JP2013072200A - Adit construction method and departure method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adit construction method with which a space can be secured at the back of a follower.SOLUTION: According to an adit construction method utilizing a departure facility D provided within an existing tunnel A, a follower 5 abutted to a rear end face of a following box 2 is disposed at the back of a departure port and after a connection material 8 from an opening edge of the departure port to the follower 5 is disposed, a tensile force is applied to the connection material 8 by a jack 6 which is mounted to the follower 5, thereby moving the follower 5 to the side of the departure. Therefore, a leading box 1 and the following box 2 are extruded from the departure port.

Description

  The present invention relates to a horizontal pit construction method and a starting facility for a propulsion method.

  The propulsion method is a method of constructing a horizontal shaft in the ground by extruding a box placed at the starting port with a main jack, and a horizontal shaft extending from a vertical shaft (see Patent Document 1) or existing parallel tunnels. It is used when constructing connecting horizontal shafts (see Patent Document 2).

JP 2007-138523 A (FIG. 3) Japanese Patent Laid-Open No. 11-148296

  In the propulsion method, a reaction force stand (reaction force receiver of the main push jack) is built behind the pusher wheel that contacts the rear end surface of the box, and the structure located on the opposite side of the starting port (the box is pushed out from the shaft. In this case, it is necessary to fix the reaction force frame to the side wall of the shaft or the tunnel lining when the box is pushed out from the existing tunnel. Therefore, the space behind the push ring is blocked by the reaction force frame. In particular, when a starting port is provided in an existing tunnel, the work path in the existing tunnel is blocked by the reaction force frame, making it difficult to travel in the longitudinal direction of the existing tunnel. May cause trouble.

  From such a viewpoint, an object of the present invention is to provide a horizontal shaft construction method and a starting facility capable of securing a space behind a push wheel.

  The horizontal shaft construction method according to the present invention that solves the above-described problem is that a push ring that contacts the rear end face of the box is arranged behind the start opening, and a connecting material that extends from the opening edge of the start opening to the push ring is arranged. After that, the box is pushed out from the starting port by applying a tensile force to the connecting member with a jack attached to the pressing wheel and moving the pressing wheel to the starting port side. In the present invention, “front” and “rear” are based on the box propulsion direction.

  According to the present invention, the reaction force (tensile force applied to the connecting material) during the box propulsion acts on the opening edge of the start opening (the part surrounding the start opening). There is no need to construct a large scale reaction force frame, and therefore it is possible to secure a space behind the pusher wheel. The box body propulsion may be carried out by applying reaction force only to the opening edge of the launch opening, but a small reaction force stand that does not block the space behind the wheel is constructed behind the wheel, You may help.

  In addition, the shape of a box can select freely circular, a rectangle, an ellipse, a horseshoe shape, etc. according to the use of a horizontal shaft.

  A starting facility according to the present invention that solves the above-mentioned problems is a starting facility for a propulsion method used when pushing out a box from a starting port, and is attached to the pressing wheel that contacts the rear end surface of the box. And a connecting member that extends from the opening edge of the start opening to the push ring, and the press wheel moves to the start opening side when a tensile force is applied to the connecting member with the jack. It is characterized by.

  If the starting equipment according to the present invention is used, the reaction force during box propulsion acts on the opening edge of the starting port, so there is no need to construct a large reaction force stand behind the pusher wheel. Therefore, it is possible to secure a space behind the push wheel. In addition, a small reaction force stand that does not block the space behind the pusher wheel may be constructed behind the pusher wheel to assist the box propulsion.

  In addition, another starting equipment according to the present invention that solves the above problems is a starting equipment for a propulsion method that is used when the box is pushed out from a starting port provided in an existing tunnel, and the rear end face of the box A push ring abutting on the push ring, a jack attached to the push ring, a bracket disposed at an opening edge of the start opening, and a connecting member extending from the bracket to the push ring. It is fixed to the lining, and when the tensile force is applied to the connecting member with the jack, the push wheel moves to the start opening side.

  If the starting equipment according to the present invention is used, the reaction force during the box propulsion acts on the lining around the starting opening, so there is no need to construct a large reaction force stand behind the pusher wheel. Therefore, it is possible to secure a space behind the push wheel. In other words, it is possible to secure a working path for the existing tunnel even behind the wheel, and therefore, it is possible to perform an underground work on the existing tunnel in parallel with the construction work of the horizontal shaft. Note that a small reaction force stand that does not block the work path may be constructed behind the pusher wheel to assist the box propulsion.

  According to the present invention, it is possible to secure a space behind the push wheel.

It is sectional drawing which shows the horizontal shaft construction method and start equipment which concern on embodiment of this invention. It is an expanded vertical sectional view which shows the head part of a horizontal shaft. It is a perspective view which shows a top box, a subsequent box, a retrofitting lining, and a connection frame. It is a front view of a top box. (A) is the X1-X1 sectional view taken on the line of FIG. 4, (b) is the X2-X2 sectional view taken on the line of (a). It is a disassembled perspective view of a top box. It is a front view of a retrofit lining body. (A) is the X3-X3 sectional view taken on the line of FIG. 7, (b) is the X4-X4 sectional view taken on the line of FIG. It is a disassembled perspective view of a retrofit lining body. It is a side view showing starting facilities concerning an embodiment of the present invention. It is a rear view which shows the starting installation which concerns on embodiment of this invention. It is a perspective view which shows the bracket of start equipment. (A) is sectional drawing of a bracket, (b) is sectional drawing which shows the edge part of a connection material. (A) is a longitudinal cross-sectional view which shows the condition which brought the head box close to the arrival side underground structure, and (b) is a longitudinal cross-sectional view which shows a retrofit process. (A) is a longitudinal cross-sectional view which shows a temporary water stop process, (b) is a longitudinal cross-sectional view which shows a connection frame arrangement | positioning process.

