JPH08232575A - Construction method for shield launching base - Google Patents

Abstract

PURPOSE: To construct a shield launching base in a simple construction process and in a small scale ground improvement during the formation of a shield tunnel below the vertical direction of an existing track. CONSTITUTION: A shaft entrance 3a is set at a site close to an existing track 41 in the horizontal direction. A guide member 6 is slantingly installed to a shield tunnel 46 formation scheduled site directed from the shaft entrance 3a. A caisson 50 which forms an inclined shaft inside, is installed and settled until it reaches the tunnel 46 formation scheduled site in such a fashion that the guide member 6 may be guided from the shaft entrance 3a, thereby forming an inclined shaft 3. Bottom concrete is placed to the bottom of the caisson 50, thereby constituting a shield launching base 30.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention is suitable for application when constructing a shield tunnel for a new track, a new road, a new river, etc. in the underground of an existing track, an existing road, or an existing river in service. About the method of constructing a shield starting base.

[0002]

2. Description of the Related Art FIG. 13 is a cross-sectional side view showing an example of a conventional shield starting base under an existing track, and FIG. 14 is XI, XI of FIG.
FIG. 15 is a cross-sectional view taken in the direction of an arrow, FIG. 15 is a cross-sectional side view showing another example of a conventional shield starting base under an existing orbit, and FIG. 16 is XIV, X of FIG.
FIG. 4 is a sectional view taken along the arrow IV. Conventionally, while using the existing tracks (that is, railway tracks, etc.), roads, and ground upstream aisles facilities such as rivers, the new tracks, roads, rivers, etc. In order to pass through the ground downstream passage facility, it may be necessary to construct a shield tunnel, at this time,
Due to problems such as securing land, it may be required to place the shield start base directly under the existing ground upstream passage facility. In such a case, as an example of the conventional method, FIG.
As shown in FIGS. 3 to 14, a vertical shaft 42 is provided adjacent to the existing track 41, and the vertical shaft 4 is provided from the vicinity of the vertical bottom 42a of the vertical shaft 42 to the horizontal shaft 4.
3 is excavated and constructed, and a portion of the horizontal shaft 43 immediately below the existing track 41 is set as a starting base 44 of the shield excavator 45, and excavation of a shield tunnel 46 is started as shown by a dashed line in FIG. Also, as another conventional method,
As shown in FIGS. 15 to 16, a track protective work 47 is constructed under the existing track 41, and the existing track 41 is attached to the track protective work 47.
The vertical shaft 48 is excavated under the existing track 41, and the shield excavator 45 is started with the bottom of the vertical shaft 48 as the starting base 49.

[0003]

However, in the method shown in FIGS. 13 to 14, the excavation process in the direction of arrow A in FIG. 13 for excavating the shaft 42, and the FIG.
3 The excavation process in the direction of arrow B, and the excavation process in the directions of arrows C and C ′ of FIG. 14 for excavating the shield tunnel 46, and the excavation direction need to be changed at least three times. Machines, equipment, etc. are complicated and very time-consuming. Also, the bottom 42 of the shaft 42
When constructing the horizontal shaft 43 from the vicinity of a, the excavation point becomes a large depth and the excavation is performed under high water pressure, so that the entire excavation area (that is, the area having the width W1 shown in FIG. ), It is necessary to stabilize the ground, which requires a huge amount of auxiliary construction methods, for example, a freezing construction method. In addition, in the method shown in FIGS.
The work of constructing the existing track 41 and temporarily receiving the existing track 41 is required separately from the shaft excavation. Especially, when the existing track 41 is a railway line in service, the process is very complicated. Become. Further, the vertical shaft 48 is used to excavate the ground below the temporarily received existing track 41 so as to excavate the ground, so that the foundation part 47a of the track protector 47 that supports the existing track 41 is excavated.
Must be constructed solid so that it will not be shaken by the excavation of the shaft 48. Therefore, it is necessary to form the improved ground 51 for supporting the foundation portion 47a or construct the soil retaining wall 50 to achieve reliable ground stabilization by large-scale ground improvement. Therefore, the present invention, in view of the above circumstances, when forming a new shield tunnel in the basement of the existing ground upstream passage facility, the construction process is simple, it can be constructed by small-scale ground improvement, a method of constructing a shield starting base, It is provided.

[0004]

