JP2934293B2 - Branchable multiple shield excavator and its branch excavation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application field] The present invention relates to a multiple shield tunnel having an overlapping circular cross-sectional shape and one or a plurality of single circular shield tunnels branched from the tunnel. Regarding a branchable multiple shield excavator suitable for building continuously at the starting point and its branch excavation method, as a typical application field,
Continuous construction of subway station tunnels and inter-station tunnels.

[Conventional technology]

There is no example of a technique for continuously constructing tunnels of different forms, such as a tunnel at a subway station and a tunnel between stations, using a shield method. The following method is conceivable.

This method is, for example, rotary drilling cutter head 103, 104,
Three single circular shield bodies 100, 10 each with 105
1,102 are arranged side by side in the horizontal direction, and shield bodies 100 and 101
Are connected by connecting portions 106 and 107, and the shield main bodies 100 and 102 are connected by connecting portions 108 and 109 and excavated at the same time, thereby forming a central station building space and a left and right rail space as a station tunnel. One round shield tunnel 110,111,
29 is constructed as shown in FIG.
And 107, 108 and 109 are separated, and then the left and right two single circular shield bodies 101 and 102 are individually excavated,
On the extension of the station tunnel, an inter-station tunnel consisting of two single circular shield tunnels is built continuously.

[Problems to be solved by the invention]

The above method is one of the methods for solving the problem of land use of a shaft in tunnel construction in an urban area, but has the following problems in construction.

(1) When the shield body 100, 101, 102
As shown in FIG. 8, the connection portions 106 to 109 remain as protrusions on each shield body, so that even when digging alone, it is necessary to excavate the ground by an amount corresponding to these connection portions. More.

(2) Three shield tunnels 110, 111, 112 arranged side by side
Because of the separation, additional work is required to cut and expand the unstable ground between the tunnels as indicated by the dotted lines 113 and 114 in order to construct the station, which leads to an increase in construction costs and a longer construction period.

On the other hand, by using a multiple shield excavator that excavates three tunnels partially in parallel with each other, a central station building space 83 and left and right rail space 84, 85 as shown in FIG. 21 are formed. There is a plan to build a station tunnel 82 with an overlapping circular cross section, but in the conventional technology, the station tunnel and the tunnel between stations are separately constructed using dedicated shield excavators corresponding to each tunnel type. Therefore, there was a problem in securing land for starting shafts and economic efficiency.

The present invention has been made in view of the above points, and has been described in which a multiple shield tunnel having an overlapping circular cross-sectional shape and one or a plurality of single circular shield tunnels branched therefrom are continuously connected starting from one shaft. A multi-branch shield tunneling machine capable of being built and capable of continuously, economically, quickly and safely constructing tunnels of different forms such as a subway station tunnel and a station-to-station tunnel, and its branch excavation. The aim is to provide a method.

[Means for solving the problem]

In order to achieve the above object, a branchable multiple shield excavator according to the present invention includes a plurality of cylinders connected in parallel with each other and with adjacent cylinders partially overlapping each other. A multiple shield body having a circular cross-sectional shape, and a single cylindrical shield housed in the multiple shield body so as to be on the same line as some of the plurality of cylindrical portions. A main body and a cutter head for excavating a front face of both shield main bodies, wherein the cutter head is supported by the first cutter head supported by the multiple shield main body and the single circular shield main body. Second
Wherein the single circular shield main body includes a driving device for operating the second cutter head, a discharging device for discharging excavated earth and sand backward, a jacking device for excavation including a propulsion jack and an erector, It is configured so as to be retracted and branch off from the multiple shield body so as to be able to excavate independently. The propulsion jack is used commonly for multiple shield excavation and single excavation of a single circular shield body.

The first cutter head preferably has a shape in which an outer peripheral portion is partially cut out so as not to interfere with the single circular shield main body at the start of branch propulsion.

In order to ensure the stability of the face, the first and second
Are arranged in substantially the same plane in front of the shield bodies, and only the second cutter head is a rotary excavation type cutter head, and the first cutter head has a partially cutout outer peripheral portion. It is preferable that the cutter head has an oscillating excavation type that has a bent shape and swings within a range that does not interfere with the second cutter head.

