JPH01116192A - Method of curved excavation shield construction and machine thereof - Google Patents

Abstract

PURPOSE: To easily and accurately perform the curve excavation having the short radius by alternately repeating a process of excavating the front surface by a front surface cutter bit and a process of excavating the side surface by a side surface cutter bit simultaneously with front surface excavation. CONSTITUTION: A shield A is advanced by thrust of a jack 6 while a front face is excavated by a front surface cutter bit 5. Next, simultaneously with excavation of the front surface, the side surface excavation is performed by a side surface cutter bit 11, and thrust of the jack 6 is adjusted to advance the shield A while changing the direction. A process of the straight excavation and a process of changing the direction are combined and alternately performed so as to be conformed to the desired estimated passing passage.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a shield construction method and a machine for constructing a tunnel by propulsion of a shield (steel tube).

[Conventional technology]

Conventionally, in the shield construction method, the tunnel face is excavated using a front cutter bit that rotates at the front of the shield, the face is held and the shield is propelled by jack thrust, and the shield segments are assembled in the imagination created at the rear of the shield. The lining is completed, and backfill is injected between the lining segment and the ground. In the part where the shield's planned passage route is curved,
Among the many shield jacks arranged at equal intervals along the inner circumference of the shield, a plurality of shield jacks arranged on the outer half circumference in the curve direction are used to push the shield one-sidedly along the curve, The curved section is lined by appropriately combining odd-shaped segments and standard segments to accommodate the left-right unevenness that occurred at the rear of the shield.

To further describe the above curve progression, as shown in Fig. 1, in order for the shield a to curve, it requires a direction change, that is, a movement inside the curve S, but the cutter disk b The cutter bit on the front of the mount is shielded a.
Since only the front side of the curve S is excavated, an over-excavation device attached to the outer peripheral surface of the cutter disc b, that is, a copy cutter 〇, is generally used in combination to perform over-excavation to enlarge the excavation cross section to the inside of the curve S. , This allows it to change direction while moving forward.

[Problem that the invention seeks to solve]

The above-mentioned shield a has a ratio of outer diameter and length set within the required range, and especially when the length is a normal several meters, it can be used to move forward and change direction at the same time as described above. Propulsion of the shield a by the method described above cannot be carried out accurately unless the radius R of the curved portion of the planned passage route is as large as about 80 m.

In order to improve this, as shown in Fig. 2, the shield a was made into a one-stage center-fold type with the front and rear trunks a l + a t, which enabled propulsion on curved sections with a radius R of about 30 m. Furthermore, there is already a known shield machine that enables propulsion on a curved section with a radius of about 15 m by using a two-step folding type with a folding angle of 6 to 7° between the front, rear, and middle trunks al+a*, a3. It is being

However, in the case of these half-folding types, it is necessary to move forward at least several meters to reach the predetermined half-folding angle, so advance while making an angle from well before the starting point of the curve.
It is necessary to be able to obtain a predetermined mid-turn angle at the starting point of the curve, and as a result, the shield a follows a trajectory that deviates from the planned passage route.

Moreover, it would be a step forward to make the shield a into a folded type with three or four stages, for example, or to make the folding angle 10 degrees or more so that it is propelled along a curved section with a radius of 10 m or less. However, there are technical limitations in the method of changing direction, making it impossible.

Therefore, construction work on curved sections with relatively short radius R, ■ Cutting a shaft for changing the direction of the shield.

■ For sections where the shield cannot be curved, the open cut method will be used.

■ Workers excavate the space necessary to change the direction of the shield.

■ All curved parts are hand dug.

However, this method requires several months of construction time for each curved section.
This method does not use the shield method's (a) road surface, which has the disadvantage of requiring hundreds of millions of yen in construction costs. (b) Construction is fast. (C
) Costs for auxiliary methods such as ground improvement are low. (d) Workers are protected and safe by shields and existing segments. There are some disadvantages in not being able to take advantage of such benefits.

The object of the present invention is particularly that the radius R is 10 m or less, for example 8 m
To provide a curved shield construction method and machine that can easily perform construction on short curved sections of up to 6 m.

[Means for solving problems]

The configuration of the construction method of the present invention will be described below based on examples.

While excavating the front face of the face with the front cutter bit 5, the shield A is moved straight with a jack thrust, and at the same time as the front cutter bit 5 excavates the front side, the side cutter bit 11 performs side excavation, and the shield A is also made with a jack thrust. It consists of a step of changing the direction of A, and these two steps are alternately and repeatedly carried out.

In the above, the direction of shield A can be changed as necessary.
It is effective to prevent the inside of the shield A in the direction of bending from the existing segment G with a prevention device F.

