JP2003206690A - Structure and method for cut-off of mouth in shield tunneling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure and a method for cut-off of a mouth in a shield tunneling method, which can offer resistance to pressure for injecting a back-filling material and adequately exert a cut-off function. <P>SOLUTION: A segment 2, which is located at a peripheral edge 62 of an opening of the mouth 61 of an arrival shaft 6, is provided with a cut-off tool 3 which is protruded outward from a peripheral surface of the segment 2; and the peripheral edge 62 is cut-off from the side of the segment 2. The cut-off tool 3 is constituted in such a manner that many holding plates 30, which are circumferentially mounted on the peripheral surface of the segment 2, are extended toward the side of a shield machine 1 or in such a manner that many cut-off sheet piles 5, which are circumferentially split inside the segment 2, are protruded toward the peripheral edge 62. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wellhead water stop structure and a water stop method in a shield construction method, and more particularly to a wellhead water stop structure for stopping water between a segment located inside a wall surface of a reaching shaft and a reaching hole. And a method of stopping water.

[0002]

2. Description of the Related Art In the construction of tunnels such as water supply and sewer systems and subways by the shield method, a shield machine is excavated from a starting shaft to a reaching shaft. When the shield machine reaches the reaching shaft and penetrates the wall of the reaching shaft, a large amount of groundwater and earth and sand flow out from the penetration part (tunnel well mouth) into the reaching shaft. We need to take steps. Conventionally, when the shield machine a reaches the wall surface b1 of the reaching shaft b, the water stop implement such as a holding plate is circumferentially arranged so as to surround the portion of the wellhead c through which the shield machine a penetrates inside the wall surface b1. Water was stopped by attaching d (see Fig. 8). The water stop implement d is a shield machine a
Is an open-ended structure that penetrates the wall surface b1 of the reaching shaft b, is attached to the natural side so as to easily accept the approach, and projects toward the inside of the wall surface b1 by the hinge d2. The water stop implement d is squeezed with a wire e or the like and pressed against the shield machine a and the segment f. Shield machine a
When the water penetrates the wall surface b1 and enters the reaching shaft b, the inner peripheral edge (rubber packing d1) of the water stop d is brought into close contact with the outer shell of the shield machine a, and the inflow of groundwater and earth and sand into the reaching shaft b. To be prevented.

In the above-mentioned case, the shield machine a is buried in the reaching shaft b with its face exposed, but recently, the work of drawing the shield machine a into the reaching shaft b is increasing (Fig. 9). In this case, after the water stop implement d is brought into close contact with the outer shell of the shield machine a to stop the water between the shield machine a and the outer surface of the segment f having a diameter smaller than the outer diameter of the shield machine a. In order to stop the water close to the segment f by making it close to, it is necessary to narrow the water stop implement d in two steps with the wire e.

[0004]

The above-mentioned conventional method has the following problems. <B> Since the water stop device d is installed in a direction in which water or the like flows out and is easily opened by water pressure,
It could not withstand the injection pressure of the backfill material and opened, failing to exert a sufficient waterproof function. <B> As a result of not being able to exert the water-stop function, sediment will flow out along with the water, loosening the ground, and hindering tunnel construction. <C> Because the space at the wellhead c is small, the shield machine a
Until the U-turn or pulling up is completed, water stoppage work cannot be fully performed. <D> The work of narrowing the waterproofing device d in two steps with the wire e is
The work must be performed all at once, and not only a lot of manpower is required, but the work is difficult in some cases due to work in a narrow space, and the work may be incomplete.

[0005]

SUMMARY OF THE INVENTION The present invention has been conceived in view of the above-mentioned conventional problems, and is a wellhead stop in a shield construction method capable of withstanding an injection pressure of a backfill material and sufficiently exhibiting a water blocking function. An object is to provide a water structure and a water stopping method. Another object of the present invention is to provide a wellhead water-stop structure and a water-stop method in a shield construction method that can easily perform water-stopping work even if the space at the wellhead is small. The present invention is intended to achieve at least one of the above objects.

