JP2010043454A - Underground-structure construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a construction method excellent in work characteristics and safety without requiring excavation and placement of concrete when constructing an underground structure below a vehicle travelling road. <P>SOLUTION: According to the construction method, a box body 21 is placed in the natural ground below the vehicle travelling road for constructing the underground structure. An upper- and a lower-steel plates and a pair of side-wall steel plates, wherein at least the lower steel plate and the pair of side-wall steel plates are composed of a double-layer of an inner steel plate 8 respectively and outer steel plate 9, are inserted in the natural ground between the start side 2 and the arrival side 3 of the box body 21 in such a way as to form the same outer shape as the box body 21. Next, the space defined between the start-side ends of the respective inner steel plates 8 is closed with an end earth retaining plate 26, and then the respective inner steel plates 8 are pulled out from the arrival side, so as to discharge the sediment surrounded by the respective inner steel plates 8 as a clod 27. Then, the box body 21 is inserted into the portion where the clod 27 is discharged. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an underground structure construction method, and more particularly, to a construction method for constructing an underground structure that crosses the traveling road on the ground below a vehicle traveling road such as a railroad track or a road.

  The COMPASS method is known as one of methods for constructing a cross section structure (tunnel) under a track with a small cross section. This method was developed by the applicants of this application. The ground is cut with a wire saw along the outer shape of the planned structure, a protective steel plate is inserted from the back, and then surrounded by the protective steel plate. This is a construction method in which a supporting work is built while excavating the inside earth and sand using a blade, and concrete is placed by involving the supporting work. Details of this construction method, that is, ground cutting and insertion of the protective steel plate are described in Patent Documents 1 and 2, and excavation after insertion of the protective steel plate is described in Patent Document 3.

  The protective steel plate has a thickness of about 22 mm. Therefore, the above-mentioned method of protecting the natural ground by inserting such a protective steel plate does not cause the natural ground deformation and thus the rail line deformation, and the earth covering is reduced to increase the freedom of tunnel design. There is a great advantage that you can.

  However, the following problems can be pointed out. In other words, the above construction method requires excavation work of the inner soil mass in a narrow space surrounded by protective steel plates and placement work of high-fluidity concrete in the closed space, and the construction efficiency is poor and the construction management is less than that of the light section. There is a problem of difficulty.

  In Patent Document 4, two steel plates are overlapped and inserted into a natural ground, and a box installed on the starting side is pulled from the arrival side to discharge each inner steel plate and the earth and sand surrounded by it to the arrival side. At the same time, a method for inserting the box into the ground is disclosed. However, in this conventional method, the inner steel plate is pushed out from behind by the box, so that the inner steel plate may be bent and deformed. For this reason, not only the directionality of each inner steel plate becomes unstable, but the surrounding natural ground may be deformed, which may adversely affect the vehicle travel path.

Prior art information relating to the invention of this application includes the following.
JP 2004-204624 A JP 2005-336865 A JP 2005-336866 A JP 2008-38523 A

The present invention has been made based on the technical background as described above, and achieves the following object.
An object of the present invention is to provide a construction method that eliminates the need for excavation work and concrete placing work when constructing an underground structure below a vehicle travel path, is excellent in workability and safety, and can reduce costs. is there.

The present invention employs the following means in order to achieve the above object.
That is, the present invention is a construction method for constructing an underground structure by installing a box in a natural ground below a vehicle traveling path,
On the ground between the start side and the arrival side of the box, there are upper and lower floor steel plates and a pair of side wall steel plates, at least the lower floor steel plate and the pair of side wall steel plates being an inner steel plate and an outer steel plate. After inserting a stack of the same shape as the outer shape of the box,
Closing between the starting side ends of each inner steel plate with a tiling plate, pulling each inner steel plate from the arrival side and extracting it from the natural ground, the earth and sand surrounded by each inner steel plate as a mass Discharge,
In the construction method of an underground structure, the box is inserted into a discharge portion of the soil mass.

  In the above construction method, it is possible to adopt a mode in which the box is inserted into the discharge portion at the same time as discharging the soil mass. Moreover, the aspect inserted in a natural ground can be taken by pulling the box from the arrival side. In this case, the aspect which pulls each said inner steel plate and the said box with the same pulling jack can be taken.