That is, the invention according to claim 1 of the present invention is an existing ground upstream passage facility (41), (5).
6), in the ground (2) located vertically below (57), the existing ground upstream passage facilities (41), (56), (5)
7) In forming the shield tunnel (46) extending along the line (7), the existing ground upstream passage facility (41), (5)
6) and (57) are horizontally adjacent to the wellhead (3
a) and (4a) are set, and a cylindrical ground support means (90)
Is installed in a diagonal direction from the wellheads (3a) and (4a) toward the planned formation location of the shield tunnel (46), and the ground (2) inside the ground support means (90) is By excavating, the inclined shafts (3) and (4) are formed in such a manner that the well holes (3a) and (4a) are connected to the planned formation locations of the shield tunnel (46), and the inclined shafts (3) and
Place bottom concrete (10) on the bottom of (4),
The shield starting base (30) is constructed and constructed. The invention according to claim 2 of the present invention is characterized in that, in the invention according to claim 1, the existing ground upstream passage facility is an existing track (41). Also,
In the invention according to claim 3 of the present invention, in the invention according to claim 1, the existing ground upstream passage facility is an existing road (5
6) is a feature. The invention according to claim 4 of the present invention is the invention according to claim 1, wherein the existing ground upstream passage facility is an existing river (57).
It is characterized by being. The invention according to claim 5 of the present invention is the invention according to claim 1, wherein the ground support means (90) is the inclined shaft (3),
It is constituted by the earth retaining material (9) arranged around (4). The invention according to claim 6 of the present invention is the existing ground upstream passage facility (41), (5
6), in the ground (2) located vertically below (57), the existing ground upstream passage facilities (41), (56), (5)
7) In forming the shield tunnel (46) extending along the line (7), the existing ground upstream passage facility (41), (5)
6) and (57) are horizontally adjacent to the wellhead (3
a) and (4a) are set, and the guide means (6), (7),
(8) is installed in a diagonal direction from the wellheads (3a), (4a) toward the planned formation location of the shield tunnel (46), and the inclined shaft spaces (50s), (51) are provided inside.
s), (52s) formed caisson (50), (5
1) and (52) reach the planned location of the shield tunnel (46) from the wellheads (3a) and (4a) using the guide means (6), (7) and (8) as guides. The caisson (50), (51), (5)
The bottom concrete (10) is cast on the bottom of 2) to construct the shield starting base (30). The invention according to claim 7 of the present invention is characterized in that, in the invention according to claim 6, the existing ground upstream passage facility is an existing track (41). Also,
In the invention according to claim 8 of the present invention, in the invention according to claim 6, the existing ground upstream passage facility is an existing road (5
6) is a feature. In the invention according to claim 9 of the present invention, in the invention according to claim 6, the existing ground upstream passage facility is an existing river (57).
It is characterized by being. The invention according to claim 10 of the present invention is the invention according to claim 6, wherein the guide means (6), (7), (8) are the caissons (50), (51), (52). ) Is composed of a plurality of columnar members (61) arranged along the outer peripheral shape. The invention according to claim 11 of the present invention is the invention according to claim 6, wherein the guide means (6), (8) are the caissons (50), (5).
1) and (52) are installed in a tubular shape in a shape corresponding to the outer peripheral shape. The invention according to claim 12 of the present invention is the invention according to claim 6, wherein the guide means (7) is the caisson (50),
(51) and (52) are formed in a form excluding the tunnel formation position (5p). The numbers in parentheses () indicate the corresponding elements in the drawings for convenience, and therefore the present description is not limited to the description in the drawings. The same applies to the following action columns.

[0005]

With the above-mentioned structure, the invention according to claim 1 of the present invention functions so that the shield starting base (30) is arranged at the planned formation location of the shield tunnel (46). In the invention according to claim 2 of the present invention, it is not necessary to temporarily receive the existing track (41). In the invention according to claim 3 of the present invention, the existing road (56) need not be temporarily received. In the invention according to claim 4 of the present invention, it is not necessary to temporarily receive the existing river (57). Also,
In the invention according to claim 5 of the present invention, the ground supporting means (90) made of the earth retaining material (9) acts to earth retain the ground around the inclined shaft. In the invention according to claim 6 of the present invention, the caisson (50), (51), (52) is installed so that the inclined shaft space (50s), (51s), (52).
s) acts so as to be directly arranged so as to connect the wellheads (3a) and (4a) to the planned formation location of the shield tunnel (46). In the invention according to claim 7 of the present invention, provisional receiving of the existing track (41) can be dispensed with. The invention according to claim 8 of the present invention is the existing road (5
It is not necessary to receive the temporary reception of 6). In the invention according to claim 9 of the present invention, it is not necessary to temporarily receive the existing river (57). The invention according to claim 10 of the present invention is
Guide means (6), (7), (8) by arranging a plurality of columnar members (61) in a row in the ground (2) and driving them.
Acts to perform the installation of. The invention according to claim 11 of the present invention is the caisson (50), (51),
(52) acts so as to be submerged in the ground (2) surrounded by the guide means (6), (8). The invention according to claim 12 of the present invention is the tunnel formation position 5p.
The guide means (6), (7), (8) act so as not to be placed on the guide.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a plan view of a ground portion of a shield starting base under construction according to an embodiment of the present invention, and FIG.
II, II arrow sectional view, FIG. 3 is a III, III arrow sectional view of FIG.
4 is a sectional view taken along the line IV, IV of FIG. 3, FIG. 5 is a sectional view showing another example of the shield starting base shown in FIG. 4, and FIG. 6 is a shield starting base being constructed by another embodiment of the present invention. FIG. 7 is a plan view of the above-ground portion, FIG. 7 is a plan sectional view of the underground portion of the shield starting base shown in FIG. 6, FIG. 8 is a diagram showing a construction procedure of yet another embodiment of the present invention, and FIG. FIG. 10 shows a construction procedure of another embodiment, FIG. 10 shows a construction procedure of yet another embodiment of the present invention, FIG. 11 shows a construction procedure of yet another embodiment of the present invention, and FIG. It is a figure which shows the construction procedure of another Example of this invention.

In the shield starting area 1, as shown in FIG. 1, an existing track 41 composed of an ascending line 41a and a descending line 41b is provided on a roadbed formed on the ground 2a.
1 are laid as indicated by the alternate long and short dash line in FIG. 1, and platforms 40, 40 are provided as shown in FIG. 2 at the hatched portions on both sides of the existing track 41 shown in FIG. The existing track 41 is a specific example of an existing ground upstream passage facility. The upper ground passage facility is a flow passage through which people and goods circulate on the ground. Specifically,
In addition to the railroad tracks described above, there are roads that automobiles can pass through and rivers through which water flows. Existing track 41
1 and 2 in the ground 2 located vertically below
As shown in FIG. 2, the shield tunnel 46 is planned to be constructed along the existing track 41, that is, with its extension direction substantially aligned with the extension direction of the existing track 41, as shown by the broken line in FIG. Therefore, the line center CT1 of the existing track 41 and the line center CT2 of the shield tunnel 46 are
As shown in FIG. 2, they substantially match.

