JP4698459B2 - Construction method for underground structures - Google Patents

Description

  The present invention relates to a method for embedding and constructing an underground structure that mainly serves as an underground passage in the ground directly below a track and a road across the track and the road.

  Conventionally, as described in Patent Document 1, as a method for constructing an underground passage by burying an existing underground structure in a ground under a track or a road, at least in an underground structure to be embedded in the ground A holding frame is projected integrally from the front end surface of the upper floor portion, and a plurality of small cylindrical blade edges are slidably fitted back and forth in the holding frame, and the rear end face of the small cylindrical blade edge A propulsion jack is interposed between the front end surface of the upper floor portion of the underground structure, and the tip of the elongated friction cut plate disposed on the upper surface of the underground structure is fixed to the upper surface of the front end portion of each small cylindrical blade edge, By setting the underground structure on the start shaft side with one side across the track or road as the start shaft side and the other side as the reach shaft side, the propulsion jack is extended to sequentially specify the small cylindrical blade edges. Propelled into the ground for a long time, propulsion of this small cylindrical blade Then, following the small cylindrical blade group, the underground structure is propelled along the lower surface of the friction cut plate by the same length, and by repeating this, the underground structure is buried between the starting shaft and the reaching shaft, Construction is being done.

Further, instead of the holding frame, a holding cylinder in which a small cylinder blade edge is slidably inserted back and forth is used, and the holding cylinder provided with the small cylinder blade edge is positioned in front of the upper floor portion of the underground structure. An underground structure is formed by repeatedly performing a work process for propelling the pipe roof for a certain length and a work process for propelling the underground structure for a certain length following the pipe roof. It is also described to promote and embed
Japanese Patent Publication No.59-27833

  However, according to the construction method of the underground structure described above, in order to propel the small cylinder blade edge, a propulsion jack is installed behind each small cylinder blade edge, and the propulsion jack is sequentially extended. Therefore, there is a problem in that the entire device is large-scaled and the construction cost is high, which is uneconomical. For this reason, it is only necessary to install the propulsion jack used for propelling the small cylindrical blade edge behind the small cylindrical blade edge to be propelled next, but the work is extremely complicated and takes a lot of time and effort, Further, there is a problem that the propulsion jack cannot be moved in the structure in which the small cylindrical blade edge is slidably disposed in the holding cylinder as described above.

  Further, the small cylinder blade edge is slidably mounted in the holding frame and the holding cylinder so as to be slidable back and forth, and an elongated friction cut plate disposed on the top surface of the underground structure on the front end upper surface of the small cylinder blade edge. Since the tip of the cylinder is fixed, a gap corresponding to the thickness of the holding frame or holding cylinder is formed between the lower surface of the friction cut plate and the upper surface of the tip of the small blade edge. And the tip of the small cylindrical blade are integrally connected by a member coupled to each other, and this coupling member increases the propulsion resistance of the small cylindrical blade and makes it difficult to perform the propulsion work. There was a fear.

  Further, when propelling the underground structure, the friction cut plate tries to move forward integrally with the underground structure due to the frictional force between the upper surface of the underground structure and the lower surface of the friction cut plate. A tensile force is generated to lift the upper ground with the upper surface of the front end as a fulcrum at the small cylindrical blade edge to which the front end is fixed, increasing the propulsion resistance of the underground structure and smoothing along the lower surface of the friction cut plate There was a problem that it was impossible to promote properly.

  The present invention has been made in view of such problems, and the object of the present invention is to provide each pipe that forms a pipe roof when propelling the pipe roof underground before an underground structure. Can be carried out sequentially by one pipe propulsion means, and at the same time as the propulsion, the excavation means in the pipe is driven by the pipe propulsion means to enable efficient propulsion, and the underground structure is also smooth It is in providing the construction method of the underground structure which can be promoted.

