JPH08232581A - Shield machine and shield construction method using the same - Google Patents

Abstract

PURPOSE: To construct a tunnel economically even when earth-water pressure is different. CONSTITUTION: An inner tail is removably mounted on a tail 13a of a skin plate 13 of a shield excavator 11 in structure. In a location G1 where earth-water pressure from a ground G is low, the inner tail 15 is mounted and thin segments S1 are assembled, thereby constructing a tunnel T1 having a small lining thickness. In a site where the earth-water pressure from the ground G is higher, the inner tail 15 is removed and thick segments are assembled, thereby constructing a tunnel having a large lining thickness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield excavator suitable for use when the soil water pressure from the ground around a tunnel to be built changes depending on the location and a shield construction method using the same.

[0002]

2. Description of the Related Art As is well known, when constructing a tunnel using a shield construction method, a segment constituting an inner wall surface of the tunnel is assembled on the rear side of the ground while excavating the ground with a shield excavator. At this time, the lining thickness of the tunnel and the thickness of the segment are determined based on the inner diameter required for the tunnel to be built and the soil water pressure applied from the surrounding ground to the tunnel. The diameter is set. However, FIG.
As shown in, the surrounding ground G is changed along the extending direction of the tunnel 1 due to changes in the installation depth and the geology of the tunnel 1.
The magnitude of earth pressure acting on the tunnel 1 may vary depending on the location. In such a case, the lining thickness of the entire tunnel 1 is determined according to the maximum earth pressure generation position. Is common.

[0003]

However, the conventional shield construction method as described above has the following problems. First, if the lining thickness of the tunnel 1 is determined in accordance with the maximum earth pressure as described above, the tunnel 1 will have an unnecessarily large lining thickness in a place where the earth pressure is low. There is a problem that is.

In order to solve such a problem, as shown in FIG. 7, the tunnel 1'is provided with a side A having a high earth pressure and a side B having a low earth pressure.
There is a construction method that is classified into and, and the lining thickness is changed. In this construction method, two types of shield excavators 2a having different outer diameters,
2b is used to excavate tunnels 1'a and 1'b on the side A and the side B where the soil water pressure is high, respectively, and finally both tunnels 1'a and 1'b are excavated in the ground G or vertical shaft. The tunnel 1 ′ is constructed by joining inside the tunnel 3. However, in this construction method, a plurality of shield excavators 2a and 2b must be prepared, and the number of vertical shafts to be built also increases, so that there is a problem that equipment costs and construction costs increase significantly. Moreover, this method is not realistic because the cost is further increased for the above-mentioned reason when the place where the soil water pressure is high and the place where the soil water pressure is low are alternately continuous.

As described above, in the conventional shield construction method, there is room for cost reduction in the case of constructing a tunnel at a place where soil water pressure changes. The present invention has been made in view of the above points, and provides a shield excavator capable of economically constructing a tunnel even when soil water pressure is different, and a shield construction method using the same. With the goal.

[0006]

The invention according to claim 1 is
An inner tail member having an inner diameter smaller than the inner diameter of the tail portion is detachably provided inside the tail portion of the skin plate that forms the outer shell of the shield excavator, and the inner tail member is provided with a backing material. It is characterized in that through holes are formed so as to communicate with each other in the front-rear direction in the excavation direction for filling.

According to a second aspect of the present invention, in the shield excavator according to the first aspect, the inner tail member is configured to be divided into a plurality of pieces in the circumferential direction.

According to the third aspect of the present invention, when a tunnel is constructed by assembling segments on the inner peripheral wall surface of the hole excavated in the ground by the shield excavator, the tail portion of the skin plate forming the outer shell of the shield excavator. The inner tail member having an inner diameter smaller than that of the skin plate is detachably attachable, and the inner tail member is attached to the tail at a place where the soil water pressure from the surrounding ground is below a predetermined standard. Part of the inner tail member to assemble a segment having an outer diameter substantially the same as the inner diameter of the inner tail member, and a backfill material is filled between the segment and the excavated hole by a backfill means to form a tunnel. The inner tail part at a place where the soil water pressure from the surrounding ground exceeds a predetermined standard. The removed from the tail section, is characterized in that said gradually assemble the segments having an outer diameter of an inner diameter substantially the same dimensions of the tail portion of the skin plate and construction of the tunnel.

[0009]

According to the first aspect of the present invention, the inner tail member is detachably provided inside the tail portion of the skin plate of the shield excavator, and the through hole for filling the backfill material is formed in the inner tail member. It was configured. With this, when the inner tail member is removed, a segment having an outer diameter substantially the same as the inner diameter of the skin plate can be assembled, and when the inner tail member is attached, a segment having an outer diameter substantially the same as the inner diameter of the inner tail member can be assembled. be able to. In this way, a single shield excavator can assemble segments having different outer diameters depending on the location, which makes it possible to change the lining thickness of the tunnel. Further, when the inner tail member is mounted and the segment is assembled, the backfill material can be filled between the outer peripheral surface of the segment and the hole excavated by the shield excavator by the through hole formed in the inner tail member.