[0006]

In order to achieve the above-mentioned object, a wellhead water stop structure in the shield construction method of the present invention is a wellhead water stop construction in a shield construction method in which a shield machine penetrates a wall surface of a reaching shaft. In the structure, a segment located inside the wall surface of the reaching shaft is provided with a water stop that projects outward from the peripheral surface of the segment, and the water stop closes the opening of the arrival port of the reaching shaft. It is what

The water stop of the wellhead water stop structure in the shield construction method of the present invention is a holding plate which is circumferentially divided and attached to the peripheral surface of the segment, and the holding plate is attached to the shield machine side. It is characterized in that it is configured to be pushed and expanded toward.

Further, the water stop of the wellhead water stop structure in the shield construction method of the present invention is a water stop sheet pile which is circumferentially divided and attached inside the segment. It is characterized in that it is configured to project toward the peripheral edge of the opening.

Furthermore, the wellhead water stop method in the shield construction method of the present invention is the wellhead waterstop method of the shield construction method in which the shield machine penetrates through the wall surface of the reaching shaft, and the segment having the wellhead water stop structure is used. Then, the opening of the arrival port of the reaching shaft is closed by the water stop tool, and the water of the arrival port is stopped from the segment side.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 of the present invention will be described below with reference to the drawings.

<a> Overall configuration FIG. 1 shows a shield excavator (hereinafter referred to as a shield machine) 1 that has been excavating in the ground, enters a reach shaft 6 and is a segment 2 having a wellhead water stop structure. Is schematically shown in a state of being located at the wellhead 61. In addition, the reference numeral 20 is attached to the normal segment. The water stopper 3 projects from the peripheral surface of the segment 2 toward the peripheral edge 62 of the wellhead 61, and prevents groundwater and earth and sand from flowing into the reaching shaft 6 from the ground 7 around the wellhead 61 (Fig. 3 (b )reference). In addition, the shield machine 1 is a known one, and a cutter face attached to the front surface of a substantially cylindrical outer shell is rotated to propel while excavating the natural ground 7, and the excavated soil generated by this is launched to the rear. It discharges from the vertical shaft (not shown) to the ground and assembles a number of segments 20 on the excavated inner wall to construct a shield tunnel.

<B> Segment The segment 20 is used as a lining material in a tunnel pit, and is a concrete or steel divided body divided into several pieces. A pair of main girders 2 on the skin plate 21
2 and 22 are provided so as to face each other, and a plurality of vertical ribs 23 (see FIG. 6) are attached between the main girders 22 and 22 as necessary to form the segment 20. In the segment 20 configured in this way, the water stop implement 3 is provided on the peripheral surface of the segment 2 that is to be located at the wellhead 61.

<C> Water Stopper The water stopper 3 comprises a large number of pressing plates 30 and an inflatable and deflatable bag body 40 for opening and closing the pressing plates 30. Each holding plate 30
Is a strip of steel plate having the required elasticity, and the pressing plates 30 are arranged in an annular shape on the segment 2 so that both sides in the circumferential direction overlap each other as shown in FIG. 2 (a). Then, one end of the shield machine 1 side is rotatably attached by a hinge 33, and the other end is set in a free state (Fig. 3).
(See (a)).

The bag 40 is formed by forming a tube-like elastic material such as rubber that can be inflated by injecting a fluid 42 such as air, water, oil, mortar, and backfill injection material. The bag 40 is housed in the gap 8 between the pressing plate 30 and the skin plate 21, and the injection pipe 41 extending from a part of the bag 40 is inserted into the segment 2 and connected to a fluid supply device (not shown). By inflating the bag body 40, the bag body 40 pushes the pressing plate 30 to spread it. Since the pressing plate 30 is rotatable by the hinge 33, the pressing plate 30 is expanded toward the shield machine 1 by the expansion of the bag 40 so as to open the umbrella (FIG. 2 (b), FIG. 3 (b)
reference).

