bulkhead part which forms a muddy water chamber, the water stop apparatus by packing etc. which resists sliding is provided.

  Further, as shown in FIG. 10, the excavator body 14 is provided with a mud inlet 28 at the center, a mud outlet 29 at the left and right ends, and a water pressure gauge 30 at the center.

  FIG. 18 shows a segment assembly feeding mechanism 31 that feeds the segments 5A, 5B1, 5B2, 5C2, and 5C2 into the starting horizontal shaft 1 while assembling them in the main line shield tunnel A. The segment assembling and feeding mechanism 31 includes a segment feeding guide rail 32 that extends in an arc shape from the main shield tunnel A into the starting horizontal shaft 1, a segment lifting device 33, and a segment feeding device 34. The segment feeding device 34 feeds the segment 5 lifted by the lifting device 33 into the starting horizontal shaft 1 along the segment feeding guide rail 32.

  FIG. 19 is a cross-sectional view taken along the line VII-VII in FIG. 18. The arch excavator 3 is propelled by propelling the segment 5 of one arch unit assembled in an arch shape with the propulsion jack 2. Indicates that FIG. 20 is a cross-sectional view of the same position, but shows a state in which there is still no segment 5 in the starting horizontal shaft 1 and the arch excavator 3 is directly propelled by the propulsion jack 2 and started.

  FIG. 21 shows a junction between the segment 5 of one arch unit and an existing tunnel (including the main shield tunnel A and the branch shield tunnel B). On the side of the existing tunnel segment 35, a recess 36 is formed in advance on the outer peripheral surface to be joined with the segment 5 of one arch unit, and in this recess 36, a filling material (for example, urethane foam or polystyrene foam) 37 that can be cut. To maintain the segment outer diameter. And using this recessed part 36 as a support excavation guide, an arch support is constructed while excavating the arch excavator 3 as described above.

  Further, as shown in FIG. 22, the end face of the segment 6 of one arch unit is applied to the recess 36, and the segment 5 of the one arch unit and the existing tunnel segment 35 are fastened and joined with a bolt 38. At this time, the recess 36 enhances the bonding property. In addition, it may join by other methods, such as welding joining and penetration joining other than joining by a bolt.

1 is an overall perspective view of an embodiment of the present invention. It is a top view of the part. It is sectional drawing of a tunnel cross-section direction. It is a perspective view of the assembly state of a segment. It is the front view for the 1 arch unit. FIG. 5 is a front view of one arch unit forming a zigzag group. FIGS. 5 and 6 show an A-shaped segment, in which (A) is a horizontal sectional view and (B) is an end view. (A) is a vertical sectional view in the length direction of the segment, and (B) is a vertical sectional view in the width direction. It is sectional drawing along the circular arc centerline of the longitudinal direction of an arched excavator. It is sectional drawing of the II position of FIG. It is a front view of an arched excavator. It is sectional drawing of the II-II position of FIG. It is sectional drawing of the III-III position of FIG. It is sectional drawing of the IV-IV position of FIG. It is a rear view of a part of an arcuate excavator. It is sectional drawing in the VV position in FIG. 9 of the part. It is a sectional view in the same VI-VI position. It is a front view of a segment assembly feeding mechanism. FIG. 18 is a cross-sectional view of the VII-VII position in FIG. 18, showing that the assembled segment is propelled by a propulsion jack, and the arch excavator is propelled through the propulsion jack. The cross-sectional view at the same position shows the state at the start of the arch excavator. It is sectional drawing which shows a junction part with the segment of 1 arch unit in the existing tunnel. It is sectional drawing which shows the joining state in this part. It is a perspective view of the curved pipe roof construction method which is a prior art example. It is sectional drawing of a XX position same as the above.

Explanation of symbols

A Main line shield tunnel B Branch shield tunnel C1 Upper support C2 Lower support 1 Start side shaft 2 Propulsion jack 3 Arch-type excavator 4 Arch-type slit 5, 5A, 5B1, 5B2, 5C2, 5C2 Segment 6 Piping and wiring system 7 Hollow part 8 Reaching horizontal shaft 9 Starting horizontal shaft 10 Reaching horizontal shaft 11 Fastening bolt hole 12 Inter-piece water stop seal groove 13 Inter-piece water stop seal 14 Excavator main bodies 15a and 15b Upper and lower cutter bits 16 Cutter jack 17 Direction control Jack 18 Control equipment / Measurement equipment wiring system 19 Cutter jack hydraulic pipe 20 Direction control jack hydraulic pipe 21 Hydraulic return pipe 22 Mud feed mud pipe 23 Mud drain mud pipe 24 Cutter drive shaft 25 Guide groove 26 Cutter guide shaft 27 Slide guide 28 Feed Mud mouth 29 Mud outlet 30 Water pressure gauge 31 Segment assembly feeding mechanism 32 Seg Cement fried guide rails 33 segment infeed heavy apparatus 34 segments infeed device 35 existing tunnel segment 36 recess 37 cuttable filler material 38 volts

Claims (9)

  An arch-shaped excavator is started from the starting horizontal pit excavated from the tunnel, and this arch-shaped excavator is propelled by a propulsion jack through the segment assembled into the arch shape to slit the natural mountain into an arch shape, A method for constructing an arch support for widening a tunnel, wherein the arch-shaped support is constructed by inserting segments into the arch-shaped slit sequentially.   2. The arch support construction method according to claim 1, wherein the segments are fed into the starting horizontal shaft while being assembled in an arch shape in the tunnel, and are pushed into the slit from the starting horizontal shaft by being propelled by a propulsion jack.   The arch support construction method according to claim 1 or 2, wherein piping for digging the arch excavator is performed through a hollow portion of the segment.   The arch support construction method according to claim 1, 2 or 3, wherein the arch excavator is dug up to the arrival side shaft, disassembled in the arrival side shaft and collected in the tunnel.   A slit excavation is made between the first tunnel and the second tunnel that are parallel to each other, an arch-shaped support by a segment is constructed between the tunnels, and the two tunnels are joined to each other. The arch support construction method according to 3 or 4.   6. The arch support construction according to claim 5, wherein slit excavation is performed in each of the upper and lower sides between the first tunnel and the second tunnel, and an arch-shaped support work having a vertical symmetry is constructed between the tunnels. Method.   The construction of an arch-shaped support while digging an arch-shaped excavator is performed along a support digging guide provided on the outer peripheral surface of an existing tunnel. Or the arch support construction method of 6.   The arch excavator for excavating natural ground into an arch shape, and the arch-shaped excavator segmented into the arch-shaped slit while pushing the segments sequentially into the arch-shaped slit by propelling the arch-shaped segment from the starting horizontal shaft Characterized in that it consists of a propulsion jack propelled through and a piping system piped between the arched excavator and the starting horizontal shaft through the hollow portion of the segment in order to dig up the arched excavator, Arch support construction equipment for tunnel widening.   9. The arch support construction apparatus according to claim 8, further comprising a segment assembly feeding mechanism that feeds the inside of the tunnel into the starting horizontal shaft while assembling the segments into an arch shape.

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