According to the second aspect of the invention, the inner tail member is configured to be divided in the circumferential direction. This allows
Even during the excavation, the inner tail member can be carried in from the rear side of the shield excavator and attached to the tail portion, whereby a small-diameter segment can be assembled. In this way, it is possible to easily attach and detach the inner tail member, and it is also possible to deal with the case where it is desired to reduce the lining thickness after constructing a portion with a large lining thickness of the tunnel.

According to the third aspect of the present invention, an inner tail member having an inner diameter smaller than that of the skin plate is detachably attachable to the tail portion of the skin plate of the shield excavator, and soil from the surrounding ground is provided. At locations where the water pressure is below a predetermined standard, attach the inner tail member to the tail part, assemble a segment with an outer diameter approximately the same as the inner tail member, and fill the back filling material with the back filling means to fill the tunnel. Built,
At locations where the soil water pressure from the surrounding ground is above a predetermined standard, remove the inner tail member from the tail section and assemble a segment with an outer diameter approximately the same as the inner diameter of the tail section of the skin plate to build a tunnel. I went with the configuration. In this way, a tunnel excavator is constructed by attaching and detaching the inner tail member and constructing a tunnel by changing the lining thickness depending on the location depending on the earth pressure from the surrounding ground. It becomes possible.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings. FIG. 1 shows a tail portion of a shield excavator according to the present invention. As shown in FIG. 1, the shield excavator 11 has a cylindrical outer shape in cross section, and an excavation unit 12 for excavating the ground G is provided on the front side in the excavation direction.
On the rear side, a skin plate 13 forming an outer shell thereof is provided and has a schematic structure. Then, in the skin plate 13, a drive device (not shown) for driving the excavation portion 12, a slip-out device for discharging the excavated slit backward, and a segment S constituting the tunnel T to be built into a predetermined shape. A segment assembling device for assembling is provided.

As shown in FIG. 2, a plurality of tail seal members 14, 14, ... Are provided on the inner peripheral surface of the tail portion 13a of the skin plate 13.

Further, the tail portion 13 of the skin plate 13
An inner tail (inner tail member) 15 having a substantially cylindrical shape and a certain thickness is mounted inside a. As shown in FIG. 3, the inner tail 15 has a configuration in which a plurality of tail members 16, 16, ... Having the same cross-sectional shape are connected in the circumferential direction. As shown in FIG. 2, each tail member 16 is detachably attached to the inner peripheral surface of the skin plate 13 by a joining means such as a bolt.

Further, as shown in FIGS. 2 and 3, every other tail member 16, 16, ..
Each of these has a grout hole (through hole) 17 extending in parallel with the direction of advance of the shield excavator 11 and penetrating the tail member 16 back and forth. And FIG.
As shown in, in front of each grout hole 17,
A grout injection mechanism (not shown) for injecting the grout (backfill material) 18 to the rear side is connected.

A plurality of tail seal members 19, 19, ... Are provided on the inner peripheral surface of the rear end of the inner tail 15.

The shield excavator 1 having such a structure
In No. 1, when the inner tail 15 is attached to the tail portion 13a of the skin plate 13, the inner tail 15
A segment (hereinafter, referred to as a "thin segment") S1 having an outer radius of curvature substantially the same as the radius of curvature of the inner peripheral surface of
Is assembled and a tunnel T is constructed. When the inner tail 15 is removed,
As shown in FIG. 4, a segment having an outer radius of curvature substantially the same as the inner radius of curvature of the skin plate 13 (hereinafter, referred to as
It is called a "thin segment". ) S2 is assembled and the tunnel T is built.

Here, the thin segment S1 (see FIG. 2)
And the thick segment S2 (see FIG. 4) differ only in the outer radius of curvature and are set to have the same inner radius of curvature. Therefore, the tunnel T1 of the portion formed by assembling the thin segment S1 and the tunnel T2 of the portion formed by the thick segment S2 differ only in their outer diameters, but have the same inner diameter.

Next, the shield excavator 1 having the above structure.
A method of constructing the tunnel T will be described with reference to FIG. For example, when excavating the tunnel T from a portion where the soil water pressure acting from the surrounding ground G is low to a portion where the soil water pressure is high, as shown in FIG.
The inner tail 15 is attached to the tail portion 13a of the skin plate 13 of FIG. Then, the shield excavator 11 is lowered from a vertical shaft (not shown) to a predetermined depth in the ground G, and the ground G is excavated at the excavation unit 12. Then, in the ground G, a hole H having a diameter substantially the same as the outer diameter of the skin plate 13 of the shield excavator 11 is excavated.

