Method for constructing underground structure

Abstract

The present invention provides a method for constructing an underground structure in which a box-shaped roof is assembled and placed so as to correspond to the outer shape of a concrete box body to be propelled and then press-fitted into the ground from a start pit, after which a leading-end part of the concrete box body is placed at an end part of the box-shaped roof, and sediment on the face is pushed out together with the box-shaped roof as the concrete box body is towed. With this method, the concrete box body can be towed and propelled safely even in places where it is not possible to provide a sufficient reaction force body in front of the concrete box body to be towed.　A propulsion body panel for receiving reaction force is installed behind a floor plate of the concrete box body, and a tow cable, one end of which is fastened to a side wall of a front bitt of the floor plate of the concrete box body, is laid out on the floor plate portion of the concrete box body and made to penetrate inside the propulsion body panel for receiving reaction force. The other end of the tow cable is anchored to a towing jack installed on a lateral surface of the propulsion body panel for receiving reaction force. The concrete box body tows the tow cable by means of the towing jack, and this towing pushes out the propulsion body panel for receiving reaction force together with the concrete box body.

Description

Underground structure construction method

[0001] The present invention relates to a method for constructing underground structures that allows for the construction of large-width underground structures by excavating them transversely beneath the ground, such as railways and roads, without interfering with traffic above.

[0002] Excavating large underground structures transversely beneath railways, roads, and other structures requires protective measures to support traffic above, such as installing a pipe roof in which steel pipes are laid out horizontally.

[0003] However, because the pipe roof was first constructed as a separate project, and then excavation was carried out to build the underground structure, and the underground structure was excavated underneath the pipe roof, the soil cover became thicker due to the presence of the pipe roof. Moreover, the protective work for the pipe roof construction was carried out separately from the main work of burying the underground structure, which increased the construction costs and time.

[0004] To solve this problem, a construction method for underground structures has been proposed, as shown in the following Patent Document 1, in which a box-shaped roof, which is a cylindrical roof body, is arranged, and the box-shaped roof that has reached the access tunnel is successively removed by alternately repeating the advancement of the box-shaped roof and the advancement of the concrete box body.Furthermore, this method has been further developed to solve the following drawbacks of Patent Document 1, and the following Patent Documents 2 and 3 have been filed and obtained as patents.Japanese Patent Publication No. 55-19312Japanese Patent No. 3887383Japanese Patent No. 4317843

[0005] The drawbacks of Patent Document 1 are as follows: i) Because the box roofs are advanced one by one, it takes time and effort to advance all of the box roofs. ii) After the box roofs are advanced, the face is excavated before the concrete box body is advanced. Therefore, a process of excavating the face is inserted between the advancement of the box roofs and the advancement of the concrete box body, and excavation work was required as a separate operation from the advancement of the concrete box body 9. This not only increases construction costs but also extends the construction period accordingly. iii) Excavation work at the face is accompanied by the risk of the face collapsing, and ground improvement work such as stabilization work to stabilize the face is also required.

[0006] In Patent Documents 2 and 3, when the concrete box body is advanced after the box roof is pressed in, the soil at the face is pushed out along with the box roof as the concrete box is advanced, so there is no need to perform additional excavation work at the face, which reduces costs and shortens the construction period.In addition, safety is improved by eliminating the dangerous excavation work at the face, and further, by distributing the reaction force resistance for advancing the concrete box, large-scale equipment is not required.

[0007] The invention of Patent Document 2 involves disposing a push jack and struts as propulsion equipment between the concrete box and the reaction wall at the rear, and extending the push jack to push the concrete box forward, while the invention of Patent Document 3 involves pushing the concrete box forward by towing.

[0008] Compared to the invention of Patent Document 2, in which the concrete box is pushed out by a push jack, the invention of Patent Document 3, in which the concrete box is pushed out by towing, has the advantage that the concrete box can be pushed out a long distance and stably without being affected by the stroke of the push jack.

[0009] In the invention of Patent Document 3, as shown in Figure 35, a starting tunnel 3 and an arrival tunnel 4 are constructed using earth-retaining steel sheet piles 2, and a box-shaped roof 6 is arranged in a square shape to correspond to the outer shape of a concrete box body 9. In this case, a friction cutter plate 7 is placed on the side of the ground, and can separate the box-shaped roof 6 and concrete box body 9 from the surrounding soil and sand.

