JP4731317B2 - How to build an underpass - Google Patents

Description

  The present invention relates to an underground passage construction method, and more particularly, to an underground passage construction method in which an underground passage is formed by replacing a pipe roof formed in the ground with an underground passage outline structure with a friction cut member remaining in the ground.

  For example, as a method of constructing an underground passage in a state where it crosses the existing railway track or the lower ground of the road, for example, the existing railway track or road is lowered to the ground above the planned underground passage where the underground passage is planned to be constructed. A pipe roof that is supported and protected from, for example, by forming a plurality of circular steel pipes arranged side by side in a horizontal direction, and constructing an underground passage by excavating the lower ground while supporting the pipe roof After securing a working space, a method of constructing an underground passage by installing a formwork or placing concrete has been generally adopted. Because it is necessary to form a work space with a considerably larger cross section, it is not an efficient construction method, and it tends to affect existing railway lines and roads above.

  For this reason, as an alternative to the conventional method of constructing an underground passage by providing a work space below the pipe roof, the pipe roof formed in the ground, for example, made of precast, with the friction cut member remaining in the ground An underpass construction method has been developed in which an underpass is formed by replacing the underpass with an underpass structure (see, for example, Patent Document 1).

  In the underpass construction method described in Patent Document 1, for example, as shown in FIGS. 9A to 9J, the friction cut member 51 is fixed to a surface arranged along the outer periphery of the planned underpass 50 having a rectangular cross section. The plurality of box-shaped pipe members 52 are press-fitted in parallel to at least the upper floor position 50a of the planned underpass 50, for example, from the starting shaft 53 to the reaching shaft 54 (see FIGS. 9A and 9B). ), And a pipe roof 55 penetrating the planned underpass 50 is formed in the ground (see FIGS. 9C and 9D). Thereafter, at least the end surface of the upper floor portion 56a of the underground passage outer structure 56 having a rectangular cross section made of, for example, a precast is brought into contact with the end surface of the pipe roof 55, for example, with an intermediate push jack 57 interposed therebetween. At the rear end of the body 56, a push jack 58 for propelling the underground passage outline structure 56 is installed (see FIGS. 9E and 9F). Then, the underpass outer structure 56 is propelled while excavating and removing the sand on the face of the inner tip of the underpass outer structure 56 using the blade member 59 or the like, and the friction with the fixed release from the box-shaped pipe member 52 is released. With the cut member 51 left in the ground, at least the pipe roof 55 at the upper floor position 50a is pushed out and replaced with the underground passage outer structure 56 (see FIGS. 9 (g) and 9 (h)). An underpass 60 is formed by the underpass structure 56.

Here, in the construction method of the underground passage described in Patent Document 1, the underground passage 60 is formed by propelling the underground passage outer structure 56 while replacing the pipe roof 55, so the excavation cross section becomes larger than the cross section of the underground passage 60. This makes it possible to construct an efficient underpass. In addition, since the underpass structure 56 is propelled while the friction cut member 51 is left in the ground, it is difficult to affect the existing upper railway line, road, etc., and the friction cut member 51 functions as a guide. It is possible to smoothly propel the underground passage outline structure 56 along the friction cut member 51 without directly contacting the upper ground. Furthermore, the box-shaped pipe member 52 constituting the pipe roof 55 replaced with the underpass outer shell structure 56 can be recovered and reused.
JP-A-1-29597

  On the other hand, in the method for constructing an underground passage described in Patent Document 1, in the process of forming the pipe roof 55, the work of pressing each box-shaped pipe member 52 into the ground is performed by removing the earth and sand at the tip of the box-shaped pipe member 52. For example, an auger disposed inside the box-shaped pipe member 52 or an operator who has entered the box-shaped pipe member 52 performs excavation while taking in the box-shaped pipe member 52 and also uses the propulsion device 61 (FIG. )), The box-shaped pipe member 52 is pushed out, and after the box-shaped pipe member 52 is pressed into the ground of the planned underground passage 50, the pipe roof 55 is replaced by the box-shaped pipe member 52. It is desirable to hold the surrounding ground in a more stable state until the underpass structure 56 is installed.