  As shown in FIG. 1, the horizontal shaft construction method according to the embodiment of the present invention is reached from the existing tunnel A on the starting side using the starting equipment D (the push wheel 5, the jack 6, the bracket 7 and the connecting member 8). The side pit C leading to the existing tunnel B on the side is constructed.

<Existing tunnel>
The existing tunnels A and B are constructed by a shield method, and are arranged in parallel at intervals.

  One of the existing tunnels A has a departure opening. Of the lining (outer shell) of the existing tunnel A, at least the part serving as the starting port is a steel segment. In order to prevent harmful deformation of the existing tunnel A when the lining is cut open, a reinforcing steel material or the like is disposed on the steel segment disposed at the opening edge of the start opening (the part surrounding the start opening).

  In the other existing tunnel B, an arrival port is formed. Of the lining (outer shell) of the existing tunnel B, at least the part that becomes the arrival port is a steel segment.

<Horizontal shaft>
The horizontal pit C is a connecting mine (tunnel) connecting the existing tunnels A and B. As shown in FIG. 2, the horizontal pit main body (box 1, 2), a retrofit lining body 3 retrofitted to the horizontal shaft main body, and a connection frame 4 arranged at the arrival port. In addition, although the cross-sectional shape of the horizontal pit C is a rectangle, other shapes (for example, circular shape, an ellipse shape, a horseshoe shape, etc.) may be sufficient.

  The horizontal shaft main body is composed of a plurality of boxes 1, 2, 2,... Connected in the longitudinal direction of the horizontal shaft C. In the following, among the plurality of boxes 1, 2, 2,..., The box 1 that is first pushed out from the starting port is referred to as “head box 1”, and the other boxes (behind the head box 1). Box 2) connected to is referred to as “succeeding box 2”.

  As shown in FIG. 3, the top box 1 is a rectangular tube-shaped covering body, and includes a bottom printing plate, a pair of left and right side walls rising from both ends thereof, and a top plate horizontally mounted between the left and right side walls. Department. More specifically, the leading box 1 is made of steel, and a plurality of rows (in this embodiment, two rows) of main girder frames 11 and 11 and a plurality of juxtaposed between the main girder frames 11 and 11. .., The outer skin plate 13 disposed along the outer peripheral edge of the main girder frame 11, 11, and the inner surface plate 14 projecting forward from the inner peripheral edge of the main girder frame 11 in the front row. And a plurality of reinforcing ribs 15, 15,... Arranged in parallel between the outer skin plate 13 and the inner surface plate 14.

  The main girder frames 11 and 11 are arranged in parallel with a space in the box propelling direction (front-rear direction). Each main girder frame 11 has a rectangular frame shape in front view. A plurality of bolt insertion holes (not shown) are formed in the main girder frame 11. A bolt (not shown) for joining the adjacent succeeding box 2 or retrofitting lining body 3 to the leading box 1 is inserted into the bolt insertion hole.

  The vertical ribs 12, 12,... Are juxtaposed at intervals in the box circumferential direction (left-right direction or up-down direction). Each vertical rib 12 transmits box driving force and is arranged in a direction intersecting with the main girder frames 11 and 11. The vertical ribs 12 are welded to the main girder frame 11 and the outer skin plate 13.

  The outer skin plate 13 is welded to the main girder frame 11 and the vertical ribs 12. The outer skin plate 13 has a cylindrical shape when viewed from the front, but the upper half of the outer skin plate 13 protrudes forward from the main girder frame 11 in the front row. The overhanging portion 13a of the outer skin plate 13 (the portion overhanging from the main girder frame 11 in the foremost row) has an inverted U shape when viewed from the front, and functions as a landslide prevention hood during excavation of natural ground.

  As shown in FIG. 4, the inner surface plate 14 is disposed on the inner side of the outer skin plate 13 and faces the protruding portion 13 a with a gap. The inner surface plate 14 of this embodiment is arrange | positioned at the upper part of the top box 1, and is exhibiting reverse U character shape in front view. As shown in FIG. 5A, the inner surface plate 14 projects from the front surface of the frontmost main girder frame 11 toward the front (opening edge of the arrival port). The overhang length of the inner surface plate 14 is smaller than the maximum overhang length of the overhang portion 13a. As shown in FIG. 5B, the connection frame 4 is fixed to the inner peripheral surface of the inner surface plate 14. The inner surface plate 14 is offset from the inner peripheral edge of the main girder frame 11 to the outer skin plate 13 side by the thickness of the connection frame 4.

  As shown in FIG. 4, the reinforcing ribs 15, 15,... Are arranged side by side in the box circumferential direction (left-right direction or up-down direction), and support the inner surface plate 14 from the outside (natural ground side). ing. Each reinforcing rib 15 is arranged in a direction intersecting with the outer skin plate 13 and the inner surface plate 14, and is welded to the main girder frame 11, the outer skin plate 13 and the inner surface plate 14 in the foremost row.

  As shown in FIG. 6, the leading box 1 is composed of a plurality of steel pieces (steel segments). There are no restrictions on the number of divisions and the shape of each piece.