  In order to achieve the above object, the construction method for an underground structure according to the present invention comprises a drilling means for excavating the ground in the front on the front side of the upper floor portion of the underground structure as described in claim 1. In addition, a pipe roof is formed by arranging a plurality of pipes on which the friction cut plate is placed on the upper surface and the front end of the friction cut plate is fixed on the upper surface of the front end. In this state, the pipe roof is slidably supported on the upper surface of the blade edge attached to the front end opening, and in this state, all the pipes forming the pipe roof are sequentially propelled into the ground for a certain length. A friction cut plate on each of the pipes in a method of burying the underground structure in the ground by repeatedly performing a step and a step of propelling the underground structure in the ground for a certain length following this step It extends backward and is slidably placed on the upper surface of the upper floor of the underground structure, and between the rear end of the pipe roof covered with these friction cut plates and the front end of the upper floor of the underground structure. A driving unit for driving the excavating means in each pipe is disposed on the upper surface of the blade edge in the working space formed by the space, and the driving unit is moved laterally to the rear of the pipe to be propelled. It is characterized by digging a certain length sequentially.

Furthermore, the present invention removably attaches the reaction force receiving brackets to the upper surfaces of the rear ends of all the friction cut plates, and when propelling the underground structure, the width direction of the underground structure is set in front of these reaction force receiving brackets. In addition to receiving one reaction force receiving girder installed on the wall, a number of friction cut plate tensioning jacks less than the number of friction cut plates are installed between the reaction force receiving girder and the well wall on the wellhead side of the starting shaft. The extension of these friction-cut plate tensioning jacks prevents all friction-cut plates from pulling backward with a constant tensile force to move together with the underground structure. It is characterized by removing the reaction force receiving girder.

In the construction method of the underground structure constructed as described above, the invention according to claim 2 is directed to the underground structure being pushed from the upper surface of the pipe onto the underground structure during the embedding of the underground structure from the starting shaft to the reaching shaft. Before the friction cut plate placed over the ground is buried in the ground from the shaft of the start shaft by propelling the pipe roof, the front end of a new friction cut plate of a certain length is placed on the rear end surface of the friction cut plate. It is characterized in that the surfaces are butted and joined by welding.

  According to the first aspect of the present invention, in the pipe roof that is propelled underground before the underground structure, the friction cut plates are not formed on the upper surfaces of all the pipes forming the pipe roof. Since it is mounted and its front end is firmly fixed to the upper surface of the front end of the pipe, it can be smoothly propelled while minimizing the resistance received from the front face ground during propulsion. Since the friction cut plate extends rearward from each pipe and is slidably placed on the upper surface of the underground structure, it is formed between the rear end of the pipe roof and the front end surface of the underground structure. The upper part of the working space part can be covered with this friction cut plate array, so that the upper ground is surely collapsed into the working space part. Sealed while it is possible to smoothly buried construction of underground structures.

  Further, in the work space part, a drive part for driving the excavation means in each pipe is disposed on the upper surface of the blade edge forming the floor surface of the work space part. After moving laterally and stopping behind the desired pipe, the drive part is moved forward, so that this drive part is coupled to the excavating means in the pipe to smoothly propel the pipe while excavating the ground in front. Therefore, without installing a driving mechanism for the excavation means and a propulsion jack at the rear end side of each pipe, a plurality of pipes are sequentially and reliably fixed while laterally moving the driving unit. Long, you can dig.

  Further, according to the invention of claim 2, when the underground structure is propelled and buried from the start shaft side to the arrival shaft side, it is placed over the underground structure from the upper surface of the pipe. Before the above-mentioned friction cut plate is buried into the ground from the shaft of the start shaft by propelling the pipe roof, the front end surface of a new friction cut plate of a certain length is brought into contact with the rear end surface of the friction cut plate by welding. Since it is an extension, the upper surface of the upper floor portion of the underground structure can be smoothly slid and brought into contact with the bottom surface of the friction cut plate, and can be smoothly pushed and buried.

Furthermore, according to the present invention , the reaction force receiving brackets are removably fixed to the upper surfaces of the rear ends of all the friction cut plates, and when the underground structures are propelled, the underground structures are placed in front of these reaction force receiving brackets. One reaction force receiving girder arranged in the width direction is received, and the number of friction cut plate tensioned jacks is smaller than the number of friction cut plates between the reaction force receiving girder and the well wall on the wellhead side of the starting shaft. By installing these friction cut plate tensioning jacks, all the friction cut plates are pulled backward with a constant tensile force, so the upper surface of the upper floor part of the underground structure during the propulsion of the underground structure It is possible to reliably prevent the friction cut plate from moving together with the underground structure by the frictional force between the friction cut plate and the lower surface of the friction cut plate. , Precisely and smoothly promote underground construction along its lower surface while retaining the friction cut plate in tension, it can be embedded.

