JP6374051B1 - How to build a tunnel - Google Patents

Abstract

The present invention provides a tunnel construction method capable of avoiding manual work at the face of a tunnel and improving safety and workability.
A method for constructing a tunnel includes a step of connecting a steel supporter to each other at the top ends by driving a pair of steel supporters while gripping each of the pair of hands, and driving the hands. By doing so, it has the process of arrange | positioning an arch-shaped steel support in an erection position. The top end of the pair of steel supports is provided with a first top end joint plate and a second top end joint plate. The first top end joint plate is provided with a female connection portion and is recessed. The male coupling | bond part is protrudingly provided by the 2 top end joint board. The male connecting portion has a rod-shaped male locking member protruding from the second top end joint plate, and the female connecting portion includes an opening hole formed through the first top end joint plate, and an opening hole. And a casing having therein a storage chamber in which an insertion port into which a male locking member can be inserted is formed. The male locking member inserted into the storage chamber from the insertion port is locked.
[Selection] Figure 1

Description

  The present invention relates to a tunnel construction method.

As a construction method for constructing a tunnel, a NATM construction method (New Austrian Tunneling Method) is known. The NATM method is based on the idea of maintaining the stability of the tunnel by making effective use of the support capacity and strength of the natural ground, using spray concrete, rock bolts, and steel support as appropriate. This is a method for constructing an integrated tunnel structure.

  When a tunnel is constructed in the NATM construction method, when an arch-shaped steel support is installed, it is usually performed according to the procedure described below. First, a spraying machine is set in the vicinity of the face, the concrete is first sprayed on the face, and when this is completed, the sprayer is withdrawn. Next, a work vehicle equipped with an erector for installing a support work in the vicinity of the face is arranged, and an arch-shaped steel support work is built in the tunnel pit wall near the face by the erector, and when this is completed, the work vehicle is withdrawn. Next, the sprayer is placed again on the face, and the tunnel supporter built is embedded, and then the concrete is secondarily sprayed, and the sprayer is moved out.

  When installing steel supporters, hold the left and right steel supporters at the tip of the boom of heavy machinery such as an erector and drill jumbo, and then perform the installation work. A general method is to build in an arch shape by connecting the joint plates provided at the ends to each other and bolting them.

Japanese Patent No. 3381606

  However, according to the conventional connection structure of steel supports, the work scaffolds and heavy equipment booms built near the tunnel pit wall with the joint plates provided on the left and right steel supports being in contact with each other Personnel are placed in the man cage, etc. installed in the machine, and the personnel are moved to the vicinity of the top of the tunnel.The bolts are inserted between the steel support joints located near the top of the tunnel, and the bolts are inserted with It was necessary to perform a connecting operation such as fastening.

  The present invention has been made in view of the above-described problems, and its object is to provide a tunnel construction method capable of avoiding manual work at the face of the tunnel and improving safety and workability. It is to provide.

The tunnel construction method according to the present invention includes an erector arrangement step in which a heavy machine including an erector apparatus having a pair of hands capable of gripping a pair of steel support members divided into arcs is arranged on the face of the tunnel, and A supporting work connecting step of connecting the pair of steel supporting works to each other at the top ends by driving the hand while holding the pair of steel supporting works on each of the pair of hands, A pair of steel support works, comprising: driving a hand to place an arch-shaped steel support work in which the top ends are connected to each other at a predetermined build-up position. Are connected to each other when the pair of steel supporters are connected to each other. First top end joint plate and second top end joint plate And a female coupling portion recessed in the first top joint plate, and a male coupling portion projecting from the second top joint plate, wherein the male coupling portion is 2 having a rod-shaped male locking member projecting from the top end joint plate, wherein the female connecting portion communicates with the opening hole formed through the first top end joint plate and the opening hole. A casing having therein a storage chamber in which an insertion port into which the male locking member can be inserted is formed, and the male locking member inserted into the storage chamber from the insertion port is locked.

  ADVANTAGE OF THE INVENTION According to this invention, the construction method of the tunnel which can avoid the manual work in the face of a tunnel and can improve safety | security and workability | operativity can be provided.

  Further, in the present invention, the female connecting portion is formed in the storage chamber and has a tapered hole having a tapered surface whose front diameter is reduced, and is divided into a plurality of portions in the circumferential direction in the tapered hole and the tapered surface. A wedge-shaped female locking member that is slidably disposed along the inner surface of the female locking member, a plurality of circumferential female locking grooves arranged on the inner surface of the female locking member, and the female locking member. A pressing member that presses forward, and the male connecting portion further includes a plurality of circumferential male locking grooves arranged in parallel on the outer periphery of the male locking member, and the male locking When the member is inserted from the insertion port of the female connecting portion, the male locking member moves back along the tapered surface against the pressing force of the pressing member. The male locking member is inserted into the storage chamber while expanding the inner surface of the female locking member. When the insertion of the male locking member into the storage chamber is completed, the female locking member is pushed back along the tapered surface by the pressing force of the pressing member. The male connecting portion and the female connecting portion may be integrally connected by reducing the inner diameter of the member and engaging the female locking groove and the male locking groove with each other.

  In the present invention, the heavy machine is further equipped with a spraying device for shotcrete, and the arch-shaped steel support installed at the erected position is gripped by the pair of hands. Then, after the temporary fixing step, the pair of sprayed concrete is sprayed onto the legs of the steel support by the spraying device to temporarily fix the steel support to the wall surface of the tunnel well. A holding release process for releasing the holding of the steel support by the hand, the steel support temporarily fixed to the tunnel pit wall surface, and the existing steel support adjacent to the steel support and the tunnel in the axial direction. A spraying step of spraying shot concrete with the work and embedding the entire length of the steel support construction in the longitudinal direction in the shot concrete.

  Further, the steel support has an H-shaped cross section, and an anchor member fixed to the spray concrete is provided on the leg web, and in the temporary fixing step, the anchor member is It may be buried in attached concrete. In this case, the anchor member may be provided on both sides of the web.

  Further, in the support connection step, the second top joint plate is guided by a guide member provided on the outer peripheral edge of the first top joint plate, and the male mold is inserted into the insertion port of the female joint. The locking member may be guided. In this case, the guide member may be provided so as to cover a part of the outer peripheral edge of the first top joint plate. Moreover, the said guide member may be provided in 2 sides which form a corner | angular part in the outer periphery of the said 1st top end joint board. In addition, the guide member faces the face when the pair of steel support members are connected, of the upper guide wall provided on the upper edge of the first top end joint plate and the first top end joint plate. And a side guide wall provided on the side edge of the side.

The first top end joint plate has a concave shape, and the second top end joint plate has a convex shape complementary to the concave shape of the first top end joint plate. The first top joint plate and the second top joint plate are formed in surface contact with each other when the pair of steel support members are connected, and in the support connection step, The male locking member may be guided by sliding along the concave surface of the first top joint plate, and the male locking member may be guided to the insertion port of the female connecting portion.

  Further, the female connecting portion is disposed in a most recessed area in the area of the first top joint plate having the concave shape, and the male locking member has the convex shape. You may arrange | position in the area | region which protruded most in the area | region of a 2nd top end joint board.

  The opening hole has a tapered surface that increases in diameter from the inner surface side to the outer surface side in the thickness direction of the first top end joint plate. In the support connection step, the first top end joint plate The male locking member may be guided by sliding along the tapered surface in the opening hole, and the male locking member may be guided to the insertion port of the female connecting portion.

  In addition, a tapered surface that is reduced in diameter toward the distal end is formed at the distal end portion of the male locking member, and in the support connection step, an edge portion in the opening hole of the first top end joint plate The male locking member may be guided by sliding the taper surface of the male locking member along the guide line, and the male locking member may be guided to the insertion port of the female connecting portion.

  ADVANTAGE OF THE INVENTION According to this invention, the construction method of the tunnel which can avoid the manual work in the face of a tunnel and can improve safety | security and workability | operativity can be provided.