Even when the pressing plate 30 is expanded, the pressing plates 3 are arranged so that both sides in the circumferential direction overlap each other.
0 is superposed and attached so that groundwater and earth and sand do not flow in from the natural ground 7 side. Also, each pressing plate 30
If both sides in the circumferential direction overlap in the expanded state, the hinge 33 side may be continuous in the circumferential direction and the other end side may be divided in the circumferential direction to form a strip shape. Alternatively, two holding plates 30 may be stacked so that both sides in the circumferential direction are superposed. By pushing the holding plate 30 toward the shield machine 1 so as to open the umbrella, the holding plate 30 is moved to the wellhead 61.
Close to the peripheral edge 62 of the opening of the
It will stop the water. Note that the holding plate 30 may be provided with rubber packing or the like to further improve the water blocking function.

Next, using the water shut-off device 3 of the present invention, a reaching shaft 6
A case of stopping the water at the wellhead 61 will be described.

<a> Assembly of a segment with a holding plate A holding plate 30 is attached to the divided body of the segment 2 which is to be located at the well 61 of the wall surface 60 of the reaching shaft 6.
When assembled, make a segment with a wellhead water stop structure (hereinafter referred to as a segment with a holding plate) 2. The shield machine 1 digging into the ground approaches the vicinity of the side face of the well 61 of the reaching shaft 6, and the tip of the shield machine 1 further penetrates the hole 61 and enters the reaching shaft 6, The segment 2 to be assembled is the opening peripheral edge 62 of the wellhead 61.
Assemble the segment 2 with the holding plate when it is positioned at. When the tip of the shield machine 1 penetrates the well 61 and enters the reaching shaft 6, a conventional holding plate is attached to the side of the well 61 to open the outer shell of the shield machine 1 and the opening of the well 61. It is also possible to seal the gap with the peripheral edge 62.

<B> After the assembly of the water stop pressing plate segment 2 by the pressing plate is completed, the shield machine 1 is propelled again and the bag 40 is filled with the injection pipe 41.
Inject air or water to swell. When the bag body 40 built into the outer periphery of the skin plate 21 swells, each holding plate 30 spreads out so that the umbrella opens with the hinge 33 as a fulcrum, and closes to the peripheral edge 62 of the opening of the wellhead 61. Seal between 7 and stop water. The direction in which the holding plate 30 expands is a direction that resists the outflow of groundwater and earth and sand,
The water stop function is improved. At the time when the holding plate 30 and the opening peripheral edge 62 of the wellhead 61 come into contact with each other, the backfilling material is injected from the segment 20 on the side of the wellhole 61 to stop the water from reaching the wellhead.

In the conventional method of stopping water from the reaching shaft 6 side,
In order for the shield machine 1 to enter the reaching shaft 6, the pressing plate had to be set in the opposite direction to the water stop direction (pressing direction), but according to the present invention, from the segment 2 side. Since it was designed to stop water at the well 61 of the reaching shaft 6,
The holding plate 30 can be attached in a direction that resists the outflow direction of groundwater and earth and sand, and the reaching shaft 6 and the shield machine 1
Regardless of the state, good water stopping performance can be secured.

[0020]

Embodiment 2 of the Invention As described above, the pressing plate 30 is attached to the bag body 40.
Although the umbrella is pushed and expanded toward the shield machine 1 by bulging, the holding plate 30 may be expanded by pushing the tie rod 34 out of the shield pit as described in the present embodiment. Good (see Figure 4).

One end of the pressing plate 30 is rotatably fixed to the skin plate 21 by a hinge 33, and one end of a tie rod 34 is connected to the other free end. Tie rod 34
Has a male screw 35 formed on the outer periphery and is screwed with a female screw of the bearing 24 provided on the skin plate 21. The handle 36 provided on the other end of the tie rod 34 is rotated to move the tie rod 34 along the lead of the screw 35, and the pressing plate 30 is pushed up. Also in this example, each holding plate 30 pushes and spreads so that the umbrella opens using the hinge 33 as a fulcrum, and closes to the peripheral edge 62 of the opening portion of the wellhead 61 to seal between the natural ground 7 and stop water. Holding plate 30
The direction of expansion is that which resists the outflow of groundwater and sediment, improving the water stop function.