  In addition, since one reaction force receiving girder is received in common on the front surface of the reaction force receiving bracket fixed to the upper surface of the rear end of all the friction cut plates, the number of friction cut plate tension quoted jacks used Therefore, the work efficiency can be improved and the construction cost can be reduced.

  A specific embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a structure where a start shaft B (not shown) is provided from the start shaft B side in the ground directly below a road or a track (hereinafter referred to as a track A). When constructing an underground passage that propels and embeds the underground structure 1 and crosses the track, a pipe roof 2 having a lateral width substantially equal to the width of the underground structure 1 on the front side of the upper floor portion 1a of the underground structure 1 By repeating the step of propelling the pipe roof 2 forward to the reach shaft, and the step of propelling the underground structure 1 by a constant length following this step, It shows a state in which the underground structure 1 is buried in the ground. This underground structure 1 is made of a pre-made reinforced concrete box having a rectangular cross section penetrating in the front-rear direction, and has a blade edge 3 at its front end opening. Wearing.

  The blade edge 3 has a rear end frame portion 3a having substantially the same cross-sectional shape as the rectangular cross section of the underground structure 1 joined to the front end surface of the underground structure 1 and is fixed integrally therewith, and the rear end frame portion 3a. From the upper surface of the upper floor portion 1a of the basement structure 1 to the front, with the same dimension as the thickness of the upper floor portion 1a or the dimension below the thickness of the upper floor portion 1a. A base frame 3b having a fixed length is projected horizontally, and further, a lower frame is formed at the front lower end portion of the rear end frame portion 3a that is shorter than the length of the base plate 3b and whose tip is formed at the blade edge portion. The part 3c protrudes forward, and the front end of the base plate 3b and the lower frame part 3c is inclined obliquely rearward from the upper end to the lower end and is integrally connected by the inclined side frame parts 3d and 3d. In addition, a blade edge portion is formed over the entire length at the front end of the inclined both side frame portions 3d, 3d.

  The rear bottom surfaces of the plurality of pipes 2a forming the pipe roof 2 on the front half portion of the base plate 3b of the blade edge 3 configured in this manner are independently supported so as to be movable forward. I am letting. The pipe 2a is made of a steel pipe having a rectangular cross section having a certain length, and the pipe roof 2 is formed by juxtaposing these pipes 2a in the width direction of the base plate 3b as shown in FIGS. . The upper surface of the pipe 2a is formed so as to be flush with the upper surface of the upper floor portion 1a of the underground structure 1 (thickness).

  In each pipe 2a, a screw auger 4 is integrally provided at the front end of the auger shaft as a means for excavating the front ground, and is rotatably arranged with the cutter head 4a facing forward from the front end opening of the pipe 2a. And the rear end portion of the auger shaft is rotatably supported by the central portion of the end face plate 2b fixed to the rear end of the pipe 2a. As shown in FIGS. 4 and 5, the end face plate 2b A clutch piece 4b is integrally provided at the rear end protruding from the front end.

  Further, a friction cut plate 5 made of a strip steel plate is placed on the flat upper surface of each pipe 2a, and the front end of the friction cut plate 5 is integrally fixed to the upper surface of the front end of the pipe 2a by welding. The width of the friction cut plate 5 is formed to be approximately equal to the width of the pipe 2a and the opposing end surfaces of the adjacent friction cut plates 5 and 5 are in sliding contact with each other and arranged side by side. As shown in FIG. 1 and FIG. 2, the above-mentioned start is performed with all the friction cut plates 5 extended rearward from the rear end of the pipe 2 a and the rear portion placed on the upper surface of the upper floor portion 1 a of the underground structure 1. The reaction force receiving bracket 5a is removably fixed to the upper surface of the rear end of the friction cut plate 5 and is exposed rearward from the wellhead of the vertical shaft B.

  Further, a space portion on the base plate 3b of the blade edge 3 between the rear end of the pipe 2a forming the pipe roof 2 and the front end surface of the upper floor portion 1a of the underground structure 1 is formed in the work space portion 6. The working space 6 is covered with an intermediate portion in the longitudinal direction of the friction cut plate row extending in an installed state from the upper surface of the rear end of the pipe 2a to the upper surface of the upper floor portion 1a of the underground structure 1. The intermediate portion supports the upper ground and prevents the earth and sand from collapsing in the work space 6.