[0010] In the figure, 17 is a belly-raising material, and 19 is a retaining member. The retaining member 19 can be used by cutting out a portion of the retaining steel sheet pile 2 with a mirror cut, and is fixed with a tie rod material 18 that connects the retaining steel sheet pile 2 on the departure tunnel 3 side and the retaining steel sheet pile 2 on the arrival tunnel 4 side.

[0011] A reaction body 21 made of the natural ground is provided on the side of the arrival tunnel 4, and a reaction wall 23 is provided in front of the reaction body 21.

[0012] The concrete box body 9 is propelled by a push jack 10 and a strut 16 disposed behind the concrete box body 9. Reference numeral 20 denotes a launch pad.

[0013] The concrete box 9 is propelled by a towing jack 24 attached to the reaction wall 23, one end of which is attached to a towing cable 25, the other end of which is fixed to an anchoring device 26 attached to the rear of the concrete box 9. A center hole jack can be used as the towing jack 24, and the anchoring device 26, not shown, consists of a cone and an anchoring plate.

[0014] In addition, the towing jack 24 and the anchoring device 26 may be interchanged, with the towing jack 24 attached to the rear of the concrete box body 9, and the other end of the towing cable 25 attached to this towing jack 24 being anchored to the anchoring device 26 fixed to the reaction wall 23.

[0015] The main push jack 10 is extended, and at the same time the traction jack 24 is operated to pull the concrete box body 9 from the starting tunnel 3 toward the arrival tunnel 4 with the traction cable 25, thereby pushing the concrete box body 9 forward.

[0016] The box roof 6 is extruded simultaneously with the extrusion of the concrete box body 9, and furthermore, the face is not excavated, and when the box roof 6 is extruded, the retaining members 19 arranged in the area surrounded by the box roof 6 are simultaneously extruded, thereby extruding the soil 29 in front of them at the same time. In this case, since the friction cutter plate 7 separates the box roof 6 and concrete box body 9 from the surrounding soil and sand, the box roof 6 and concrete box body 9 can be advanced smoothly.

[0017] As the concrete box body 9 advances, a strut 16 is disposed between the concrete box body 9 and the reaction wall 8 at the rear thereof to ensure the thrust length of the main jack 10.

[0018] When the box-shaped roof 6 and the soil and sand extruded simultaneously surrounded by the box-shaped roof 6 reach the arrival pit 4 in this way, the box-shaped roof 6 is removed in the arrival pit 4 and at the same time the soil and sand are excavated and discharged.

[0019] Then, the concrete box 9 is advanced until its tip reaches the arrival hole 4, completing the advancement of the entire length of the concrete box 9.

[0020] According to the invention of Patent Document 3, the soil at the face is pushed out together with the box roof by the front end of the concrete box, so the pushing of the box roof and the pushing and towing of the concrete box can be carried out simultaneously, eliminating the excavation process at the face that was previously required between the processes of pushing the box roof and the concrete box, thereby reducing construction costs and shortening the construction period. In addition, the elimination of dangerous excavation work at the face improves construction safety.

[0021] Furthermore, because the concrete box is pushed and towed, the soil at the face is pushed out along with the box roof, and the reaction resistance for moving the concrete box can be dispersed more effectively than when the concrete box is only pushed or towed, and the reaction force at one location can be smaller. This eliminates the need for auxiliary construction methods such as ground improvement, which are required when the resisting earth pressure is insufficient, and reduces the cost and construction time required for auxiliary construction methods.

[0022] In the invention of the aforementioned Patent Document 2, a reaction body made of the natural ground is provided on the arrival tunnel side to pull the concrete box.

[0023] Building such a reaction body using the natural ground is impossible unless there is sufficient space on the arrival tunnel side, and it requires a large-scale construction project including the installation of a reaction wall. Moreover, the traction cable runs from the reaction body through the box-shaped roof enclosure to the concrete box, which inevitably makes it long and can make the traction operation unstable.

[0024] The object of the present invention is to provide a construction method for underground structures that eliminates the disadvantages of the above-mentioned conventional examples, enables a concrete box to be safely towed and advanced even in places where it is not possible to provide a sufficient reaction force body in front of the concrete box to be towed, and because the soil at the face is pushed out by the tip of the concrete box together with the box-shaped roof, the advancement of the box-shaped roof and the advancement and advancement of the concrete box can be carried out simultaneously, eliminating the excavation process at the face that was previously required during the concrete box advancement process, reducing construction costs and shortening the construction period, and improving construction safety by eliminating the dangerous excavation work at the face.