Also, front cutter bit 5 and side cutter bit 11
may be driven by the same drive device or by different drive devices.

The configuration of the machine of the present invention will be described below based on an embodiment.

The shield A has a front cutter bit 5 mounted on a cutter disk C installed on the front side thereof and connected to a required drive device.
The shield A is equipped with a side cutter bit 1 on a cutter cylinder D rotatably fitted around the shield A.
1 is installed.

If the cutter cylinder D is rotated simultaneously by the same drive device B as the cutter disk C, a means for fixing or releasing the cutter cylinder D from the shield A is provided between the cutter cylinder D and the shield A. A means for connecting or disconnecting the cutter cylinder D to the cutter disk C is interposed between the cutter cylinder D and the cutter disk C.

These two means are collectively referred to as a fixed/rotating coupling device E in the embodiment.

On the other hand, the cutter cylinder D is connected to the cutter disk C.
Shield A is configured to be rotated by a separate drive device.
A dedicated drive device, ie, a torque motor 27, is installed inside the cutter cylinder separately from the drive device B, and is connected to the cutter cylinder D.

In the above, the shield A may be provided with a prevention device F that prevents the existing segment G from reaching the inside of the shield A in the direction of movement.

[Effect]

According to the construction method of the present invention, the shield travels in a curved direction by alternately going straight and changing direction, so unlike the conventional method, it is possible to construct curved sections with short radii. According to this, the construction can be carried out easily and accurately.

〔Example〕

First, a first embodiment of the shield machine of the present invention will be described in detail with reference to FIGS. 4 to 8.

A is a shield, which has a machine room 2 on the inside of the bulkhead l and a dirt room 3 on the outside. The machine room 2 is equipped with a drive device B consisting of a driving torque motor 4, etc., and a cutter disc C, which is rotated by the drive device B and equipped with a front cutter bit 5, etc., is installed on the front surface of the shield. There is. Further, the machine room 2 has a required plurality of shield jacks 6 arranged at equal intervals around its inner periphery.

D is a cutter cylinder, which has a bearing 8 and a dirt intrusion prevention seal 9 interposed on the outer periphery of the front half 7 to the shield, that is, the part where the shield A surrounds the machine room 2 and the dirt room 3. , are rotatably fitted.

This cutter cylinder D has its outer periphery flush with the tail plate or rear half 10 of the shield A, and is provided with a side cutter bit 11 on its outer periphery. 12 is a tail seal.

Normally, the cutter cylinder D is held in a fixed relationship with the shield 8, and becomes rotatable by releasing the fixed relationship as necessary. This is done using the drive device B.

Reference numeral E denotes a fixing/rotating coupling device for the cutter cylinder D, which consists of a flange 13 provided in the front end opening of the canter cylinder D, a fixing jack 14 installed around the dirt chamber 3 of the shield A, and the outer periphery of the cutter disk C. It consists of a connecting jack 15 installed in the section.

The flange 13 is located between the front end 7' of the shield A and the outer periphery C' of the cutter disk C, and has a required plurality of bottle receiving holes 16 arranged at equal intervals. The fixing jacks 14 are mounted on the bulkhead 1, and a plurality of fixed jacks are installed at predetermined intervals around the sediment chamber 3 using a stand 17, and the connecting jacks 15 are installed on the outer periphery C' of the cutter disk C. A plurality of pins are installed at predetermined intervals on the outer periphery C' through the holes 18, and the fixing pins 14' and connecting pins 15' are alternately opposed to the respective bottle receiving holes 16. .

That is, the fixed pins 14' of the fixed jack 14 face every other bottle receiving hole 16 arranged at equal intervals, and the connecting pins 15' of the connecting jack 15 face the fixed pins 1
4' is opposed to every other pin receiving hole 16 that is not opposed.

The fixing of the cutter cylinder D to the shield 8 is as follows:
This is done by inserting the fixing pin 14' into the opposing pin receiving hole 16 (Fig. 5), and also by inserting the cutter cylinder D.
is connected to the cutter disk C by inserting the connecting pin 15' into the opposing pin receiving bid 16 (FIG. 6).

19 is the tail plate of shield A, that is, the rear half 1
0, and a plurality of mud-making soil materials or mud-feeding water inlets are appropriately opened near the front half 7, and the well-known mud-making soil material or mud-feeding water inlets (not shown) provided on the cutter disc C. This is for pumping and injecting the required mud material or mud water through the piping 20.

Reference numeral 21 denotes a known earth discharge passageway that connects a receiving port to the earth and sand chamber 3 passing through the bulkhead 1 .