  For example, due to an unexpected cobblestone or hard ground, the ground outside the cross section of the box-shaped pipe member 52 is shaved, and the presence of voids and the loosening of the ground are expected outside the friction cut member 51. In such a case, if there is a means for quickly eliminating such a gap or loosening of the ground, it becomes possible to work in a more stable state.

  In the underpass construction method described in Patent Document 1, since the friction cut member 51 is attached so as to cover the outer surface of the box-shaped pipe member 52 constituting the pipe roof 55, the friction cut member 51 is traversed. Since it is difficult to eliminate the gap and loosening of the ground by injecting the solidified material into the outer ground from the inside of the box-shaped pipe member 52, drilling is performed from the starting shaft 53 or the reaching shaft 54, It has been considered to inject an injection solidified material into the ground outside the friction cut member 51 through the formed borehole.

  However, in this method of injecting the solidified material through the borehole, it takes a lot of labor and time to prepare and drill the borehole. When away from the vertical shaft 53 or the reaching vertical shaft 54, it is possible to inject the injection solidified material into the ground outside the friction cut member 51 more quickly from the viewpoint of suppressing the deformation of the natural ground more effectively. Development of the means to make is desired. In addition, after the subterranean shell structure 56 is installed in place of the pipe roof 55, the ground outside the friction cut member 51 is formed through an injection hole formed in the subway shell structure 56 by the work from the inside. It is conceivable to inject the solidified material into the pipe, but the construction will be carried out after a long period of time, and the remaining friction cut member 51 will be in the way, and the solidified material will be injected well outside this. It is possible that you cannot do it.

  The present invention is technically specific to a method for constructing an underground passage as described above, in which an underground passage is formed by replacing the pipe roof formed in the ground with an underground passage outline structure with the friction cut member remaining in the ground. It was made by paying attention to the problem, enabling the injection solidified material to be easily and quickly injected into the ground outside the friction cut member attached to the box-shaped pipe member constituting the pipe roof. An object of the present invention is to provide a method for constructing an underground passage that can be constructed in a stable state.

  In the present invention, a plurality of box-shaped pipe members each having a friction cut member fixed to a surface arranged along the outer periphery of the planned underground passage having a rectangular cross section are arranged in parallel in at least the upper floor position of the planned underground passage. After forming the pipe roof penetrating through the planned underground passage portion into the ground, at least an end surface of the upper floor portion of the underground passage outline structure having a rectangular cross section is brought into contact with the end surface of the pipe roof, and the underground passage outer structure While excavating and removing the sand on the face of the inner end of the body while excavating the subsurface outer structure, the friction cut member released from the fixation with the box-shaped pipe member is left in the ground and at least the upper floor By constructing an underground passage by forming the underground passage by the underground passage structure in the planned underground passage portion by extruding the pipe roof at the position and replacing the underground passage structure with the underground passage outline structure. In the method, the friction cut member and the box-shaped pipe member are fixed and released from a plurality of inner bolt holes formed in the box-shaped pipe member, and a plurality of outer bolt holes formed in the friction cut member. Are fixed by screwing and fixing the bolts, and when the box-shaped pipe member is press-fitted into the ground, the fixing bolts at the locations where the injection solidifying material is injected are connected to the inner bolt holes and A friction cutting member is obtained by removing the outer bolt hole and replacing the injection jig, and injecting the injection solidified material into the ground outside the friction cut member from the inside of the box-shaped pipe member via the injection jig. The above object has been achieved by providing a method for constructing an underpass characterized by stabilizing the ground outside

  In the underpass construction method according to the present invention, the fixing bolt has the tip position substantially matched with the outer opening surface of the outer bolt hole formed in the friction cut member, and the inner bolt hole and the outer bolt. It is preferable to be screwed into the bolt hole.

  Further, in the method for constructing an underground passage according to the present invention, the injection solidified material is applied from the inside of the box-shaped pipe member to the ground outside the friction cut member through an injection jig attached to the inner bolt hole and the outer bolt hole. It is preferable to perform the injection operation for each box pipe member that is press-fitted one by one.