In addition, from the viewpoint of simplifying the rear equipment by consolidating the earth removal equipment, the first cutter head is disposed forward of the second cutter head, and the first cutter head and the multiple shield main body are arranged. And a sand guide for guiding the excavated earth and sand by the first cutter head to an earth removal device in the single circular shield body disposed adjacently.

As a branch excavation method of the multiple shield excavator of the present invention, a tail skin plate is completed in advance in the single circular shield main body, and after completing the duplication of the overlapping circular cross section of the scheduled section, the inside of the single circular shield main body is removed. The erector is moved forward from the position at the time of assembling the overlapping circular segment, and a single circular segment connected to the existing overlapping circular segment is assembled in the newly created segment assembling space, and the single circular segment is used as a reaction force receiver. A method in which a single circular shield body is propelled into the ground to start branch excavation, and after completing excavation of an overlapping circular cross section of a predetermined section, the single circular shield body is moved a predetermined distance from the multiple shield body. Move forward, add an additional tail skin plate to the rear of the single circular shield body at the advanced position, and add the newly created segment Assembling a single circular segment preparative assembly space, the single circular segment to propel said single circular shield body as a reaction force received in the ground, and a method of initiating branch excavation.

[Action]

In the multiple shield excavator of the present invention, in a state where a single circular shield body is stored in the multiple shield body, the first and second cutter heads respectively supported by both shield bodies are simultaneously operated to cut the face. While excavating, utilizing the equipment such as the earth removal device, propulsion jack, and erector stored in both shield bodies, the overlapping circular segments assembled in the tail part of the multiple shield body are used as reaction force receivers to receive the reaction force. , The excavation of the overlapping circular section is performed, the excavation is stopped at the planned branch point, the single circular shield body is separated from the multiple shield body, only the second cutter head is operated, and the single A single circular shield book with a single circular segment assembled by connecting to the existing overlapping circular segment in the tail part of the circular shield body as a reaction force receiver The by propelling alone, it can be transferred to a branch excavation of construction the shield tunnel single circular cross-section on the extension of the excavation line so far.

All work such as separation of the single circular shield body at the time of transition, segment assembly, addition of tail skin plate, etc. can be done inside the multiple shield body, so it is safe without exposing the ground, No connecting projection remains on the single circular shield body. In addition, the shield tunnel having the overlapping circular cross section obtained by the multiple shield excavator of the present invention can be used for constructing an underground station or the like without requiring additional work for cutting and expanding between adjacent tunnels.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 24.

FIG. 1 is a plan view showing a state immediately after a branch excavation of a multiple shield excavator according to the present invention, that is, a state immediately after a transition from an overlapping circular excavation to a single circular excavation.
3 is a single circular shield body, 4, 5, 6 are cutter heads, 8, 9
Is a single circular segment constructed during single circular excavation. The two-dot chain lines 2 'and 3' indicate a single circular shield body 2,
Numeral 3 indicates the position when stored in the multiple shield main body 1, and two-dot chain lines 5 'and 6' indicate the positions of the cutter heads 5 and 6 at this time.

FIG. 2 is a front view of an overlapping circular segment constructed during overlapping circular digging. Duplicate circular segment 7 shown in this drawing, the diameter is left circular portion 7b of the central circular portion 7a, in diameter larger triplicate shaped 7c, a plurality of segment pieces S ₁ to S _n and center post P ₁ of the second column , assembled by P _2, the branch point, the single circular segment 8 and 9 is adapted to be connected to the right and left circular section 7b, 7c.

3 to 5 are detailed structural views of a first embodiment of the multiple shield excavator according to the present invention. As shown in these figures, the multiple shield body 1 is configured by connecting three cylindrical portions 1a, 1b, 1c in parallel with each other and in a lateral direction such that adjacent cylindrical portions partially overlap. And has an overlapping circular cross-sectional shape surrounding the overlapping circular segment 7 shown in FIG. Except for the tail portion, the inside of the multiple shield main body 1 includes a part of the peripheral wall of the left and right cylindrical portions 1b and 1c in the left and right storage rooms for storing the single circular shield main bodies 2 and 3 and the remaining central space 10. The partitions are separated by arc-shaped partitions 11 and 12, and only the tail portion is eliminated, thereby forming a continuous space in which the overlapping circular segment 7 can be assembled (see FIGS. 11 to 14).