As equipment for towing the inner steel plates and the box, a push wheel having an opening that is reciprocally movable back and forth with respect to the ground surface on the arrival side, and the tow jack for moving the push wheel And installing a pressure receiving member at the rear end of the box on the starting side,
A mode in which an end portion of each inner steel plate is engaged with the front surface of the push ring through the opening of the push ring, and the push ring and the pressure receiving member are connected via a tensile material penetrating a natural ground. Can be taken.

  Moreover, the aspect which installs the supporting member for hold | maintaining each said inner steel plate extracted from the natural ground in the said reach | attainment side can be taken.

  According to the present invention, by extracting each inner steel plate from the two stacked steel plates inserted so as to have the same shape as the outer shape of the box, the earth and sand surrounded by each inner steel plate is discharged as a lump. Since the box is inserted into the soil mass discharge part, excavation work and concrete placing work are completely unnecessary, and the construction and safety of construction of the underground structure can be improved, and the cost can be reduced. Can do.

  Also, since each inner steel plate is pulled out from the ground by pulling from the arrival side, unlike the case where the inner steel plate is pushed out from the rear, bending deformation does not occur, and therefore the directionality of each inner steel plate is stable and reliable. Therefore, it does not adversely affect the surrounding ground and the vehicle running path.

  Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 are construction procedure diagrams showing an embodiment of an underground structure construction method according to the present invention. A start shaft 2 and a reach shaft 3 are installed on both sides of the ground 1 below the track. First, as shown to Fig.1 (a), the steel plates 4-7 are inserted in the natural ground 1 between the starting shaft 2 and the reaching shaft 3. FIG. As shown in FIG. 5, the steel plates 4 to 7 inserted into the natural ground 1 are upper and lower floor steel plates 4 and 5 and a pair of side wall steel plates 6 and 7.

  The upper and lower floor steel plates 4 and 5 and the side wall steel plates 6 and 7 are inserted into the natural ground 1 so as to form a rectangular cross section, specifically, to form the same shape as the outer shape of the box described later. The upper and lower floor steel plates 4, 5 and the side wall steel plates 6, 7 are each composed of two layers of an inner steel plate 8 and an outer steel plate 9, and a lubricant is interposed between the inner steel plate 8 and the outer steel plate 9. ing. The thickness of the steel plates 4 to 7 is about t = 22 mm when two sheets are stacked.

  The steel plates 4 to 7 are sequentially inserted into the natural ground by the method described in Patent Literatures 1 and 2, for example. That is, if the outline is described, a plurality of guide pipes 10 will be installed in a natural ground along the rectangular shape formed with steel plates 4-7. A pulley is accommodated in the guide pipes 10 so as to be movable in the direction of the pipe axis. A wire saw is wound around the pulleys so as to cross the ground 1 between the guide pipes 10. Each steel plate 4-7 is inserted in the cutting part. In addition, in order to avoid complication of drawing about the guide pipe | tube 10, illustration is abbreviate | omitted in the procedure figure after FIG.1 (b).

  After inserting the steel plates 4 to 7 into the natural ground 1, as shown in FIG. 1 (b), the start stand 11 and the reach stand 12 are installed on the start stand 2 and the reach stand 3, respectively. Further, a retaining member 13 is installed on the ground surface on the start shaft 2 side, and the end of each outer steel plate 9 is fixed to the retaining member 13 by a fixing tool 15. Further, between the end portions of the inner steel plates 8 on the start shaft 2 side, the padding plate 26 is fixed and closed by welding or the like. The start shaft 2 and the reach shaft 3 are usually provided with retaining members 13 and 14 to protect the ground surface, and the retaining member 13 fixes the outer steel plate 9 to the ground. To play the role. Similarly, the tiling plate 26 can be used by cutting a part of the retaining member 13.