Further, in the shield starting area 1,
As shown in FIG. 2, the inclined shaft 3 is formed by excavating a predetermined portion of the ground 2a adjacent to the existing track 41 and the shield tunnel 46 to be formed in an oblique direction, and the inclined shaft 3 has its entrance. 3a has a substantially circular shape at a position horizontally adjacent to the existing track 41 as shown in FIG.
As shown in FIGS. 2 and 3, the oblique shaft center CT3 is formed in an oblique columnar shape so as to be orthogonal to the track center CT1 of the existing track 41 and to have a predetermined gradient α. In addition, inclined shaft 3
Is shaped so that the cross-sectional shape formed in the direction orthogonal to the inclined shaft axis CT3 is circular, so the plane shape of the wellhead 3a is slightly oval as shown in FIG.

Around the inclined shaft 3, as shown in FIGS. 1 to 3, a side wall 5 made of concrete, which is an open type caisson 50 having an inclined space 50s formed therein, is submerged in the ground 2, It is provided in the shape of an inclined cylinder having a predetermined winding thickness, and further, around the side wall 5, a steel guide body 6 is provided.
Are arranged in a slanting cylindrical shape over the entire length of the inclined shaft 3. As shown in FIG. 1, the guide bodies 6 are arranged in a line in the ground 2 in a shape that can surround the circumference of the inclined shaft 3 from the ground 2a through the wellhead 3a, that is, a shape corresponding to the outer peripheral shape of the caisson 50. Are formed by a plurality of steel pipes 61 each having a columnar shape.

Further, at the bottom of the inclined shaft 3, as shown in FIG. 2, a bottom concrete 10 having water impermeability is cast in a form in which a top end 10a is formed horizontally as shown by hatching in FIG. It is installed, and on the bottom concrete 10,
The starting base 30 is formed so that the shield excavator 45 that excavates and forms the shield tunnel 46 can be started from the space supported by the side wall 5. Therefore, the starting base 30 is formed of a structure in which the side wall 5 including the caisson 50 is a side wall and the bottom concrete 10 is a floor slab. At the starting base 30, as shown in FIGS. 3 to 4, the shield excavator 45 cuts through the tunnel forming position 5p set in the caisson 50 forming the side wall 5 and shields the tunnel 46 in the ground 2. Therefore, the shield excavator 45 is aligned with the cross-sectional position of the shield tunnel 46 to be constructed at the starting base 30, as shown in FIG.

Shield starting area 1 and existing track 41
Etc. have the above-mentioned configuration, the existing track 4
When constructing the shield tunnel 46 in the ground 2 located vertically below 1, the construction of the inclined shaft 3 is first performed. First, as shown in FIGS. 1 to 3, on the ground 2a, from the existing track 41 to the existing track 41
In a direction orthogonal to the track center CT1 of the existing track 41, that is, a point separated by a distance that does not affect the service of the existing track 41, that is, the existing track 4
A place to be the wellhead 3a is set by surveying at a place adjacent to 1 with a predetermined distance in the horizontal direction.

Next, as shown in FIG. 1, a plurality of steel pipes 61 are formed in a shape corresponding to the outer peripheral shape of the side wall 5 by the caisson 50 to be subsequently laid from the outer circumference of the portion to be the wellhead 3a, that is, Each of the steel pipes 61 is cast diagonally into the ground 2 from the ground 2a corresponding to the wellhead 3a toward the planned place where the shield tunnel 46 is to be formed, with the predetermined gradient α shown in FIG. The steel pipe 61 is the inclined shaft 3
It will be added and placed as appropriate to reach the point corresponding to the depth of. In this way, when a plurality of steel pipes 61 are driven into the ground 2, the slant-cylindrical guide body 6 is installed as a guide means for the caisson 50 to be further sunk. On this occasion,
Since each steel pipe 61 has an extremely small diameter as compared with the inclined shaft 3, it is easy to drive the guide body 6 into the ground, and there is no concern that the ground 2 will be disturbed by this.

Therefore, by using the guide body 6, the caisson 50 having a shape corresponding to the shape of the side wall 5 and having the inclined shaft space 50s formed therein is inclined so as to form a predetermined gradient α, and the caisson 50 is formed. It is installed in the wellhead 3a so that the member axis is in conformity with the inclined shaft axis CT3. Then, the ground 2 at the location where the caisson 50 is to be installed is excavated and removed, and the guide body 6 is used as a guide to press fit into the ground 2 until the location where the shield tunnel 46 is to be formed is reached. Then, the caisson 50 already has a predetermined gradient α.
The guide body 6 placed in the ground 2 in the form of a guide is used as a guide, and is smoothly press-fitted and sunk into the ground 2, whereby the formation of the inclined shaft 3 and the construction of the side wall 5 are simultaneously advanced. Go. At this time, the caisson 50 is guided in its sunk position by the guide body 6 already placed in the ground 2, and is sunk with a predetermined gradient α in a form that accurately corresponds to the formation shape of the inclined shaft 3. In addition, since the guide body 6 is arranged on the outer periphery of the caisson 50 during the digging, the excavation site associated with the laying of the caisson 50 is on the inner side of the guide body 6, and excavation work is also suitably performed. As a result, even a large oblique space having a slope α such as the inclined shaft 3 is stably formed.