While digging the hole H in this way,
In the skin plate 13 of the shield excavator 11, the thin segments S1, S1, ... Carried from a vertical shaft (not shown) are assembled by a segment assembly device (not shown). At the same time, by the grout injection mechanism (not shown), through the respective grout holes 17 shown in FIG.
Between 1, S1, ... and the inner peripheral wall surface of the hole H, the grout 18
To fill.

In this way, in the portion G1 where the soil water pressure is small, the tunnel T1 is constructed by using the thin segment S1.

Then, as shown in FIG. 5, when the shield excavator 11 reaches the portion G2 where the soil water pressure is high, the inner tail 15 is removed from the tail portion 13a of the skin plate 13 at that time. Next, the shield excavator 11 is advanced as it is, and the removed inner tail 15 is left.

Subsequently, after assembling the connecting segments S3, S3, ... whose outer diameter is gradually increased, the excavation of the hole H is continued.

After that, while excavating the hole H in the excavating portion 12, the thick segments S2, S2, ... Are carried into the skin plate 13 and formed into a predetermined shape by a segment assembling device (not shown). Assemble and build the tunnel T2. In this way, the part G2 where the soil water pressure is high
At, the tunnel T2 is built using the thick segment S2.

After that, when the shield excavator 11 reaches a portion (not shown) where the soil water pressure is low again, the tail members 16, 16, ... Each tail member 16 is attached to the inner peripheral surface of the tail portion 13a of the inner tail 15
Reattach. Then, in the same manner as described above, the tunnel T is constructed by assembling the thin segment S1 and filling the grout 18 between the outer peripheral surface of the thin segment S1 and the inner peripheral surface of the hole H. ing.

Then, when the tunnel T is constructed as described above and the shield excavator 11 reaches a vertical shaft (not shown) provided at the end point of the tunnel T, the tunnel T having a predetermined length is constructed. Complete.

In the shield construction method described above, the inner tail 15 is detachably attached to the tail portion 13a of the skin plate 13 of the shield excavator 11, and the inner tail 15 is placed at the place G1 where the soil water pressure is low. , A thin segment S1 is assembled to construct a tunnel T1 with a small lining thickness, and at a place G2 where the soil water pressure from the ground G is high, the inner tail 15 is removed and a thick segment S2 is assembled to assemble the lining thickness. It is constructed to build a large tunnel T2. In this way, by changing the lining thickness of the tunnel T to be built according to the earth pressure from the surrounding ground G, the tunnel T can be made economical without waste. Moreover,
Since this can be realized by one shield excavator 11, the design and construction cost can be suppressed.

In the shield excavator 11 described above, the inner tail 15 is detachably provided on the inner peripheral surface of the tail portion 13a of the skin plate 13.
The grout hole 17 is formed in the structure.
Thus, when the inner tail 15 is attached, the thin segments S1, S1, ... Can be assembled to construct the tunnel T having a small lining thickness, and when the inner tail 15 is removed, the thick segments S2, S1.
It is possible to assemble 2, ... to build a tunnel T with a large lining thickness. In this way, one shield excavator 11 can set the lining thickness of the tunnel T by installing the segments S1 and S2 having different thicknesses depending on the level of soil water pressure. Compared with the conventional method which has to use an excavator, the equipment cost can be significantly reduced. Further, as described above, since the grout holes 17, 17, ... Are formed in the inner tail 15, the grout 18 can be filled between the outer peripheral surface of the thin segments S1, S1 ,. So
It is possible to reliably prevent the subsidence of the ground G.

Further, the inner tail 15 is configured to be divided into a plurality of tail members 16, 16, ... In the circumferential direction. As a result, the inner tail 15 can be easily attached and detached, and the inner tail 15 can be skinned even when it is desired to reduce the lining thickness after constructing a large lining thickness portion of the tunnel T with the thick segment S2. It can be easily attached to the tail portion 13a of the plate 13. Therefore, even if the lining thickness of the tunnel T changes many times, this can be easily dealt with, and the construction cost can be suppressed by reducing the number of vertical shafts to be installed.

In the above embodiment, the tunnel T
The example in which the lining thickness was increased during the excavation and then decreased again was used, but even if the lining thickness changes many times, the same effect can be obtained by performing the same work as above. It goes without saying that you can do it. In addition to the inner tail 15 of the shield excavator 11, for example, the excavation unit 1
The configuration of the other parts such as 2 is not limited, and the above configuration can be applied to any type of shield excavator. Furthermore, it is possible to prepare the inner tail 15 having a plurality of types of thicknesses and change the lining thickness of the tunnel T in multiple stages.