  Furthermore, in the method for constructing an underground passage according to the present invention, an injection solidification material is injected from the inside of the box-shaped pipe member to the ground outside the friction cut member via an injection jig attached to the inner bolt hole and the outer bolt hole. It is also possible to perform the injection operation by press-fitting a plurality of the box-shaped pipe members and then collectively performing the operations on the plurality of box-shaped pipe members.

  According to the present invention, in a construction method of an underground passage that forms an underground passage by replacing the pipe roof formed in the ground with an underground passage outline structure with the friction cut member remaining in the ground, the box constituting the pipe roof The solidified material can be easily and quickly injected into the ground outside the friction cut member attached to the shaped pipe member, and the underground passage can be constructed in a more stable state.

  A method for constructing an underpass according to a preferred embodiment of the present invention includes a pipe roof 55 formed in the ground shown in FIGS. 9A to 9J, for example, precast while the friction cut member 51 is left in the ground. In the method of constructing an underground passage 60 that forms an underground passage 60 by replacing the made underground passage outer structure 56, injection solidification is performed on the ground outside the friction cut member 51 attached to the box-shaped pipe member 52 constituting the pipe roof 55. This material is used to allow the material to be easily and quickly injected and to construct the underground passage 60 in a more stable state.

  That is, in the method for constructing an underground passage according to the present embodiment, a plurality of box-shaped pipe members 52 each having a friction cut member 51 fixed to a surface arranged along the outer periphery of the rectangular underground passage 50 are arranged in the planned underground passage 50. After the pipe roof 55 penetrating the planned underground passage 50 is formed in the ground in a state parallel to at least the upper floor position 50a, the end surface of the pipe roof 55 has a small number of underground passage outer structures 56 having a rectangular cross section. And the end face of the upper floor portion 56a are brought into contact with the intermediate push jack 57 interposed therebetween, and the underground passage outline structure 56 is driven while excavating and removing the sand and sand at the inner end of the underground passage outline structure 56, thereby forming a box shape. With the friction cut member 51 released from the fixing with the pipe member 52 left in the ground, at least the pipe roof 55 at the upper floor position 50a is pushed out to underground In the construction method of forming the underground passage 60 by the underground passage outer structure 56 in the planned underground passage portion 50 by replacing the outer structure 56, a friction cut member 51 and a box-shaped pipe member 52 are provided as shown in FIGS. Are fixed to each other and screwed together with the plurality of inner bolt holes 12 formed in the box-shaped pipe member 52 and the plurality of outer bolt holes 11 formed in the friction cut member 51, respectively. This is done by attaching and detaching the fixing bolt 10. Then, when the box-shaped pipe member 52 is press-fitted into the ground, the fixing bolt 10 is removed from the inner bolt hole 12 and the outer bolt hole 11 at the location (see reference numeral 19 in FIG. 4) where the injection solidifying material is injected, and an injection jig. 13 is replaced, and the ground outside the friction cut member 51 is stabilized by injecting the solidified material into the ground outside the friction cut member 51 from the inside of the box-shaped pipe member 52 via the injection jig 13. It is supposed to let you.

  According to this embodiment, as shown in FIG. 1, the box-shaped pipe member 52 is a hollow box-shaped pipe member having a substantially rectangular cross section (substantially square cross section in the present embodiment) with four corners curved. For example, it is made of a steel plate having a thickness of about 19 mm and has a cross section with a size of about 800 mm in length and width, for example, and has a length of about 6000 mm, for example. The box-shaped pipe member 52 is provided with a substantially triangular connection plate 23 projecting inward from four corners at the opening end face portions at both ends, and is connected to a connection hole 23 a formed in the connection plate 23. By tightening a bolt (not shown), the box-shaped pipe member 52 can be added while being sequentially connected in the length direction with press-fitting into the ground.