In this way, the caisson 50 is sunk to a predetermined depth to reach the place where the shield tunnel 46 is to be formed,
After completing the construction of the side wall 5 and the formation of the inclined shaft 3,
The bottom concrete 10 is poured as shown by the hatching in FIGS. Since the inclined shaft 3 is an oblique space, the side wall 5 has a lower side shown on the right side in FIG. 2 whose length is gradually longer than the high side shown on the left side in FIG. 2 has an irregular shape in which the upper surface side and the lower surface side are not parallel in the embodiment shown in FIG. 2 because its top end 10a is formed substantially horizontal, but the bottom of the inclined shaft 3 is parallel to the ground 2a. You may use such a caisson.

When the bottom concrete 10 is cast in this way, the space above the bottom concrete 10 is arranged in a form of overlapping on the line of the shield tunnel 46 to be newly constructed as shown in FIG. The stable space is supported by the body 6 and the side wall 5, and is protected by the bottom concrete 10. Therefore, the space above the bottom concrete 10 can be used as the starting base 30. Therefore, only by forming the inclined shaft 3 using the caisson 50 and placing the bottom concrete 10 at the bottom of the shaft, the starting base 3 having the side wall 5 and the bottom concrete 10 as a structure is formed.
0 can be constructed, and the steps involved in constructing the starting base 30 are extremely simple. Further, since the starting base 30 needs to be arranged in the ground 2 below the existing track 41 in the vertical direction, at the time of its construction, the ground 2 is subjected to chemical injection or the like to surround the inclined shaft 3 and its lower side. Although the ground 2 may be improved and stabilized, the area targeted for such ground improvement is limited to the area around the inclined shaft 3 and the area below it, so a small ground improvement is sufficient.

When the starting base 30 is thus formed,
The shield excavator 45 is lowered from the wellhead 3a through the inclined shaft 3 onto the bottom concrete 10, and the shield excavator 45 is arranged in the excavation direction of the shield tunnel 46 as shown in FIGS. 3 to 4. Let Then, it is not necessary to change the direction of the shield excavator 45 in the inclined shaft 3,
The excavation of the shield tunnel 46 can be started immediately. Therefore, the shield excavator 45 is started by cutting the tunnel forming portion 5p of the caisson 50 and the guide body 6 corresponding thereto and propelling it into the ground 2. Then, it is possible to safely and accurately excavate the shield tunnel 46 below the existing track 41 along the extension direction of the existing track 41. Therefore,
The setup until the start of excavation of the shield tunnel 46 is simple, and since the tunnel entrance 3a and the tunnel formation position 5p of the caisson are connected in a straight line via the inclined shaft 3, the inclined shaft 3 was used as a working shaft. Excellent workability when used. In addition, the inclined shaft 3 formed by the procedure described above,
Since the shape is firmly supported by the guide body 6, the caisson 50, and the bottom concrete 10, after the completion of the construction of the shield tunnel 46, the inclined shaft 3 is used as a ventilation tower, a part of the station building, a vertical shaft for inspection, a slam passage, etc. It can be usefully and safely used for the purpose.

In the above-described embodiment, the guide body 6 which is the guide means is arranged in a cylindrical shape corresponding to the outer peripheral shape of the caisson 50. However, the guide body 6 is It does not necessarily have to be cylindrical. That is, in the example shown in FIG. 5, the guide body 7 is formed and installed in a form excluding the tunnel formation position 5p of the caisson 50 described above. Then, the guide body 7 is the caisson 50.
Does not hinder the starting operation of the shield excavator 45 that cuts through the tunnel formation position 5p and starts while the guide excavator is installed in the ground 2 with a predetermined gradient α. Therefore, the shield excavator 45 can be smoothly started. The guide body 7 not shown in FIG. 5 may be installed only near the tunnel forming position 5p of the caisson 50, or may extend over the entire length of the inclined shaft 3.

Further, in the above-mentioned embodiment, the example in which the inclined shaft 3 is formed in the inclined columnar shape by using the caisson 50 formed in the inclined cylinder shape is described, but the formation shape of the inclined shaft is not limited to this. For example, as shown in FIGS. 6 to 7, the inclined shaft 4 having a rectangular cross section may be formed. To form the rectangular inclined shaft 4, the existing track 41
A wellhead 4a is set in a rectangular shape at a predetermined location on the ground 2a adjacent to the horizontal direction, and a plurality of steel pipes 61 are slanted in a direction from the wellhead 4a to a place where the shield tunnel 46 is to be formed.
Are installed in the form of a rectangular tube to form the guide body 8,
The guide body 8 is used as a guide means and the inside of the inclined shaft space 51s
The rectangular caisson 51 on which is formed is sunk until the shield tunnel 46 is to be formed.
The start base 30 is on the bottom concrete 10 that is placed at the bottom of 1. Therefore, the construction procedure is no different from the case of the oblique column 3 of the oblique column described above, and the cross sectional shape of the oblique shaft can be freely selected. That is, the shape of the inclined shafts such as the inclined shafts 3 and 4 is not limited to the one whose cross section has a circular shape or a rectangular shape as described in the present embodiment. Any shape, such as a horseshoe shape or a spectacle shape, may be used.

