JP3010546B2 - Shield excavator and shield construction method using it - Google Patents

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 soil pressure from the ground surrounding a tunnel to be built varies depending on a place, 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 method, a segment forming an inner wall surface of the tunnel is assembled behind the shield excavator while excavating the ground. 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 to the tunnel from the surrounding ground, and accordingly, the outside of the shield excavator. The diameter is set. However, FIG.
As shown in the figure, along the direction in which the tunnel 1 extends, the surrounding ground G
In some cases, the magnitude of the soil pressure acting on the tunnel 1 varies depending on the location. In such a case, the lining thickness of the entire tunnel 1 is determined according to the maximum soil pressure generation position. It is common.

[0003]

However, the above-mentioned conventional shield method has the following problems. First, when the lining thickness of the tunnel 1 is determined according to the maximum soil pressure as described above, the tunnel 1 has an unnecessarily thick lining in a place where the soil water pressure is low, which is uneconomical. There is a problem that is.

In order to solve such a problem, as shown in FIG. 7, a tunnel 1 'is connected to a side A having a high soil water pressure and a side B having a low soil water pressure.
There is a method of changing the lining thickness. In this method, two types of shield excavators 2a having different outer diameters are used.
2b, the tunnels 1'a and 1'b are excavated on the high side A and low side B of the soil water pressure, respectively. By joining in the tunnel 3, a tunnel 1 'is constructed. However, in this method, a plurality of shield excavators 2a and 2b must be prepared, and the number of shafts to be built increases, so that there is a problem that equipment costs and construction costs increase significantly. In addition, this method is not practical when the place where the soil water pressure is high and the place where the soil pressure is low alternately continue because the cost is further increased for the above-mentioned reason.

As described above, in the conventional shield method, there is room for cost reduction when a tunnel is constructed in a place where the soil water pressure changes. The present invention has been made in consideration of the above points, and provides a shield excavator capable of economically constructing a tunnel even when soil 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 a tail portion of a skin plate forming an outer shell of the shield excavator, and a backing material is provided on the inner tail member. It is characterized in that a through-hole communicating with the front and rear in the excavation direction is formed 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 a third aspect of the present invention, when a tunnel is constructed by assembling segments on the inner peripheral wall of a hole excavated in the ground with a shield excavator, a tail portion of a skin plate forming an outer shell of the shield excavator. The inner tail member having an inner diameter smaller than that of the skin plate is configured to be removably attachable, and in a place where the soil water pressure from the surrounding ground is equal to or less than a predetermined reference, the inner tail member is attached to the tail. A segment having an outer diameter substantially 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 form a tunnel. And where the soil pressure from the surrounding ground is equal to or higher than a predetermined reference, the inner tail portion 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, an inner tail member is detachably provided inside the tail portion of the skin plate of the shield excavator, and a through hole is formed in the inner tail member for filling the backfill material. The configuration was adopted. Thereby, when the inner tail member is removed, a segment having an outer diameter substantially equal to 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 equal to the inner diameter of the inner tail member can be assembled. be able to. In this way, a single shield excavator can assemble segments with different outer diameters at different locations, thereby making it possible to change the lining thickness of the tunnel. Further, when assembling the segment 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.

According to the second aspect of the present invention, the inner tail member is configured to be circumferentially dividable. 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, the inner tail member can be easily attached and detached, and it is possible to cope with a case where the lining thickness is desired to be reduced after the portion having a large lining thickness of the tunnel is built.

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 attached to a 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 lower than a predetermined reference, the inner tail member is attached to the tail portion, and a segment having substantially the same outer diameter as the inner tail member is assembled. Build
In places where the soil pressure from the surrounding ground is higher than a predetermined reference, remove the inner tail member from the tail part, assemble a segment with an outer diameter approximately the same as the inner diameter of the tail part of the skin plate, and build a tunnel Configuration. In this way, by constructing a tunnel while attaching and detaching the inner tail member with one shield excavator, the tunnel is constructed by changing the lining thickness depending on the location according to 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 shape with a cross-sectional outer shape, and is provided with an excavation unit 12 for excavating the ground G on the front side in the excavation direction,
The rear side has a schematic configuration in which a skin plate 13 forming the outer shell is provided. In the skin plate 13, a driving device (not shown) for driving the excavating portion 12, a shearing-out device for discharging the excavated sediment backward, and a segment S constituting a 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.