  The side plates 14a and 14b disposed on both sides of the box-shaped pipe member 52 in the parallel direction have a pair of upper and lower outer guide ribs 15a on the outer side of one side plate 14a, and upper and lower sides on the outer side of the other side plate 14b. A pair of inner guide ribs 15b are provided so as to protrude in a strip shape over the entire length in the length direction. When the next box-shaped pipe member 52 is press-fitted into the ground adjacent to the box-shaped pipe member 52 previously installed in the ground, it is provided on the side plate 14a of one box-shaped pipe member 52. A pair of inner guide ribs 15b provided on the side plate 14b of the other box-shaped pipe member 52 is fitted between the pair of outer guide ribs 15a, and the guide ribs 15a and 15b are guided. Thus, the plurality of box-shaped pipe members 52 can be press-fitted with high accuracy into a predetermined installation position along the previously-installed box-shaped pipe member 52.

  Furthermore, in this embodiment, the box-shaped pipe member 52 that is press-fitted in parallel into the ground of the upper floor position 50 a (see FIG. 9) of the planned underpass 50 is disposed along the outer periphery of the planned underpass 50. The friction cut member 51 is detachably fixed and attached to the upper surface plate 16 so as to cover the upper surface of the upper surface plate 16 serving as a surface. The friction cut member 51 is a steel plate member having a thickness of, for example, about 12 mm. The friction cut member 51 has substantially the same width as the box-shaped pipe member 52 and is attached over the entire length of the box-shaped pipe member 52. Further, the lap plate 17 is welded and joined to the friction cut member 51, for example, on the upper surface of the friction cut member 51 along one side edge in the width direction. It sticks out and is attached. When the next box-shaped pipe member 52 is press-fitted into the ground adjacent to the box-shaped pipe member 52 previously installed in the ground, for example, the friction fixed to one box-shaped pipe member 52. By wrapping the side edge of the friction cut member 51 fixed to the other box-shaped pipe member 52 along the lower surface of the lap plate 17 of the cut member 51, the seam portions of the friction cut members 51 on both sides are wrapped. The plate 17 can be firmly covered without a gap.

  In the present embodiment, the friction cut member 51 and the box-shaped pipe member 52 include a plurality of inner bolt holes 12 formed in the box-shaped pipe member 52 and a plurality of outer bolt holes 11 formed in the friction cut member 51, respectively. The fixing bolts 10 are screwed and fastened together so that the fixing can be released and fixed together. That is, according to the present embodiment, the upper surface plate 16 of the box-shaped pipe member 52 is formed with the inner bolt holes 12 perforated in two rows at a pitch of about 3 m in the length direction, and the friction cut member. In 51, outer bolt holes 11 are formed at positions corresponding to the inner bolt holes 12. When the friction cut member 51 is attached so as to cover the upper surface plate 16 of the box-shaped pipe member 52, the inner bolt holes 12 and the outer bolt holes 11 are aligned with each other, as shown in FIG. A plurality of through bolt holes can be formed easily.

  In addition, the friction cut member 51 is fixed to the box-shaped pipe member 52 by screwing and fastening the fixing bolt 10 into the through bolt hole in which the inner bolt hole 12 and the outer bolt hole 11 are matched. 52 is press-fitted into the upper floor position 50 a of the planned underground passage 50 together with the upper outer peripheral surface of the planned underground passage 50 having a rectangular cross section. Further, the friction cut member 51 is formed by the underground passage outline structure 56 so as to replace the underground passage outline structure 56 after the pipe roof 55 is formed by press-fitting a plurality of box-shaped pipe members 52 into the ground in parallel. When the pipe roof 55 is pushed out, the fixing bolt 10 is removed from the inside of the box-shaped pipe member 52 and the fixed state with the box-shaped pipe member 52 is released, so that the pipe roof 55 is left in the ground. This makes it possible to effectively hold the upper ground when the pipe roof 55 is replaced by the subway outer shell structure 56 without being disturbed by the friction cut member 51, such as the existing existing railroad tracks and roads above. It becomes possible not to affect.