Further, the guide means such as the above-mentioned guide bodies 6 and 7 may be installed one by one by arranging a plurality of steel pipes 61 in a row like in the embodiment, that is, A plurality of steel pipes 61 connected via a joint may be driven and installed as guide means. Further, the guide means assembled in a tubular shape from the beginning may be driven obliquely from the wellholes such as the wellholes 3a and 4a. Further, the guide means does not have to be made of a steel material such as the steel pipe 61, and may be a resin material, a PC member, a stone material, or the like.

Further, in the above-mentioned embodiment, the inclined shafts 3, 4
Although an example of using open type caissons 50 and 51 to form the inclined shaft and the like to place the starting base 30 on the bottom concrete 10 has been described, for the construction of the starting base 30, the caisson is used. Caisson other than 50 and 51 or other ground supporting means may be used. 8 to 10 show examples of the starting base 30 by the inclined shaft 3 using another caisson or other ground supporting means. The inclined shaft 3 shown in FIGS. 8 to 10 is formed so as to form a predetermined gradient α from the front side to the back side of the paper surface.

As another example of the caisson, as shown in FIG. 8, there is a pneumatic type caisson 52 in which an inclined shaft space 52s is formed, and the caisson 52 is surrounded by a blade 52a at the bottom thereof. A working chamber 52c is provided which is isolated from the inclined shaft space 52s side by the partition wall 52b. In FIG. 8, the bottom concrete 10 is already placed as the bottom portion of the caisson 52 in the working chamber 52c. Therefore, the caisson 52 and the bottom concrete 10 are shielded from the bottom of the inclined shaft 3 formed by the inclined shaft space 52s. The starting base 30 is configured so that 45 can be started.

In the construction procedure of the example of FIG. 8, first, the same guide body 6 as that described above is installed, and the caisson 52 is used as a guide means for the guide body 6 from the wellhead 3a to the place where the shield tunnel 46 will be formed. Until it reaches, and after that,
The bottom concrete 10 is poured into the working chamber 52c. Then, the bottom of the inclined shaft space 52s is properly supported by the pneumatic type caisson 52 in such a form that it can withstand high water pressure even during caisson digging work, and then is blocked by the bottom concrete 10. Therefore, even when the starting base 30 is constructed at a large depth, safe and accurate work can be performed.

Further, FIG. 9 shows a cylindrical ground support means 9
An example of excavating and forming the inclined shaft 3 by using 0 is shown. The ground support means 90 is, for example, an earth retaining material 9 having water impermeability.
Is installed in a diagonal direction in the ground 2 in a form of being arranged in a cylinder around the inclined shaft 3. The starting base 30 can be constructed accurately even by using the ground supporting means 90. That is, in the construction procedure of the example shown in FIG. 9, similarly to the construction procedure of the starting base 30 using the caisson described above, first, the wellhead 3a is set at a location adjacent to the existing track 41 in the horizontal direction on the ground 2a. The ground support means 90 composed of the earth retaining material 9 is installed in an oblique direction from the wellhead 3a toward the planned formation location of the shield tunnel 46. Along with this, the improved ground 2k is formed near the bottom of the ground supporting means 90, the ground 2 inside the ground supporting means 90 is excavated, and the inclined shaft 3 is formed to form the wellhead 3a and the shield tunnel 46. Form in a form that connects the points. When the bottom concrete 10 is placed on the bottom of the inclined shaft 3, the starting base 30 is located on the bottom concrete 10.
Therefore, even if the caisson is not installed, the inclined shaft 3 is formed, and the ground support means 90 supporting the inclined shaft 3 and the bottom concrete 10 cast on the bottom of the inclined shaft 3
It is possible to construct the starting base 30, which allows a simpler construction process, that is, a shorter starting period.
It is possible to build 0. In addition, the required materials, equipment and facilities are simple.

Further, FIG. 10 shows an example in which the side wall concrete 11 is cast on site on the inner peripheral side of the ground supporting means 90. In the construction procedure of FIG. 10, similarly to the example of FIG. 9, the ground support means 90 is installed in a diagonal direction from the wellhead 3a toward the planned formation location of the shield tunnel 46, and at the bottom of the ground support means 90. After the improved ground 2k is formed in the ground, the ground 2 inside the ground supporting means 90 is excavated, and the inclined shaft 3 is formed in such a manner that the well hole 3a and the planned site of the shield tunnel 46 are connected to each other. Then, the bottom concrete 10 is poured, and further the side wall concrete 11 is cast on site. Then, the construction of the starting base 30 is completed in such a manner that the bottom concrete 10, the ground supporting means 90, and the side wall concrete 11 cast on the bottom of the inclined shaft 3a stably support the inclined shaft 3 formed by them. Therefore, even after the shield excavator 45 is started from the starting base 30 and the shield tunnel 46 is constructed, the inclined shaft 3
Can be used effectively and safely as a ventilation tower, a part of station building, an inclined shaft for inspection, a blame passage, etc.

In each of the above-described embodiments, the existing ground upstream passage facility is the existing track 41. However, in the present invention, the existing ground upstream passage facility is a flow passage for people and objects on the ground. Other items may be used if they are present. For example, as shown in FIG. 11, the existing ground upstream passage facility may be an existing road 56 on which an automobile or the like is distributed (in this case, the number CT1 in the drawing indicates the center of the road). Further, for example, as shown in FIG. 12, the existing ground upstream passage facility may be an existing river 57 in which rainwater or the like flows (in this case, the number CT1 in the drawing indicates the river center). Further, in addition to these examples, the existing ground upstream passage facility may be an existing sidewalk or the like.