FIG. 1 is a side view of a tunnel support according to the first embodiment. FIG. 2 is a diagram illustrating a fixing anchor according to the first embodiment. FIG. 3 is a diagram illustrating the tunnel support structure according to the first embodiment. FIG. 4 is a schematic configuration diagram of a tunnel support construction system according to the first embodiment. FIG. 5 is a top view of the work vehicle according to the first embodiment. FIG. 6 is a side view of the work vehicle according to the first embodiment. FIG. 7 is a diagram illustrating a position where the target is attached to the tunnel support according to the first embodiment. FIG. 8 is a diagram illustrating a target according to the first embodiment. FIG. 9 is a schematic diagram illustrating a connection structure that connects the left steel support and the right steel support according to the first embodiment. FIG. 10 is a diagram illustrating a first top joint plate according to the first embodiment. (A) shows the female connecting portion viewed from the outer surface side of the first top joint plate. (B) shows the female connecting portion viewed from the inner surface side of the first top joint plate. FIG. 11 is a diagram illustrating a second top end joint plate according to the first embodiment. The male type | mold connection part seen from the inner surface side of the 2nd top end joint board is shown to (a). (B) shows the male connecting portion viewed from the outer surface side of the second top joint plate. 12 is a cross-sectional view taken along the line XX in FIG. FIG. 13 is a diagram illustrating a state in which the female coupling portion and the male coupling portion according to the first embodiment are coupled to each other. FIG. 14 is a diagram illustrating a connection structure according to a modification of the first embodiment. FIG. 15 is a diagram for explaining a tunnel support construction procedure according to a modification of the first embodiment. FIG. 16 is a view for explaining a connecting structure of a steel support according to the second embodiment. (A) is a longitudinal cross-sectional view of the 1st top end joint board vicinity in the left side steel support. (B) is the A arrow front view of (a). (C) is a BB arrow directional cross-sectional view of (a). FIG. 17 is a diagram for explaining an operation when the left steel support and the right steel support are connected in the second embodiment. FIG. 18A is a diagram illustrating a guide member according to a modification of the second embodiment. FIG. 18B is a diagram illustrating a guide member according to a modification of the second embodiment. FIG. 19 is a view for explaining a connecting structure of a steel support according to the third embodiment. (A) is a longitudinal cross-sectional view of the 1st top end joint board vicinity in the left side steel support construction concerning Embodiment 3. FIG. (B) is a C arrow front view of (a). (C) is a schematic perspective view of the first top joint plate according to the third embodiment. FIG. 20 is a view for explaining a connecting structure of steel supporters according to the third embodiment. (A) is a longitudinal cross-sectional view of the vicinity of the second top end joint plate of the right steel support according to the third embodiment. (B) is a D arrow front view of (a). (C) is a schematic perspective view of the second top end joint plate according to the third embodiment. FIG. 21 is a diagram for explaining the operation when the left steel support and the right steel support are connected in the third embodiment. FIG. 22 is a view showing a modification of the left steel support and the right steel support. FIG. 23 is a diagram illustrating a modification of the fixing anchor.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Embodiment 1>
FIG. 1 is a side view of a tunnel support 10 according to the first embodiment. The tunnel support 10 is an arch-shaped steel support built along the pit wall immediately after excavation in order to prevent the collapse of exposed ground caused by tunnel excavation. Installed every time. The tunnel support 10 in this embodiment is formed of H-section steel having an H-shaped cross section. More specifically, the tunnel support 10 is formed in an arch shape by integrally connecting the top ends (upper ends) of the pair of arcuate steel supports 10L and 10R. Hereinafter, the steel support 10L is referred to as a “left steel support” and the steel support 10R is referred to as a “right steel support”.

  The left steel support 10 </ b> L includes a first main body 111, a first top joint plate 121, and a first bottom plate 131. The 1st main-body part 111 is the H-section steel comprised from the web 111a, a pair of ground mountain side flange 111b orthogonal to the said web 111a, and the inner space | flank side flange 111c. Further, a first top end joint plate 121 is welded to one end of the first main body 111, and a first bottom plate 131 is welded to the other end. The first top end joint plate 121 and the first bottom plate 131 are rectangular steel flat plates and extend in a direction orthogonal to the H-shaped cross section of the first main body 111. Similarly, the right steel support 10R includes the second main body 112, the second top joint plate 122, and the second bottom plate 132. The 2nd main-body part 112 is the H-section steel comprised from the web 112a, a pair of ground mountain side flange 112b orthogonal to the said web 112a, and the inner space side flange 112c. Further, the second top end joint plate 122 is welded to one end of the second main body portion 112, and the second bottom plate 132 is welded to the other end. The second top end joint plate 122 and the second bottom plate 132 are rectangular steel flat plates and extend in a direction orthogonal to the H-shaped cross section of the second main body 112. In the present embodiment, the first top joint plate 121 and the second top joint plate 122 have a congruent square plane. As shown in FIG. 1, the left steel support 10L and the right steel support 10R are connected in a state where the first top joint plate 121 and the second top joint plate 122 face each other.

Reference numeral 2 shown in FIG. 1 is a fixing anchor. The fixing anchor 2 is provided on each leg of the left steel support 10L and the right steel support 10R, and corresponds to an anchor member. In the present embodiment, the web 111a located at the leg 111d of the first main body 111 in the left steel support 10L and the web 112a located at the leg 112d of the second main body 112 in the right steel support 10R. Further, the fixing anchor 2 is projected. FIG. 2 shows the first main body 1
11 is a diagram illustrating the fixing anchor 2 provided on the eleven leg portions 111d and the leg portion 112d of the second main body portion 112. FIG. The fixing anchor 2 includes a shaft portion erected vertically from the webs 111a and 112a and a head portion provided at the tip of the shaft portion and having a diameter larger than that of the shaft portion. However, the shape of the fixing anchor 2 can be changed as appropriate. In the present embodiment, the first main body 111 has the fixing anchors 2 protruding on both surfaces of the web 111a. In the second main body 112, the fixing anchors 2 are convexly provided on both surfaces of the web 112a.

  FIG. 3 is a diagram illustrating the tunnel support structure 1 according to the first embodiment. The code | symbol 3 in FIG. 3 is a primary shotcrete layer. Moreover, the code | symbol 6 is a secondary shotcrete layer. In FIG. 3, the right side steel support 10 </ b> R of the tunnel support 10 is illustrated. In the tunnel construction method of this embodiment, after the ground 8 is exposed on the side surface of the tunnel T by excavation of the face 8, the primary concrete is sprayed onto the ground 7 so that the primary shotcrete is applied. Layer 3 is formed. Thereafter, the above-described arch-shaped tunnel support 10 is built on the inner side of the primary shotcrete 3 along the tunnel wall surface. The tunnel supporter 10 is adjacent to the face 8 side with respect to the existing tunnel supporter 10 located on the wellhead side of the tunnel T, and has a predetermined interval (for example, 1.0 m to 1.5 m) in the axial direction of the tunnel T. Degree). The tunnel supporter 10 is built using an erector apparatus including a hand attached to a pair of boom tips. Hereinafter, the construction method of the tunnel supporter 10 will be described in detail.

  FIG. 4 is a schematic configuration diagram of the erection system S of the tunnel support 10 according to the first embodiment. In the figure, reference numeral 100 denotes an erector apparatus for installing the tunnel supporter 10, and reference numeral 200 denotes a work vehicle (heavy machine) that can be self-propelled while the erector apparatus 100 is mounted. Reference numeral 300 denotes an automatic tracking total station that is a distance measuring / angle measuring instrument (surveying instrument) using laser light, reference numeral 400 denotes a total station controller that controls the total station 300, and reference numeral 500 denotes a total station side that enables wireless transmission and reception with the total station controller 400. It is an antenna.

  The erector apparatus 100 includes a monitor 101 that is a display device mounted on a cockpit, an erector controller 102, an erector-side antenna 103, an operation panel 104, a keyboard 105, a ponting device 106, and the like.

  The total station 300 is a surveying instrument that measures (measures) the position of the target 9 by automatically tracking the target 9 including a prism or the like by irradiating a laser beam and performing distance measurement and angle measurement. Are installed at points where the coordinates are known (coordinate known points). In this embodiment, the target 9 is attached to the tunnel support 10 (left steel support 10L and right steel support 10R) to be built in the face 8, and the tunnel support 10 (left steel support 10L and right steel made). Since the target 9 is automatically tracked along with the movement of the support work 10R), it is preferable to select and place such a target where there is no obstacle in automatic tracking and collimation. For example, it may be installed on a tunnel floor, or a stand may be installed on the ceiling, and the total station 300 may be installed on the stand.

  The total station controller 400 includes, for example, a portable computer. The total station controller 400 automatically controls various mechanisms of the total station 300 by software installed in a computer and processes survey data of the total station 300. Furthermore, the total station controller 400 can transmit and receive data by wireless communication with the erector controller 102 side, and can wirelessly operate various mechanisms of the total station 300 by commands from the erector controller 102 side. .

  FIG. 5 is a top view of the work vehicle 200 according to the first embodiment. FIG. 6 is a side view of the work vehicle 200 according to the first embodiment. The work vehicle 200 includes an erector device 100 and a spraying device 600. The erector apparatus 100 includes a pair of booms 17L and 17R having the same configuration. The pair of booms 17L and 17R can be freely expanded / contracted, tilted, oscillated, and rotated by operation of a drive mechanism attached thereto. In addition, a pair of hands 18L and 18R having the same configuration are connected to the tips of the booms 17L and 17R. The pair of hands 18L and 18R can freely rotate and swing by the operation of a drive mechanism attached thereto, and the left steel support 10L and the right steel support 10R can be detachably clamped. (Hold).

  Hereinafter, the boom indicated by reference numeral 17L is referred to as a “left boom”, and the boom indicated by reference numeral 17R is referred to as a “right boom”. A hand indicated by reference numeral 18L is referred to as a “left hand”, and a hand indicated by reference numeral 18R is referred to as a “right hand”. The erector apparatus 100 can detachably hold the left steel support 10L to the left hand 18L and detachably hold the right steel support 10R to the right hand 18R. In the present embodiment, the left steel support 10L and the right steel support 10R are a pair of support materials in which the arch-shaped tunnel support 10 is divided into two parts, and after being guided in the vicinity of the face 8, Are assembled at the face 8 to form an arch-shaped tunnel support 10.

  FIG. 7 is a diagram illustrating a position where the target is attached to the tunnel support according to the first embodiment. As shown in FIG. 7, the left-side steel support 10L and the right-side steel support 10R have a symmetrical arc shape. Here, the left steel support 10L has a first target 9a and a second target 9b attached to the upper end and the lower end, respectively. The right steel support 10R has a third target 9c and a fourth target 9d attached to the upper end and the lower end, respectively. Here, the first target 9a to the fourth target 9d are collectively referred to as “target 9”. FIG. 8 is a diagram illustrating the target 9 according to the first embodiment. The target 9 includes a magnet 92 provided at the base end portion of the holder 91 and a prism 93 provided at the tip of the holder 91. Since the left steel support 10L and the right steel support 10R are made of steel, the target 9 is attached to the left steel support 10L and the right steel support 10R by the magnetic force of the magnet 92 provided on the holder 91. It can be attached detachably.