  Here, in this embodiment, when the fixing bolt 10 is screwed and fastened to the inner bolt hole 12 and the outer bolt hole 11 with the washer 18 interposed between the fixing bolt 10 and the upper surface plate 16 of the box-shaped pipe member 52. The length L from the neck to the tip excluding the head 10a of the fixing bolt 10 so that the position of the tip substantially matches the outer opening surface of the outer bolt hole 11 formed in the friction cut member 51 (see FIG. 2), the nominal length of the bolt is substantially equal to the sum of the thickness of the washer 18, the thickness of the upper surface plate 16, and the thickness of the friction cut member 51. Thereby, in the state where the fixing bolt 10 is fastened, the upper end surface of the fixing bolt 10 is substantially the same surface as the upper surface of the friction cut member 51, so that there is no obstacle when the box-shaped pipe member 52 is press-fitted. Moreover, it becomes possible to avoid that the inner bolt hole 12 and the outer bolt hole 11 are clogged with earth and sand. In FIG. 2, a female screw for screwing the fixing bolt 10 is provided only in the outer bolt hole 11, but a female screw may be provided in both the inner bolt hole 12 and the outer bolt hole 11. .

  In this embodiment, when the box-shaped pipe member 52 is press-fitted into the ground, as shown in FIGS. 3 (a) and 3 (b), the fixing bolt 10 at the location where the injected solidifying material is injected is connected to the inner bolt hole 12 and Remove from the outer bolt hole 11, replace the injection jig 13, and connect the injection hose 24 via the connection joint 21, and then inject the solidified material from the inside of the box-shaped pipe member 52 to the ground outside the friction cut member 51. It is possible to stabilize the ground outside the friction cut member 51 by pumping and injecting.

  For example, due to the presence of an unexpected cobblestone or a hard ground, the ground outside the cross section of the box-shaped pipe member 52 is shaved, and as shown in FIG. When the presence of a loosened portion 19 is expected, the void 19 or the loosened portion 19 is used as an injection solid material injection point, and only the fixing bolt 10 disposed at the injection point is removed for injection. By replacing the jig 13 and injecting the injected solidified material into the injection location at a short distance from the inside of the box-shaped pipe member 52, the work of filling and solidifying the injected solidified material in the space 19 or the loosened portion 19 can be quickly performed. Thus, the ground outside the friction cut member 51 can be effectively reinforced and stabilized.

  Here, as the infusion solidifying material, various known infusion solidifying materials used in the tunnel method, the ground improvement method, and the like can be used. More specifically, the suspension type grout using ultrafine cement is used. It is preferable to use a material. Suspension-type grout materials can adjust the gel time from a few seconds and have high initial strength, so they can be used in a wide range of applications, from void filling that sets the gel time short to osmotic injection in the ground where the gel time is set long. It becomes possible to respond.

  Further, as the injection jig 13, it is preferable to use an injection jig that includes a valve such as the ball valve 20 or a check valve so that the injected injection solidified material does not flow back to the box-shaped pipe member 52. 5A and 5B illustrate a more specific form of the injection jig 13. The injection jig shown in FIG. 5 (a) is a valve-type injection jig 13a, and is provided with a processing bolt part 30 having a centering process for an injection hole at the center, and this processing bolt. The socket 31 is attached to and detached from the inner bolt hole 12 and the outer bolt hole 11 via the portion 30, and is constituted by a socket 31, a ball valve 32, a coupler joint 33, and the like welded to the processed bolt portion 30. The injection jig shown in FIG. 5B is a socket-type injection jig 13b, and has a processing bolt part 30 with a centering process for an injection hole at the center, and this processing bolt. The socket 30 is attached to and detached from the inner bolt hole 12 and the outer bolt hole 11 via the portion 30, and is constituted by a socket 31 welded to the processed bolt portion, a coupler joint 33, and the like.

  And according to this embodiment, the injection solidification material is injected from the inner side of the box-shaped pipe member 52 to the ground outside the friction cut member 51 via the injection jig 13 attached to the inner bolt hole 12 and the outer bolt hole 11. For example, as shown in FIG. 6, the operation of pumping and injecting can be performed for each box-shaped pipe member 52 that is press-fitted. By performing the operation of injecting the injection solidifying material for each box-shaped pipe member 52, the ground outside the friction cut member 51 can be stabilized at an early stage. Since the width of each box-shaped pipe member 52 is as narrow as about 800 mm, even if a gap or loosening of the ground occurs, there is little influence on the upper ground, so each box-shaped pipe member 52 is injected for each box-shaped pipe member 52. By performing the work, it is possible to almost eliminate the influence on the existing railroad tracks and roads above.