[0025] In order to achieve the above-mentioned object, the invention described in claim 1 is a construction method for underground structures in which a box-shaped roof is assembled and positioned to correspond to the outer shape of the concrete box to be pushed, and then it is pressed into the ground from the starting tunnel.After that, the tip of the concrete box is placed on the end of the box-shaped roof, and the concrete box is pulled and the soil at the face is pushed out together with the box-shaped roof.In this method, a reaction force receiving thruster panel is installed behind the floor plate of the concrete box, and a traction cable with one end attached to the front bit side wall of the floor plate of the concrete box is arranged in the floor plate part of the concrete box and passed through the reaction force receiving thruster panel, and the other end of this traction cable is fixed to a traction jack installed on the side of the reaction force receiving thruster, and the concrete box is pulled by the traction cable with the traction jack, and the reaction force receiving thruster panel is pushed out together with the concrete box by this pulling.

[0026] According to the present invention, a reaction force receiving thrust plate is installed behind the floor plate of the concrete box, and the concrete box and the reaction force receiving thrust plate are towed together with a towing jack, so there is no need to install a reaction force body in the ground on the front side of the concrete box on the arrival hole side. Furthermore, since the towing work can be done entirely behind the concrete box, there is little impact on the surrounding ground, etc., and construction can be carried out safely.

[0027] The present invention as set forth in claim 2 is characterized in that the concrete box is constructed on a launching platform, and the launching platform has raised sides to form side guide concrete for the concrete box.

[0028] According to the present invention as set forth in claim 2, when the concrete box is advanced by towing, it is guided by the side guide concrete provided on the starting platform, so that it can be advanced safely in the proper direction without bending.

[0029] The present invention as described in claim 3 is characterized in that the traction cable is arranged in the floor panel portion of the concrete box by embedding a traction cable insertion box in the concrete box when the concrete box is constructed and inserting the traction cable into the traction cable insertion box.

[0030] According to the present invention described in claim 3, a traction cable, one end of which is anchored to the front bit side wall of the floor plate of the concrete box, can be arranged in the floor plate portion of the concrete box reliably and safely by embedding a traction cable insertion box in the concrete box when the concrete box is constructed and inserting the traction cable into the traction cable insertion box.

[0031] The fourth aspect of the present invention is characterized in that the traction cable insertion box comprises an upper cover that moves together with the concrete box body and a main body to which the upper cover is fitted.

[0032] According to the present invention as set forth in claim 4, the traction cable is passed through the traction cable insertion box and arranged in the floor panel portion of the concrete box, but the top cover of the traction cable insertion box moves together with the concrete box, while the main body remains, so that the concrete box can be moved without dragging the traction cable.

[0033] The present invention as set forth in claim 5 is characterized in that a lubricant injection device is installed inside the concrete box, and lubricant is injected into the bottom of the concrete box by the lubricant injection device when the concrete box is moved forward.

[0034] According to the present invention as set forth in claim 5, by injecting a lubricant into the bottom of the concrete box when the concrete box is moved forward, the frictional resistance of the concrete box when it is moved forward can be reduced, allowing it to be pulled smoothly.

[0035] As described above, the construction method for underground structures of the present invention allows the concrete box to be safely towed and advanced even in places where it is not possible to provide a sufficient reaction force body in front of the concrete box to be towed, and because the soil and sand at the face are pushed out together with the box-shaped roof by the tip of the concrete box, the advancement of the box-shaped roof and the advancement and advancement of the concrete box can be carried out simultaneously, eliminating the excavation process at the face that was previously required during the concrete box advancement process, thereby reducing construction costs and shortening the construction period, and improving construction safety by eliminating the dangerous excavation work at the face.

[0036]

[0023] FIG. 1 is a longitudinal side view showing a first step of the construction method for an underground structure of the present invention.

[0024] FIG. 2 is a plan view showing a first step of the construction method for an underground structure of the present invention.

[0025] FIG. 3 is a longitudinal side view showing a first step of the construction method for an underground structure of the present invention.

[0026] FIG. 4 is a plan view showing a second step of the construction method for an underground structure of the present invention.

[0027] FIG. 5 is a longitudinal side view showing a third step of the construction method for an underground structure of the present invention.

[0028] FIG. 6 is a plan view showing a fourth step of the construction method for an underground structure of the present invention.

[0029] FIG. 7 is a longitudinal side view showing a seventh step of the construction method for an underground structure of the present invention.