F is a tether installed between the existing segment G and the shield A so that when the shield machine moves in a curve, the shield A changes direction smoothly and accurately without moving forward in the direction of the curve. The device consists of a tie rod 22 that locks to the shield A and a tie rod 24 that locks to a reinforcement 23 fixed to the existing segment I-G.

Construction of a tunnel by the machine of the first embodiment having the above configuration is performed as follows.

When the planned passage line is a straight line, the cutter cylinder D is fixed to the shield A by means of a fixed/rotating coupling device (Fig. 5), and the cutter disc C is connected to the torque motor in the same manner as in conventionally known shield machines. The tunnel face is excavated by the front cutter bit 5, and the entire machine is moved straight by the thrust of an appropriately selected shield jack 6 using the existing segment I-G as a reaction force. Afterwards, predetermined subsequent construction is performed, such as assembling a shield segment in the space created between the rear part of the shield A and the existing segment G.

If the planned route is a curve, first make the following preparations.

The cutter cylinder D and cutter disk C are connected to each other by means of a fixed/rotating connection device (FIG. 6). In this case, before releasing the fixed relationship between the canter disc C and the shield A, insert the connecting pin 15' into the opposing pin receiving hole 16.
After entering the above-mentioned connection relationship, the fixing pin 14
When the pin is removed from the pin receiving hole 16, a predetermined connection relationship can be easily obtained without adjusting the relative position.

A locking device F is installed between the inside of the shield A in the direction of bending and the existing segment G, and is locked to prevent the inside from moving forward. However, this tethering is done as necessary.

Thereafter, the drive device B rotates the cutter cylinder D together with the cutter disc C, and the front canter bit 5 excavates the face, while the side cutter bit 11
The circumferential surface, especially the inner circular surface in the direction of bending, is excavated, and the entire machine is excavated by the thrust of the shield jack 6 located on the outer half of the shield A in the direction of bending. Change direction along the curve of the planned route. In this case, by force-feeding appropriate soil material for cultivation from the soil material injection port 19, the side surface soil excavated by the side cutter bit 11 of the cutter cylinder D is fluidized, and the front cutter bit 5 of the cutter disk C fluidizes the soil. The soil is discharged through the soil discharge passage 21 together with the excavated front soil (which has been fluidized by the injection of mud material as is conventionally known).

As a result of the above-mentioned direction change, irregularly shaped segments or standard segments are assembled into the imaginary left-right unevenness created at the rear of the shield A, and other subsequent construction is performed.

In the same manner as described above, by repeating a relatively short distance of straight movement and the above-mentioned direction change, the machine is caused to curve along the curve of the planned passage route.

FIG. 8 is for explaining the progression of the song. This machine has an outer diameter of 4.0 m and a length of 4.6 m, and the curve radius R =
To move along the curve S of 8 m (this machine's tip trajectory R' = 8.944 m), it takes 30 c from the original position (solid line) A.
At the straight forward position (dotted line) after moving straight m, the angle required for direction change is θ-'' ■ Code - = 2.15° 2 x π x 8 In addition, the amount of movement of the tip of this machine at this time is 4 rn' Xtan 2.15' = O, 100m.

In addition, in the above, when the curve radius R = 6 m, the angle required for direction change is θ = 2.9° 2 x π x 6 The amount of movement of the tip of this machine is 4 m x tan 2.9 ' = 0.200m.

Next, a second embodiment of the shield machine of the present invention will be described with reference to FIGS. 9 to 11.

In this second embodiment, the rotation of the cutter cylinder is performed by each drive device separately from the rotation of the cutter disk. Therefore, there is a fixed/rotational connection device between the cutter cylinder and the cutter disk. This embodiment differs from the first embodiment in that it does not have an intervening structure, but the other configurations are the same. Therefore, the same parts will be denoted by the same reference numerals, the explanation will be omitted, and only the differences will be described.

The shield A and the cutter cylinder D rotatably fitted to the outer periphery of the front half 7 of the shield A and the cutter cylinder D, which is rotatably fitted to the outer periphery of the first half 7 of the shield A, are connected to the outer periphery groove 25 provided in the first half 7 of the shield A, and the cutter cylinder D rotatably fitted to the outer periphery of the first half 7 of the shield A. It is engaged with the flange 26 of cylinder D.

Reference numeral 27 indicates a plurality of torque motors, which are drive devices, arranged at equal intervals around the inside of the machine room 2 of the shield A.
8 is a pinion fixed to each output shaft, and each pinion 28 meshes with the inner rack 29 of the flange 26 through the bottom opening 30 of the outer groove 25.