  If there are a plurality of locations where the injection solidifying material is injected into the box-shaped pipe member 52, all the fixing bolts 10 at the locations to be injected are removed and replaced with the injection jig 13, and then each injection jig 13 is replaced. It is preferable to connect the injection hose 18 to the pressure and feed the injected solidified material. Thus, when the fixing bolt 10 is removed and replaced with the injection jig 13, the injection solidified material injected at other injection locations is prevented from leaking through the inner bolt hole 12 and the outer bolt hole 11. Is possible.

  In addition, in the wellhead portion of the starting shaft 53 or the reaching shaft 54, as shown in FIG. 7, by filling the gap between the earth retaining wall 21 and the friction cut member 51 with, for example, the filling mortar 22 for closing, It is preferable to close it. By closing the gap between the retaining wall 21 and the friction cut member 51, it is possible to avoid injection of the solidified material injected and injected into the ground outside the friction cut member 51 into the shafts 53 and 54. It becomes possible to do.

  Furthermore, according to the present embodiment, for example, when the ground outside the friction cut member 51 is a hard ground, the box-shaped pipe is inserted through the inner bolt hole 12 and the injection jig 13 attached to the outer bolt hole 11. For example, as shown in FIG. 8, a plurality of box-shaped pipe members 52 are press-fitted and then the plurality of the pipe-shaped pipe members 52 are pressed and injected from the inside of the member 52 to the ground outside the friction cut member 51. The box-shaped pipe member 52 can be collectively performed. As a result, it is possible to inject a considerable amount of the injected solidified material in a single operation, and to improve the efficiency of the work process and the injected solidified material to be used.

  Then, according to the construction method of the underpass of the present embodiment as described above, the injection solidified material can be easily and quickly applied to the ground outside the friction cut member 51 attached to the box-shaped pipe member 52 constituting the pipe roof 55. It is possible to construct the underpass in a more stable state. That is, according to the present embodiment, the friction cut member 51 and the box-shaped pipe member 52 are fixed and released from being fixed to the plurality of inner bolt holes 12 formed in the box-shaped pipe member 52 and the friction cut member 51. The plurality of outer bolt holes 11 are matched to each other, and the fixing bolt 10 screwed and fastened is attached and detached, and these matched inner bolt holes 12 and outer bolt holes 11 are injected. It is possible to easily inject the injection solidified material at a short distance from the inside of the box-shaped pipe member 52 to the ground outside the friction cut member 51 through the injection jig 13 replaced with the hole. Become. Therefore, compared with the case where the injection solidified material is injected through the boring hole formed by boring a hole from the starting shaft 53 or the reaching shaft 54, the injection solidifying material is injected into the predetermined injection location very easily. As a result, it becomes possible to respond quickly to gaps and loosening of the ground, so it is possible to build an underpass while stabilizing the ground outside the friction cut member 51 more firmly. Become.

  The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, it is not always necessary to bring the end face of the underground passage outline structure into contact with the end face of the pipe roof with an intermediate push jack interposed therebetween, and the end face of the underground passage outline structure can also be brought into direct contact with the end face of the pipe roof. In addition, the underpass outer structure may be pushed and pushed from the starting shaft, or may be pushed and pushed from the reaching shaft. Furthermore, when the box-shaped pipe member to which the friction cut member is fixed is also disposed on the side wall portion of the planned underpass, the present invention is applied to inject the solidified material into the ground outside the friction cut member of the side wall portion. You can also

