JPH0639879B2 - Lining sealing method in cast-in-place lining shield method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing method for preventing water leakage between a skin plate and a concrete lining in a cast-in-place lining shield construction method.

[0002]

2. Description of the Related Art The cast-in-place lining shield method is used to drive a shield excavator between the inner peripheral surface of a skin plate constituting the outer shell of the shield excavator and a formwork installed inside the skin plate at the same time as the shield excavator is excavated. This is a construction method in which the lining is formed by pressing the installed concrete under high pressure.There is no need for backfilling injection process compared to conventional construction methods, there is no collapse of the tail void portion, and high strength is achieved by high pressure pressing. A uniform lining structure can be obtained.

In this construction method, the advance of the shield machine and the high-pressure pressing of concrete are performed by the jack provided on the inner peripheral portion of the skin plate, and the thrust is received by the press ring provided at the tip of the concrete placing surface. ing.

Therefore, the skin plate advances due to the reaction force of the jack and the placed concrete is compressed through the press ring. After that, the jack is reduced to remove the pressing pressure, and The formwork and press ring are set again in the front, and the concrete placing and the forward and high pressure press work of the shield machine are repeated again.

[0005]

However, when the advance / high pressure press work of the shield machine for one step is completed,
The concrete that has been cast in the state where the pressing pressure is removed, that is, the length at which the outer circumference of the concrete lining and the inner peripheral surface of the skin plate are joined, is shortened by the amount by which the skin plate is moved forward. Since it has been removed, a slight gap is likely to occur at the joint between the skin plate and the concrete lining. If the ground is permeable and the groundwater level is high, groundwater may flow through this gap into the shield mine, causing unexpected accidents and work stagnation.

The present invention has been made in view of the above problems, and easily secures the waterproof property between the skin plate and the concrete lining after removing the press pressure, and assembles the form and the press ring. An object of the present invention is to provide a lining sealing method capable of improving safety and workability when performing work or the like.

[0007]

In order to achieve the above object, the method of sealing a lining in the cast-in-place lining shield method of the present invention is a concrete pouring tip.
One or both of the inner periphery of the rear portion of the skin plate located on the side surface and the outer periphery of the front end portion of the formwork are, for example, hydraulic jacks,
Previously buried projections capable out collision in the radial direction by the moving means, after removal of the Da設pressed pressure of concrete, the
And it is characterized in the Turkey compress the con <br/> cleat lining radially by operating the moving means to project the projection.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. 1 (a), 1 (b), and 1 (c) are sectional views showing the construction sequence of the cast-in-place lining shield method to which the present invention is applied.

In the figure, a shield machine 1 is provided with a plurality of jacks 3 extending rearward on an inner peripheral portion of a cylindrical skin plate 2.

Also, on the inner periphery of the rear part of the skin plate 2,
A mold 4 having a length corresponding to the stroke length of the jack 3 is assembled in a tubular shape, and a press ring 5 is located between the skin plate 2 and the mold 4 so as to face the jack 3.

In this cast-in-place lining method, concrete C is poured through the concrete casting pipe 6 between the latest formwork 4 and the skin plate 2, as shown in FIG.

After the concrete C has been cast, a face is excavated by the shield machine 1 and the excavated earth and sand is discharged through the conveyors 8 and 9 provided in the shield machine 1 and the existing shield mine 7 behind it. When the jack 3 is extended, the shield machine 1 is moved forward by the stroke of the jack 3 due to the reaction force of the jack 3, as shown in FIG.

At the same time, the concrete C is pressed by the jack 3 via the press ring 5 to fill the tail void on the rear side of the skin plate 2 and form a high strength and uniform concrete lining C '.

Next, as shown in FIG. 1C, the concrete lining C'where the jack 3 is reduced and formed by casting.
The reinforcing bar 10 is arranged on the inner periphery of the skin plate 2 between the jack 3 and the jack 3, and a new form frame 4 is assembled inside the reinforcing bar 10 and a press ring 5 is installed. Installation preparation is complete.

By repeating the steps (a) to (c) in the figure, the shield excavation is sequentially performed.

Here, when the jack 3 shown in FIG. 1B is fully extended, the joint length between the cast concrete C, that is, the concrete lining C'and the skin plate 2 is extremely short. , Therefore (c)
In the process (1), since ground water easily leaks into the shield machine 1 from the joint between the skin plate 2 and the concrete C, the space between them is sealed by the method described below.

[0017] That is, as shown in FIG. 2, it has been pouring
On the outer periphery of the front end portion of the mold 4 located on the side surface of the front end of the concrete C , a projection 21 is provided in a groove 20 formed here in advance.
It is embedded so that it can project outward in the radial direction of the tunnel section.
There is . The groove 20 is a forward / backward movement provided inside the formwork 4.
It is connected to a hydraulic jack 22 as a step via a high pressure oil passage 23. The grooves 20 and the protrusions 21 are provided at a plurality of locations on the outer periphery of the mold 4, at least on the ceiling surface side, and in any case, the protrusions 21 are projected outward in the radial direction by driving the hydraulic jack 22. You can

Therefore, concrete C is poured and the press pressure is applied.
1C , after the removal, the projection 21 projects radially outward by driving the hydraulic jack 22 and compresses the placed concrete C, the force of which is the concrete C and the skin as indicated by the arrow. The force acts to strongly press the connection portion between the plate 2 and the plate 2. As a result, high watertightness at the joint is maintained.

FIG. 3 shows another embodiment of the present invention. In the figure, a plurality of grooves 30 are formed on the inner periphery of the rear portion of the skin plate 2.
A projection 31 capable of projecting toward the inner peripheral side is embedded in the groove 30, and the groove 30 is connected to a hydraulic jack 33 via a high pressure oil passage 32.

Also in this embodiment, the projection 31 projects radially outward and inward by driving the hydraulic jack 33 and presses the concrete C at the joint, so that sufficient watertightness can be obtained.

In each of the embodiments, the groove and the protrusion are provided on either one of the skin plate 2 and the form 4, but it is needless to say that they may be provided on both.

[0022]

As described above in detail with reference to the embodiments, according to the present invention, the watertightness of the joint between the skin plate and the concrete lining is maintained even after the press pressure is removed. It is possible to improve work safety and workability in tunnels by preventing gaps between them and increasing water blocking performance.

[Brief description of drawings]

FIG. 1 is a sectional view showing a construction sequence of a cast-in-place lining shield method to which the present invention is applied.

FIG. 2 is a partial sectional view showing an embodiment of the sealing method according to the present invention.

FIG. 3 is a partial cross-sectional view showing another embodiment of the sealing method according to the present invention.

[Explanation of symbols]

 1 shield machine 2 skin plate 3 jack 4 formwork 5 press ring 20,30 groove 21,31 projecting C concrete C'concrete lining

Claims (1)

[Claims] 1. A cast-in-place lining shield construction method in which concrete placed between a skin plate and a formwork of the shield machine is pressed at the same time when the shield machine is excavated. on one or both of the ingress of ground water to a lining of a seal method for preventing a tip portion outer periphery of the rear inner peripheral or formwork skin plate located hitting設先end side of the concrete from between Such as a jack
Previously buried projections capable out collision in the radial direction by moving means, after removal of the Da設pressed pressure of concrete, the
Sealing method of lining in place concrete lining shield method, wherein the benzalkonium compress the con <br/> cleat lining radially by operating the moving means to project the projection.