Left and right two single circular shield bodies formed in a cylindrical shape
2 and 3 are the left and right cylindrical parts 1b and 1c of the multiple shield body 1, respectively.
And is stored so as to be concentric with the left and right cylindrical portions 1b and 1c. A seal (not shown) is provided between the multiple shield body 1 and the single circular shield bodies 2 and 3 to prevent intrusion of earth and sand and groundwater.
As will be described later, the single circular shield bodies 2 and 3 are fixed by welding or the like inside the multiple shield main body 1 during overlapping circular excavation, and the propulsion reaction force and cutter head acting on the single circular shield bodies 2 and 3 are increased. The rotation reaction force is assigned to the multiple shield main body 1.

The multiple shield body 1 is provided with a partition wall 13 for partitioning the central space 10 back and forth, and a single circular shield body 2,
3 is also provided with partition walls 14 and 15 for partitioning the internal space back and forth. The first cutter head 4 is rotatably supported on the partition wall 13, and the second cutter heads 5, 6 are rotatably supported on the partition walls 14 and 15, respectively. The central axis 16 of the first cutter head 4 extends through the bearing 19 of the partition wall 13 into the rear chamber, and the central axes 17 and 18 of the second cutter heads 5 and 6 respectively.
Extend through the bearing portions 20 and 21 of the partition walls 14 and 15 into the rear chamber.

In the present embodiment, the first and second cutter heads 4, 5, 6
Are arranged in parallel in substantially the same plane in front of the multiple shield main body 1. Here, the axis of the first cutter head 4 is located on the center line of the central cylindrical portion 1a of the multiple shield main body 1, and the axes of the second cutter heads 5 and 6 are the left and right cylindrical portions 1b and 1c, respectively. It is located on the center line. The outer diameter of the first cutter head 4 is substantially equal to the outer diameter of the central cylindrical portion 1a, and the outer diameter of the second cutter heads 5, 6 is equal to the outer diameter of the left and right cylindrical portions 1b,
It is almost equal to the outer diameter of 1c. Therefore, each cutter head 4,
When 5 and 6 are arranged on the same plane, interference between adjacent cutter heads 4 and 5, 4 and 6 must be prevented. Therefore, in the present embodiment, only the second cutter heads 5, 6 are rotary drilling type cutter heads having cruciform spokes 26, 27 and outer peripheral rings 28, 29, and the first cutter head 4 is a long and short spoke. Oscillating excavating cutter having a shape in which the outer peripheral portion is partially cut out, which is formed by 22, 23 and arc-shaped members 29, 25, and which oscillates within a range not to interfere with the second cutter heads 5, 6. By using a head, the above-described problem is solved, and the same plane arrangement of the cutter heads, which is desirable for the stability of the face, is enabled. According to this configuration, it is not necessary to rotate the cutter heads synchronously in order to prevent mutual interference between the cutter heads arranged in the same plane, and the driving mechanism is simplified. Further, it is possible to prevent the first cutter head 4 from interfering with the single circular shield bodies 2 and 3 at the start of the branch excavation and hinder the start. Dangerous work, such as cutting 4, becomes unnecessary.

Excavated earth and sand by the first and second cutter heads 4, 5, and 6 are taken into cutter chambers 30, 31, and 32 formed between the respective cutter heads and the partition walls 13, 14, and 15, and are discharged therefrom. It is discharged behind the partitions 13, 14, 15 by the device. If the shield type is earth pressure type,
As shown in FIG. 7, when a screw conveyor 36 penetrating the partition walls 13, 14, 15 and connected to the cutter chambers 30, 31, 32 is used, and the shield type is a muddy water type, as shown in FIG. So that the pressurized muddy water is supplied to the cutter chamber
The excavated earth and sand are discharged together with muddy water by a mud drain pipe 38, and an independent earth discharging device is provided for each cutter chamber.

As shown in FIG. 6, for example, each cutter head is provided with a cutter driving motor 33 and a rotational force of the cutter driving motor 33.
The driving gears 35 are independently driven by a driving device 35 composed of a driving gear 34 for transmitting the driving gears 6, 17, and 18. However, when the first cutter head 4 is an oscillating excavation type cutter head, only the first cutter head 4 can use a less expensive hydraulic jack driving device instead of the motor drive. .