  In the work space 6 on the base plate 3b of the blade edge 3, a laterally movable carriage 7 is arranged that can move in the width direction of the underground structure 1 along the front end surface of the upper floor 1a of the underground structure 1. A drive unit 8 for rotationally driving the screw auger 4 inserted in each pipe 2a is arranged on the laterally movable carriage 7 so as to be movable in the front-rear direction. Specifically, as shown in FIGS. 4 and 5 above, the front surface of the rear end frame portion 3a of the blade edge 3 abutting on the base plate 2b of the blade edge 3 and the front end surface of the upper floor portion 1a of the underground structure 1; Rails 10 and 10 'are laid in the width direction of the pipe roof 2, and wheels 7a and 7a rotatably supported on both sides of the front end surface of the laterally moving carriage 7 are placed on the rail 10 on the base plate 2b. A sliding member 7b having a U-shaped cross section fixed to both sides of the rear end surface of the laterally moving carriage 7 is slidably engaged with the other rail 10 'so that the laterally movable carriage 7 is connected to the pipe roof. 2 is arranged so as to be able to reciprocate in the width direction.

  Further, a traveling drive motor 11 is installed at the center of the rear end portion of the laterally moving carriage 7, and a pinion 12 is fixed to a rotating shaft protruding downward from the traveling drive motor 11, and the pinion 12 is attached to the blade edge 3. The lateral movement cart 7 is reciprocated on the base plate 3b in the width direction of the underground structure 1 by meshing with a rack 13 fixed in parallel with the rail 10 'on the front surface of the rear end frame 3a. It is configured to be movable. Further, a front / rear moving table 9 having the drive unit 8 provided on the upper surface is placed on the laterally moving carriage 7, and a wheel 9 a is rotatably supported on the front and rear portions at both end portions of the front / rear moving table 9. 9a are inserted into and supported by the rail portions 14 and 14 formed of concave grooves provided on both side surfaces of the laterally moving carriage 7 over the entire length thereof.

  The drive unit 8 provided on the front / rear moving table 9 is fixed to the rotation drive motor 8a mounted on the center of the front / rear movement table 9 and the front end of the rotation shaft of the rotation drive motor 8a. A clutch piece 8b that engages with and disengages from a clutch piece 4b that is fixed to the rear end of the auger shaft of the screw auger 4, and pipe propulsion jacks 8c and 8c disposed on both sides of the front and rear moving base 9, The front end portions of the pipe propulsion jacks 8c, 8c are fixed to the upper surfaces of both side portions of the front / rear moving table 9, and the ends of the rods of the pipe propulsion jacks 8c, 8c facing rearward are integrally connected by the spreader 15, By extending the rods of the propulsion jacks 8c and 8c, the spreader 15 is received by the rear end frame portion 3a of the blade edge 3, and the propulsion reaction force is applied to the rear end frame portion 3a to advance the front / rear moving table 9. The clutch piece 8b of the rotary drive motor 8a A receiving member 9b that is engaged with the clutch piece 4b at the rear end of the auger shaft of the clew auger 4 and fixed on the front end portion of the front / rear moving table 9 projects backward from the end face plate 2b of the pipe 2a. The pipe 2a is propelled by being brought into contact with the frame 2c.

  Further, as shown in FIGS. 5 and 6, locking pieces 16, 16 project downward from the lower surfaces of both sides of the rear end of the spreader 15, while the upper surfaces of both sides of the rear end of the laterally moving carriage 7. A stopper piece 17 that is disposed on the front side of the locking pieces 16 and 16 and receives the front end surface of the locking piece 16 protrudes upward, and is provided on the pipe propulsion jacks 8c and 8c. When the rod is extended, the locking piece 16 is separated backward from the stopper piece 17, and when the rod is contracted, the locking piece 16 is received by the stopper piece 17, and the rod is further contracted from this state. Thus, the back-and-forth moving base 9 is configured to retreat with the receiving portion as a fulcrum.

  On the other hand, in FIG. 1 and FIG. 2, the rear part is extended rearward from the rear end on the pipe 2a, and the rear part is placed on the upper surface of the upper floor part 1a of the underground structure 1 so On the exposed friction cut plate 5, a friction cut plate tensioning jack 18 made of a hydraulic jack is disposed as a pulling means for applying a tensile force to the rear end portion of the friction cut plate 5 backward. ing.