  Moreover, in the example shown in FIG. 7, the target 9 is attached to the inner space side flanges 111c and 112c of the left steel support 10L and the right steel support 10R. In the present embodiment, marks for attaching each target 9 to the inner flanges 111c and 112c of the left steel support 10L and the right steel support 10R are preliminarily marked with paint or the like. Each target 9 has a fixed height Hp from its mounting surface to the center of the prism 93 in a state where it is attached to the inner flanges 111c and 112c of the left steel support 10L and the right steel support 10R. .

  Next, the spraying device 600 will be described with reference to FIGS. 5 and 6. The spray device 600 is disposed between the left boom 17L and the right boom 17R, and is provided with an arm 601, a spray robot 602 supported by the arm 601, and a spray provided on the tip side of the spray robot 602. A nozzle 603 and the like are provided. The arm 601 can be expanded and contracted, tilted, and the like. Further, the spraying robot 602 is capable of tilting and rotating the spray nozzle 603. In addition, the spraying device 600 includes a concrete pump, a quick setting agent supply device, a compressor, a high-pressure water pump, and the like. The spraying robot 602 can spray the sprayed concrete on the face 8 by discharging the sprayed concrete supplied from the concrete pump from the spray nozzle 603.

Next, the construction method of the tunnel support work 10 in this embodiment is demonstrated. NA
TM construction method: (1) Blasting face 8 or excavating by machine → (2) Unloading → (3) Spraying primary sprayed concrete → (4) Building tunnel support → (5) Secondary blowing Spraying of the attached concrete → (6) This is a method of extending the tunnel T in the axial direction by repeating the placement of the lock bolt as one cycle. In the present embodiment, (2) after the slip-out step is completed, the work vehicle 200 on which the erector device 100 is mounted is placed in the vicinity of the face 8 (elector placement step). At that time, each of the hands 18L and 18R of the erector apparatus 100 holds the work vehicle 200 in a state where the left steel support 10L and the right steel support 10R are gripped along the tunnel axis (tunnel extending direction). Run and place near the face 8 Then, the primary sprayed concrete layer is formed by spraying the primary sprayed concrete using the spraying device 600 to the ground 7 (tunnel wall surface) where the left steel support 10L and the right steel support 10R are to be built. 3 is formed.

  Next, the left steel support 10L and the right steel support 10R are driven by driving the hands 18L and 18R while holding the left steel support 10L and the right steel support 10R by the hands 18L and 18R. Are connected to each other at the top ends (supporting connection step). Hereinafter, the connection structure of the left steel support 10L and the right steel support 10R will be described.

  FIG. 9 is a schematic diagram illustrating a connection structure 30 that connects the left steel support 10L and the right steel support 10R according to the first embodiment. The connection structure 30 is a female connection that is recessed in the first top end joint plate 121 of the left steel support 10L, the second top end joint plate 122 of the right steel support 10R, and the first top end joint plate 121. Part 40, a male connecting part 50 and the like protruding from the second top joint plate 122. FIG. 2 shows a state before the first top joint plate 121 of the left steel support 10L and the second top joint plate 122 of the right steel support 10R are connected via the connection structure 30, that is, A state in which the first top end joint plate 121 and the second top end joint plate 122 are separated from each other is shown.

  Here, reference numeral 121a is the outer surface of the first top joint plate 121, and reference numeral 121b is the inner surface of the first top joint plate 12L. Reference numeral 122 a is an outer surface of the second top end joint plate 122, and reference numeral 122 b is an inner surface of the second top end joint plate 122. FIG. 10A shows the female connecting portion 40 viewed from the outer surface 121 a side of the first top end joint plate 121, and FIG. 10B shows the female joint portion 40 viewed from the inner surface 121 b side of the first top end joint plate 121. The female connection part 40 is shown. 11A shows the male connecting portion 50 viewed from the inner surface 122b side of the second top end joint plate 122, and FIG. 11B shows the view from the outer surface 122a side of the second top end joint plate 122. A female connecting part 40 is shown.

  Reference numeral 121 c is the upper edge of the first top end joint plate 121, reference numeral 121 d is the lower edge of the first top end joint plate 121, and reference numeral 121 e is the left and right side edges of the first top end joint plate 121. Reference numeral 122c denotes an upper edge of the second top end joint plate 122, reference numeral 122d denotes a lower edge of the second top end joint plate 122, and reference numeral 122e denotes left and right side edges of the second top end joint plate 122. FIG. 10 illustrates the height direction and the width direction of the first top joint plate 121, and FIG. 11 illustrates the height direction and the width direction of the second top end joint plate 122. The height direction of the first top end joint plate 121 is parallel to the extending direction of the side edge 121e, and is parallel to the extending direction of the web 111a at a position where the first main body 111 is connected to the first top end joint plate 121. It is. Further, the width direction of the first top end joint plate 121 is parallel to the extending direction of the upper edge 121 c and the lower edge 121 d, and the natural mountain side at the position where the first main body 111 is connected to the first top end joint plate 121. It is parallel to the extending direction of the flange 111b and the inner-side flange 111c. Further, the height direction of the second top end joint plate 122 is parallel to the extending direction of the side edge 122e, and the extending direction of the web 112a at a position where the second main body 112 is connected to the second top end joint plate 122. And parallel. The width direction of the second top end joint plate 122 is parallel to the extending direction of the upper edge 122c and the lower edge 122d, and the ground-side flange 112b at a position where the second main body 112 is connected to the second top end joint plate 122. And parallel to the extending direction of the inner-side flange 112c.

  As shown in FIGS. 10 (a) and 10 (b), the first top joint plate 121 has a female connecting portion 40 in each of a first area indicated by reference numeral A1 and a second area indicated by reference numeral A2. Is provided. The first area A1 is located on one side of the plane area of the first top end joint plate 121 with the web 111a of the first main body 111 as a boundary, and the natural ground side flange 111b, the inner air side flange 111c, and the web 111a. It is an area surrounded by. The second region A2 is located on the other side of the first top end joint plate 121 on the other side of the web 111a of the first main body 111, and the ground-side flange 111b, the inner-side flange 111c, and the web 111a. It is an area surrounded by. Similarly, as shown in FIGS. 11 (a) and 11 (b), the second top end joint plate 122 is connected to the first region indicated by reference numeral A1 and the second region indicated by reference numeral A2, respectively. A portion 40 is provided. The first region A1 is located on one side of the plane region of the second top end joint plate 122 with the web 112a of the second main body 112 as a boundary, and the natural ground side flange 112b, the inner air side flange 112c, and the web This is a region surrounded by 112a. The second region A2 is located on the other side of the plane region of the second top end joint plate 122 with the web 112a of the second main body 112 as a boundary, and the natural ground side flange 112b, the inner air side flange 112c, and the web This is a region surrounded by 112a.

  First, the male connection part 50 protruding from the second top end joint plate 122 will be described. The second top end joint plate 122 is formed with a pair of opening holes 122f at positions where the male connecting portions 50 are provided. The male connecting part 50 has a rod-shaped male locking member 51. The male locking member 51 is a shaft member having a slightly smaller diameter than the opening hole 122f of the second top end joint plate 122, and a male screw 51a is engraved at the base end portion thereof. In addition, an annular flange 51 b is provided in the middle portion of the male locking member 51. In addition, a male screw 51c is formed on the outer peripheral portion of the male locking member 51 at the front end side of the flange portion 51b. The male screw 51 c of the male locking member 51 is a circumferential male locking groove arranged in parallel on the outer periphery of the male locking member 51. Further, a tapered surface 51e having a diameter decreasing toward the tip is formed at the tip 51d of the male locking member 51.

  Further, a counterbore portion 122g that is recessed by one step from the periphery is formed around the opening hole 122f on the outer surface 122a side of the second top end joint plate 122. The flange 51 b of the male locking member 51 is larger than the diameter of the opening hole 122 f of the second top end joint plate 122. The base end of the male locking member 51 is inserted into the opening hole 122f from the outer surface 122a side of the second top end joint plate 122, and the base end male screw 51a is disposed in the counterbore portion 122g. A nut 52 is screwed onto the screw. As a result, the male locking member 51 can be fixed to the second top end joint plate 122 with the male locking member 51 protruding from the second top end joint plate 122.

  Next, the female connector 40 will be described. The first top joint plate 121 is provided with a pair of opening holes 121f at the position where the female connecting portion 40 is provided, and a metal cylindrical casing 41 is fixed to the inner surface 121b by welding wp or the like. Has been. The casing 41 has its axial center located substantially at the center of the opening hole 121f. A storage chamber 42 is formed in the casing 41. A tapered hole 43 having a tapered surface 43a whose inner diameter is gradually reduced from the rear end side to the front end side is formed in the front portion (front portion) of the storage chamber 42. In addition, a spring storage portion 42 a is formed in the intermediate portion of the storage chamber 42, and a female screw 45 is engraved on the inner periphery of the rear portion of the storage chamber 42. An insertion port 48 is formed at the tip of the tapered hole 43. The insertion port 48 located at the front end portion of the casing 41 has substantially the same diameter as the opening hole 121f formed in the first top end joint plate 121 and communicates with the opening hole 121f. Further, the insertion port 48 is disposed at a position where the casing 41 is fixed to the first top joint plate 121 and overlaps the opening hole 121f.