  The leading box 1 of the present embodiment includes an I-shaped (straight-line) lower piece 1a, L-shaped side pieces 1b and 1b arranged on the left and right sides of the lower piece 1a, and side pieces 1b and 1b. It is composed of an inverted U-shaped (U-shaped) upper piece 1c installed between them. That is, the top box 1 of the present embodiment is divided into four pieces.

  The lower piece 1 a is a horizontally-long rectangular parallelepiped piece that constitutes the central portion of the bottom plate portion of the leading box 1.

  The side piece 1b is a piece that constitutes a part of the bottom plate portion and the side wall portion of the leading box 1, and rises from the bottom plate constituting portion that is bolted to the side end surface of the lower piece 1a and the end portion of the bottom plate constituting portion. A side wall component.

  The upper piece 1c is a piece that constitutes a part of the side wall portion and the top plate portion of the leading box 1, and a pair of left and right side wall components that are bolted to the upper end surfaces of the side pieces 1b and 1b, And a top plate component that is horizontally mounted on the side wall component.

  In addition, the overhang | projection part 13a (sediment collapse prevention hood) of the outer skin plate 13 is formed in the upper half part and upper piece 1c of the side piece 1b, and the inner surface plate 14 and the reinforcing ribs 15, 15,. It is arranged only in the upper piece 1c. In addition, the lower edge of the inner surface plate 14 and the lowermost reinforcing rib 15 are positioned higher than the lower end surface of the upper piece 1c (the surface abutted against the upper end surface of the side piece 1b).

  As shown in FIG. 3, the trailing box 2 is a rectangular tube-shaped covering body, and includes a bottom plate portion, a pair of left and right side wall portions rising from both ends thereof, and a top plate horizontally mounted between the left and right side wall portions. Department. More specifically, the succeeding box 2 is made of steel, and is arranged in parallel between a plurality of rows (four in this embodiment) of main girder frames 21, 21,... And adjacent main girder frames 21, 21. Are provided with a plurality of vertical ribs 22, 22,... And a skin plate 23 surrounding the main girder frames 21, 21 from the outside.

  The main girder frames 21, 21,... Are juxtaposed in the box propelling direction (vertical direction of the horizontal pit C). Each main girder frame 21 has a rectangular frame shape in front view. A plurality of bolt insertion holes (not shown) are formed in the main girder frame 21. Bolts (not shown) for joining the subsequent box 2 to another adjacent box (first box 1 or other subsequent box 2) are inserted into the bolt insertion holes.

The vertical ribs 22, 22,... Are arranged side by side in the box circumferential direction (left-right direction or up-down direction) with an interval. Each vertical rib 22 transmits box driving force, and is substantially perpendicular to the main girder frames 21 and 21.
The skin plate 23 has a cylindrical shape when viewed from the front, and is welded to the main girder frame 21 and the vertical ribs 22.

  The succeeding box 2 is composed of a plurality of steel pieces (steel segments). Although there is no restriction | limiting in the number of division | segmentation, the shape of each piece, etc. In this embodiment, the 2 types of L-shaped pieces 2a and 2b are combined 2 each, and the succeeding box 2 is formed. That is, the succeeding box 2 is divided into four pieces.

  The retrofitting lining body 3 is a U-shaped lining body in front view, and includes a bottom plate portion and a pair of left and right side wall portions that rise from both ends thereof. The front edge of the side wall portion of the retrofit lining body 3 is formed into a curve (in the present embodiment, an arc) along the outline of the lining of the existing tunnel B. That is, the retrofit lining body 3 is formed in a shape along the outer surface shape of the lining of the existing tunnel B.

  The post lining 3 is made of steel, and as shown in FIG. 7, a joint plate 31 having a U-shape in front view, and female screw members 32, 32,... Attached to the front surface of the joint plate 31, A plurality of reinforcing ribs 33, 33,... Arranged side by side on the front surface side of the joint plate 31 and an inner skin plate 34 protruding from the joint plate 31 toward the front (opening edge of the arrival port).

  As shown in FIG. 8A, the joint plate 31 is a portion that is overlapped with the main girder frame 11 in the foremost row of the leading box 1. A plurality of bolt insertion holes (not shown) are formed in the joint plate 31. Bolts for joining the retrofit lining body 3 to the leading box 1 are inserted into the bolt insertion holes.

  The female screw member 32 is disposed corresponding to a bolt insertion hole (not shown) of the joint plate 31. The internal thread member 32 of this embodiment consists of a high nut, and is fixed to the front surface of the joint plate 31 by welding.

  As shown in FIG. 7, the reinforcing ribs 33, 33,... Support the inner skin plate 34 from the outside (natural ground side), and are arranged in parallel in the box circumferential direction. As shown in FIG. 8A, each reinforcing rib 33 protrudes forward from the front surface of the joint plate 31 and is welded to the front surface of the joint plate 31 and the outer surface of the inner skin plate 34.

  As shown in FIG. 7, the inner skin plate 34 is arranged along the inner peripheral edge of the joint plate 31. The upper end of the inner skin plate 34 is connected to the inner surface plate 14 of the leading box 1, and the boundary portion between the inner surface plate 14 and the inner skin plate 34 is flush. As shown to (a) of FIG. 8, the front edge of the inner skin plate 34 in the side wall part of the retrofit lining body 3 is shape | molded by the circular arc which follows the outline of the lining (outer shell) of the existing tunnel B. As shown in FIG. As shown in FIG. 8B, the main girder frame 11 is offset from the inner periphery of the main girder frame 11 to the outside (natural ground side) by the thickness of the connection frame 4. The connection frame 4 is fixed to the inner peripheral surface of the inner skin plate 34.