  The front end of this friction cut plate tensioned jack (hereinafter referred to as hydraulic jack 18) is placed on the earth retaining wall 20 of the ground on the entrance side of the start shaft B, and the length thereof is directed in the direction crossing the friction cut plate row. The rod is supported by a fixed reaction force support steel 21 and the tip of the rod of the hydraulic jack 18 facing rearward is directly attached to the front surface of the reaction force receiving bracket 5a fixed to the upper surface of the rear end portion of the friction cut plate 5. Alternatively, it is received through a plurality of spacer pieces 19 having a certain thickness, and the rod of the hydraulic jack 18 is actuated in the extending direction so that a tensile force is applied between the reaction force supporting steel material 21 and the reaction force receiving bracket 5a. It is configured so that a constant tensile force is applied to the friction cut plate 5 by this tension force.

  The underground structure 1 is installed on the bottom slab 22 having a flat top surface laid on the bottom surface of the start shaft B so as to be slidable in the front-rear direction. A plurality of underground structure propulsion jacks 26 are disposed between the reaction force receivers 24 disposed on the base plate via a plurality of spacers 25, and the front end surfaces of these propulsion jacks 26 are joined to the rear end surface of the underground structure 1. The tip of the rod of the propulsion jack 26 that is fixed in a state of being pressed against the rear surface of the pressed ring 27 and protrudes rearward is brought into contact with the front surface of the foremost spacer 25 made of a plate material or a frame material having a certain thickness. The underground structure 1 is configured to be propelled and buried in the ground from the wellhead of the start shaft B by extending the rod of the propulsion jack 26 after being contacted and received.

  The underground structure 1 is propelled and buried by sequentially propelling all the pipes 2a constituting the pipe roof 2 into the ground by a certain length and after the certain length of propulsion process of the pipe roof 2. This is performed by sequentially repeating the step of propelling the object 1 by the same length. In addition, when the friction cut plate 5 drawn from the pipe 2a to the upper floor 1a of the underground structure 1 behind it is propelled together with the pipe 2a and embedded in the ground for a certain length, it starts. The front end surface of the friction cut plate 5 having a predetermined length is abutted against the rear end surface of the friction cut plate 5 exposed in the shaft B, and is added by welding.

  In order to propel all the pipes 2a constituting the pipe roof 2 by a certain length, first, the rear portion protruding into the start shaft B in the friction cut plate 5 placed on one pipe 2a to be propelled. A hydraulic jack 18 as a pulling means is arranged on the upper side as shown in FIG. 2, and its front end surface is abutted against the rear surface of the reaction force support steel material 21 and fixed in a state of being received, and the rod of the hydraulic jack 18 is fixed. The front end is received by a reaction force receiving bracket 5a fixed to the upper surface of the rear end portion of the friction cut plate 5 via a plurality of spacer pieces 19 having a certain thickness. The hydraulic jack 8a is interposed between the reaction force supporting steel material 21 and the reaction force receiving bracket 5a so as to be in a stretched state by applying a constant load in the extending direction of the rod.

  On the other hand, in the work space portion 6 provided on the front side of the upper floor portion 1a of the underground structure 1, the one to be propelled by driving the laterally moving carriage 7 and running on the rails 10, 10 ′. The pipe propulsion jacks 8c and 8c disposed on both sides of the front and rear moving base 9 on the laterally moving carriage 7 are moved as shown in FIG. By extending the rod, the spreader 15 connecting the rear ends of the rods is brought into contact with and received by the rear end frame portion 3a of the blade edge 3, and the reaction force is applied to the rear end frame portion 3a. When the rod is further extended, the front / rear moving table 9 moves forward, and the clutch piece 8b attached to the front end of the rotation shaft of the rotation drive motor 8a of the drive unit 8 installed on the front / rear moving table 9 is moved to the screw auger 4. The clutch piece 4b at the rear end of the auger shaft is engaged.