8 and 9 show a second embodiment of a multiple shield machine according to the present invention. In the present embodiment, the first cutter head 4 is disposed forward, and the second cutter heads 5 and 6 are disposed rearward in a stepwise manner. In this case, either the rotary excavation or the rocking excavation can be selected for the first cutter head 4. However, at the start of branch excavation, the cutter heads 4 and 4 should not be hindered from starting the single circular shield bodies 2 and 3. As in the embodiment shown in FIGS. 3 to 5, the outer peripheral portion is partially cut away, as in the embodiment of FIGS.

In this embodiment, as a means for discharging excavated earth and sand by the first cutter head 4, the central cylindrical portion 1a of the multiple shield main body 1 is extended to near the rear surface of the cutter head 4 as shown in FIG. The bulkhead 13 located at the rear of 4 is provided with a sediment guide 39 having a central portion protruding forward and having a surface inclined left and right from the tip thereof.
The excavated soil by the cutter head 4 is guided to the cutter chambers 31 and 32 of the single circular shield bodies 2 and 3 arranged adjacent to each other by the sediment guide 39, and the sediments 14 and It discharges to the back of 15. This eliminates the necessity of providing an earth removal device behind the partition 13, so that the rear equipment can be simplified and a work space for segment assembly and the like can be widened.

The other configuration is the same as that of the embodiment shown in FIGS. 3 to 5, so that the corresponding portions are denoted by the same reference numerals and the description thereof is omitted.

FIG. 10 shows a third embodiment of the multiple shield excavator according to the present invention, in which first and second cutter heads 4, 5, and
6 differs from the above-described embodiment in that a cutter head 6 having face plates 40, 41, 42 and slits 43, 44, 45 for taking in earth and sand is provided.
In this case, the arrangement of the cutter head and the like can be selected from any one of the first and second embodiments.

Next, an example of an operation procedure when shifting from overlapping circular excavation to single circular excavation in the multiple shield excavator of the present invention will be described with reference to FIGS. 11 and 12. FIG.

In this example, two single circular shield bodies 2 and 3 housed in the multiple shield body 1 are provided with tail skin plates in advance. Are provided with erector supports 46, 47 and 48, 49. The tail skin plate 51 of the multiple shield body 1 extends rearward from the tail skin plates 52, 53 of the single circular shield bodies 2, 3, and has no partition in its tail, so that the overlapping circular segment 7 can be assembled. A continuous space is formed. At the time of overlapping circular excavation, the erector supports 47, 49, and 50 for assembling overlapping circular segments provided in the internal space of the single circular shielding bodies 2 and 3 and the central space 10 of the multiple shielding main body 1 are provided with FIG. The erector as shown in FIG. 19 is attached, and the three circular erectors are used to assemble the overlapping circular segment 7 shown in FIG.

The erector ring 60 shown in FIGS. 18 and 19 is supported by support rollers 61 of erector supports 46 to 50, and is turned by a turning motor 62 through gears 63 and 64.
5 and the arm 66 above the
A pressing beam 67 slidably supported in the incision direction of 5,
A pressing jack 68 that slides the pressing beam 67, and a swing arm 69 that is swingably supported at the tip of the pressing beam 67.
A posture control jack 70 for swinging the swing arm 69,
A one-armed erector provided with a slider 71 supported by a swing arm 69 and a sliding jack 72 for sliding the slider 71 in the front-rear direction, the turning and pressing jack 68 of the erector ring 65, the attitude control jack 70, By the expansion and contraction of the sliding jack 72, the segment piece 73 is gripped by the slider 71 and transported to a predetermined assembling position, and the assembly of one ring of the overlapping circular segment 7 can be performed with the cooperation of three erectors. I have. Also, by extending the pressing beam 67, the assembling time is slightly longer, but the
It is also possible to assemble the overlapping circular segment 7 by using two erectors attached to the overlapping circles 49 and 49.

At the time of overlapping circular excavation, the overlapping circular segments 7 assembled in the multiple shield main body 1 are used as a reaction force, and the propulsion jacks 54 and 55 and the multiple shield main body 1 mounted on the single circular shield main bodies 2 and 3 are used. Both shield bodies are simultaneously propelled by a propulsion jack (not shown) mounted on the central circular portion 1a.