  A push wheel 16 is installed in the reach shaft 3 as a traction facility so as to be able to reciprocate back and forth with respect to the ground surface. The push ring 16 has an opening 17 having the same shape as the rectangular shape formed by each inner steel plate 8. Each inner steel plate 8 is extended by fixing the extended steel plate 8a by welding or the like. Then, the end of the extended steel plate 8 a is engaged with the front surface of the push wheel 16 by the engagement tool 18 through the opening 17 of the push wheel 16. A plurality of traction jacks 19 for moving the push ring 16 are arranged between the push ring 16 and the earth retaining member 14. The retaining member 14 is provided with an opening 20 for allowing the inner steel plate 8 and a later-described clump to pass through. The traction jack 19 is provided between the outer periphery of the opening 17 of the push ring 16 and the outer periphery of the opening 20 of the retaining member 14. Installed (see also FIG. 6).

  Furthermore, as shown in FIG.2 (c), the some box 21 is installed in the start shaft 2 in series. The box 21 is a well-known thing used for construction of an underground structure, and has a rectangular cross section and is made of concrete. A pressure receiving member 22 is installed at the rear ends of the boxes 21. Then, the push ring 16 and the pressure receiving member 22 are connected by a plurality of tensile materials, for example, a PC steel rod 23. The PC steel bar 23 penetrates the natural ground 1 through the guide tube 10 shown in FIG. 1A, and both ends thereof are fixed to the push ring 16 and the pressure receiving member 22 by the fixing tool 24, respectively. Although not shown, a correction jack for correcting the direction may be installed in the fixing portion of the PC steel bar 23 on the pressure receiving member 22 side.

  Further, a support member 25 is installed in front of the push wheel 16 in the reaching shaft 3. This support member 25 is for holding each inner steel plate 8 extracted from the natural ground 1 in a rectangular shape, and each inner steel plate 8 can enter inside. The above is the towing preparation work, and the towing method will be described below.

  As shown in FIG. 2 (d), the pusher wheel 16 is moved forward by extending the traction jack 19. The inner steel plates 8 are pulled and extracted from the natural ground 1 by the forward movement of the push wheels 16. Accordingly, the earth and sand surrounded by each inner steel plate 8 is discharged as a mass 27 to the reach shaft 3 side. At this time, each inner steel plate 8 comes into contact with each outer steel plate 9 and is pulled in a state where a lubricant is interposed, so that the friction force is small and each inner steel plate 8 can be smoothly extracted.

  Simultaneously with the pulling of each inner steel plate 8, the box 21 is also pulled through the PC steel bar 23, so that the box 21 is inserted into the discharge portion of the earth block 27 surrounded by each outer steel plate 9. At this time, the box body 21 is inserted into the natural ground 1 with the outer periphery being in contact with the outer steel plates 9, so that the frictional force is small and the box 21 can be smoothly inserted into the natural ground 1. When the direction of the box 21 needs to be corrected, the adjustment is performed by the above-described direction correcting traction jack.

  The above is the traction for one stroke of the traction jack 19. After the traction for one stroke, the push wheel 16 is moved backward by operating the traction jack 19 in a shortened manner as shown in FIG. . As a result, each inner steel plate 8 protrudes from the push ring 16, so that a strut 28 is installed between the engagement tool 18 at the tip of the inner steel plate 8 and the push ring 16. By installing this strut 28, it is possible to shorten the setup change time.

  Next, as shown in FIG. 3 (f), the tow jack 19 is again extended by one stroke, the inner steel plates 8 are pulled to discharge the soil mass 27, and the box 21 is inserted into the discharge portion. . Each inner steel plate 8 gradually enters the support member 25 as the extraction length from the natural ground becomes longer, and the support member 25 holds the rectangular shape. Thereafter, as shown in FIG. 4 (g), the extension and shortening operations of the tow jack 19 are repeated, and as shown in FIG. 4 (h), each inner steel plate 8 is completely extracted from the ground 1 and the mass 27 is also completely removed. At the same time, the entire box 21 is inserted into the natural ground 1. Then, the extracted inner steel plates 8 and the lump 27 are removed at any time after the inner steel plates 8 are extracted or in accordance with the length of the reaching shaft 3.

  As described above, according to the present invention, the inner and outer steel plates are extracted from the two stacked steel plates inserted so as to have the same shape as the outer shape of the box. Since the box is inserted into the lump discharge portion, excavation work and concrete placing work are not required at all, and the workability and safety of construction of the underground structure can be improved.