[0022]

[Third Embodiment of the Invention] The pressing plate 30 may be expanded while being pulled by the wire 37 from the shield machine 1 as it is propelled (see FIG. 5). One end of the holding plate 30 is rotatably fixed on the skin plate 20 by a hinge 33, the other end is free, and the wire fitting 38 is attached to the outside of the holding plate 30.
To provide. The wire 37 is fixed to the wire fitting 38, and the other end of the wire 37 is fixed to the shield machine 1. Since the wire 37 is pulled by the shield machine 1 propelling the wire, the holding plate 30 spreads through the wire 37. Also in this example, each pressing plate 30 spreads out so that the umbrella opens with the hinge 33 as a fulcrum, and closely contacts with the opening peripheral edge 62 of the wellhead 61.
Seal the space between them and stop the water. The pressing plate 30 extends in a direction that resists the outflow of groundwater and earth and sand, and the water stop function is improved.

[0023]

Fourth Embodiment of the Invention As described above, the segment 2 is not required to have the structure in which the pressing plate 30 is expanded.
A plurality of water stop sheet pile windows 25 may be opened on the outer periphery of the skin plate 21, and the strip-shaped water stop sheet piles 5 may be projected outward from the windows 25 in the radial direction of the segment 2 ( (See FIG. 6). A lid 2 that can remove the water-stop sheet-pile window 25
Block with 6.

In this example, a plurality of water stop sheet piles 5 are connected to the segment 2.
In order to be able to be housed inside, the location of the main girder 22 at the end of the segment 2 on the arrival side has a structure with a guide groove 27 into which the water stop sheet pile 5 can be inserted. The guide groove 27 can determine the directionality of the water stop sheet pile 5, and can take the reaction force of the injection pressure of the backfill material and the soil water pressure. The water stop sheet pile 5 is configured to be pushed out from the inside of the shield pit by, for example, a hydraulic jack, human power, or another existing mechanical method. A large number of water stop sheet piles 5 are housed in the guide groove 27, and the water stop sheet pile segments 2 in which the water stop sheet piles 5 radially project outward in the circumferential direction are used as the segments to be located at the wellhead 61.

Next, description will be made on a case where the pit mouth 61 of the reaching shaft 6 is stopped by using the segment 2 with the water stop sheet pile of this embodiment. When the shield machine 1 enters the reaching shaft 6 and the segment 2 to be assembled next is located on the opening peripheral edge 62 of the wellhead 61, the segment 2 with water stop sheet pile is assembled. After the assembly of the segment 2 with the water-stop sheet pile is completed, the shield machine 1 is propelled again, and the water-stop sheet pile 5 is projected outward from the inside of the shield mine in the radial direction of the segment 2 by a hydraulic jack or the like to the peripheral edge portion 62 of the wellhead 61. Seal closely (see Figure 7). In the case of a rectangular shield, the waterproof sheet pile 50 for the corner is projected obliquely from the corner.
(See Figure 8). Since the projecting work of the water blocking sheet pile 5 can be performed from inside the shield pit, workability is improved, the water blocking effect is excellent, and the outflow of earth and sand or groundwater is prevented. When the water stop sheet pile 5 and the opening peripheral edge 62 of the wellhead 61 come into contact with each other, backfill material is injected from the segment 20 on the side of the wellhole 61 from 1 to 2,
Stop the water at the arrival pit work. The waterproof sheet pile 5 is sufficiently close to the peripheral edge portion 62 of the wellhead 61 by a hydraulic jack or the like.
A rubber packing may be joined to the (pressure side), or a bag such as a tube may be expanded.