After completing the overlapping circular excavation of the scheduled section, the erectors supported by the erector supports 47 and 49 of the single circular shield bodies 2 and 3 are removed and moved to the erector supports 46 and 48 in front, and the rear erector Supports 47 and 49 are removed. At the same time, the propulsion jacks 54, 55 installed at the rear of the single circular shield bodies 2, 3 are also moved forward. Then, the single circular segments 8 and 9 shown in FIG. 1 are assembled in the newly created segment assembling spaces in the single circular shield bodies 2 and 3 and connected to the left and right circular portions 7b and 7c of the existing overlapping circular segment. . Prior to this, reinforcement work necessary for connection with the single circular segments 8 and 9 is performed on the overlapping circular segment 7 side.

Complete the connection of the segments, the single circular shield body 2,
After cutting the welds 56 and 57 that fixed the 3 to the multiple shield body 1, the propulsion jacks 54 and 55 were extended, and the newly assembled single circular segments 8 and 9 were used as the reaction force receiving single circular segments. By propelling the shield bodies 2 and 3 underground, branch excavation is started.

FIG. 13 to FIG. 17 show another example of the operation procedure for shifting from overlapping circular excavation to single circular excavation. Figures 13 and 14
The figure shows the state when the overlapping circular excavation is performed. The single circular shield body 2, 3 is stored in the multiple shield body 1 so that both tail skin plates 51, 52, 53 overlap, and the single circular shield By providing notches 52a and 53a on one side of the tail skin plates 52 and 53 of the main bodies 2 and 3, an assembly space for the overlapping circular segment 7 is secured in the tail portions of both shield main bodies. Assembly of the overlapping circular segment 7 is performed by two erectors mounted on erector supports 47 and 49 in the single circular shield bodies 2 and 3. As described above, the use of the erector 60 shown in FIGS. 18 and 19 allows the assembly of overlapping circular segments with two erectors.

When transitioning from overlapping circular excavation to single circular excavation, the welding portions 56 and 57 that fixed the single circular shield bodies 2 and 3 to the multiple shield main body 1 are cut, and the single circular shield main body is cut.
The propulsion jacks 54, 55 provided for the protruding jacks 54, 55 allow the single circular shield bodies 2, 3 to be separated from the multiple shield body 1 by a predetermined distance (the rear ends of the tail skin plates 52, 53 have the existing overlapping circular segments 7). 17), and at the advanced position, the arc-shaped additional tail skin plates 58, 59 as shown in FIG.
52a and 53a are additionally installed to compensate. FIGS. 15 and 16 show the state after the additional tail skin plates 58, 59 are attached. Then, in the segment assembly space newly created in the single circular shield bodies 2 and 3, the
Assemble single circular segments 8 and 9 connecting to the existing overlapping circular segments 7 using the erector attached to and 49, and use the single circular segments 8 and 9 as a reaction force receiving unit to form a single circular shield body 2, Start branch excavation by propelling 3 underground. In this case, since the erector is not installed in the central space 10 of the multiple shield main body 1, a sufficient working space for additional attachment of the tail skin plate and the like can be secured.

Next, a method of constructing a station tunnel and an inter-station tunnel on a subway using the multiple shield machine according to the present invention will be described.

As shown in FIG. 20 (plan view), the multiple shield excavator 81 of the present invention is inserted into the ground from the starting shaft 80, and an overlapping circular excavation of the station tunnel planned space L1 is performed first. At the branching point where is completed, the above-mentioned transition work to the single circular excavation is performed, and the branch excavation by the single circular shield bodies 2 and 3 is started. Then, a single circular excavation of the station-to-station tunnel scheduled section L2 is performed on the extension of the existing excavation line. It will be buried and killed in the ground at the branch point of the multiple shield body 1.

As shown in Fig. 21, the triple circular shield tunnel 38 constructed as a station tunnel needs to be cut and expanded with the center part as the space 83 for the station building and both sides as the space 84,85 for the rails. The entire section can be used effectively without
The single circular shield tunnels 86 and 87 between the stations shown in the figure can be used as single-track parallel rail tunnels without extra space. In both figures, 88 indicates a station platform and 89 indicates a rail.

In this case, the interval, line shape, and the like of the tunnel between the stations can be arbitrarily selected. In addition, the first cutter head, which is responsible for only excavating a station tunnel having a shorter excavation distance than the inter-station tunnel, employs an oscillating excavation type cutter head to have an excavating capacity corresponding to the excavation distance, or to remove soil. Economicalization can be achieved by consolidating equipment such as devices and erectors.