The inner rack 29 of the flange 26 and the torque motor 2
By meshing with the pinion 28 of 7, the cutter cylinder D
The cutter cylinder D rotates as the torque motor 27 is driven; however, even if other external force is applied to the cutter cylinder D, the cutter cylinder D itself does not rotate.

In this way, rotating the cutter cylinder D with power from a separate system from that of the cutter disc C means that the cutter cylinder D and the cutter disc C are rotated as in the first embodiment.
Compared to connecting and rotating with the same power,
This has the advantage of reducing the need for considerations such as twisting of the cutter cylinder D, insufficient total torque, and strength of the connecting portion.

The construction of the tunnel by the machine of the second embodiment having such a configuration is carried out in the same manner as in the first embodiment, so the explanation thereof will be omitted to avoid duplication.

It should be noted that the cutter cylinder D of both of the above embodiments can be applied to the front body of a center-folding type shield, and the drive method of the cutter cylinder is not limited to the center shaft method of both of the above embodiments, but may also be an outer circumferential drive method, It is also clear that an intermediate support method or the like may be used, and the present invention is not limited to the above embodiments.

[Effects of the Invention] As is clear from the detailed description above, the construction method of the present invention alternately moves the shield in a straight line and changes its direction. While performing frontal excavation, the direction change is performed simultaneously with the above-mentioned frontal excavation and side excavation using a side caster bit, making it possible to perform curved construction with a shorter radius than in the past.

According to the machine of the present invention, the above construction method can be carried out easily and accurately, and the structure is simple and manufacturing is easy.

The construction method and machine of the present invention are not only applicable to construction on curved sections, but also demonstrate their effectiveness in correcting unevenness and meandering.

[Brief explanation of the drawing]

Drawings 1 to 3 are explanatory diagrams of curved section construction in the conventional shield construction method, Figs. 4 to 8 show a first embodiment of the machine of the present invention, and Fig. 4 is a cross-sectional plan view; Figure 5 is a cross-sectional view of the main part showing the fixed state of the cutter cylinder and the shield, Figure 6 is a cross-sectional view of the main part showing the connected state of the cutter cylinder and cutter disk, and Figure 7 is a perspective view of the main part of the cutter cylinder. 8 is an explanatory diagram of the construction of a curved section by the machine of the first embodiment, and FIGS. 9 to 11 show a second embodiment of the machine of the present invention, and FIG. 9 is a cross-sectional plan view, FIG. 10 is a sectional view of the main part, and FIG. 11 is a sectional view of the main part. A...Shield, C...Canter disc, 5...Front cutter bit, D...
...Counter cylinder, 11...Side cutter bit, B...Driving device, E...Fixed/rotating coupling device, 4,27...Torque motor,
F: Locking device, G: Old: Existing segment. /1175 Figure O6 Figure O8

Claims (1)

[Claims] 1. The step of moving the shield in a straight line with the jack thrust while performing front excavation with the front cutter bit, and the step of moving the shield in a straight line with the jack thrust while simultaneously performing front excavation with the front cutter bit and side excavation with the side cutter bit. The curved cider construction method is characterized by a conversion process. 2. The curved shield construction method according to claim 1, wherein the direction change of the shield is performed by connecting the inner side of the shield in the curved direction to an existing segment. 3. The curved advance shield construction method according to claim 1 or 2, wherein the front cutter bit and the side cutter bit are driven by the same drive device. 4. The curved advance shield construction method according to claim 1 or 2, wherein the front cutter bit and the side cutter bit are driven by separate drive devices. 5. A shield machine comprising a movable front cutter bit on the front of the shield, and a movable side cutter bit on the side of the shield. 6. Attach the front cutter bit to the cutter disc installed in front of the shield and connected to the required drive device, and install the side cutter bit to the cutter cylinder rotatably fitted around the outer periphery of the shield. Stack,
A means for fixing or releasing the cutter cylinder from the shield, and a means for connecting or disconnecting the cutter cylinder from the cutter disk, respectively, between the cutter cylinder and the shield or between the cutter cylinder and the cutter disk. A shield machine characterized by being provided with. 7. Attach the front cutter bit to the cutter disc installed in front of the shield and connected to the required drive device, and install the side cutter bit to the cutter cylinder rotatably fitted around the outer periphery of the shield. Stack,
The shield machine further comprises a drive device provided within the shield separately from the drive device and connected to the cutter cylinder. 8. The shield machine according to claim 5, 6, or 7, further comprising a locking device that locks the inside of the shield in the direction of bending to an existing segment.