In the tapered hole 43, a divided female locking member 46 is slidably disposed in the axial direction. In the present embodiment, as shown in FIG. 12, a wedge-shaped female locking member 46 divided into three in the circumferential direction is disposed so as to be slidable in the axial (front-rear) direction of the casing 41. . Here, the outer surface of the female locking member 46 is formed as a tapered surface 46 a that can slide along the tapered surface 43 a in the tapered hole 43. The outer diameter of the tapered surface 46a of the female locking member 46 gradually increases from the tip side to the rear. Furthermore, a female screw 46 b is formed on the inner surface of each female locking member 46. The female screw 46b is a female locking groove in the circumferential direction provided in parallel on the inner surface of each female locking member 46. The female screw 46 b is an arc centered on the axis of the casing 41 and is engraved in a direction along the axis. As described above, a female screw hole is formed by the plurality of female locking members 46, and the taper surface 46 a of each female locking member 46 is retracted along the taper surface 43 a of the taper hole 43, so that the female screw The diameter of the female screw hole is reduced by expanding the diameter of the hole and moving it forward (forward). The female screw 46 b formed on the inner surface of each female locking member 46 can be engaged with a male screw 51 c formed on the outer peripheral portion on the distal end side of the male locking member 51.

  Further, in the spring storage portion 42 a of the storage chamber 42, a pressing spring 44, which is a pressing member that presses (elastically biases) the female locking member 46 forward (forward), is provided behind each female locking member 46. It is housed in a compressed state between a spring receiver 47 and a lid plate 49 provided at the end, and each female locking member 46 is always pushed forward by the pressing force of the pressing spring 44. The lid plate 49 can be held in a compressed state by being screwed onto a female screw 45 engraved on the rear inner peripheral side of the storage chamber 42. A hexagonal hole 49a is provided on the outer surface of the lid plate 49, and the lid plate 49 is detachable from the casing 41 with a hexagon wrench.

  In the female connecting part 40 and the male connecting part 50 configured as described above, the female screw 46b formed on the inner surface of each female locking member 46 and the outer peripheral part of the male locking member 51 are formed. The male screw 51c is formed so that the screw pitch is smaller than the pitch of fine screws defined in JIS. Further, in the female coupling portion 40 of the present embodiment, the helical female screw 46b is formed on the inner surface of each female locking member 46, but instead of the female screw 46b, the circumferential direction of each female locking member 46 Parallel grooves in which annular crests and annular troughs extending in parallel are arranged alternately and in parallel may be provided on the inner surface of each female locking member 46. Similarly, in the male connecting part 50, instead of the male screw 51c formed on the outer peripheral part of the male locking member 51, an annular peak and an annular valley extending in the circumferential direction of the male locking member 51 are provided. Parallel grooves arranged alternately and in parallel may be provided on the outer peripheral surface of the male locking member 51.

  Next, the operation of the connecting structure 30 when connecting the left steel support 10L and the right steel support 10R will be described. As shown in FIG. 9, the first top joint plate 121 in the left steel support 10L and the second top joint plate 122 in the right steel support 10R approach and face each other (opposite) from the first The separation distance between the first top end joint plate 121 and the second top end joint plate 122 is gradually increased so that the male connecting portion 50 (male locking member 51) is inserted into the opening hole 121f of the top end joint plate 121. Narrow to.

  Here, the outer diameter of the male locking member 51 is slightly smaller than the opening hole 121f of the first top end joint plate 121 and the insertion port 48 of the female coupling portion 40 (casing 41), and each female mold is formed. In a state where the locking member 46 is disposed at the most advanced position of the taper hole 43 (taper surface 43a), the diameter is set to be slightly larger than the diameter of the female screw hole formed by each female locking member 46. . When the male locking member 51 protruding from the second top end joint plate 122 enters from the insertion port 48 of the female connecting portion 40 through the opening hole 121f of the first top end joint plate 121, the pressing spring 44 is pushed. The front end portion 51d of the male locking member 51 comes into contact with the front end surface 46c of each female locking member 46 positioned at the most advanced position of the tapered hole 43 (tapered surface 43a) by the pressure. Then, the male locking member 51 resists the pressing force of the pressing spring 44, and each female locking member 46 is directed to the rear side in the axial direction of the female coupling portion 40 (casing 41) along the tapered surface 43 a. The male locking member 51 is inserted into the storage chamber 42 while expanding the diameter of the female screw hole formed by the female screw 46b of the tapered surface 46a of each female locking member 46.

  Then, the outer surface 121a of the first top end joint plate 121 and the outer surface 122a of the second top end joint plate 122 come into contact with each other to come into surface contact, and the male locking member into the storage chamber 42 in the female connecting portion 40 When the insertion of the male locking member 51 into the storage chamber 42 is stopped by completing the insertion of the 51, the female locking members 46 are moved forward (forward) by the pressing force of the pressing spring 44. ) And the female screw hole formed by the tapered surface 46a of each female locking member 46 is reduced in diameter. As a result, as shown in FIG. 13, the female screw 46 b (female side locking groove) of each female locking member 46 in the female connecting portion 40 and the male screw of the male locking member 51 in the male connecting portion 50. 51c (male side locking grooves) mesh with each other. As a result, as shown in FIG. 1, the left steel support 10L and the right steel support 10R are integrally connected with the first top joint plate 121 and the second top joint plate 122 in surface contact. Is done. In the present embodiment, each outer edge of the first top end joint plate 121 and the second top end joint plate 122 in a state where the male locking member 51 is inserted and locked to the female connecting portion 40. It is set so that the positions of each other match. That is, in the state where the female connecting portion 40 of the first top end joint plate 121 and the male locking member 51 of the second top end joint plate 122 are connected, the upper edge 121c of the first top end joint plate 121, the bottom The edge 121d and the pair of side edges 121e overlap the upper edge 122c, the lower edge 122d, and the pair of side edges 122e of the second top end joint plate 122, respectively.

  Here, as shown in FIG. 13, in the state where the female screw 46b of the female connecting portion 40 and the male screw 51c of the male connecting portion 50 (male locking member 51) are engaged, the first top joint plate When an external force acts in a direction separating the 121 and the second top end joint plate 122, a pulling force acts in a direction of pulling out the male locking member 51 from the storage chamber 42 in the female connecting portion 40. This pull-out force is transmitted to each female locking member 46 through a male screw 51c and a female screw 46b that are engaged with each other. By the way, the outer diameter of the tapered surface 46a of each female locking member 46 gradually decreases from the rear side to the front side. Therefore, even if the pulling force acts on each female locking member 46, the displacement of each female locking member 46 toward the front of the tapered hole 43 is limited. That is, according to the connection structure 30 according to the present embodiment, even if an external force acts in the direction in which the male locking member 51 is pulled out from the storage chamber 42 of the female connection portion 40, the connection state is maintained against the external force. Can be maintained. That is, according to the connection structure 30 in the embodiment, only the operation of inserting the male connection part 50 (male locking member 51) from the insertion port 48 of the female connection part 40 is performed with respect to the female connection part 40. Since the male connecting portion 50 is connected, the left steel support 10L and the right steel support 10R can be easily fastened together. Further, even if a pulling force acts in a direction in which the male locking member 51 is pulled out from the storage chamber 42 in the female connecting portion 40, the connection between the female connecting portion 40 and the male connecting portion 50 is prevented from being released. it can.

  Here, the operation of the erector apparatus 100 when the left steel support 10L and the right steel support 10R are connected and built will be described. When the left steel support 10L and the right steel support 10R are connected and built, the erector apparatus 100 extends and tilts the left boom 17L and the right boom 17R, and rotates the left hand 18L and the right hand 18R. The left steel support 10L and the right steel support 10R are moved so as to be orthogonal to the tunnel axis. The booms 17L and 17R and the hands 18L and 18R in the erector apparatus 100 can be driven by operating the operation panel 104.

Next, the pair of hands 18L and 18R in a state where the left steel support 10L and the right steel support 10R are gripped are relatively moved so as to be recessed in the first top joint plate 121 and the left steel support 10L. The female connecting portion 40 provided and the male connecting portion 50 (male locking member 51) protruding from the second top end joint plate 122 of the right steel support 10R are connected to each other, and the left steel The tunnel supporter 10 is formed by connecting the supporter 10L and the right steel supporter 10R in an arch shape. At that time, the hands 18L and 18R are based on the survey data obtained by surveying the positions of the targets 9 attached to the left steel support 10L and the right steel support 10R from the coordinate known points.
Set the relative movement amount of and drive. In the present embodiment, the female connecting portion 40 is provided in a recessed manner in the first top end joint plate 121 of the left steel support 10L, and the second top end joint plate 122 is provided in a right steel support 10R. The male connecting part 50 (male locking member 51) functions as a one-touch joint that is connected by one-touch by the hand operation of the erector apparatus 100.

  For example, the erector controller 102 wirelessly operates the total station 300 via the total station controller 400, automatically tracks each target 9 (first target 9a to fourth target 9d), and sequentially automatically measures the coordinates of each target 9 To do. Here, the total station 300 is installed at a coordinate known point (x0, y0, z0). In this way, by irradiating the laser beam from the total station 300 installed at the coordinate known point and collimating each target 9 to perform distance measurement and angle measurement, the position coordinates of the first target 9a to the fourth target 9d ( x1, y1, z1), (x2, y2, z2), (x3, y3, z3), (x4, y4, z4) can be obtained. The survey data including the position coordinates of each target 9 is sequentially wirelessly transmitted from the total station controller 400 side to the erector controller 102. The erector controller 102 sets the respective driving amounts for moving the hands 18L and 18R relative to each other based on the survey data of each target 9 acquired from the total station 300, and the left steel as described with reference to FIGS. The first top end joint plate 121 of the supporter 10L and the second top end joint plate 122 of the right side steel supporter 10R are connected to each other.