  As shown in FIG. 9, the retrofit lining body 3 is composed of a plurality of steel pieces (steel segments). Although there is no restriction | limiting in the number of division | segmentation, the shape of each piece, etc., the back lining body 3 of this embodiment is L arrange | positioned at the right-and-left both sides of the I-type (straight type) lower joint piece 3a and the lower joint piece 3a. It consists of character-shaped side joint pieces 3b and 3b. That is, the retrofit body 3 is divided into three pieces, and each piece is formed in a size that can be carried through the internal space of the horizontal shaft main body.

  The lower joint piece 3 a is a piece that constitutes the central portion of the bottom plate portion of the retrofitted body 3. The width dimension (length dimension in the box propulsion direction) of the lower joint piece 3a is uniform. The lower joint piece 3a has an inverted trapezoidal shape when viewed from the front, and the reinforcing ribs 33 and 33 (both end surfaces of the lower joint piece 3a) located at both ends thereof are arranged in an inverted C shape. . The lower joint piece 3a is disposed in front of the lower piece 1a (see FIG. 6) of the leading box 1 and is bolted to the front surface of the lower piece 1a. A bolt (not shown) is inserted from the lower piece 1 a side and screwed into the female screw member 32.

  The side joint piece 3b is a piece that constitutes a part of the bottom plate portion and the side wall portion of the retrofitted post-reconstructed body 3, and includes a bottom plate constituting portion that is abutted against a side end surface of the lower joint piece 3a, and an end portion of the bottom plate constituting portion. And a side wall component that rises. The width dimension (length dimension in the box propelling direction) of the side joint piece 3b increases or decreases in accordance with the outer surface shape of the lining of the existing tunnel B. The upper end surface of the side joint piece 3b (the reinforcing rib 33 positioned at the top of the reinforcing ribs 33, 33,... Arranged in the side wall constituting portion) is the lowermost reinforcing rib 15 of the leading box 1 (see FIG. 6). Further, the side end face of the side joint piece 3b is inclined corresponding to the side end face of the lower joint piece 3a, and is abutted against the reinforcing rib 33 at the side end of the lower joint piece 3a.

  As shown in FIG. 3, the connection frame 4 has a rectangular frame shape when viewed from the front. The front edges of the upper and lower sides of the connection frame 4 form a straight line that is substantially parallel to the vertical alignment of the existing tunnel B, and the front edges of the left and right side parts of the connection frame 4 cover the existing tunnel B. An arc is formed along the contour of the work. The connection frame 4 is carried in a state of being divided into a plurality of connection plates (band-shaped steel plates), and is assembled into a frame shape at the arrival port. The connection plates are joined by welding.

  As shown in FIG. 2, the front end of the connection frame 4 is fixed to the opening edge of the arrival port (the lining of the existing tunnel B) by welding. The weld bead is continuously formed over the entire length of the front end edge of the connection frame 4 so that groundwater does not flow from between the connection frame 4 and the opening edge.

  The rear end portion of the connection frame 4 is fixed to the inner surface of the leading box 1 and the inner surface of the post-covering wrapping body 3 (that is, an endless surface formed in the front region of the main girder frame 11 in the front row) by welding. Has been. That is, as shown in FIG. 5B, the portion along the inner surface plate 14 of the rear end portion of the connection frame 4 is fixed to the inner surface plate 14, and as shown in FIG. 8B. The portion along the inner skin plate 34 is fixed to the inner skin plate 34. The weld bead is continuously formed over the entire length of the rear edge of the connection frame 4 so that groundwater does not flow between the connection frame 4 and the leading box 1 or between the connection frame 4 and the retrofitting 3. To do.

<Starting equipment>
The starting facility D shown in FIG. 1 is a facility for pressing the succeeding box 2 connected after the leading box 1 toward the arrival port, and is built in the existing tunnel A that is a starting side underground structure. ing.

  As shown in FIG. 10, the starting equipment D includes a pusher wheel 5 that comes into contact with the rear end surface of the succeeding box 2, a jack 6 attached to the pusher wheel 5, a bracket 7 disposed at an opening edge of the starting opening, A connecting member 8 extending from the bracket 7 to the press wheel 5 and a guide rail 9 extending from the lower side of the press wheel 5 toward the start opening are provided.

  As shown in FIG. 11, the presser wheel 5 includes a pair of upper and lower transverse members 51, 51, a pair of left and right longitudinal members 52, 52, a protruding member 53 projecting from the longitudinal member 52 toward the side, and a longitudinal member. 52, and a pair of left and right carts 55, 55 projecting rearward from the lower cross member 51.

  The cross member 51 is made of steel. The end of the cross member 51 protrudes to the side of the vertical member 52. As shown in FIG. 10, the lower cross member 51 contacts the rear end surface of the lower portion of the subsequent box 2, and the upper cross member 51 contacts the rear end surface of the upper portion of the subsequent box 2.

  The vertical member 52 contacts the rear end surface of the side wall portion of the subsequent box 2. The vertical member 52 is made of steel and joined to the horizontal members 51 and 51.

  The overhanging material 53 is a member that supports an intermediate portion in the height direction of the receiving material 54, and protrudes laterally from the intermediate portion in the height direction of the vertical material 52.