[0026]

As described above, according to the first aspect of the present invention, the existing track 41 and the existing road 5
6. In forming the shield tunnel 46 extending along the existing ground upstream passage facility in the ground 2 vertically below the existing ground upstream passage facility such as the existing river 57, the existing ground distribution is used. Wells such as wells 3a and 4a are set horizontally adjacent to the road facility, and the cylindrical ground support means 90 is directed obliquely from the well to the planned formation location of the shield tunnel 46. While installing, excavating the ground 2 inside the ground supporting means 90,
The inclined shafts such as the inclined shafts 3 and 4 are formed in such a manner as to connect the pit mouth and the planned formation location of the shield tunnel 46, and the bottom concrete 10 is placed at the bottom of the inclined shaft to start the starting base 3
Since the shield starting base such as 0 is constructed and configured, it is possible to easily arrange the shield starting base at the place where the shield tunnel 46 is to be formed by a simple construction process. That is, the shield excavator 45 is required to start from a planned formation location of the shield tunnel 46 located vertically below the existing ground upstream passage facility, which is necessary when constructing a shield starting base for this purpose. The excavation process to be performed is only the excavation process of the inclined shaft, and it is not necessary to change the excavation direction midway. Further, since the bottom concrete 10 can be used as a floor slab for installing the shield excavator 45, measures against water shield below the shield starting base and the construction of the floor portion as a structure are constructed at once. Moreover, when excavating, it is not necessary to temporarily receive the existing ground upstream passage facility. In addition, when constructing the shield starting base, the area where ground stabilization is to be done is only around the inclined shaft. Furthermore, the ground support means 90 can prevent the loosening of the ground due to excavation of the inclined shaft as much as possible. The ground improvement required to build the building is small. Further, since the planned formation location of the shield tunnel 46 and the wellhead are directly connected by the inclined shaft, the work of installing the shield excavator 45 on the bottom concrete 10 at the time of starting the shield is easy. The materials, equipment, etc. required for the construction work of the shield tunnel 46 are smoothly transported by using the inclined shaft as a working shaft. That is, the vertical shaft and the horizontal shaft connected to the vertical shaft (conventional shaft) change the transportation direction of materials and equipment in the middle of the process, so a plurality of types of transportation means are required. If the inclined shaft is used, the transport direction becomes straight, so that it is not necessary to use several types of transport means in combination.

The invention according to claim 2 of the present invention is characterized in that, in the invention according to claim 1, the existing ground upstream passage facility is an existing track such as the existing track 41. Therefore, the following effect is produced in addition to the effect according to the first aspect of the invention. That is, the present invention is superior to the temporary receiving method, which is one of the conventional methods, that is, the method in which an existing track is temporarily received by a track protector or the like, in the following points. That is, in this conventional temporary receiving method, especially when the existing track is a railroad line that is in service, the temporary receiving process becomes very complicated and inconvenience occurs, but in the present invention, this temporary receiving work is performed. This is convenient because the work process is simplified by eliminating the need for. In addition, since the existing track, which is a railway line in service, can be used in a state that is almost the same as the state before construction, it may be necessary to operate the train slowly due to the existing track being temporarily received. It is convenient without anything.

The invention according to claim 3 of the present invention is characterized in that, in the invention according to claim 1, the existing ground upstream passage facility is an existing road such as an existing road 56. Therefore, the following effect is produced in addition to the effect according to the first aspect of the invention. That is, the present invention is superior to the temporary receiving method, which is one of the conventional methods, that is, the method of constructing an existing road by temporarily receiving it, in the following points. That is, in the conventional temporary receiving method, when the work of temporarily receiving the existing road is performed, for example, the road surface of the existing road is made of an iron plate material and the iron plate material is temporarily received. When an automobile or the like passes over the iron plate material, a vibration or the like occurs, which causes discomfort. However, in the present invention, since this temporary receiving work is unnecessary, the existing road in service can be used in a state almost the same as the state before construction (that is, since no iron plate material etc. is used), it is possible to use the conventional shaking motion. This is convenient because there is no inconvenience such as occurrence of discomfort and the resulting discomfort. Further, since the existing road in service can be used in a state substantially the same as the state before the construction, it is convenient that there is no need to drive the vehicle slowly.

The invention according to claim 4 of the present invention is characterized in that, in the invention according to claim 1, the existing ground upstream passage facility is an existing river such as the existing river 57. Therefore, the following effect is produced in addition to the effect according to the first aspect of the invention. That is, the present invention is superior to the temporary receiving method, which is one of the conventional methods, that is, the method of constructing an existing river by temporarily receiving it, in the following points. That is, in the conventional temporary receiving method, there were many difficulties such as measures against water leakage when the work of temporarily receiving the existing river was performed. However, in the present invention, this temporary receiving work is unnecessary, and the existing river in service can be used in a state substantially the same as the state before construction. In addition, since the existing river in service can be used in a state that is substantially the same as the state before construction, it is convenient because the flow rate of the river does not change carelessly.

The invention according to claim 5 of the present invention is the same as the invention according to claim 1, wherein the ground support means 9 is provided.
Since No. 0 is constituted by the earth retaining material 9 arranged around the inclined shaft, the ground support means composed of the soil retaining material can earth retain the ground around the inclined shaft. Therefore, the inclined shaft becomes a space more stably supported by the ground support means 90 composed of the earth retaining material 9, and the ground under the existing ground upstream passage facility is prevented from collapsing to the inclined shaft side. Construction of all new shield tunnels,
Safety will be increased in both service of the existing ground up passage facilities. Further, the looseness of the ground around the inclined shaft is more surely suppressed by the ground supporting means, and as a result, the ground improvement required for obtaining the desired ground stability is reduced.