  The movement amounts of the hands 18L and 18R set by the erector controller 102 are displayed on the monitor 101. The total station 300 in this embodiment can automatically track and collimate each target 9. Accordingly, the amount of movement of each hand 18L, 18R required to interconnect the top ends of the left steel support 10L and the right steel support 10R by operating the hands 18L, 18R is displayed on the monitor 101 in real time. The operator can easily connect the left steel support 10L and the right steel support 10R by sequentially operating the operation panel 104 while looking at the monitor 101. In addition, the operation of the hands 18L and 18R referred to here includes operating the driving mechanisms of the hands 18L and 18R to directly operate the hands 18L and 18R, and the boom 17L to which the hands 18L and 18R are attached. , 17R by driving the hands 18L, 18R indirectly.

  After assembling the tunnel support 10 in an arch shape as described above, the erector apparatus 100 drives the hands 18L and 18R to place the tunnel support 10 at a predetermined built-in position in the vicinity of the face 8 (support Construction process). For example, the erector controller 102 determines each position of the first target 9a to the fourth target 9d based on survey data including the coordinate position of each target 9 (first target 9a to fourth target 9d) acquired from the total station 300. May be displayed on the monitor 101. Further, the monitor 101 may display the target positions of the first target 9a to the fourth target 9d in addition to the positions of the first target 9a to the fourth target 9d. An operator who operates the erector apparatus 100 can place the tunnel supporter 10 at a normal built-in position by driving the booms 17L and 17R and the hands 18L and 18R while looking at the monitor 101.

Here, after the tunnel supporter 10 (the left steel supporter 10L and the right steel supporter 10R) is arranged at a predetermined erected position on the face 8, the tunnel supporter 10 is placed on each hand 18L, 18R of the erector apparatus 100. With the left steel support 10L and the right steel support 10R gripped (held), the leg 111d of the left steel support 10L and the right steel support from the spray nozzle 603 of the spray device 600. 10R leg portion 112d (see FIG. 1) and the surrounding tunnel well wall surface (primary sprayed concrete layer 3) are sprayed with secondary sprayed concrete so that the tunnel support 10 is temporarily applied to the tunnel well wall surface. Fix (temporary fixing step). In the present embodiment, steel fiber reinforced concrete (SFRC) is used as the secondary shotcrete.

  After temporarily fixing the tunnel support 10 to the tunnel pit wall as described above, the gripping of the tunnel support 10 by the hands 18L and 18R of the erector apparatus 100 is released (gripping release step). Here, the leg portions 111d and 112d of the tunnel support 10 in the present embodiment are such that the fixing anchor 2 protrudes from the web 111a and the web 112a, and when the tunnel support 10 is temporarily fixed to the tunnel pit wall surface. The secondary spray concrete is sprayed so that the anchor 2 is buried in the secondary spray concrete. Thereby, the fixing property between the leg parts 111d and 112d of the tunnel supporting work 10 and the secondary shotcrete becomes very excellent. As a result, when the hands 18L and 18R are removed from the new tunnel support 10 even if the connecting material is bridged between the new tunnel support 10 that is adjacent to the tunnel T in the axial direction and the existing tunnel support 10 is not connected to each other. Further, it is possible to suitably suppress the inclination of the newly installed tunnel supporter 10 from tilting or falling. In particular, in this embodiment, the fixing anchors 2 are protruded on both surfaces of the webs 111a and 112a of the leg portions 111d and 112d of the tunnel support work 10, so that the two legs 111d and 112d of the tunnel support work 10 are connected. It becomes easier to secure the fixing force between the next shotcrete. Moreover, the stable support structure 1 can be constructed | assembled by increasing the fixing force between the tunnel support work 10 and the secondary shotcrete layer 6. FIG.

  Next, the secondary shotcrete is sprayed between the new tunnel support 10 adjacent to the tunnel T in the axial direction and the existing tunnel support 10 (new section), and the longitudinal direction of the new tunnel support 10 By embedding the entire area in the secondary shotcrete, the newly installed tunnel support 10 is fixed to the tunnel pit wall surface (primary shotcrete layer 3) (spraying step). As a result, a secondary shot concrete layer 6 having a predetermined thickness is formed on the inner side of the primary shot concrete layer 3. In the spraying process, the secondary spray concrete is sprayed to a thickness that substantially reaches the inner flanges 111 c and 112 c in the tunnel support work 10. Next, one cycle of the construction of the tunnel T is completed by driving a rock bolt through the secondary shot concrete layer 6 and the primary shot concrete layer 3 and placing it in the natural ground 7.

  As described above, according to the construction method of the tunnel T in the present embodiment, while holding the left steel support 10L and the right steel support 10R with the pair of hands 18L, 18R in the erector apparatus 100, the hands 18L, By driving 18R, the female connecting portion 40 recessed in the first top joint plate 121 and the male connecting portion 50 projecting from the second top joint plate 122 are engaged, and the left steel is made. The top end joint plates of the support 10L and the right steel support 10R can be connected in an arch shape. According to this, as in the prior art, personnel are placed in the work scaffolding and the man cage of the erector apparatus assembled near the face, and the personnel are moved to the vicinity of the top of the tunnel, to the top of the pair of steel support works. Since it is not necessary to perform manual work in the vicinity of the working face, such as fastening the joint plates positioned with bolts and nuts, safety and workability can be improved as compared with the prior art. Further, according to the connection structure 30 of the tunnel support 10 in the present embodiment, the female connection portion 50 (male locking member 51) is simply inserted through the insertion port 48 of the female connection portion 40, and the female connection portion 40 is inserted. Since the male connection part 50 can be engaged with the mold connection part 40, the connection work of the left steel support 10L and the right steel support 10R can be easily performed in a shorter time.

Moreover, according to the construction method of the tunnel T in the present embodiment, the left steel support 10L and the right steel support 10R are gripped by the pair of hands 18L, 18R of the erector apparatus 100 mounted on the work vehicle 200. Since the spraying concrete is sprayed from the spray nozzle 603 of the spraying device 600, the left steel supporter 10L and the right steel supporter 10R can be temporarily fixed at the regular built-in positions, so that it is conventional. The step of connecting the tunnel supporters 10 adjacent to each other in the axial direction of the tunnel T with the connecting material can be omitted. According to this, since it is not necessary to place personnel in the work scaffolds and the man cage of the elector device assembled near the face, it is not necessary to perform the installation work of the connecting material. Can be improved.

  In the present embodiment, as shown in FIG. 9, a tapered surface 51 e whose diameter decreases toward the tip is formed on the tip 51 d of the male locking member 51. For this reason, in the support connection process of connecting the left steel support 10L and the right steel support 10R (the female connection 40 and the male connection 50), the insertion port 48 of the female connection 40 Even if the center position of the male locking member 51 is slightly shifted, the tapered surface 51e of the male locking member 51 slides along the edge of the opening hole 121f of the first top joint plate 121. By doing so, the male locking member 51 can be guided in a direction in which the amount of displacement between the centers of the insertion port 48 and the male locking member 51 in the female connecting portion 40 decreases. That is, by providing the tapered surface 51e at the tip 51d of the male locking member 51, the left steel support 10L and the right steel support 10R (the female connection part 40 and the male connection part 50) are connected. In this case, the male locking member 51 can be smoothly guided to the insertion port 48 of the female connection part 40 even if the insertion position 48 of the female connection part 40 and the planar position of the male locking member 51 are slightly shifted. Can do. The details of the tapered surface 51e formed at the tip 51d of the male locking member 51 can be changed as appropriate. For example, the tip 51d of the male locking member 51 may be formed in a conical shape. In this case, the conical side surface is formed as a tapered surface 51e.

<Modification of the connection structure of Embodiment 1>
FIG. 14 is a diagram illustrating a connection structure 30 according to a modification of the embodiment. The opening hole 121f formed in the first top end joint plate 121 according to this modification has a tapered surface 1215 whose diameter increases from the inner surface 121b to the outer surface 122a in the thickness direction of the first top end joint plate 121. . Thus, by forming the opening hole 121f of the first top end joint plate 121, the left steel support 10L and the right steel support 10R (the female connecting part 40 and the male connecting part 50) are connected. At this time, even if the insertion port 48 of the female mold connecting portion 40 and the center position of the male locking member 51 are slightly shifted relative to each other, the tapered surface 1215 in the opening hole 121f of the first top joint plate 121 is made to be male. By sliding the mold locking member 51, the male locking member 51 is guided in a direction in which the amount of positional deviation between the insertion port 48 and the center of the male locking member 51 in the female coupling portion 40 is reduced. Can do. According to this, the male locking member 51 can be smoothly guided to the insertion port 48 of the female connecting portion 40.

<The modification of the support construction method of Embodiment 1>
Next, a modified example of the method for building the tunnel support 10 in the first embodiment will be described. FIG. 15 is a diagram for explaining a construction procedure of the tunnel support 10 according to the modification of the first embodiment. First, in step S101, the left steel support 10L and the right steel support 10R are held by the hands 18L and 18R in the erector apparatus 100. At this time, the gripping positions of the left steel support 10L and the right steel support 10R in each of the hands 18L and 18R are not strictly defined. For example, the left steel support placed on a support cradle (not shown). The approximate positions of the work 10L and the right steel support 10R may be held by the hands 18L and 18R.