  The receiving material 54 is a member serving as a mounting base for the jack 6, and extends in the vertical direction (direction along the vertical material 52). The cradle 54 is disposed on the rear side of the cross members 51, 51 and the overhang material 53, and is joined to the rear surface of the cross members 51, 51 and the rear surface of the overhang material 53. As shown in FIG. 11, the receiving member 54 is composed of a pair of steel materials 54a, 54a and a plurality of reinforcing plates 54b, 54b,... Connecting the steel materials 54a, 54a. The steel materials 54a and 54a are arranged side by side with a gap (connection material insertion space) for inserting the connection material 8 therebetween.

  As shown in FIG. 10, the carriage 55 is disposed immediately above the guide rail 9. Wheels that roll on the upper surface of the guide rail 9 are attached to the carriage 55.

  The jack 6 is a center hole jack and is attached to the rear surface of the receiving material 54. The hole (insertion hole) of the center hole jack is opened in the connecting material insertion space of the receiving material 54 (between the steel materials 54a and 54a shown in FIG. 11). In the present embodiment, two upper and lower jacks 6 and 6 are arranged for one receiving material 54, but the number of jacks 6 and the like may be appropriately changed.

  The bracket 7 is fixed to the lining of the existing tunnel A (the steel segment 10 in this embodiment). As shown in FIG. 12, the steel segment 10 includes main girders 10a, 10a arranged in parallel in the longitudinal direction of the existing tunnel A, and a plurality of vertical ribs arranged in parallel between the main girders 10a, 10a. 10b, 10b,... And a skin plate 10c disposed on the outer peripheral side of the main girders 10a, 10a. As shown in FIG. 13A, the vertical rib 10 b includes a plate portion 101 erected on the inner peripheral surface of the skin plate 10 c and a stiffening portion 102 formed at an end portion of the plate portion 101. And has a T-shaped cross section. A bolt insertion hole (not shown) is formed in the plate portion 101. The stiffening portion 102 has a strip shape parallel to the skin plate 10 c and extends in the longitudinal direction of the existing tunnel A.

  As shown in FIG. 12, the bracket 7 is fixed to the longitudinal ribs 10b, 10b,... Adjacent in the circumferential direction of the existing tunnel A, and a plurality of (three in this embodiment) bases 7a, 7a, And a beam 7b installed on the bases 7a, 7a,.

  As shown in FIG. 13A, the base 7a includes a mounting plate portion 71 that is superimposed on the stiffening portion 102 of the vertical rib 10b, and a pair of sandwiching portions 72 and 72 that face each other with the stiffening portion 102 interposed therebetween. Cylindrical spacers 73, 73 disposed between the sandwiching portions 72, 72, and reinforcing plate portions 74, 74,... That reinforce the mounting plate portion 71 are provided. The base 7a is bolted to the vertical rib 10b by a base fixing bolt 75.

  The mounting plate portion 71 is disposed so as to straddle the stiffening portion 102. Both end portions of the mounting plate portion 71 project from the stiffening portion 102. A bolt insertion hole (not shown) is formed at an end portion of the mounting plate portion 71 (a portion protruding from the stiffening portion 102).

  The sandwiching portion 72 is erected on the back surface (surface on the skin plate 10 c side) of the mounting plate portion 71 and faces the plate portion 101. Bolt insertion holes (not shown) are formed in the clamping portion 72.

  The cylindrical spacer 73 is disposed between the sandwiching portion 72 and the plate portion 101. The hollow part of the cylindrical spacer 73 communicates with the bolt insertion hole of the clamping part 72 and the bolt insertion hole of the plate part 101.

  The reinforcing plate portion 74 is disposed at an end portion (a portion protruding from the stiffening portion 102) of the mounting plate portion 71 and is fixed to the mounting plate portion 71 and the sandwiching portion 72.

  The base fixing bolt 75 includes a shaft portion penetrating the clamping portions 72 and 72. The shaft portion of the base fixing bolt 75 is a through-hole from one clamping portion 72 to the other clamping portion 72 (the bolt insertion hole of the clamping portion 72, the hollow portion of the cylindrical spacer 73, the bolt insertion hole of the plate portion 101). Is inserted from one clamping portion 72 side. A nut is fastened to the shaft portion of the base fixing bolt 75 protruding from the other holding portion 72.

  The beam 7 b includes a flange 76 that is superimposed on the mounting plate portion 71 of the base 7 a, a web 77 that is erected on the flange 76, and a plurality of ribs 78, 78,. . The beam 7 b is bolted to the base 7 a by a beam fixing bolt 79.

  Bolt insertion holes (not shown) corresponding to the bolt insertion holes of the mounting plate portion 71 are formed in the flange 76.

  The web 77 is erected on the surface of the flange 76. The web 77 has a plurality of pin insertion holes 77a, 77a,. The pin insertion holes 77a, 77a,... Are arranged at intervals in the longitudinal direction of the web 77 (the circumferential direction of the existing tunnel A).

  The rib 78 prevents the web 77 from collapsing and disperses the tensile force transmitted from the web 77 to the flange 76 in the width direction of the flange 76, and is arranged in a direction intersecting the web 77. The ribs 78 are disposed on both sides of the web 77 and are welded to the surface of the flange 76 and the side of the web 77.

  The beam fixing bolt 79 includes a shaft portion penetrating the mounting plate portion 71 and the flange 76. The shaft portion of the beam fixing bolt 79 is inserted into the mounting plate portion 71 and the bolt insertion hole of the flange 76 from the back side of the mounting plate portion 71. A nut is fastened to the shaft portion of the beam fixing bolt 79 protruding from the surface of the flange 76.