[0029] FIG. 8 is a plan view showing a eighth step of the construction method for an underground structure of the present invention.

[0029] FIG. 9 is a longitudinal side view showing a ninth step of the construction method for an underground structure of the present invention. 1. A plan view showing the ninth step of the construction method for an underground structure of the present invention. 2. A longitudinal side view showing the tenth step of the construction method for an underground structure of the present invention. 3. A plan view showing the tenth step of the construction method for an underground structure of the present invention. 4. A longitudinal side view showing the eleventh step of the construction method for an underground structure of the present invention. 5. A plan view showing the eleventh step of the construction method for an underground structure of the present invention. 6. A longitudinal side view showing the twelfth step of the construction method for an underground structure of the present invention. 7. A plan view showing the twelfth step of the construction method for an underground structure of the present invention. 8. A longitudinal side view showing the thirteenth step of the construction method for an underground structure of the present invention. 9. A longitudinal side view showing the fourteenth step of the construction method for an underground structure of the present invention. 10. A longitudinal side view showing the fourteenth step of the construction method for an underground structure of the present invention. 11. A plan view showing the tenth step of the construction method for an underground structure of the present invention. 12. A longitudinal side view showing the thirteenth step of the construction method for an underground structure of the present invention. 13. A longitudinal side view showing the fourteenth step of the construction method for an underground structure of the present invention. 14. A longitudinal side view showing the fifteenth step of the construction method for an underground structure of the present invention. 15. A cross-sectional view taken along line A-A in FIG. 10. 16. A cross-sectional view taken along line A-A in FIG. 12. 17. A detailed view of part a in FIG. 13. 18. A cross-sectional view taken along line B-B in FIG. 14. 19. A longitudinal side view showing a conventional example.

[0037] The following describes in detail an embodiment of the present invention with reference to the drawings. Figures 1 to 30 are longitudinal side views and plan views of each step of the construction method for underground structures of the present invention, and the same components as those in the conventional example shown in Figure 35 are given the same reference numerals.

[0038] First, let me explain the equipment. In the figure, reference numeral 2 denotes a retaining steel sheet pile, which uses sheet piles, H-shaped steel, etc. This retaining steel sheet pile 2 is used to construct a starting tunnel 3 and a reaching tunnel 4.

[0039] In the figure, reference numeral 6 denotes a box-shaped roof, which is a box-shaped cylindrical body with a roughly square cross section, with hook-shaped joints formed continuously in the longitudinal direction on the side, and a friction cutter plate 7 superimposed on the top surface or side.

[0040] This box-shaped roof 6 has connecting flanges at the front and rear ends, and can be connected lengthwise by bolting in order to bury the required length, and further connected in parallel in the vertical and horizontal directions via hook-shaped joints.

[0041] The box-shaped roof 6 is arranged in a square shape to correspond to the outer shape of the concrete box body 9. At this time, the friction cutter plate 7 is arranged on the side of the ground, and can separate the box-shaped roof 6 and the concrete box body 9 from the surrounding soil and sand.

[0042] The concrete box 9 is a reinforced concrete structure that forms the underground structure to be constructed, and is a cylindrical box culvert consisting of a floor plate 9a, a top plate, and left and right side plates.

[0043] In the figure, reference numeral 20 denotes a launch pad formed by pouring concrete, and the concrete box 9 is constructed on this launch pad 20. The launch pad 20 has raised sides to form side guide concrete 20a to the concrete box.

[0044] In the figure, reference numeral 30 denotes a reaction force receiving thruster plate installed behind the floor plate 9a of the concrete box 9. It is constructed from reinforced concrete, with its front end formed as a vertical surface that abuts against the concrete box 9 and its rear end formed as an inclined surface for mounting the towing jack 24. A plurality of reaction force receiving thruster plates 30 are installed side by side with intervals between them.

[0045] The towing jack 24 is a center-hole type jack that pulls the towing cable 25. Although not shown, it has a wedge-shaped cone and a fixing plate.

[0046] As shown in Figures 3 and 4, a retaining steel sheet pile 2 is driven beside an overhead transportation 31 such as a railway to construct a starting tunnel 3 and an arrival tunnel 4, a platform 32 is assembled in the starting tunnel 3, a box-shaped roof 6 is placed on top of it, and the box-shaped roof 6 is passed through the opening of the retaining steel sheet pile 2 in a mirror-opening manner and pressed from the starting tunnel 3 to the arrival tunnel 4.