Next, in step S102, the pair of hands 18L and 18R in a state of gripping the left steel support 10L and the right steel support 10R are relatively moved, and the first top joint of the left steel support 10L is moved. The female connecting portion 40 recessed in the plate 121 and the male connecting portion 50 (male locking member 51) protruding from the second top joint plate 122 of the right steel support 10R are connected to each other. Then, the tunnel support 10 is formed by connecting the left steel support 10L and the right steel support 10R in an arch shape (support connection step). In addition, in the built-in position (design position) where the left steel support 10L and the right steel support 10R are to be built, the support foot is sufficiently dug, for example, the built-in position (design The top edge of the left steel support 10L and the right steel support 10R at a position about several tens of centimeters (for example, about 20 cm) and about tens of centimeters (for example, about 20 cm) before (the wellhead side). Connect.

  Next, in step S103, one of the pair of hands 18L and 18R in the erector apparatus 100 is made free. For example, the holding of the right steel support 10R by the hand 18R is released. Then, in a state in which the grip of the right steel support 10R by the hand 18R is released, the hand 18L is driven and the leg portion of the left steel support 10L in the tunnel support 10 connected in an arch shape (for example, the first The bottom plate 131) is moved to the design position. In other words, the left steel support 10L is built in the design position (support build-in process). After that, in step S104, secondary shotcrete is sprayed on the legs of the left steel support 10L built in the design position, and the legs of the left steel support 10L are temporarily fixed to the tunnel pit wall surface. (Temporary fixing step)

  Next, in step S105, the holding of the left steel support 10L by the hand 18L is released, and the right steel support 10R is held by the hand 18R. Then, in a state where the grip of the left steel support 10L by the hand 18L is released, the hand 18R is driven, and the leg portion of the right steel support 10R in the tunnel support 10 connected in an arch shape (for example, the second The bottom plate 132) is moved to the design position. That is, the leg portion of the right-side steel support 10R is built at the design position (supporting build-in step). After that, in step S106, secondary shotcrete is sprayed on the leg of the right steel support 10R built in the design position, and the leg of the right steel support 10R is temporarily fixed to the tunnel pit wall surface. (Temporary fixing step)

  Next, in step S107, the holding of the right steel support 10R by the hand 18R is released. Thereby, both of the pair of hands 18L and 18R by the erector apparatus 100 are in a state of being detached from the tunnel supporter 10. Thereafter, in step S108, the secondary shotcrete is sprayed onto the section from the shoulder portion of the tunnel support 10 to the top end, and the entire longitudinal direction of the newly installed tunnel support 10 is embedded in the secondary shotcrete (blowout). Attaching process).

  According to the erection procedure of the tunnel support 10 described with reference to FIG. 15, in the state in which one of the left steel support 10L and the right steel support 10R is free, the other erection and the blowing of concrete to the legs are performed. In this case, the erection work for the left steel support 10L and the right steel support 10R and the spraying work to the legs were sequentially performed. According to this, it is possible to suppress an excessive force from the hands 18L, 18R acting on the left steel support 10L and the right steel support 10R. Therefore, it can suppress suitably that the connection structure 30 of 10 L of left side steel support works and the right steel support work 10R is damaged. In addition, in FIG. 15, although the case where the left steel support 10L was built prior to the right steel support 10R and the spraying to the legs was described as an example, the order may be changed. . That is, prior to the left steel support 10L, the right steel support 10R may be built and sprayed onto the legs.

<Embodiment 2>
Next, Embodiment 2 of the present invention will be described. FIG. 16 is a view for explaining a connecting structure of a steel support according to the second embodiment. FIG. 16 shows the first top end joint plate 121 and its peripheral structure of the left steel support 10L provided with the female connecting portion 40 out of the left steel support 10L and the right steel support 10R. Yes. FIG. 16A is a longitudinal sectional view of the vicinity of the first top end joint plate 121 in the left steel support 10L. FIG. 16B is a front view as seen from the arrow A in FIG. FIG.16 (c) is BB arrow sectional drawing of Fig.16 (a). Although not shown in FIG. 16, the right steel support 10R in the present embodiment has the same structure as that of the first embodiment. Further, the female connecting portion 40 and the second top end joint plate 12 that are recessed in the first top end joint plate 121 are provided.
The male connecting part 50 (male locking member 51) that protrudes to 2 has the same structure as that of the first embodiment.

  As shown in FIGS. 16A to 16C, a guide member 70 is provided on the outer peripheral edge of the first top joint plate 121 according to the second embodiment. The guide member 70 has a substantially trumpet shape as a whole, and is provided so as to cover the outer peripheral edge of the first top end joint plate 121. The guide member 70 has an upper guide wall 71, a lower guide wall 72, and a pair of side guide walls 73 each formed of a flat steel plate. As illustrated, the upper guide wall 71 extends from the upper edge 121 c of the first top end joint plate 121 in the vertical direction with respect to the first top end joint plate 121. On the other hand, the lower guide wall 72 extends obliquely from the lower edge 121d of the first top joint plate 121 with respect to the first top joint plate 121, and the pair of side guide walls 73 serve as the first top joint plate. The side edge 121e of 121 extends in an oblique direction with respect to the first top joint plate 121.

  Next, the operation | movement at the time of connecting the left steel support 10L and the right steel support 10R in Embodiment 2 is demonstrated. FIG. 17 is a diagram illustrating an operation when connecting the left steel support 10L and the right steel support 10R in the second embodiment. In the support connection step of connecting the left steel support 10L and the right steel support 10R (the female connection 40 and the male connection 50), the guide member 70 guides the second top joint plate 122. The male locking member 51 of the male connecting portion 50 is guided to the insertion port 48 of the female connecting portion 40. The connection structure 30 in the present embodiment is recessed in the first top joint plate 121 of the left steel support 10L, the second top joint plate 122, and the first top joint plate 121 of the right steel support 10R. The female connection part 40, the male connection part 50 protruding from the second top joint plate 122, and the guide member 70 are included.

  In the example shown in FIG. 17, the lower edge 122 d of the second top end joint plate 122 of the right steel support structure 10 </ b> R abuts on the lower guide wall 72 of the guide member 70 and slides on the surface of the lower guide wall 72. Accordingly, the amount of shift in the height direction between the insertion port 48 (the opening hole 121f of the first top end joint plate 121) in the female connecting portion 40 and the center of the male locking member 51 in the male connecting portion 50 gradually increases. Decrease. Further, in the present embodiment, the insertion port 48 and the male locking member in the female coupling portion 40 in a state where the upper edge 122c of the second top end joint plate 122 is in contact with the upper guide wall 71 of the guide member 70. The amount of deviation in the height direction between the centers of 51 is set to be zero. Moreover, although not shown in FIG. 17, in the process in which the left steel support 10L and the right steel support 10R are relatively approached, the second top end joint plate 122 of the right steel support 10R By sliding the side edge 122e along the surface of the side guide wall 73 of the guide member 70, the insertion port 48 (the opening hole 121f of the first top end joint plate 121) and the male connection are formed in the female connection portion 40. The amount of shift in the width direction between the centers of the male locking members 51 in the portion 50 gradually decreases.

  As described above, in the guide member 70 according to the present embodiment, the effective area surrounded by the guide member 70 gradually increases from the distal end side to the proximal end side (the connection end with the first top end joint plate 121) of the guide member 70. It is squeezed. Therefore, when the left steel support 10L and the right steel support 10R are connected, the first top joint plate 121 and the second top joint plate 122 are gradually brought closer to each other, so that the outside of the first top joint plate 121 is removed. A guide member 70 provided at the periphery guides the second top end joint plate 122. Thereby, the centers of the insertion port 48 and the male locking member 51 in the female connecting part 40 are aligned. That is, the male locking member 51 can be guided to the insertion port 48 (the opening hole 121f of the first top end joint plate 121) of the female connecting part 40. Then, by inserting the male locking member 51 from the insertion port 48 of the female connecting part 40, the connection of the left steel support 10L and the right steel support 10R is completed.

In the guide member 70 according to the present embodiment, the upper guide wall 71 extends in the vertical direction from the upper edge 121 c of the first top end joint plate 121 to the first top end joint plate 121. As a result, the upper guide wall 71 of the guide member 70 becomes the upper edge 121c of the first top end joint plate 121.
It does not protrude greatly from the outside. This makes it difficult for the upper guide wall 71 of the guide member 70 to interfere (collision) with the top end of the tunnel pit wall during the connecting operation of the left steel support 10L and the right steel support 10R. Can do. However, the guide member 70 is not particularly limited to the above shape, and the male locking member 51 is located at the position of the insertion port 48 in the female connecting portion 40 when the left steel support 10L and the right steel support 10R are connected. If it can guide so that it may approach, various shapes are employable. For example, the guide member 70 described above has a trumpet shape and has a shape that spreads from the base end side to the tip end side, but is not limited thereto. Further, the guide member 70 may be provided on a part of the outer peripheral edge of the first top end joint plate 121.