  As shown in FIG. 13B, the connecting member 8 includes a linear member 8a and a coupler 8b attached to the front end portion (end portion on the bracket 7 side) of the linear member 8a.

  The linear member 8a is made of a PC steel rod. The rear end side of the linear member 8a is inserted through the hole of the jack 6 (see FIG. 10).

  The coupler 8b includes a base portion 81 having a plate shape, a female screw member 82 disposed on the back surface of the base portion 81, a pair of facing portions 83 and 83 facing each other with the female screw member 82 interposed therebetween, and the facing portions 83 and 83. And a pin 84 penetrating therethrough.

  An insertion hole (not shown) for the linear member 8a is formed in the base 81. The female screw hole of the female screw member 82 communicates with the insertion hole of the base portion 81. A linear member 8 a is screwed to the female screw member 82.

  The facing portions 83 and 83 extend from the base portion 81 toward the bracket 7. The front end portions of the facing portions 83, 83 are located in front of the front end of the linear member 8 a and face each other with the web 77 of the bracket 7 interposed therebetween. A pin insertion hole (not shown) is formed in the front end portion of the facing portion 83.

  The pin 84 is inserted into the pin insertion holes of the facing portions 83 and 83 and is inserted into the pin insertion hole 77a (see FIG. 13A) of the web 77. The tensile force applied to the linear member 8 a acts on the bracket 7 via the pin 84.

<Horizontal pit construction method>
The horizontal shaft construction method according to the present embodiment includes a start preparation step, an excavation propulsion step, a retrofit step, a temporary water stop step, an arrival port formation step, and a connection frame arrangement step. In addition, in this embodiment, although the ground improvement by the chemical | medical solution injection | pouring is carried out from the existing tunnels A and B with respect to the area | region including the construction planned position of the horizontal pit C, ground improvement is abbreviate | omitted according to the condition of a natural ground. May be.

  As shown in FIG. 10, the start preparation step is a step of constructing a start facility D and preparing a leading box 1 and a subsequent box 2 having a predetermined number of rings (1 ring in the present embodiment).

  In the start preparation step, first, a rectangular frame-shaped entrance frame (not shown) is installed on the lining of the existing tunnel A, and the lining on the outside of the entrance frame (that is, the lining that becomes the opening edge of the start opening). Brackets 7, 7,. In addition, a guide rail 9 is laid on the work gantry in the existing tunnel A.

  Next, a plurality of pieces (lower piece 1a, side pieces 1b and 1b, upper piece 1c shown in FIG. 3) and a plurality of pieces (L shown in FIG. The character-shaped pieces 2 a and 2 b) are carried in, and the leading box 1 and the trailing box 2 are assembled on the guide rail 9. The leading box 1 and the subsequent box 2 may be assembled at the same time, or one of them may be assembled in advance.

  Subsequently, the pusher wheel 5 is arranged behind the succeeding box 2, and the connecting members 8, 8,... Are arranged on both sides of the leading box 1 and the succeeding box 2. The connecting member 8 (linear member 8 a) is inserted into the hole of the jack 6, and the front end (coupler 8 b) of the connecting member 8 is connected to the bracket 7.

  Thereafter, the lining of the existing tunnel A is cut along the inner periphery of the entrance frame (not shown) to form a start opening. In addition, the entrance packing which contacts the outer peripheral surface of the leading box 1 or the trailing box 2 is attached to the entrance frame. Once the launch opening is formed, the process proceeds to the excavation propulsion process.

  The excavation promotion process is a process of repeating excavation work of natural ground, advance work of the leading box 1 and the subsequent box 2, and additional assembly work of the subsequent box 2 (see FIG. 1).

  In the excavation propulsion process, first, a natural ground exposed at the starting point is excavated. When the natural ground is excavated, the jack 6 is operated to draw the linear member 8a of the connecting member 8 to the rear of the jack 6, and a tensile force is applied to the connecting member 8. Thus, when the pull-in amount of the linear member 8a is increased and the pusher wheel 5 is moved to the start opening side while contacting the rear end face of the succeeding box 2, the leading box 1 is pushed out from the start opening. When only the top box 1 is disposed, the top box 1 is pushed out from the start port by moving the pusher wheel 5 toward the start port while abutting the pusher wheel 5 on the rear end surface of the top box 1.

  The excavation work of the natural ground and the forward work of the leading box 1 and the subsequent box 2 are repeated, and when the amount of advance reaches one ring of the succeeding box 2, the pusher wheel 5 is moved backward once to free space Assemble a new subsequent box 2. Thereafter, the excavation work of the natural ground, the forward work of the leading box 1 and the subsequent box 2, and the assembly work of a new succeeding box 2 are repeated.

  As shown in FIG. 14 (a), when the leading box 1 approaches the lining (outer shell) of the existing tunnel B and the outer surface of the existing tunnel B is exposed, the process proceeds to a retrofitting process and a temporary water stop process.

  As shown in FIG. 14B, the retrofitting step is a step of arranging the retrofitting cover body 3 between the leading box 1 and the cover (outer shell) of the existing tunnel B.

  In the retrofitting process, a plurality of pieces (the lower joint piece 3a and the side joint pieces 3b and 3b shown in FIG. 3) constituting the retrofitting lining body 3 are carried through the horizontal shaft main body, and the leading box 1 and the existing tunnel B The post-cover lining body 3 is assembled with the lining.