In the above description, an example in which two single circular shield bodies are housed in a multiple shield body having three overlapping cylindrical parts has been described. Regarding the number of stored shield bodies,
It can be increased or decreased as appropriate depending on the scale of the station, location conditions, and the like. 23 and 24 show two overlapping cylindrical portions 91a and 91b.
A fourth embodiment of the present invention is shown in which a single circular shield main body 92 is stored in a multiple shield main body 91 having. Although not shown, four or more overlapping cylindrical portions of the multiple shield main body can be arranged in parallel.

Further, in the above description, an example of a subway has been given as an application field of the present invention, but the present invention can also be applied to other fields such as an underground road.

〔The invention's effect〕

According to the first aspect of the present invention, a single circular shield main body stored in the multiple shield main body is separated at an arbitrary point and branched and excavated, so that an excavated cross section can be shifted from an overlapping circular shape to a single circular shape. In addition, it is possible to build a continuous circular shield tunnel that requires no additional construction and a single circular shield tunnel that does not require an extra excavation part, starting from one shaft, so that the tunnel between the station and the tunnel between stations can be continuously constructed. Such shield tunnels having different forms can be continuously constructed economically and in a short period of time.
In addition, as described above, since branch excavation can be performed without exposing the ground, the safety of construction is high.

According to the second aspect of the present invention, since the first cutter head supported by the multiple shield main body is shaped so as not to interfere with the single circular shield main body at the start of branch excavation, the overlapping circular excavation is changed to the single circular excavation. At the time of the shift, dangerous work such as going out to the ground and cutting the cutter head becomes unnecessary.

According to the third aspect of the present invention, the cutter heads can be arranged in substantially the same plane while preventing mutual interference between the first and second cutter heads, and the stability of the face can be ensured. With the combination of the rocking excavation type cutter head and the rocking excavation type cutter head, it is possible to provide an excavating ability corresponding to each excavation distance, which is economical.

According to the fourth aspect of the present invention, the excavated soil by the first cutter head is guided to the earth discharging device in the single circular shield body arranged adjacently by the earth and sand guide, so that the earth discharging equipment is concentrated and the rear equipment is installed. Can be simplified, and a work space for segment assembly and the like can be widened.

According to the fifth aspect of the present invention, by moving the erector in the single circular shield body forward at the branch point, the tail skin plate can be completed in advance in the single circular shield body, and the single circular excavation can be performed. Migration work becomes easy.

According to the sixth aspect of the present invention, only the single circular shield main body is advanced at the branch point by a predetermined distance, so that the tail skin plate of the single circular shield main body can be additionally attached without exposing the ground, and the work safety is improved. Nature can be secured.

[Brief description of the drawings]

1 is a plan view showing a state immediately after the start of branch excavation of the multiple shield excavator according to the present invention, FIG. 2 is a front view showing an assembled state of the overlapping circular segments, and FIG. 3 is a multiple shield excavator according to the present invention. FIG. 4 is a sectional view taken along line AA of FIG. 3, FIG. 5 is a sectional view taken along line BB of FIG. 4, and FIG.
FIG. 7 is a sectional view of an essential part of an earth pressure shield shown as an example of a shield type, FIG. 7 is a sectional view of an essential part of a muddy shield similarly, and FIG. 8 is a second embodiment of a multiple shield excavator according to the present invention. FIG. 9 is a cross-sectional view taken along the line CC of FIG. 8, FIG. 10 is a front view of a third embodiment of the multiple shield excavator according to the present invention, and FIG. Plan view of a multiple shield excavator showing an example of the procedure for shifting to
FIG. 13 is a cross-sectional view taken along the line DD of FIG. 11, FIG. 13 is a plan view of a main portion of a multiple shield excavator showing another example of the above-mentioned transition procedure, FIG.
13 is a cross-sectional view taken along the line EE of FIG. 13, FIG. 15 is a plan view of an essential part showing a state after the tail skin plate is additionally attached to the multiple shield excavator of FIG. 13, and FIG. FF sectional view,
FIG. 17 is a perspective view of an additional tail skin plate, FIG. 18 is a cut-away side view of the erector, FIG. 19 is a view taken along the line GG of FIG. 18, and FIG. 20 is a multiple shield excavator of the present invention. Station state tunnel and station-to-station tunnel construction state explanatory diagram, FIG. 21,
FIG. 22 is a cross-sectional view of a station tunnel and a tunnel between stations, respectively. FIG. 23 is a front view of a fourth embodiment of a multiple shield excavator according to the present invention, FIG. 24 is a plan view of the same, and FIG. FIG. 26 is a plan view of an essential part of the reference example, FIG. 27 is a cross-sectional view taken along line HH of FIG. 26, and FIG. FIG. 29 is an excavated sectional view of the reference example. 1,91 ... multiple shield body, 1a, 1b, 1c, 91a, 91b ... cylindrical part,
2,3,92 ... single circular shield body, 4 ... first cutter head, 5,6 ... second cutter head, 7 ... overlapping circular segment, 8,9 ... single circular segment, 35 ... drive device, 36: screw conveyor for earth removal, 38: mud pipe, 39: sand guide, 46-50: erector support, 54, 55: jack for propulsion, 58, 59: additional tail skin plate, 60: erector