[0047] The box-shaped roof 6 is pressed into place by providing a propulsion jack 33, a spacer 34, and a strut 35, and a worker inside the box-shaped roof 6 manually excavates using the tip cutting edge, and the excavated soil is sent rearward using a cart, and the box-shaped roof 6 is pushed forward by the propulsion jack 33 in the amount of excavation.

[0048] A friction cutter plate 7 is attached to the top surface of a box-shaped roof 6, which is a cylindrical roof body, in the same manner as in the conventional case, and is extruded together with the box-shaped roof 6.

[0049] Once the box-shaped roof 6 for the upper floor portion is in place, the platform 32 is removed, and then the box-shaped roof 6 for the lower floor portion is in place, followed by the box-shaped roofs 6 for the left and right wall portions, with the box-shaped roofs 6 being arranged in a square shape to correspond to the outer shape of the concrete box 9 to be pushed forward.

[0050] The interior of the rectangular box roof 6 contains earth and sand, and the parts obtained by mirror cutting a part of the earth-retaining steel sheet pile 2 at the front and rear can be used as earth-retaining members 19. The front and rear earth-retaining members 19 may be fixed to each other with tie rods.

[0051] The retaining members 19 and the box-shaped roof 6 are fixed together with temporary fastening members 27. A pit 36 ​​is constructed in the starting tunnel 3 directly below the rear end of the box-shaped roof 6 to secure the towing members. Crushed stone is laid on the bottom of the starting tunnel 3, and concrete is poured on top of it to construct the starting platform 20 (see Figures 9 and 10).

[0052] As mentioned above, the starting platform 20 has raised sides to form side guide concrete 20a to the concrete box body, and guide plates 37 made of strip-shaped steel plates are laid on the inside of this side guide concrete 20a.

[0053] The concrete box 9 is constructed on the launch platform 20 of the launch tunnel 3. When constructing this concrete box 9, one end of the traction cable 25 is anchored to the side wall of the bit 36 ​​in front of the floor plate 9a of the concrete box 9 with a fixing device, and the traction cable 25 is stretched and disposed in the floor plate 9a portion of the concrete box 9. Note that in order to pass the traction cable 25 from the side wall of the bit 36 ​​through the launch platform 20 and pull it out to the top surface of the launch platform 20, a sheath pipe 46 is buried in the launch platform 20 and the traction cable is inserted through it.

[0054] The traction cable 25 is arranged on the floor plate 9a of the concrete box 9 by embedding a traction cable insertion box 38 in the concrete box 9 when the concrete box 9 is constructed, and inserting the traction cable into the traction cable insertion box 38.

[0055] The traction cable insertion box 38 consists of an upper cover 38a that moves with the concrete box body 9 and a main body 38b to which the upper cover 38a fits. The upper cover 38a has dowel bars 39 provided as protrusions at appropriate intervals, which act as stud dowels to maintain the unity with the floor plate 9a of the concrete box body 9.

[0056] Before constructing the concrete box 9, a lubricant was applied to the upper surface of the launch pad 20 and an insulating sheet was installed, and the lubricant and insulating sheet 40 were laid between the traction cable insertion boxes 38.

[0057] When constructing the concrete box 9, steel plates 41 for pushing the box are arranged in strips at intervals between the traction cable insertion boxes 38, avoiding the positions where lubricants are injected onto the steel plates with the dowel bars 39 arranged at appropriate intervals above them, and the steel plates are laid side by side at intervals between the traction cable insertion boxes 38. By constructing the concrete box 9 on top of these, the concrete box 9 includes the steel plates 41 for pushing the box on its bottom (see Figure 18).

[0058] As shown in Figures 19 and 20, a reaction force receiving thrust body panel 30 is constructed behind the floor plate 9a of the concrete box body 9, and a traction cable 25 arranged in the floor plate 9a portion of the concrete box body 9 is extended to pass through the reaction force receiving thrust body panel 30, and then inserted into a traction jack 24 provided on the reaction force receiving thrust body panel 30 to secure it in place.

[0059] Additionally, connecting steel members 42, each consisting of a square frame of H-shaped steel beams, are arranged on the front end face of the concrete box 9. Furthermore, a lubricant injection device 43 is installed on the floor plate 9a within the concrete box 9, and a lubricant injection pipe 44 is pre-placed in the floor plate 9a so as to pass vertically through it and exit to the bottom.

[0060] The towing jack 24 is operated to push the concrete box 9 forward via the reaction force receiving propulsion body plate 30. (Impermanent pushing) At this time, lubricant is injected into the bottom of the concrete box 9 from the lubricant injection device 43.