  When the screw auger 4 is rotated by operating the rotational drive motor 8a in this state and the pipe propulsion jacks 8c and 8c are further extended, as shown in FIG. The forward / backward moving table 9 moves forward with the propulsion reaction force received, and the pipe 2a is propelled while excavating the front ground by the cutter head 4a of the screw auger 4. At this time, the rod of the hydraulic jack 18 is contracted by a length corresponding to the propulsion amount of the pipe 2a while maintaining a state in which a certain load is applied to the hydraulic jack 18 and a constant tensile force is applied to the friction cut plate 5. By doing so, the pipe 2 a is dug together with the friction cut plate 5.

  When a constant tensile force is applied to the rear end portion of the friction cut plate 5 by the hydraulic jack 18, the tensile force is transmitted to the fixing portion by welding between the front end of the friction cut plate 5 and the front end of the pipe 2a, and the pipe 2a. As a result, an acting force is generated to warp upward against the load received from the upper ground with the base plate 3b of the blade edge 3 as a fulcrum. With this acting force, the pipe 2a can be smoothly and accurately propelled while maintaining the horizontal state as the planned propulsion direction without being bent downward by a load from the upper ground.

  At this time, the tensile force applied to the pipe 2a by the hydraulic jack 18 via the friction cut plate 5 is naturally set smaller than the propulsive force by the pipe propulsion jacks 8c, 8c. When the front end portion of the pipe 2a tries to bend downward by the load of the upper ground applied to the front end portion of the pipe 2a protruding forward from the plate 3b, the rod is attached to the hydraulic jack 18 via the friction cut plate 5. Since the force to try to contract is generated and the tensile force to maintain the horizontal state increases, the pipe 2a can be propelled in the correct direction simply by applying a relatively small load to the hydraulic jack 18. Can do. The excavated earth and sand are carried out backward by the screw auger 4 and discharged into the blade edge 3 through a discharge port (not shown) opened in the lower surface of the rear end portion of the pipe 2a. The soil and the ground in front of the blade 3 are discharged and removed from the blade 3 to the start shaft B side through the underground structure 1 together with the soil excavated by an appropriate excavating means.

  In this way, after digging one pipe 2a into the ground for a certain length and then contracting the pipe propulsion jacks 8c, 8c, the spreader 15 is separated forward from the rear end frame portion 3a of the blade edge 3 which is a reaction force receiver. At the same time, the locking piece 16 projecting downward from the spreader 15 abuts on the rear end surface of the stopper piece 17 projecting upward from the rear end of the laterally moving carriage 7 and is further apart from it. When the pipe propulsion jacks 8c, 8c are further contracted from this state, the forward / backward moving base 9 moves backward, and the clutch piece 4b connecting the rotary shaft of the rotary drive motor 8a and the auger shaft of the screw auger 4 is connected. , 8b is uncoupled.

  Thereafter, the laterally moving carriage 7 is laterally moved behind the next pipe 2a to be propelled, and the rods of the pipe propulsion jacks 8c and 8c are again extended in the same manner as described above, so that the spreader 15 is attached to the rear end frame portion of the blade mouth 3. Further, the rotary drive motor 8a is connected to the auger shaft of the screw auger 4 via the clutch pieces 4b and 8b by extending the rod and advancing the back-and-forth moving table 9 in this state. The screw auger 4 is rotated and the pipe propulsion jacks 8c and 8c are propelled by the same length as the pipe 2a propelled first.

  At this time, similarly to the above, the hydraulic jack 18 is disposed on the rear portion of the friction cut plate 5 placed on the pipe 2a and projecting into the start shaft B, and the rod of the hydraulic jack 18 is extended. The hydraulic jack 18 is interposed between the reaction force supporting steel material 21 and the reaction force receiving bracket 5a so as to be in a stretched state by applying a certain load in the direction to be applied. In this case, one hydraulic jack 18 used for propelling one pipe 2a may be replaced on the rear end portion of the friction cut plate 2 on the pipe 2a to be propelled next, as shown in FIG. As described above, two (or two or more) hydraulic jacks 18 and 18 are prepared in advance, and the hydraulic jacks 18 and 18 are to be propelled first and the pipe 2a to be propelled next. One hydraulic jack 18 previously used for propelling the pipe 2a should be propelled next to this pipe 2a during the propulsion of the next pipe 2a by the other hydraulic jack 18. It is desirable to rearrange the pipe 2a.