  In the retrofitting process of the present embodiment, first, as shown in FIG. 8, the side joint piece 3 b is carried in and placed on the front side of the side piece 1 b of the top box 1. When the joint plate 31 of the side joint piece 3b is superimposed on the main girder frame 11 of the leading box 1 and the upper end surface of the side joint piece 3b is butted against the lowermost reinforcing rib 15 of the leading box 1, the leading box The side joint piece 3b is fixed to the leading box 1 by bolt fastening from the body 1 side. Since the inner skin plate 34 is provided on the post-covering wrapping body 3, the hand screw does not turn on the back side, but the female screw member 32 is fixed to the joint plate 31 in advance, so that the bolt from the front box 1 side The retrofitting lining body 3 can be attached to the leading box 1 by the fastening operation. When the left and right side joint pieces 3b, 3b are fixed to the leading box 1, the side end face of one side joint piece 3b and the side end face of the other side joint piece 3b are opposed to each other in an inverted C shape. (See FIG. 9).

  Next, the lower joint piece 3a shown in FIG. 9 is carried in and placed on the front side of the lower piece 1a (see FIG. 3) of the leading box 10. The lower joint piece 3a is dropped between the bottom plate components of the side joint pieces 3b and 3b. When the side end face of the lower joint piece 3a is abutted against the side end face of the side joint piece 3b while the joint plate 31 of the lower joint piece 3a is overlaid on the main girder frame 11 of the front case 1, The lower joint piece 3a is fixed to the leading box 1 by bolt fastening. When the retrofit lining body 3 is attached to the leading box 1, the leading box 1 and the trailing boxes 2, 2,... Are promoted as necessary, and the retrofit lining body 3 is further added to the lining of the existing tunnel B. Move closer.

  The temporary water stop process is a process of forming a temporary water stop structure outside the existing tunnel B as shown in FIG. If the risk of water discharge is low (when the position of the access port is higher than the groundwater surface, or when sufficient stop water is injected into the ground around the access port), the temporary water stop process is omitted. May be.

  In the temporary water stop process, first, the outer reach frame B1 is fixed to the outer surface of the lining of the existing tunnel B. The inner peripheral surface of the outer reaching frame B1 is an inner peripheral surface of the inner surface plate 14 (see FIG. 3) and the inner skin plate 34 (that is, an endless surface formed in the front region of the main row frame 11 in the foremost row). To match. The outer reach frame B1 is divided into a plurality of steel materials (an angle steel in this embodiment). Each steel material carries in each steel material through a horizontal shaft main body. The outer reachable frame B1 is formed by sequentially welding steel materials from the inner side of the horizontal shaft main body to the outer surface of the lining of the existing tunnel B. The weld bead is continuously formed over the entire circumference of the outer reach frame B1. The installation work of the outer reaching frame B1 may be performed in parallel with the retrofitting process, or may be performed before or after the retrofitting process.

  Subsequently, the leading box 1 and the retrofitting lining body 3 are joined to the outer reaching frame B1, the gap between the inner surface plate 14 (see FIG. 3) and the outer reaching frame B1, and the inner skin plate 34 and the outer reaching frame B1. Close the gap. In this embodiment, the temporary water stop steel plate B2 is disposed on the outer peripheral side (natural ground side) of the outer reach frame B1, and the temporary water stop steel plate B2 is welded to the inner surface plate 14, the inner skin plate 34, and the outer reach frame B1. Thus, the leading box 1 and the retrofitting lining 3 are joined to the outer reaching frame B1. The temporary water stop steel plate B2 is disposed on the outer peripheral side of the outer reach frame B1 through the gap between the inner surface plate 14 and the outer reach frame B1 or the gap between the inner skin plate 34 and the outer reach frame B1, and the weld bead is It forms continuously over the full length of steel plate B2 for temporary stop water.

  When the retrofitting process and the temporary water stop process are completed, back-filling is performed on the back surface of the back cover 3 and the back surface of the outer reach frame B1. When the backing material is cured, the process proceeds to the arrival port forming step.

  As shown in FIG. 15B, the arrival port forming step is a step of cutting the lining of the existing tunnel B to form the arrival port. In the present embodiment, the lining of the existing tunnel B is cut along the inner peripheral surface of the inner surface plate 14 and the inner skin plate 34 (that is, the inner peripheral surface of the outer reachable frame B1) by work from the side of the horizontal shaft main body. The opening shape of the arrival port is a shape corresponding to the cross-sectional shape of the space surrounded by the inner surface plate 14 and the inner skin plate 34 and is smaller than the outer shape of the leading box 1. After the arrival port is formed, the inner arrival frame B3 is attached to the opening edge of the arrival port. The inner reach frame B3 is fixed to the inner surface of the lining (steel segment) of the existing tunnel B by welding. The inner peripheral surface of the inner reaching frame B3 is made to coincide with the inner peripheral surfaces of the inner surface plate 14 and the inner skin plate 34 (that is, the inner peripheral surface of the outer reaching frame B1). The inner reach frame B3 is made of a steel material (an angle steel in this embodiment). When the inner reach frame B3 is attached, the process proceeds to the connection frame arrangement process.