[0061] The concrete box body 9 and the box-shaped roof 6 are connected via the connecting steel material 42, and the friction cutter plate fixing beams 45 connect the friction cutter plates 7 arranged on the top, sides, and bottom of the concrete box body 9 to the friction cutter plates 7 installed on the box-shaped roof 6.

[0062] This friction cutter plate 7 separates the box-shaped roof 6 and concrete box body 9 from the surrounding soil and sand.

[0063] The traction jack 24 is operated to pull the reaction force receiving propulsion body 30 and the concrete box 9 with the traction cable 25 from the departure tunnel 3 toward the arrival tunnel 4, thereby pushing the concrete box 9 forward.

[0064] The box-shaped roof 6 is extruded simultaneously with the extrusion of the concrete box body 9, and furthermore, the face part is not excavated, and when the box-shaped roof 6 is extruded, the earth retaining member 19 arranged in the part surrounded by the box-shaped roof 6 is extruded at the same time.

[0065] In this case, since the friction cutter plate 7 separates the box-shaped roof 6 and concrete box body 9 from the surrounding soil and sand, the box-shaped roof 6 and concrete box body 9 can be advanced smoothly.

[0066] When the box-shaped roof 6 and the soil 29 extruded simultaneously surrounded by the box-shaped roof 6 reach the arrival pit 4 in this way, the box-shaped roof 6 is removed in the arrival pit 4 and at the same time the soil 29 is excavated and discharged.

[0067] The concrete box 9 is then advanced until its tip reaches the arrival pit 4, completing the entire length of the concrete box 9 (see Figures 29 and 30). If there is another box to be advanced, the reaction force-receiving thruster plate is returned to the back of the starting shaft, and the steps from Figure 16 to Figure 27 are repeated.

[0068] 2 Retaining steel sheet pile 3 Launch tunnel 4 Arrival tunnel 6 Box roof 7 Friction cutter plate 8 Reaction wall 9 Concrete box body 9a Floor plate 10 Base push jack 14 Stop member 16 Strut 17 Waist raising material 18 Tie rod material 19 Retaining member 20 Launch platform 20a Side guide concrete 21 Reaction body 23 Reaction wall 24 Traction jack 25 Traction cable 26 Anchorage device 27 Temporary fastening member 29 Soil 30 Reaction-receiving thrust body base 31 Upper access 32 Frame 33 Push-in jack 34 Spacer 35 Strut 36 Pit 37 Guide plate 38 Traction cable insertion box 38a Top cover 38b Main body 39 Dowel bar 40 Lubricant and edge-cutting sheet 41 Steel plate for box body propulsion 42 Connecting steel material 43 Lubricant injection device 44 Lubricant injection pipe 45 Friction cutter plate fixing girder 46 Sheath pipe

Claims

1. A method for constructing underground structures in which a box-shaped roof is assembled and positioned to correspond to the outer shape of the concrete box to be pushed, and then pressed into the ground from the starting tunnel. After that, the tip of the concrete box is placed on the end of the box-shaped roof, and the soil at the face is pushed out together with the box-shaped roof as the concrete box is pulled. In this method for constructing underground structures, a reaction force receiving thruster panel is installed behind the floor plate of the concrete box, and a traction cable with one end attached to the front bit side wall of the floor plate of the concrete box is arranged in the floor plate part of the concrete box and passed through the reaction force receiving thruster panel, and the other end of this traction cable is fixed to a traction jack installed on the side of the reaction force receiving thruster, and the concrete box is pulled by the traction jack, and the reaction force receiving thruster panel is pushed out together with the concrete box by this pulling.

2. A method for constructing an underground structure according to claim 1, wherein the concrete box is constructed on a launching platform, and the launching platform has raised sides to form side guide concrete for the concrete box.

3. The method for constructing an underground structure according to claim 1, wherein the traction cable is placed in the floor plate portion of the concrete box by embedding a traction cable insertion box in the concrete box during construction and passing the traction cable through the traction cable insertion box.

4. A method for constructing an underground structure according to claim 3, wherein the traction cable insertion box comprises a top cover which moves together with the concrete box body and a main body to which the top cover is fitted.

5. A method for constructing an underground structure according to claim 1, in which a lubricant injection device is installed inside the concrete box, and lubricant is injected into the bottom of the concrete box by the lubricant injection device when the concrete box is advanced.

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