It is sectional drawing explaining the structure of the box-shaped pipe member press-fitted in a parallel state in the construction method of the underpass which concerns on preferable one Embodiment of this invention. It is the A section expanded sectional view of Drawing 1 explaining the fixed state of a box-shaped pipe member and a friction cut member. (A), (b) is the A section enlarged sectional view of Drawing 1 explaining the state where an injection jig is changed by changing an injection jig into an inner bolt hole and an outer bolt hole. It is a longitudinal cross-sectional view explaining the location which inject | pours an injection | pouring solidification material into the ground of the outer side of a friction cut member. (A), (b) is explanatory drawing which illustrates the more concrete shape of the jig | tool for injection | pouring. It is explanatory drawing of the condition which performs the operation | work which supplies injection | pouring solidification material to the ground outside a friction cut member for every box-shaped pipe member. It is explanatory drawing of the state which obstruct | occluded the clearance gap between the earth retaining wall of a shaft, and a friction cut member with the filling mortar. It is explanatory drawing of the condition which performs the operation | work which supplies an injection | pouring solidification material to the ground outside a friction cut member collectively with respect to several box-shaped pipe members. (A)-(j) demonstrates the process of the construction method of the underground passage which forms an underground passage by replacing the pipe roof formed in the ground with the underground passage outline structure with the friction cut member remaining in the ground. It is a longitudinal cross-sectional view and a cross-sectional view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Fixing bolt 11 Outer bolt hole 12 Inner bolt hole 13 Injection jigs 14a and 14b Side plate 15a Outer guide rib 15b Inner guide rib 16 Top plate 17 Lap plate 18 Washer 19 Where to inject)
20 Ball valve 21 Connecting joint 22 Filling mortar 23 Connecting plate 24 Injection hose 50 Planned underground passage 50a Upper floor position 51 of the planned underground passage Friction cut member 52 Box-shaped pipe member 53 Starting shaft 54 Reaching shaft 55 Pipe roof 56 Underpass structure 56a Upper floor portion 57 of underpass outer structure 57 Middle push jack 58 Former push jack 59 Cutting edge member 60 Underpass

Claims (4)

A plurality of box-shaped pipe members having a friction cut member fixed to a surface arranged along the outer periphery of the planned underground passage having a rectangular cross section are press-fitted in parallel into at least the upper floor position of the planned underground passage, After the pipe roof penetrating the planned underground passage is formed in the ground, at least the end surface of the upper floor portion of the underground passage having a rectangular cross section is brought into contact with the end surface of the pipe roof, and the inner end of the underground passage outer structure The pipe roof at least in the upper floor position is left in the ground with the friction cut member released from being fixed to the box-shaped pipe member by propelling the underpass outer structure while excavating the sand and sand on the face of In the method of constructing an underpass that forms an underpass with the underpass structure in the planned underpass by replacing the underpass with the underpass structure. Te,
The fixation and release of the friction cut member and the box-shaped pipe member match each of a plurality of inner bolt holes formed in the box-shaped pipe member and a plurality of outer bolt holes formed in the friction cut member. It is done by attaching and detaching the fixing bolt that is screwed and tightened,
When the box-shaped pipe member is press-fitted into the ground, the fixing bolt at the location where the injection solidifying material is injected is removed from the inner bolt hole and the outer bolt hole, and the injection jig is replaced. A method for constructing an underpass characterized by stabilizing the ground outside the friction cut member by injecting a solidified material into the ground outside the friction cut member from the inside of the box-shaped pipe member.   The fixing bolt is screwed and fastened to the inner bolt hole and the outer bolt hole in a state where the position of the tip of the fixing bolt substantially matches the outer opening surface of the outer bolt hole formed in the friction cut member. The method for constructing an underpass according to claim 1, wherein the underpass is constructed.   The operation of injecting the injection solidifying material into the ground outside the friction cut member from the inside of the box-shaped pipe member through the injection jig attached to the inner bolt hole and the outer bolt hole is carried out one by one. The construction method of the underpass of Claim 1 or 2 performed for every said box-shaped pipe member. The operation of injecting the injection solidifying material into the ground outside the friction cut member from the inside of the box-shaped pipe member through the injection jig attached to the inner bolt hole and the outer bolt hole is a plurality of the box shapes. The method for constructing an underground passage according to claim 1 or 2, wherein the pipe member is press-fitted and then collectively performed on the plurality of box-shaped pipe members.

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