[0031]

As described above, according to the shield excavator of the first aspect, the inner tail member is detachably provided inside the tail portion, and the inner tail member is filled with the backfill material. The through hole is formed.
Thus, by attaching and detaching the inner tail member, the segments having different outer diameters can be assembled, and the lining thickness of the tunnel to be built can be changed. In this way, with one shield excavator, the lining thickness of the tunnel can be changed according to the level of soil water pressure, so compared to the conventional method where multiple shield excavators must be used. , The equipment cost can be significantly reduced. Moreover, when the segment is installed by mounting the inner tail member, the backfill material can be filled between the outer peripheral surface of the segment and the hole excavated by the shield excavator by the through hole formed in the inner tail member. It is possible to reliably prevent the subsidence of the ground.

According to the shield excavator of claim 2,
The inner tail member is configured to be separable in the circumferential direction. Accordingly, the inner tail member can be easily attached and detached, and it is possible to easily cope with a case where the lining thickness is reduced after the portion having a large lining thickness of the tunnel is built. Therefore, it is possible to cope with the case where the lining thickness of the tunnel changes many times, and the construction cost can be suppressed by reducing the number of vertical shafts to be installed.

According to the shield construction method of the third aspect, an inner tail member having an inner diameter smaller than the skin plate is detachably attachable to the tail portion of the skin plate of the shield excavator, and the surrounding ground is provided. In a place where the soil water pressure from is below a predetermined standard, attach the inner tail member to the tail part, assemble a segment of approximately the same diameter as the inner tail member, and fill the back filling material with the back filling means. In the place where the soil water pressure from the surrounding ground exceeds a predetermined standard, remove the inner tail member from the tail part and assemble a segment with the same diameter as the inner diameter of the tail part of the skin plate. It was constructed to build a tunnel. In this way, a tunnel excavator can be constructed by attaching and detaching the inner tail member with one shield excavator to build a tunnel whose lining thickness varies depending on the location depending on the soil water pressure from the surrounding ground. Can
The tunnel can be economical without waste depending on the earth pressure.

[Brief description of drawings]

FIG. 1 is a view showing an example of a shield excavator according to the present invention and a shield construction method using the same, and is a vertical sectional view showing a state in which a segment having a small lining thickness is assembled.

FIG. 2 is a diagram showing a main part of the shield excavator,
It is an elevational sectional view showing the state where the inner tail member was attached.

FIG. 3 is a front sectional view of the shield excavator.

FIG. 4 is a vertical cross-sectional view showing a state in which the inner tail member is removed.

FIG. 5 is a vertical cross-sectional view showing a state in which a segment having a large lining thickness is assembled in the shield excavator.

FIG. 6 is a vertical sectional view showing an example of a tunnel constructed by applying a conventional shield method.

FIG. 7 is a vertical cross-sectional view showing another example of a tunnel constructed by applying a conventional shield construction method.

[Explanation of symbols]

 11 shield excavator 13 skin plate 13a tail 15 inner tail (inner tail member) 17 grout hole (through hole) 18 grout (backfill material) G ground H hole S, S1, S2 segment T, T1, T2 tunnel

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kazuo Miyazawa 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Toshio Watanabe 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction (72) Inventor Tetsuo Ikoma 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Shinichi Nishimura 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. ( 72) Inventor Katsumi Shimizu 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd.

Claims (3)

[Claims] 1. An inner tail member having an inner diameter smaller than the inner diameter of the tail portion is detachably provided inside the tail portion of a skin plate forming the outer shell of the shield excavator, and the inner tail member is attached to the inner tail member. A shield excavator characterized in that through holes are formed to communicate with the back and forth in the excavation direction so as to fill the backfill material. 2. The shield excavator according to claim 1, wherein the inner tail member is configured to be divided into a plurality of pieces in the circumferential direction. 3. When constructing a tunnel by assembling a segment on an inner peripheral wall surface of a hole excavated in the ground by a shield excavator, a skin plate forming an outer shell of the shield excavator has a tail portion more than the skin plate. The inner tail member having a small inner diameter is configured to be detachably attachable, and in a place where the soil water pressure from the surrounding ground is below a predetermined standard, the inner tail member is attached to the tail portion, Assembling a segment having an outer diameter approximately the same as the inner diameter of the inner tail member, and filling a backfill material between the segment and the excavated hole by a backfill means to build a tunnel, In a place where the soil water pressure from the ground is higher than a predetermined standard, remove the inner tail member from the tail portion. Disconnect Te, shield tunneling, characterized in that continue to construction a tunnel assembled segments having an outer diameter of an inner diameter substantially the same dimensions of the tail portion of the skin plate.