A connection frame arrangement | positioning process is a process of arrange | positioning the connection frame 4 in an arrival port. In the connection frame arrangement step, a plurality of connection plates (band-shaped steel plates) constituting the connection frame 4 are carried through the horizontal shaft main body and assembled into a frame shape at the arrival port. The front end of the connection frame 4 is fixed to the opening edge of the arrival port (the inner peripheral surface of the inner arrival frame B3) by welding. Further, a portion of the rear end portion of the connection frame 4 along the inner surface plate 14 is fixed to the inner peripheral surface of the inner surface plate 14 (see FIG. 5B) by welding, and a portion along the inner skin plate 34 is fixed. Then, it is fixed to the inner peripheral surface of the inner skin plate 34 by welding.
After that, when the starting equipment D is removed and secondary lining is performed as necessary, the side pit C is completed.

  As described above, if the horizontal pit C is used using the starting equipment D, the reaction force (tensile force applied to the connecting member 8) during the box propulsion acts on the opening edge of the starting port. Therefore, it is not necessary to construct a large-scale reaction force stand behind the push wheel 5, and therefore it is possible to secure a space behind the push wheel 5. That is, as shown in FIG. 1, it is possible to secure a work path for the existing tunnel A even behind the push wheel 5, and therefore, the pit work for the existing tunnel A is performed in parallel with the construction work of the horizontal pit C. It becomes possible.

  Moreover, according to the horizontal shaft construction method according to the present embodiment, the outer shell of the existing tunnel B is cut open after the leading box 1 is brought close to the outer shell (lining) of the existing tunnel B on the arrival side ( Even if there is a large construction error in the top box 1, it can be easily handled. Moreover, since the size (opening range) of the arrival port can be kept to a minimum, the risk of water discharge during construction is reduced.

  Furthermore, according to the horizontal shaft construction method according to the present embodiment, since the retrofitting lining body 3 is arranged between the leading box 1 and the existing tunnel B (see FIG. 14 and the like), the leading box 1 and The gap formed with the existing tunnel B can be reduced, and as a result, it is possible to reduce the risk of flooding and landslides in the arrival port forming process. In particular, in this embodiment, after fixing the outer reach frame B1 to the outside of the existing tunnel B, and fixing the leading box 1 and the retrofitting lining body 3 to the outer reach frame B1 via the temporary water stop steel plate B2, Since the arrival port is formed (see FIG. 15), the risk of water discharge in the arrival port formation step can be further reduced. That is, according to the horizontal shaft C according to the present embodiment, it is possible to reduce the risk of flooding and landslides during construction. In addition, in the horizontal shaft construction method according to the present embodiment, the top box 1 is pushed out without the back cover lining body 3, so the presence of the back cover lining body 3 contributes to the natural ground resistance during box body propulsion. There is no effect.

  Moreover, according to the horizontal shaft construction method according to the present embodiment, since the connection frame 4 is arranged at the arrival port, a gap formed between the leading box 1 and the opening edge of the arrival port or a retrofitting cover A gap formed between the work body 3 and the opening edge of the arrival port can be closed, so that reliable water stop after the completion of the side pit is possible.

  In the present embodiment, the case where the leading box 1 and the trailing box 2 are divided into a plurality of pieces is illustrated, but the size of the leading box 1 and the trailing box 2 is larger than the inner hollow section of the existing tunnel A. May be carried from the wellhead of the existing tunnel A as a single piece without being divided into a plurality of pieces.

  In the present embodiment, the case where the inner box 14 and the reinforcing rib 15 are provided in the front box 1 and the U-shaped post lining 3 in front view is retrofitted to the front box 1 is illustrated. The plate 14 and the reinforcing rib 15 may be omitted, and the post-cover lining 3 in a front view frame shape may be retrofitted to the top box 1.

  In this embodiment, the connecting member 8 is connected to the opening edge of the starting port via the bracket 7, but the bracket 7 is omitted and the connecting member 8 is directly connected to the opening edge (steel segment 10) of the starting port. May be.

  Moreover, in this embodiment, although the case where the start port was provided in one side of the existing tunnels A and B provided side by side and the arrival port was provided in the other was illustrated, the start side underground structure and the arrival side underground structure It is not intended to limit the type or structure form. Although illustration is omitted, as a matter of course, it is possible to form a starting port or a reaching port in another underground structure such as a shaft.

A Existing tunnel B Existing tunnel (Ground structure on the arrival side)
C Horizontal shaft 1 Lead box (box)
2 Subsequent box (box)
3 Back lining body 4 Connection frame

D Starting equipment 5 Press wheel 6 Jack 7 Bracket 8 Connecting material

Claims (3)

  A push ring that contacts the rear end surface of the box is arranged behind the start port, and after a connecting material from the opening edge of the start port to the press wheel is arranged, the jack is attached to the push wheel and pulled on the connecting material. A method for constructing a horizontal shaft, wherein the box is pushed out of the start opening by applying a force and moving the push wheel toward the start opening. It is a starting equipment for the propulsion method used when pushing out the box from the starting port,
A push wheel that contacts the rear end surface of the box,
A jack attached to the push ring;
A connecting material from the opening edge of the start opening to the push ring,
The starting equipment, wherein when a tensile force is applied to the connecting member with the jack, the push wheel moves to the starting port side. It is a start-up facility for the propulsion method used to push out the box from the start opening provided in the existing tunnel,
A push wheel that contacts the rear end surface of the box,
A jack attached to the push ring;
A bracket disposed at an opening edge of the start opening;
A connecting material from the bracket to the push ring,
The bracket is fixed to the lining of the existing tunnel,
The starting equipment, wherein when a tensile force is applied to the connecting member with the jack, the push wheel moves to the starting port side.

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