  Thereafter, the pipes 2a are dug sequentially in the same manner, and as shown in FIG. 8, when all these pipes 2a constituting the pipe roof 2 are dug for a certain length, the rear ends of all the friction cut plates 2 Since the vertical front surface of the reaction force receiving bracket 5a fixed to the upper surface of the part is in a state of being flush with the width direction of the underground structure 1, the width of the pipe roof 2 is increased as shown in FIG. A reaction force receiving girder 28 having substantially the same length is disposed so as to cross over the rear part of the friction cut plate row, and the rear surface of the reaction force receiving girder 28 is connected to all the reaction members that are continuously flush. The force receiving bracket 5a is received through the plurality of spacer pieces 19 on the front surface.

  After that, several hydraulic jacks 18 '(four in the figure) are interposed between the reaction force supporting steel material 21 and the reaction force receiving beam 28 at a desired interval in the width direction of the friction cut plate row. The front end face is supported by the reaction force support steel material 21 and the tip of the rod facing backward is pressed against the reaction force receiving girder 28, and a load is applied to these hydraulic jacks 18 'so that the reaction force receiving girder 28 receives the reaction force receiving bracket. A constant tensile force is applied to all the friction cut plates 5 toward the rear via 5a.

  In this state, a plurality of propulsion jacks 26 arranged in the start shaft B are extended, and a reaction force is applied to the reaction force receiver 24 via the spacer 25 to attach the underground structure 1 to the upper floor portion 1a. As shown in FIG. 10, the upper surface is propelled forward by the same propulsion length as the pipe roof 2 while being brought into sliding contact with the lower surface of the friction cut plate row. At this time, the blade edge 3 attached to the opening at the front end of the underground structure 1 moves forward in contact with the lower surface of the pipe roof 2 on the front surface of the base plate 3b integrally with the underground structure 1. While excavating the front ground, the front ground surrounded by the blade edge 3 is excavated by appropriate excavating means. On the other hand, in synchronization with the propulsion of the underground structure 1, the friction cut plates 5 are contracted by contracting the several hydraulic jacks 18 ′ while maintaining the state in which the constant tensile force is applied to all the friction cut plates 5. By making the immovable state, the propulsion of the underground structure 1 prevents the friction cut plates 5 from moving forward due to the sliding force with the upper floor portion 1a of the underground structure 1.

  As the several hydraulic jacks 18 ', the hydraulic jack 18 used as the pulling means when the pipe 2a is dug is reused, and when the number of the hydraulic jacks 18 is insufficient, the hydraulic jack having the same structure is used. However, a hydraulic jack different from the above-described hydraulic jack 18 in which all the hydraulic jacks 18 ′ are used when the pipe 4 is dug may be adopted. In addition, when the hydraulic jack 18 ′ is disposed, if there is no gap for interposing the reaction force receiving beam 28 between the hydraulic jack 18 ′ and the spacer piece 19, a spacer having a front and rear width in which the gap is provided. Use a piece.

  In this way, by applying a constant tensile force to the friction cut plate 5 backward by the hydraulic jack 18 ', the front end of the pipe 2a is prevented from being bent downward, while the front and rear on the laterally movable carriage 7 are prevented. A step of sequentially excavating the pipes 2a in the horizontal direction by the drive unit 8 disposed on the moving table 9 and propelling the pipe roof 2 made of these pipe rows into the ground ahead in a fixed length toward the reaching shaft side; After this step, the hydraulic jack 18 'applies a constant tensile force to the friction cut plate 5 in the same manner as described above to prevent the friction cut plate 5 from moving forward, and is arranged on the start shaft B side. The step of extending the propulsion jack 27 and contacting the lower surface of the pipe roof 2 by the same distance as the pipe roof 2 to propel the underground structure 1 forward is repeated.

  At this time, each time the pipe roof 2 is propelled for a certain length, the friction cut plate 5 in which only the front end of each pipe 2a is fixed to the upper surface of the front end of the pipe 2a by welding is also integrally propelled to the start shaft B. Therefore, the length of the portion protruding from the hydraulic jack 18 (18 ') as the tension means and the reaction force receiving bracket 5a fixed to the upper surface of the rear end of the friction cut plate 5 are reduced. The length of the rear end portion of the friction cut plate 5 is shortened, and the spacer piece 19 is removed accordingly, but the hydraulic jack 18 (18 ' ) Can no longer be interposed, the reaction force receiving brackets 5a of all the friction cut plates 5 are cut out, and new friction cut plates having a fixed length are formed on the rear end surfaces of these friction cut plates 5. The welding is performed in a state where the front end surfaces are joined together, and the pipe roof 2 is propelled again, and the propulsion of the underground structure 1 is repeated after the propulsion again in the same manner as described above.