The invention according to claim 6 of the present invention includes the existing track 41, the existing road 56, the existing river 57, etc. in the ground 2 located vertically below the existing ground upstream passage facility. When forming the shield tunnel 46 extending along the ground upstream passage facility, the wells 3a, 4a and the like are set at locations horizontally adjacent to the existing ground upstream passage facility, and guide bodies 6, 7, 8 or the like guide means from the wellheads 3a, 4a or the like to the shield tunnel 4
The caisson 50, 51, 52, etc., which is installed in a diagonal direction in the shape of the planned formation location of 6, and in which oblique shaft spaces such as the inclined shaft spaces 50s, 51s, 52s are formed, is guided from the hole opening to the guide. Using the means as a guide, it is sunk until the shield tunnel 46 is to be formed,
Since the bottom concrete 10 was placed on the bottom of the caisson to construct and construct the shield starting base such as the starting base 30, the caisson was installed to connect the inclined shaft space, the wellhead and the planned location of the shield tunnel 46. It can be arranged in a straight line in the shape of a circle. Therefore, the caisson's inclined shaft space thus arranged functions as the inclined shaft described in the above-mentioned invention of claim 1, so that by using the caisson, a shield starting base is formed at the planned formation location of the shield tunnel 46. It can be easily arranged by a simple construction process. That is, it is not necessary to change the excavation direction or temporarily receive the existing ground upstream passage facility when constructing the shield starting base under the existing ground upstream passage facility.
In addition, since the caisson, as is well known, is constructed so that its laying work is performed inside the inclined shaft space, no large-scale ground improvement is required, and furthermore, the inclined shaft space placed in the ground is safely supported by the caisson. Since it takes shape, the construction of the shield starting base and the ground improvement required for its use are small. In addition, caisson has its sunk process (ie construction of the side wall of the inclined shaft) and ground excavation (ie formation of the internal space of the inclined shaft).
Work is done simultaneously, so construction efficiency is good. Furthermore, since the guide means can guide the caisson accurately in an oblique direction from the wellhead toward the planned formation location of the shield tunnel 46 when the caisson is sunk, it is easy to maintain the caisson's sunk position. Therefore, the oblique installation direction of the caisson does not hinder the caisson sunk work.

The invention according to claim 7 of the present invention is characterized in that, in the invention according to claim 6, the existing ground upstream passage facility is an existing track such as the existing track 41. Therefore, the following effect is brought about in addition to the effect according to the invention of claim 6. That is, the present invention is convenient because the complicated temporary receiving work is unnecessary as compared with the conventional temporary receiving method, which is one of the conventional methods, and the work process is simplified. Moreover, since the existing track, which is the railway line in service, can be used in a state that is substantially the same as the state before the construction, it is convenient without requiring slow driving of the train.

The invention according to claim 8 of the present invention is characterized in that, in the invention according to claim 6, the existing ground upstream passage facility is an existing road such as an existing road 56. Therefore, the following effect is brought about in addition to the effect according to the invention of claim 6. That is, according to the present invention, since the temporary receiving work is unnecessary as compared with the temporary receiving method which is one of the conventional construction methods, the existing road in service is not formed by the temporary road surface using the iron plate material or the like. Since it can be used in almost the same state as before the construction, it is convenient because there is no inconvenience such as vibration causing uncomfortable feeling. Further, since the existing road in service can be used in a state substantially the same as the state before the construction, it is convenient that there is no need to drive the vehicle slowly.

The invention according to claim 9 of the present invention is characterized in that, in the invention according to claim 6, the existing ground upstream passage facility is an existing river such as the existing river 57. Therefore, the following effect is brought about in addition to the effect according to the invention of claim 6. That is, the present invention does not require the work of temporarily receiving the existing river as compared with the conventional receiving method which is one of the conventional construction methods, and the existing river in use is used in a state substantially the same as the state before construction. Since it is possible, it is convenient because no water leakage measures are required. In addition, since the existing river in service can be used in a state that is substantially the same as the state before construction, it is convenient because the flow rate of the river does not change carelessly.

According to a tenth aspect of the present invention, in the invention according to the sixth aspect, the guide means is
Since it is configured by a plurality of columnar members such as the steel pipes 61 arranged along the outer peripheral shape of the caisson,
The guide means can be installed by arranging and driving a plurality of columnar members in a line in the ground. Then, since it is a relatively easy work to drive the columnar members into the ground, if the guide means is formed by arranging a plurality of the columnar members,
In order to form a shape that can guide the caisson, it is possible to work in a diagonal direction with the shape facing from the wellhead to the place where the shield tunnel 46 is to be formed, with good workability.

In the invention according to claim 11 of the present invention, in the invention according to claim 6, the guide bodies 6 and 8 are provided.
Since the guide means such as the above is arranged in a cylindrical shape corresponding to the outer peripheral shape of the caisson, the caisson can be submerged in the ground surrounded by the guide means. Therefore, the caisson is more surely installed in a slanting direction toward the planned shield tunnel formation position without deviating from the tubular guide means. In addition, since the portion to be excavated for caisson deposition is inside the tubular guide means that is placed before the caisson deposition, excavation and the caisson deposition associated therewith can be performed more safely. .

