JP2001220991A - Water cut-off structure of entrance section in shield tunneling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water cut-off structure of an entrance section in a shield tunneling method capable of surely securing water cut-off ability with ease. SOLUTION: In an entrance section wherein a ring-like entrance packing is installed along the whole circumference of the aperture of a shaft wall through which a shield machine passes, and a presser plate is provided to presses the tip section of the entrance packing to make it follow the outer shell of the shield machine in the excavation direction, a recessed section is provided in the inner circumferential face of the entrance corresponding to the position where the projected section provided in the outer circumferential face of the shield machine passes, and elastic bodies are mounted to press the entrance packing against the both shoulder sections of the recessed section.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water stopping structure at an entrance in a shield method.

[0002]

2. Description of the Related Art Conventionally, when a shield excavator passes through an opening in a shaft shaft, groundwater, muddy water, earth and sand from the ground flow into the shaft through a gap between the opening and the shield excavator. Ring-shaped entrance packing is installed along the entire circumference of the opening, and when the shield excavator passes, the entrance packing is pressed in the excavation direction by the holding plate, and the outer surface of the shield excavator is A water stopping structure is used in which the gap between the opening and the shield machine is sealed by following contact. On the other hand, it is necessary to perform backfill injection in order to prevent a gap from being generated between the segment and the ground with the promotion of the shield machine. For this purpose, piping for backfill injection is arranged on the outer peripheral surface of the shield machine. When the convex part passes through the entrance packing, it is difficult for the entrance packing to completely adhere to both shoulders of the convex part, and a gap is generated, and there is a danger that groundwater, earth and sand, etc. will flow into the shaft from this gap. There is. In order to prevent such a danger, various measures have been taken such as covering the convex portion with an elastic member, or shaping the shape of the convex portion using a metal plate, a filler or the like.

[0003]

However, the water blocking structure of the entrance section in the above-mentioned conventional shield method has the following problems. <B> In order to enhance the adhesion between the entrance packing and the convex portion installed on the outer peripheral surface of the shield machine, if the outside of the convex portion is further covered with a protrusion such as an elastic member, the inside of the ground is required. In the excavation, it is necessary to perform an extra excavation corresponding to the amount of the protrusion, so that the excavation work is extremely uneconomical. <B> When the shaft of a high-strength concrete shaft is cut directly with a shield excavator and opened, the impact load and propulsion force at the time of excavation cause the elastic members and fillers installed on the outer peripheral surface of the shield excavator to chip or fall off. There was a case where groundwater infiltrated into the shaft from such a damaged part.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and is a shield capable of easily and surely securing water stoppage even at a portion having a convex portion on the outer peripheral surface of a shield machine. It is an object of the present invention to provide a waterproof structure at an entrance in a construction method.

[0005]

In order to achieve the above object, the present invention relates to a ring-shaped entrance packing installed along the entire periphery of an opening of a shaft wall through which a shield machine passes. A fixing plate for fixing the entrance packing and a pressing plate that follows the outer shell of the shield machine in the excavation direction, the entrance corresponding to the position where the convex portion installed on the outer peripheral surface of the shield machine passes. A concave portion provided on the inner peripheral surface of the entrance, and an elastic body that presses the entrance packing against both shoulders of the convex portion in the concave portion, wherein the water blocking structure of the entrance portion in the shield method, or the elastic member Is a water blocking structure of the entrance part in the shield method, characterized by being covered with a protective sheet.

[0006]

Embodiments of the present invention will be described below with reference to the drawings.

<A> Shield machine 1 As shown in FIG. 1, the shield excavator 1 has substantially the same configuration as a normal shield excavator, but a pipe 10 for backfill injection and a cover thereof are provided on the outer peripheral surface thereof so as to protrude in the excavation direction. A part 2 is formed. On both sides, Figure 2
The shoulder 3 is formed as shown in FIG.

<B> Configuration of the entrance section. As shown in FIG. 1 and FIG. 2, a recess 5 is provided in the opening 4 of the shaft in a direction of excavation corresponding to a position at which the protrusion 2 provided on the outer peripheral surface of the shield machine 1 passes. Two elastic members 6 are attached to the concave portion 5 corresponding to the positions of both shoulders of the convex portion 2. Further, a protective sheet 7 is attached to the surface of the elastic body 6. On the other hand, a ring-shaped entrance packing 8 is attached to the entire periphery of the opening 4 by tightening the holding plate 9 with a bolt or the like. A flap hardware 91 is attached to an end of the holding plate 9 by hinge connection.