The tail portion 13 of the skin plate 13
An inner tail (inner tail member) 15 having a substantially cylindrical shape and a constant 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 has a grout hole (through hole) 17 extending in parallel with the excavation direction of the shield excavator 11 and penetrating the tail member 16 back and forth. And FIG.
As shown in the figure, on the front side 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 are provided on the inner peripheral surface of the rear end of the inner tail 15.

The shield excavator 1 having such a configuration
1, when the inner tail 15 is attached to the tail portion 13a of the skin plate 13, the inner tail 15
(Hereinafter, referred to as a "thin segment") having an outer radius of curvature substantially equal to the radius of curvature of the inner peripheral surface of the segment S1.
To build a tunnel T. When the inner tail 15 is removed,
As shown in FIG. 4, a segment having an outer radius of curvature substantially equal to the inner radius of curvature of the skin plate 13 (hereinafter, referred to as a segment)
Called "thin segments". ) S2 is assembled to build a tunnel T.

Here, the thin segment S1 (see FIG. 2)
And the thicker segment S2 (see FIG. 4), only the outer radius of curvature is different, and the inner radius of curvature is set to be the same. Therefore, the tunnel T1 formed by assembling the thin segment S1 and the tunnel T2 formed by the thick segment S2 have the same inner diameter except for the outer diameter.

Next, the shield excavator 1 having such a configuration will be described.
The method of constructing the tunnel T using FIG. For example, when excavating the tunnel T from a portion where the soil pressure acting on the surrounding ground G is low to a portion where the soil 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 shaft not shown to a predetermined depth in the ground G, and the ground G is excavated by the excavation unit 12. Then, a hole H having substantially the same diameter as the outer diameter of the skin plate 13 of the shield excavator 11 is excavated in the ground G.

While excavating the hole H in this way,
In the skin plate 13 of the shield excavator 11, thin segments S1, S1,... Transported from a shaft (not shown) are assembled by a segment assembling apparatus (not shown). At the same time, by the grout injection mechanism (not shown), through the grout holes 17 shown in FIG.
, And between the inner peripheral wall surface of the hole H and the grout 18
Fill.

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

Then, as shown in FIG. 5, when the shield excavator 11 reaches the portion G2 where the soil 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,... Having the gradually increasing outer diameter, the excavation of the hole H is continued.

Then, while excavating the hole H in the excavation section 12, the thick segments S2, S2,... Are carried into the skin plate 13, and these are formed into a predetermined shape by a segment assembling apparatus (not shown). Assemble and build tunnel T2. Thus, the portion G2 where the soil pressure is high
In the above, a tunnel T2 is constructed using the thick segment S2.

Thereafter, when the shield excavator 11 reaches a portion (not shown) having a low soil pressure again, the tail members 16, 16,... Each tail member 16 is attached to the inner peripheral surface of the tail portion 13a of the
Refit. In the same manner as described above, the tunnel T is built by filling the grout 18 between the outer peripheral surface of the thin segment S1 and the inner peripheral surface of the hole H while assembling the thin segment S1. ing.

When the tunnel T is constructed as described above and the shield excavator 11 reaches the 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 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 provided at a place G1 where the soil water pressure from the ground G is low. Is attached, a thin segment S1 is assembled, a tunnel T1 with a small lining thickness is built, and at a place G2 where the soil pressure from the ground G is high, the inner tail 15 is removed, and a thick segment S2 is assembled to assemble the thick lining. It is configured to build a large tunnel T2. In this way, by changing the lining thickness of the tunnel T to be built in accordance with 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 above-described shield excavator 11, the inner tail 15 is detachably provided on the inner peripheral surface of the tail portion 13a of the skin plate 13, and the inner tail 15
And a grout hole 17 is formed on the substrate.
Thus, when the inner tail 15 is attached, the thin segments S1, S1,... Can be assembled to build a tunnel T with a small lining thickness, and when the inner tail 15 is removed, the thick segments S2, S1
By assembling 2, ..., a tunnel T having a large lining thickness can be constructed. In this manner, one shield excavator 11 can install the segments S1 and S2 having different thicknesses according to the level of the soil water pressure and change the lining thickness of the tunnel T. Equipment costs can be significantly reduced compared to conventional methods that require the use of excavators. 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
Subsidence of the ground G can be reliably prevented.