The outer diameter of the rear segment 20 of the shield machine 1 is smaller than the outer diameter of the shield machine 1, and a step is formed between the shield machine 1 and the shield machine 1. In the conventional water stopping method, the water stopping tool is narrowed down to two stages. Although some work was required, according to the present invention, these problems are solved because the water stop tool (holding plate 30, water stop sheet pile 5) projects from the segment 2 side outward in the radial direction of the segment 2 to stop water. To do.

[0027]

Since the present invention is as described above, the following effects can be obtained. <B> Since the water is stopped from the reaching side from the segment side, the water stop can be attached in a direction that resists the direction in which groundwater and sediment flow out, regardless of the state of the reaching shaft or shield machine. It can exhibit good water-stopping performance. <B> Since the waterproofing equipment is installed in a direction that resists the direction in which groundwater and earth and sand flow out, the durability of the waterproofing function is improved, and the injection pressure of the backfill material also improves, resulting in sufficient injection. Backfill injection is possible with pressure. <C> Since the water stop is projected from the segment side to the outside in the radial direction of the segment to stop the water, there is no need to narrow down the water stop in two steps unlike the conventional water stop method.
Moreover, even if the space at the wellhead is small, the water stoppage work can be easily performed, and the workability is improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a relationship between a shield machine and a reaching shaft.

FIG. 2 is an explanatory view showing a segment with a holding plate of the present invention.

FIG. 3 is an explanatory view showing a relationship between a segment with a holding plate and a wellhead.

FIG. 4 is an explanatory view showing another embodiment.

FIG. 5 is an explanatory view showing another embodiment.

FIG. 6 is an explanatory view showing another embodiment.

FIG. 7 is an explanatory diagram showing a relationship between a segment with a water stop sheet pile and a wellhead.

FIG. 8 is an explanatory view showing a relationship between a segment with a water stop sheet pile and a wellhead.

FIG. 9 is an explanatory view showing a conventional water stopping method.

FIG. 10 is an explanatory view showing a conventional water stopping method.

[Explanation of symbols]

1 ... Shield machine 2 ・ ・ Segment equipped with wellhead water-stop structure 20 ... Segment 21: Skin plate 25 ... Window for still water sheet pile 27 ... Guide groove 3 ... Water stop 30 ... Presser plate 34 ... Tie rod 37 ... Wire 40 ... Bag 5 ... Water-stop sheet pile 50 ... Waterproof sheet pile 6 ... Delivery shaft 61 ... Wellhead 62 ... Opening peripheral edge 7 ... 8 ... Gap

Claims (4)

[Claims] 1. In a wellhead water stop structure of a shield construction method in which a shield machine penetrates a wall surface of a reaching shaft, a water stop projecting outward from a peripheral surface of the segment in a segment located inside the wall surface of the reaching shaft. And a water stoppage tool that closes the opening of the arrival opening of the reaching shaft, the wellhead water-stopping structure in the shield construction method. 2. A water stop of a wellhead water stop structure in a shield construction method according to claim 1, wherein the water stop is a press plate that is circumferentially divided and attached to a peripheral surface of the segment, and the press plate is a shield. A wellhead water stop structure in the shield construction method, which is characterized in that it is expanded toward the machine side. 3. A water stop of a wellhead water stop structure in the shield construction method according to claim 1, which is a water stop sheet pile that is circumferentially divided and installed inside the segment. A wellhead water-stop structure in a shield construction method, characterized in that it is configured to project toward the periphery of the opening of the reaching port. 4. A mine-hole water-stopping method of a shield construction method in which a shield machine penetrates a wall surface of a reaching shaft, wherein a segment provided with the pit-head water-stopping structure according to any one of claims 1 to 3 is used. A method for shutting down a wellhead in a shield construction method, characterized in that the waterstopper is used to block the opening portion of the reaching mouth of the reaching shaft to stop the reaching mouth from the segment side.