<C> Recess 5 On the inner peripheral surface of the opening 4, a concave portion 5 corresponding to a position where the convex portion 2 passes is provided. The concave portion 5 is provided with the convex portion 2.
It is formed in advance in consideration of the dimensions of the elastic member 6 and the like.

<D> Elastic body 6. Two elastic bodies 6 are attached to the concave portions 5 corresponding to the positions of both shoulders 3 of the convex portions 2 respectively. This elastic body 6
Consists of a block of rubber or the like, one end face of which is fixed,
The other end surface is free, and the entrance packing 8 is resiliently moved to return from the compressed state to the original state.
Press outside. The size of the elastic body 6 is determined in advance by a required repulsion force or the like.

<E> Protective sheet 7. A protective sheet 7 is attached to the inner peripheral surface of the opening 4 along the digging direction so as to cover the surface of the elastic body 6. The protective sheet 7 prevents the elastic body 6 from falling off and moving, and does not prevent the repulsive force of the elastic body 6. Therefore, for example, it can be constituted by a rubber sheet or the like.
The dimensions of the protection sheet 7 are determined in advance according to the dimensions of the elastic body 6 and the like.

<F> Mounting method. The recess 5 is provided on the inner peripheral surface of the opening 4 through which the convex portion 2 installed on the outer peripheral surface of the shield machine passes. The two elastic members 6 are attached to the concave portions 5 in accordance with the positions of the shoulders 3 of the convex portions 2. Further, a protective sheet 7 for protecting the elastic body 6 is attached. Thereafter, a ring-shaped entrance packing 8 is fastened around the opening 4 with a holding plate 9 in the same manner as the conventional entrance portion. As a result, even in a portion where the convex portion 2 is present on the outer peripheral surface of the shield machine, a gap easily generated between the convex portion 2 and the entrance packing 8 can be sealed by the repulsive force of the elastic body 6 to secure water stoppage. it can.

[0013]

[Effect of the Invention] The water blocking structure of the entrance part in the shield method according to the present invention is as described above, and the following effects can be obtained. <B> Even if there is a protrusion on the outer peripheral surface of the shield machine, water can be reliably stopped by simply attaching a small number of elastic members in a form utilizing the conventional water stop structure of the entrance section. . <B> Since the repulsive force of the elastic member is used, even when the shape of the convex portion is complicated, it is possible to secure water stoppage. <C> Even if the temporary wall of the opening is made of high-strength concrete or the like, sufficient water stoppage can be ensured.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a water stopping structure of the present invention.

FIG. 2 is a front view of FIG. 1;

FIG. 3 is an enlarged view of a part of a use state of the present invention.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoichi Miura 1-25-1, Nishishinjuku, Shinjuku-ku, Tokyo Inside Taisei Construction Co., Ltd. (72) Inventor Nobuhiko Takayama 1-25-1, Nishishinjuku, Shinjuku-ku, Tokyo No. Taisei Construction Co., Ltd. (72) Inventor Takashi Takahashi 1-25-1, Nishi Shinjuku, Shinjuku-ku, Tokyo Taisei Construction Co., Ltd. (72) Takeshi Yamada 3--15-14, Miyasaka, Setagaya-ku, Tokyo F-term (Reference) 2D054 AC01 EA07 FA06

Claims (2)

[Claims] Claims: 1. A ring-shaped entrance packing installed along the entire periphery of an opening of a shaft wall through which a shield excavator passes, and the entrance packing is fixed, and is attached to the outer shell of the shield excavator in the excavation direction. A presser plate to be followed; and an entrance portion comprising: a concave portion provided on an inner peripheral surface of the entrance corresponding to a position where a convex portion provided on an outer peripheral surface of the shield machine passes, and the entrance packing is provided in the concave portion. The waterproof structure of an entrance part in a shield method, comprising an elastic body pressed against both shoulders of the convex part. 2. The waterproof structure of an entrance part in a shield method according to claim 1, wherein the elastic body is covered with a protective sheet.