Furthermore, the inner tail 15 can be divided into a plurality of tail members 16, 16,... In the circumferential direction. This allows the inner tail 15 to be easily attached and detached, and also allows the inner tail 15 to be skinned even when it is desired to reduce the lining thickness after building a large lining thickness portion of the tunnel T with the thick segment S2. It can be easily mounted on the tail portion 13a of the plate 13. Therefore, even when the lining thickness of the tunnel T changes many times, it can be easily coped with, and the number of shafts to be installed can be reduced to reduce the construction cost.

In the above embodiment, the tunnel T
The example used was to increase the lining thickness in the middle of the excavation and then reduce it again.However, even if the lining thickness changes several times, the same effect can be obtained by performing the construction in the same manner as above. It goes without saying that you can do it. In addition, other than the inner tail 15 of the shield excavator 11, for example,
The configuration of other parts such as 2 is not limited, and the above configuration can be applied to any type of shield excavator. Furthermore, it is also possible to prepare inner tails 15 having a plurality of thicknesses and change the lining thickness of the tunnel T in more steps.

[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. It was configured to form a through hole.
Thus, by attaching and detaching the inner tail member, segments having different outer diameters can be assembled, and the lining thickness of the tunnel to be built can be changed. In this way, a single shield excavator can change the tunnel lining thickness according to the level of soil water pressure, so that compared to the conventional method that requires the use of multiple shield excavators In addition, equipment costs can be significantly reduced. In addition, 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 drilled by the shield excavator by the through hole formed in the inner tail member. In addition, the settlement of the ground can be reliably prevented.

According to the shield excavator of the second aspect,
The inner tail member is configured to be dividable in the circumferential direction. Thereby, 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 the large lining thickness of the tunnel is built. Accordingly, it is possible to cope with the case where the lining thickness of the tunnel changes many times, and it is possible to reduce the number of shafts to be installed and to reduce the construction cost.

According to the shield method of the third aspect, an inner tail member having an inner diameter smaller than the skin plate is detachably attached to the tail portion of the skin plate of the shield excavator, and the surrounding ground is provided. In places where the soil water pressure from is less than or equal to a predetermined standard, the inner tail member is attached to the tail part, and a segment having substantially the same diameter as the inner tail member is assembled. In places where the soil pressure from the surrounding ground is equal to or higher than a predetermined standard, the inner tail member is removed from the tail part, and a segment having the same diameter as the inner diameter of the tail part of the skin plate is assembled. The construction was to build a tunnel. In this way, by constructing a tunnel while attaching and detaching the inner tail member with one shield excavator, it is possible to construct a tunnel with a different lining thickness depending on the soil water pressure from the surrounding ground Can be
The tunnel can be made economical without waste according to the soil pressure.

[Brief description of the drawings]

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

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

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

FIG. 4 is an elevational sectional view showing a state where the inner tail member is removed.

FIG. 5 is a sectional elevational view showing a state where a segment having a large lining thickness is assembled by the shield excavator.

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

FIG. 7 is an elevational sectional view showing another example of a tunnel constructed by applying a conventional shield method.

[Explanation of symbols]

 Reference Signs List 11 shield excavator 13 skin plate 13a tail part 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

──────────────────────────────────────────────────続 き Continuing on the front page (72) Kazuo Miyazawa, 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Toshio Watanabe 1-2-3, Shibaura, Minato-ku, Tokyo Shimizu (72) Inventor Tetsuo Ikoma 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Corporation (72) Inventor Shinichi Nishimura 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Corporation (72) Inventor Katsumi Shimizu 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (58) Investigated field (Int. Cl. ⁷ , DB name) E21D 11/10 E21D 11 / 00

Claims (3)

(57) [Claims] An inner tail member having an inner diameter smaller than the inner diameter of the tail portion is detachably provided inside a tail portion of a skin plate forming an outer shell of the shield excavator. A shield excavator, wherein a through hole communicating with the front and rear in the excavation direction is formed to fill the backing 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 a circumferential direction. 3. When a tunnel is constructed by assembling a segment on an inner peripheral wall surface of a hole excavated in the ground by a shield excavator, a tail portion of a skin plate forming an outer shell of the shield excavator is provided with a lower portion than the skin plate. The inner tail member having a small inner diameter is configured to be removably attachable, and in a place where the soil water pressure from the surrounding ground is equal to or less than a predetermined reference, the inner tail member is attached to the tail portion, While assembling a segment having an outer diameter substantially the same as the inner diameter of the inner tail member, filling a backfill material between the segment and the excavated hole with a backfill means to construct a tunnel, In a place where the soil water pressure from the ground is equal to or higher than a predetermined reference, the inner tail member is 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.