  Similarly, each time the underground structure 1 is excavated into the ground for a predetermined length, a spacer 25 having a thickness corresponding to the excavation length in the start shaft B is provided on the rear side of the propulsion jack 26 as shown in FIG. In addition, when the length of the underground passage to be constructed by the underground structure 1 is long, the underground structure of a certain length obtained by dividing the length of the underground passage into several parts is sequentially promoted while being joined and connected. The underground shaft by this underground structure 1 is constructed between the starting shaft B and the reaching shaft. In the above-described embodiment, the underground structure 1 is constructed on the direct ground board of the track A, but it is needless to say that the underground structure 1 can be constructed by the same method as described above even under the road.

A simplified longitudinal side view of a state in which a friction cut plate is propelled into the ground for a certain length in advance of an underground structure. The simplified plan view. The simplified front view of a pipe roof. The partially abbreviate | omitted top view of the state which is propelling a pipe with a horizontal movement trolley | bogie. The vertical side view of the state which moved the horizontal movement trolley to the back of the pipe which should be propelled. The longitudinal front view in the XX line. The vertical side view of the state which is pushing the pipe. A simplified longitudinal side view of a pipe roof propelled for a certain length. The simplified top view of the state which has arrange | positioned the reaction force receiving girder. A simplified longitudinal side view of an underground structure propelled into the ground for a certain length. A simplified longitudinal side view of a state where an underground structure is further propelled into the ground.

Explanation of symbols

A Track B Start shaft 1 Underground structure 2 Pipe roof
2a Pipe 3 Cutting edge 4 Screw auger 5 Friction cut plate
5a Reaction force receiving bracket 6 Working space 7 Horizontally moving carriage 8 Drive unit
8a Rotation drive motor
8c Pipe propulsion jack 9 Back and forth moving platform
18 'Friction cut plate fixing jack
28 Reaction force girder

Claims (2)

An excavation means for excavating the front ground is provided on the front side of the upper floor portion of the underground structure, and the friction cut plate is placed on the upper surface and the front end of the friction cut plate is fixed to the upper surface of the front end. A pipe roof is formed by arranging a plurality of pipes side by side, and this pipe roof is slidably supported forward on the upper surface of the blade edge attached to the front end opening of the underground structure. In this step, all the pipes forming the pipe roof are sequentially propelled into the ground for a certain length, and this step is followed by a step of propelling the underground structure into the ground for a certain length. In the method of burying the underground structure in the ground, the friction cut plate on each pipe is extended rearward and slidably placed on the upper surface of the upper floor portion of the underground structure. The excavation means in each pipe on the upper surface of the blade edge in the work space formed by the space between the rear end of the pipe roof covered with the friction cut plate and the front end of the upper floor of the underground structure A drive unit is installed to drive the pipe, and the drive unit is moved laterally to the rear of the pipe to be propelled to sequentially dig the pipe at a fixed length, while a reaction force receiving bracket is mounted on the rear end upper surface of all the friction cut plates. Removably fixed, when propelling the underground structure, one reaction force receiving girder arranged in the width direction of the underground structure is received in front of these reaction force receiving brackets and this reaction force receiving By installing fewer friction-cut plate tension quote jacks than the number of friction cut plates between the girder and the pit wall of the starting shaft, all of the friction cut plate-length quote jacks can be extended. Thereby preventing the co-movement and underground structures and tensioning backward with the re action cut plate with a constant tension, underground during propulsion of the pipe roof, characterized in that removing the above-mentioned reaction force receiving girder structure Construction method of things.   The underground structure is propelled and buried from the start shaft to the arrival shaft, and the friction cut plate placed over the underground structure from the upper surface of the pipe is grounded from the entrance of the start shaft by the pipe roof. 2. The underground structure according to claim 1, wherein a front end surface of a new friction cut plate having a predetermined length is brought into contact with a rear end surface of the friction cut plate before being embedded therein, and is added by welding. Construction method.

Images