  Also, since each inner steel plate is pulled out from the ground by pulling from the arrival side, unlike the case where the inner steel plate is pushed out from the rear, bending deformation does not occur, and therefore the directionality of each inner steel plate is stable and reliable. Therefore, it does not adversely affect the surrounding ground and the vehicle running path.

The above embodiment is merely an example, and the present invention can take various forms as described below.
(1) In the above embodiment, both the upper and lower floor steel plates and the pair of side wall steel plates are two-layer steel plates. However, one upper floor steel plate may be used depending on the geological condition of the natural ground (for example, clay). In this case, needless to say, only the inner steel plates of the lower floor steel plate and the pair of side wall steel plates are extracted.

  (2) In the above-described embodiment, by pulling each inner steel plate and box, each inner steel plate is extracted from the ground and the mass is discharged, and at the same time, the box is inserted into the ground. Not only this but a box may be inserted in a natural ground by propelling from the starting side.

  (3) In the above embodiment, the box is inserted into the ground at the same time as each inner steel plate is pulled out from the ground, but the surrounding area around the discharge part of the mass is protected by the outer steel plate. Insertion into the mountain is not necessarily simultaneous.

  (4) In the above embodiment, after inserting the steel plate into the natural ground, the extended steel plate is fixed and extended to the inner steel plate on the reaching side, but the length of the steel plate is increased from the beginning and inserted into the natural ground, The required length may be protruded toward the arrival side.

It is a side view which shows embodiment of this invention and shows a construction procedure. It is a side view which shows the construction procedure following FIG. It is a side view which shows the construction procedure following FIG. It is a side view which shows the construction procedure following FIG. It is a front view of the steel plate inserted in the natural ground. It is an AA arrow directional view of FIG.1 (b).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ground mountain 3 Starting shaft 3 Reaching shaft 4 Upper-floor steel plate 5 Lower-floor steel plate 6,7 Side wall steel plate 8 Inner steel plate 8a Extension steel plate 9 Outer steel plate 10 Guide pipe 11, Starting stand 13 Holding member (earth retaining member)
DESCRIPTION OF SYMBOLS 14 Earth retaining member 15 Fixing tool 16 Push ring 17 Opening 18 Engaging tool 19 Traction jack 20 Opening 21 Box 22 Pressure receiving member 23 PC steel rod 25 Support member 26 Tail retaining plate 27 Earth clump 30 Fixing tool

Claims (6)

It is a construction method that builds an underground structure by installing a box in the ground below the vehicle driving path,
On the ground between the start side and the arrival side of the box, there are upper and lower floor steel plates and a pair of side wall steel plates, at least the lower floor steel plate and the pair of side wall steel plates being an inner steel plate and an outer steel plate. After inserting a stack of the same shape as the outer shape of the box,
Closing between the starting side ends of each inner steel plate with a tiling plate, pulling each inner steel plate from the arrival side and extracting it from the natural ground, the earth and sand surrounded by each inner steel plate as a mass Discharge,
A construction method of an underground structure, wherein the box is inserted into a discharge portion of the mass.   A construction method of an underground structure, wherein the box is inserted into the discharge portion at the same time as discharging the mass.   The construction method for an underground structure according to claim 1 or 2, wherein the box is inserted into a natural ground by pulling the box from the arrival side.   4. The underground structure construction method according to claim 3, wherein each of the inner steel plates and the box are pulled by the same pulling jack. As equipment for towing the inner steel plates and the box, a push wheel having an opening that is reciprocally movable back and forth with respect to the ground surface on the arrival side, and the tow jack for moving the push wheel And installing a pressure receiving member at the rear end of the box on the starting side,
The end of each inner steel plate is engaged with the front surface of the push wheel through the opening of the push wheel, and the push wheel and the pressure receiving member are connected to each other via a tensile material penetrating a natural ground. The underground structure construction method according to claim 4, wherein:   The underground structure construction method according to any one of claims 1 to 5, wherein a supporting member for holding each of the inner steel plates extracted from a natural ground is installed on the reaching side.

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