<Modification of Embodiment 2>
Here, FIG. 18A and FIG. 18B are diagrams showing a guide member according to a modification of the second embodiment. The guide member 70A shown in FIG. 18A includes an upper guide wall 71A and a lower guide that project vertically from the four sides (four surfaces) of the outer peripheral edge of the first top end joint plate 121 to the first top end joint plate 121. It has a wall 72A and a pair of side guide walls 73A. Here, the upper guide wall 71A of the guide member 70A is erected at the center of the upper edge 121c of the first top end joint plate 121, and the lower guide wall 72A is the center of the lower edge 121d of the first top end joint plate 121. The pair of side guide walls 73 </ b> A are erected at the center of each side edge 121 e of the first top end joint plate 121. In the example shown in FIG. 18A, the width dimensions of the upper guide wall 71A, the lower guide wall 72A, and the side guide wall 73A are respectively the upper edge 121c, the lower edge 121d, and the side edge 121e of the first top end joint plate 121. It is set smaller than the length of the side, and a gap G is formed between the upper guide wall 71A and the side guide wall 73A and between the lower guide wall 72A and the side guide wall 73A of the guide member 70A. Is formed.

  As described above, the guide member 70A shown in FIG. 18A does not cover the entire outer periphery of the first top end joint plate 121, but covers only a part of the outer periphery of the first top end joint plate 121. According to this, at the time of connecting the left steel support 10L and the right steel support 10R, the operator of the erector apparatus 100 looks at the female connecting part 40 recessed in the first top joint plate 121. easy.

  In the guide member 70A shown in FIG. 18A, the protrusion of the guide member 70A (the height of the upper guide wall 71A, the lower guide wall 72A, and the pair of side guide walls 73A) with respect to the outer surface 121a of the first top end joint plate 121. The dimension is set to be larger than the protruding length of the male locking member 51 protruding from the outer surface 122 a of the second top end joint plate 122. Accordingly, when the left steel support 10L and the right steel support 10R are connected, the second top end joint plate 122 is preferably guided by the guide member 70A, and the male connection portion 40 is positioned at the position of the insertion port 48. The mold locking member 51 can be smoothly guided. For example, the protruding dimension of the guide member 70 </ b> A with respect to the outer surface 121 a of the first top end joint plate 121 is about 20 to 30 mm larger than the protruding length of the male locking member 51 with respect to the outer surface 122 a of the second top end joint plate 122. You may set to a dimension.

  Next, the guide member 70B shown in FIG. 18B will be described. The guide member 70 </ b> B has guide walls provided on two sides (two surfaces) forming corners on the outer peripheral edge of the first top end joint plate 121. Specifically, the guide member 70 </ b> B is an upright guide wall 71 </ b> B standing from the upper edge 121 c of the first top end joint plate 121 and one side edge 121 e of the first top end joint plate 121. A side guide wall 73B is provided. Here, as shown in FIG. 18B, the width dimension of the upper guide wall 71A is smaller than the length of the upper edge 121c in the first top end joint plate 121 provided with the upper guide wall 71A. Moreover, the width dimension of the side guide wall 73B is smaller than the length of the side edge 121e in the 1st top end joint board 121 in which the said side guide wall 73B is provided.

  Since the guide member 70B shown in FIG. 18B is composed of an upper guide wall 71B and a side guide wall 73B projecting from two sides forming the corner portion of the outer peripheral edge of the first top joint plate 121, The gap G formed between the upper guide wall 71B and the side guide wall 73B can be further ensured. Therefore, the visibility of the female connection part 40 at the time of connection of the left steel support 10L and the right steel support 10R can be further enhanced. Further, since the corners are formed by the upper guide wall 71B and the side guide wall 73B orthogonal to each other, the upper portion of the second top end joint plate 122 is connected when the left steel support 10L and the right steel support 10R are connected. The second top joint plate 122 can be guided to an appropriate position by making the corner portion formed by the edge 122c and the side edge 122e abut against the above-mentioned corner portion. As a result, the male locking member 51 can be suitably guided to the insertion port 48 of the female connecting part 40, and the left steel support 10L and the right steel support 10R can be connected smoothly.

  Note that the side guide wall 73B in the guide member 70B shown in FIG. 18B faces the face 8 (that is, faces the erector apparatus 100) when the left steel support 10L and the right steel support 10R are connected. It is installed on the side edge 121e. According to the guide member 70B in the present embodiment, the lower edge 121d of the first top end joint plate 121 and the side edge 121e of the side not facing the face 8 (that is, the side facing the elector device 100) are guided. Since it is not covered with the wall and is open, the operator of the erector apparatus 100 connects the female joint 40 of the first top joint plate 121 when the left steel support 10L and the right steel support 10R are connected. It becomes easier to see.

<Embodiment 3>
Next, a third embodiment of the present invention will be described. FIG.19 and FIG.20 is a figure explaining the connection structure of the steel support construction which concerns on Embodiment 3. FIG. FIG. 19 shows a peripheral structure of the first top end joint plate 121 of the left steel support 10L according to the third embodiment. FIG. 20 shows a peripheral structure of the second top end joint plate 122 of the right-side steel support 10R according to the third embodiment.

  FIG. 19A is a longitudinal sectional view of the vicinity of the first top end joint plate 121 in the left steel support 10L according to the third embodiment. FIG.19 (b) is a front view seen from the arrow C of Fig.19 (a). FIG. 19C is a schematic perspective view of the first top joint plate 121 according to the third embodiment. FIG. 20A is a longitudinal sectional view of the vicinity of the second top end joint plate 122 of the right steel support 10R according to the third embodiment. FIG.20 (b) is a front view seen from the arrow D of Fig.20 (a). FIG. 20C is a schematic perspective view of the second top joint plate 122 according to the third embodiment. In addition, in FIG.19 (c), illustration of the 1st main-body part 111 in the left side steel support 10L is abbreviate | omitted. Moreover, in FIG.20 (c), illustration of the 2nd main-body part 112 in the right side steel support 10R is abbreviate | omitted.

  The first top joint plate 121 of the left steel support 10L in Embodiment 3 has a concave shape S1. Further, the second top end joint plate 122 of the right steel support 10R according to the third embodiment has a convex shape S2 complementary to the concave shape S1, and the left steel support 10L and the right steel support. The first top end joint plate 121 and the second top end joint plate 122 are configured to be in surface contact with each other when the work 10R is connected.

More specifically, the first top joint plate 121 has a folded plate structure that is folded into a substantially V shape (valley shape) so that the outer surface 121a side is a concave surface (concave surface shape S1). The outer surface 121 a of the first top joint plate 121 includes a flat concave bottom surface portion 1210, and an upper slope portion 1211 and a lower slope portion 1212 formed on both sides of the concave bottom surface portion 1210. With the flat concave bottom surface portion 1210 as a reference, the inclination angles of the upper slope portion 1211 and the lower slope portion 1212 with respect to the concave bottom surface portion 1210 are equal. On the other hand, the second top joint plate 122 has a folded plate structure that is folded into a substantially V shape (mountain shape) so that the outer surface 122a side becomes a convex surface (convex surface shape S2). The outer surface 122a of the second top end joint plate 122 includes a flat convex top surface portion 1220, and an upper slope portion 1221 and a lower slope portion 1222 formed on both sides of the convex top surface portion 1220.

  Here, the pair of female connecting portions 40 provided on the first top joint plate 121 are arranged on the concave bottom surface portion 1210. Here, the concave bottom surface portion 1210 is a relatively concave region in the first top joint plate 121 having the concave shape S1. The pair of male connecting portions 50 (male locking members 51) provided on the second top end joint plate 122 are arranged on the convex top surface portion 1220. Here, the convex top surface portion 1220 is a relatively raised region in the second top end joint plate 122 having the convex shape S2. Further, the female connecting part 40 and the male connecting part 50 are the same as those in the first and second embodiments. In the present embodiment, when the male locking member 51 is inserted and locked with respect to the female connecting portion 40, the outer edges of the first top end joint plate 121 and the second top end joint plate 122 All the positions are matched, and the outer surface 121a of the first top joint plate 121 and the outer surface 122a of the second top joint plate 122 are in surface contact. More specifically, the concave bottom surface portion 1210, the upper slope portion 1211, and the lower slope portion 1212 of the first top end joint plate 121 are respectively the convex top surface portion 1220, the upper slope portion 1221, and the lower slope portion of the second top end joint plate 122. It is adjusted so as to make surface contact with 1222 without causing a gap.

  FIG. 21 is a diagram illustrating an operation when connecting the left steel support 10L and the right steel support 10R in the third embodiment. As shown in the drawing, in the connecting structure of the steel support in this embodiment, when connecting the left steel support 10L and the right steel support 10R, along the concave surface of the first top joint plate 121. The male locking member 51 of the male connecting portion 50 slides. In the example shown in FIG. 21, the male engaging member 51 of the male connecting part 50 is guided by sliding along the surface of the upper slope part 1211 in the right steel support 10R, and the female connecting part 40 is guided. The male locking member 51 is guided in a direction in which the centers of the insertion port 48 and the male locking member 51 coincide. Thus, the male locking member 51 can be smoothly inserted into the storage chamber 42 from the insertion port 48 in the female coupling part 40, and the male locking member 51 is engaged with the female coupling part 40. can do.

  In the present embodiment, the female connecting portion 40 is disposed on the concave bottom surface portion 1210 which is the most concave region of the first top end joint plate 121 having the concave shape S1, and the second shape having the convex shape S2. In the second top end joint plate 122 having the convex shape S2 which is the most raised region of the top end joint plate 122, the male connecting portion 50 (male type) is connected to the convex top surface portion 1220 which is the relatively highest raised region. The locking member 51) is arranged. According to this, in the support connection step of connecting the left steel support 10L and the right steel support 10R (the female connecting part 40 and the male connecting part 50), the concave surface of the first top joint plate 121 is provided. When the male locking member 51 is guided along, the male locking member 51 can be guided more smoothly with respect to the insertion port 48 of the female connecting portion 40. In the example shown in FIG. 20, an example in which the upper slope portion 1211 of the first top end joint plate 121 functions as a guide surface of the male locking member 51 is shown. The lower inclined surface portion 1212 may function as a guide surface of the male locking member 51 by sliding the male locking member 51 along the portion 1212. In addition, the structure of the female type | mold connection part 40 in this embodiment and the male type | mold connection part 50 is the same as that of the above-mentioned embodiment.