Continuation of front page (72) Inventor Minoru Shiozaki 650, Kandachi-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. Tsuchiura Plant (56) References JP-A-3-247894 (JP, A) JP-A-1-268991 ( JP, A) JP-A-2-153196 (JP, A) JP-A-2-229396 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) E21D 9/06 301

Claims (6)

(57) [Claims] 1. A multiple shield body having an overlapping circular cross-sectional shape in which a plurality of cylindrical portions are connected in parallel with each other and adjacent cylindrical portions are partially overlapped with each other; A cylindrical single circular shield body stored in the multiple shield body so as to be on the same line with respect to some of the cylindrical portions, and a cutter head for excavating the front face of both shield bodies. And the cutter head comprises:
It comprises a first cutter head supported by the multiple shield main body and a second cutter head supported by the single circular shield main body, wherein the single circular shield main body includes the second cutter head. A driving device to be operated, an excavating device for discharging excavated earth and sand backward, an excavating equipment device including a propulsion jack and an erector are stored, and the excavating device device is configured to branch from the multiple shield body and excavate independently. ,
The propulsion jack is commonly used for multiple shield excavation and single excavation of a single circular shield body. 2. The first cutter head has a shape in which a part of an outer peripheral portion is cut out so as not to interfere with the single circular shield main body at the start of branch excavation. A multiple shield excavator that can branch. 3. The first and second cutter heads are arranged in parallel in substantially the same plane in front of the shield bodies,
Among them, only the second cutter head is a rotary excavation type cutter head, and the first cutter head has a shape in which an outer peripheral portion is partially cut out, and within a range that does not interfere with the second cutter head. 3. The multi-branch shield excavator according to claim 2, wherein the swinging excavation type cutter head swings. 4. The method according to claim 1, wherein the first cutter head is disposed forward of the second cutter head, and excavated earth and sand by the first cutter head is provided between the first cutter head and the multiple shield body. The multi-branch shield excavator according to claim 1 or 2, further comprising a sediment collecting guide for guiding to a soil removal device in the single circular shield body disposed adjacently. 5. A multiple shield excavator according to any one of claims 1 to 4, wherein an overlapped circular segment assembled in a tail portion of said multiple shield main body is propelled into the ground as a reaction force receiving, and is used for a predetermined section. After excavation of the overlapping circular section, the erector in the single circular shield main body is moved forward from the position at the time of assembling the overlapping circular segment, and is connected to the existing overlapping circular segment in the newly created segment assembling space. By assembling a single circular segment and using the single circular segment as a reaction force to propel the single circular shield body into the ground, a shield tunnel having a single circular cross section is built on the extension of the excavation line so far. A branch excavation method for a multiple shield excavator characterized by starting a branch excavation. 6. A multiple shield excavator according to any one of claims 1 to 4, wherein an overlapped circular segment assembled in a tail portion of said multiple shield main body is propelled into the ground as a reaction force receiver, and is used for a predetermined section. After digging the overlapping circular section, the single circular shield body is advanced a predetermined distance with respect to the multiple shield body, and a tail skin plate is added to the rear of the single circular shield body at the advanced position. By assembling a single circular segment to be attached and connecting to the existing overlapping circular segment in the newly created segment assembly space, and propelling the single circular shield body into the ground as a reaction force receiving the single circular segment. Of a multiple shield excavator characterized by starting a branch excavation to build a shield tunnel with a single circular section on the extension of the existing excavation line岐掘 Susumu way.