According to a twelfth aspect of the present invention, in the invention according to the sixth aspect, the guide means such as the guide body 6 is installed in a form excluding the tunnel forming position 5p of the caisson. The guide means is not arranged at the tunnel forming position 5p. Therefore, when the shield excavator 45 starts,
The tunnel excavation position 5p of the caisson is excavated into the ground in a form of being cut through, but at this time, the shield excavator 45 can smoothly start because there is no guide means at the tunnel formation position 5p.

[Brief description of drawings]

FIG. 1 is a plan view of a ground portion of a shield starting base under construction according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II and II in FIG.

FIG. 3 is a sectional view taken along the line III and III in FIG.

FIG. 4 is a sectional view taken along arrows IV and IV.

5 is a cross-sectional view showing another example of the shield starting base shown in FIG.

FIG. 6 is a plan view of a ground portion of a shield starting base being constructed according to another embodiment of the present invention.

FIG. 7 is a plan sectional view of an underground portion of the shield starting base shown in FIG.

FIG. 8 is a diagram showing a construction procedure of still another embodiment of the present invention.

FIG. 9 is a diagram showing a construction procedure of still another embodiment of the present invention.

FIG. 10 is a diagram showing a construction procedure of still another embodiment of the present invention.

FIG. 11 is a view showing a construction procedure of still another embodiment of the present invention.

FIG. 12 is a diagram showing a construction procedure of still another embodiment of the present invention.

FIG. 13 is a sectional side view showing an example of a conventional shield starting base under an existing track,

14 is a sectional view taken along the line XI and XI of FIG.

FIG. 15 is a sectional side view showing another example of a conventional shield starting base under an existing track.

16 is a sectional view taken along line XIV and XIV of FIG.

[Explanation of symbols]

 2 ... Ground 3, 4 ... Diagonal shaft 3a, 4a ... Wellhead 30 ... Shield starting base (starting base) 41 ... Existing ground upstream passage facility (existing track) 56 ... Existing ground upstream passage facility (existing) Road) 57 …… Existing ground upstream passage facility (existing river) 46 …… Shield tunnel 9 …… Earth retaining material 90 …… Ground support means 6, 7, 8 …… Guide means (guide body) 61 …… Column member (Steel pipe) 10 ... bottom concrete 50, 51, 52 ... caisson 50s, 51s, 52s ... inclined shaft space 5p ... tunnel formation position

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Akira Abe 3-10-1, Iwamoto-cho, Chiyoda-ku, Tokyo Mitsui Construction Co., Ltd. (72) Hirofumi Fukushima 3--10-1, Iwamoto-cho, Chiyoda-ku, Tokyo No. Mitsui Construction Co., Ltd. (72) Inventor Kazuyoshi Chiyo 3-10-1 Iwamotocho, Chiyoda-ku, Tokyo Mitsui Construction Co., Ltd. (72) Nobuyuki Yamamoto 3-10-1 Iwamoto-cho, Chiyoda-ku, Tokyo No. Mitsui Construction Co., Ltd. (72) Inventor Akira Honma 3-10-1, Iwamotocho, Chiyoda-ku, Tokyo Mitsui Construction Co., Ltd.

Claims (12)

[Claims] 1. When forming a shield tunnel extending along the existing ground upstream aisle facility in the ground vertically below the existing ground upstream aisle facility, it is horizontal to the existing ground upstream aisle facility. A wellhead is set at a place adjacent to the direction, and a cylindrical ground support means is installed in an oblique direction from the wellhead toward the planned formation location of the shield tunnel, and the ground inside the ground support means is installed. Excavating, the inclined shaft is formed so as to connect the well mouth and the planned place for forming the shield tunnel, the bottom concrete is cast at the bottom of the inclined shaft, the shield starting base is constructed, and the shield is constructed. How to build a starting base. 2. The method for constructing a shield starting base according to claim 1, wherein the existing ground upstream passage facility is an existing track. 3. The method for constructing a shield starting base according to claim 1, wherein the existing ground upstream passage facility is an existing road. 4. The method for constructing a shield starting base according to claim 1, wherein the existing ground upstream passage facility is an existing river. 5. The method for constructing a shield starting base according to claim 1, wherein the ground support means is made of a soil retaining material arranged around the inclined shaft. 6. When forming a shield tunnel extending along the existing ground upstream aisle facility in the ground vertically below the existing ground upstream aisle facility, it is horizontal to the existing ground upstream aisle facility. A well is set up in a place adjacent to the direction, and the guide means is installed diagonally in a form from the well to the planned location of the shield tunnel. From the guide means as a guide until it reaches the planned location of the shield tunnel, by placing a bottom concrete at the bottom of the caisson, constructing a shield start base, configured, shield start base of How to build. 7. The method for constructing a shield starting base according to claim 6, wherein the existing ground upstream passage facility is an existing track. 8. The method for constructing a shield starting base according to claim 6, wherein the existing ground upstream passage facility is an existing road. 9. The method for constructing a shield starting base according to claim 6, wherein the existing ground upstream passage facility is an existing river. 10. The method for constructing a shield starting base according to claim 6, wherein the guide means is composed of a plurality of columnar members arranged along the outer peripheral shape of the caisson. 11. The guide means is installed in a cylindrical shape corresponding to the outer peripheral shape of the caisson.
The method for constructing a shield starting base according to claim 6. 12. The method for constructing a shield starting base according to claim 6, wherein the guide means is installed in a form excluding a tunnel forming position of the caisson.