  Further, as shown in FIG. 21, in a state where the male locking member 51 is fastened to the female connecting portion 40, the outer surface 121a of the first top end joint plate 121 and the outer surface 122a of the second top end joint plate 122 are Surface contact. That is, the concave bottom surface portion 1210, the upper inclined surface portion 1211 and the lower inclined surface portion 1212 of the first top end joint plate 121 are respectively connected to the convex top surface portion 1220, the upper inclined surface portion 1221 and the lower inclined surface portion 1222 of the second top end joint plate 122. Because of the surface contact, the stress transmission between the first top end joint plate 121 and the second top end joint plate 122 can be reliably performed. In the example shown in FIG. 19 to FIG. 21, the case where the concave shape S1 of the first top joint plate 121 and the convex shape S2 of the second top joint plate 122 are substantially V-shaped in a complementary relationship has been described. However, various combinations can be adopted for the concave shape S1 and the convex shape S2.

  Moreover, although the example shown in FIG. 1 mentioned above demonstrated the example which provides the fixing anchor 2 only in each leg part 111d, 112d of 10L of left side steel support works, and 10R of right side steel support works, it is not restricted to this. . For example, as shown in FIG. 22, the anchors 2 may be installed on the webs 111a and 112a over substantially the entire area in the longitudinal direction (stretching direction) of the left steel support 10L and the right steel support 10R. . 22 shows an example in which the fixing anchors 2 are arranged in two rows along the extending direction of the webs 111a and 112a. However, the arrangement pattern of the fixing anchors 2 is not particularly limited.

  Moreover, the fixing anchor 2 installed in the left steel support 10L and the right steel support 10R can employ various shapes. FIG. 23 is a view showing a modified example of the fixing anchor 2. FIG. 23A shows an example in which the straight bar-shaped fixing anchor 2 is projected from the web 111a (web 112a) of the first main body 111 (second main body 112). FIG. 23B shows an example in which a hook-shaped fixing anchor 2 with a hook provided with a hook at the tip is provided protruding from the web 111a (web 112a) of the first main body 111 (second main body 112). ing.

  As mentioned above, although embodiment and the modification of this invention were demonstrated, the construction method of the tunnel which concerns on this invention is not restricted to these, These can be combined as much as possible.

DESCRIPTION OF SYMBOLS 1 ... Tunnel support structure 2 ... Anchor anchor 3 ... Primary shot concrete layer 6 ... Secondary shot concrete layer 7 ... Ground 8 ... Face 10 ... Tunnel support work 10L ... left steel support 10R ... right steel support 40 ... female mold connection 41 ... casing 42 ... storage chamber 46 ... female locking member 48 ... Insertion port 50 ... male connecting part 51 ... male locking member 111 ... first body part 112 ... second body part 121 ... first top end joint plate 122 ... first 2 Top end joint plate

Claims (11)

An erector arrangement step of arranging a heavy machine on which the erector apparatus having a pair of hands capable of gripping a pair of steel support members divided in an arc shape on the face of the tunnel;
A support connection step of connecting the pair of steel support to each other at the top ends by driving the hand while holding the pair of steel support to each of the pair of hands;
By driving the pair of hands, an arch-shaped steel support structure in which the top ends are connected to each other at a predetermined erection position;
Have
The connecting structure for connecting the pair of steel support members to each other at the top ends is as follows.
A first top end joint plate and a second top end joint plate, which are respectively provided at the top end portions of the pair of steel support members and are brought into contact with each other when the pair of steel support members are connected;
A female connecting portion recessed in the first top end joint plate;
A male connecting portion projecting from the second top end joint plate;
With
The male connecting portion has a rod-shaped male locking member protruding from the second top joint plate,
The female connecting portion has an opening hole formed through the first top joint plate, and a storage chamber in which an insertion port communicating with the opening hole and allowing insertion of the male locking member is formed. includes a casing having therein to lock the male locking member inserted into the storage chamber from the insertion opening,
In the support connection step, the second top joint plate is guided by a guide member provided on an outer peripheral edge of the first top joint plate, and the male die is locked to the insertion port of the female joint portion. Lead the material,
The guide member is provided only on two sides forming a corner at an outer peripheral edge of the first top joint plate, and an upper guide wall provided on an upper edge of the first top joint plate; Of the first top joint plate, it has a side guide wall provided on the side edge facing the face at the time of connection of the pair of steel support works,
How to build a tunnel. The tunnel construction method according to claim 1, wherein a width dimension of the upper guide wall is smaller than a length of the upper edge of the first top end joint plate. The tunnel construction method according to claim 1 or 2, wherein a width dimension of the side guide wall is smaller than a length of the side edge of the first top end joint plate. An erector arrangement step of arranging a heavy machine on which the erector apparatus having a pair of hands capable of gripping a pair of steel support members divided in an arc shape on the face of the tunnel;
A support connection step of connecting the pair of steel support to each other at the top ends by driving the hand while holding the pair of steel support to each of the pair of hands;
By driving the pair of hands, an arch-shaped steel support structure in which the top ends are connected to each other at a predetermined erection position;
Have
The connecting structure for connecting the pair of steel support members to each other at the top ends is as follows.
A first top end joint plate and a second top end joint plate, which are respectively provided at the top end portions of the pair of steel support members and are brought into contact with each other when the pair of steel support members are connected;
A female connecting portion recessed in the first top end joint plate;
A male connecting portion projecting from the second top end joint plate;
With
The male connecting portion has a rod-shaped male locking member protruding from the second top joint plate,
The female connecting portion has an opening hole formed through the first top joint plate, and a storage chamber in which an insertion port communicating with the opening hole and allowing insertion of the male locking member is formed. includes a casing having therein to lock the male locking member inserted into the storage chamber from the insertion opening,
The first top end joint plate has a concave shape, and the second top end joint plate has a convex shape complementary to the concave shape of the first top end joint plate. When the pair of steel support members are connected, the first top end joint plate and the second top end joint plate are formed in surface contact with each other,
In the support connection step, the male locking member is guided by sliding along the concave surface of the first top joint plate, and the male locking member is inserted into the insertion port of the female connection portion. Leading to
How to build a tunnel. The female connecting portion is disposed in the most recessed region in the region of the first top joint plate having the concave shape,
The male locking member is disposed in the most raised region in the region of the second top joint plate having the convex shape.
The tunnel construction method according to claim 4 . The female connecting portion is formed in the storage chamber and has a tapered hole having a diameter reduced toward the insertion port, and is divided into a plurality of portions in the circumferential direction in the tapered hole and is formed on the tapered surface. along with the female engaging member slidably disposed wedge by a plurality juxtaposed circumferential direction of the female side locking groove on the inner surface of the female locking member, said female engagement member and the A pressing member that presses toward the insertion port side ,
The male connector further includes a plurality of circumferential male locking grooves arranged in parallel on the outer periphery of the male locking member,
When the male locking member is inserted from the insertion port of the female connecting portion, the male locking member resists the pressing force of the pressing member and causes the female locking member to taper. The male locking member is inserted into the storage chamber while expanding the inner surface of the female locking member by retreating along the surface,
When the insertion of the male locking member into the storage chamber is completed, the female locking member is pushed back toward the insertion port along the tapered surface by the pressing force of the pressing member. The inner surface of the female locking member is reduced in diameter, and the female locking groove and the male locking groove are engaged with each other, so that the male connection portion and the female connection portion are integrally connected. To be
The tunnel construction method according to any one of claims 1 to 5 . The heavy machinery is further equipped with a spraying device for shotcrete,
In a state where the arch-shaped steel supporter installed at the built-in position is gripped by the pair of hands, the sprayed concrete is sprayed onto the legs of the steel supporter by the spraying device. A temporary fixing step of temporarily fixing the support work to the tunnel pit wall;
After the temporary fixing step, a grip releasing step for releasing the holding of the steel support by the pair of hands,
Spray concrete is sprayed between the steel support temporarily fixed to the tunnel pit wall and the existing steel support adjacent to the steel support in the axial direction of the tunnel, and the steel support is newly installed. A spraying process in which the entire longitudinal direction of the work is embedded in shotcrete,
The tunnel construction method according to any one of claims 1 to 6 , further comprising: The steel support has an H-shaped cross section, and an anchor member fixed to the shotcrete on the web of the leg is projected.
In the temporary fixing step, the anchor member is buried in the shotcrete,
The tunnel construction method according to claim 7 . The tunnel construction method according to claim 8 , wherein the anchor member is protruded on both surfaces of the web. The opening hole has a tapered surface that expands from the inner surface side to the outer surface side in the thickness direction of the first top joint plate,
In the support connection step, the male locking member is guided by sliding along the tapered surface of the opening hole of the first top joint plate, and is inserted into the insertion port of the female connection portion. Guiding the male locking member;
The tunnel construction method according to any one of claims 1 to 9 . A tapered surface that decreases in diameter toward the tip is formed at the tip of the male locking member,
In the support connection step, the taper surface of the male locking member is guided by sliding along the edge of the opening hole of the first top joint plate, and the female connection portion is guided. Leading the male locking member to the insertion opening;
The tunnel construction method according to any one of claims 1 to 10 .

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