JPH0230896A - Water stopper for shield machine - Google Patents

Abstract

PURPOSE:To enhance the reliability and economy of water stopping by a method in which packings provided to the periphery of prespring and the inner surface of the rear end of tail plate are concurrently or alternately operated according to operating methods of lining shield construction work. CONSTITUTION:A water-stop packing 9 is provided to the periphery of a prespring in an expandible and press force-adjustable manner for the inner surface of a tail plate 12. Also, a water-stop packing 16 is provided to the inner surface of the rear end of the plate 12 in an expandible and press force- adjustable manner for the periphery of an existing concrete 18. According to operating processes of a lining shield construction work to cover the wall of tunnel excavated by a shield machine with in-situ concrete, the packings 9 and 16 are concurrently or alternately used to prevent the intrusion of water from outside. Even in the ground of high groundwater pressure, highly reliable water stopping work can be attained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a water stop device in the cast-in-place lining shield construction method, and in particular provides a water stop device that is highly reliable even in ground with a high groundwater level. The applicable ground conditions for the cast-in-place lining shield method can be expanded, and an economical tunnel structure using the cast-in-place lining shield method can be provided even in ground conditions where the groundwater level is high.

[Conventional technology]

Conventionally, tunnel lining using segments has been carried out in ground with a high groundwater level, and there is no example of a cast-in-place lining shield method being implemented in ground with a high groundwater level. In other words, the current situation is that there is no suitable way to stop water in the tail part of a cast-in-place lining shield with high water pressure, and it is not used under such conditions. In general, with cast-in-place lining shields, it is necessary to create a space by moving the press ring closer to the face than the place where new concrete is to be poured.

This is the period when the water-resistance ability against water intrusion from the outside is at its lowest, and in this state, the concrete is stretched out, the press jack is stretched out, the end of the formwork is secured by the press ring, and the fresh concrete is poured in, followed by pressurization. It is something that does. In addition, as a water stop method in the cast-in-place lining shield construction method, for example, Japanese Patent Application Laid-Open No. 63-63
There are technologies disclosed in Japanese Patent Application Laid-open No. 896 and Japanese Patent Application Laid-open No. 63-147097, etc., but all of these are expected to have a water-shielding effect on the fresh concrete placed during the propulsion of the shield machine, and have not been successful. There are things I can't say.

[Problem that the invention seeks to solve]

Tunnel lining construction using segments, which has been carried out in the past, has had problems in that the production cost of the segments is high and the work time for assembling the segments and injecting backfilling is long.

In addition, in the above-mentioned disclosed technology, since a water-blocking effect is expected from fresh concrete that has not yet solidified when the shielding machine is propelled, there is a problem in that high reliability cannot be obtained in its water-blocking ability. The present invention has been made in view of the above-mentioned problems, and its purpose is to provide an economical tunnel structure using the cast-in-place lining shield construction method even in ground conditions where the groundwater level is high.

[Means for solving problems]

This invention uses a lining shield construction method in which a tunnel wall excavated by a shield machine is lined with cast-in-place concrete, and a tail plate is provided on the inner periphery of the rear end of the tail plate so that it can expand and contract with respect to the inner periphery and the pressing force can be freely adjusted. This problem has been solved by making it possible to prevent water from entering the shield machine from outside by using both water-stop packings simultaneously or alternately depending on the work process in the cast-in-place lining shield construction method. It is resolved.

[For production]

In the present invention, two water stop devices are used to improve the water resistance even during the working time when the water resistance is the smallest, and water is stopped by tightening the flannel concrete from the outside during the working time. At this time, the shielding machine was of course stopped, and reinforcing steel assembly, formwork assembly, and concrete MW work were being carried out. If the poured fresh concrete is then pressurized, the water-stopping ability of the tail section will be increased, but there is a possibility that underground water etc. may infiltrate from the outer periphery of the press ring or leakage of concrete, so as a countermeasure, a hydraulic jack built into the press ring is used. Deal with this problem by using a water stop device. After that, the shield machine will move forward while excavating the face, so if the water stop device at the tail section is left in operation, there is a risk that it will rub against the finished concrete and be damaged. The shield machine is moved forward after the water stop device is retracted and retracted. Of course, when the shield moves forward, the pressurizing work by the press jack and the water stop device built into the press ring remain in operation.

The effect of the above means will be explained as follows according to the work process of the cast-in-place lining shield construction method.

(1) When assembling reinforcing bars and formwork in areas where concrete is to be poured, the water-stop gasket provided on the inner periphery of the rear end of the tail plate is pressed against the outer periphery of existing concrete that has begun to harden, thereby preventing water from entering the shield machine from outside. Prevent intrusion.

(2) During concrete placement and pressurization work, as well as shield machine propulsion work, by pressing the water-stop gasket provided on the outer periphery of the press ring against the inner periphery of the tail plate, it is possible to prevent the Prevents muddy water from entering from the interface between fresh concrete and tail plate.

(3) When work inside the tunnel is suspended,
It is also possible to operate the above two types of water-stop gaskets at the same time to double prevent unexpected flooding.

〔Example〕

The configuration of the present invention is such that a press ring 3 having a box-shaped cross section that slides back and forth by a press jack 2 provided in a shielding machine 1 is attached to the rear end of the press jack 2.
A large number of holes 5 are bored at regular intervals in the outer peripheral side plate 4 of the press ring 3, and an oil jack 7 having a rod 6 protruding toward the outer circumference of the press ring 3 is inserted into the inside of the press ring 3 at the location where the holes 5 are located. The angle members 8 are divided into several pieces in the circumferential direction across the plurality of rods 6 and are attached to the tips of the plurality of rods 6, and the outer periphery of the plurality of angle members 8 is provided with an elastic endless shape. A water stop gasket 9 is attached thereto, an oil hose 10 is connected to the oil jack 7, and an elastic endless water stop gasket 11 is also attached to the inner periphery of the press ring 3. On the other hand, behind the tail plate 12 of the shield machine 1, an oil jack 14 having rods 13 protruding inward at regular intervals is provided around the entire circumference of the tail plate 12,
A metal fitting 15 is provided on the inner end of the rod 13, which is a flat plate-shaped packing receiver divided into a plurality of parts. It is formed by connecting hoses 17.

The construction of the present invention will be explained based on the above-mentioned configuration. After concrete pouring, oil is sent to the oil jack 7 provided inside the press ring 3 of the shielding machine l, and the rod 6
is made to protrude from the outer periphery of the press ring 3, and the water stop packing 9 is pressurized and pressed against the inner surface of the tail plate 12, and the poured fresh concrete 18 is pressurized by the press jack 2, and the shield machine 1 is propelled to remove the ground. dig. When the excavation is completed and the shield machine 1 has stopped, oil is sent to the oil jack 14 provided on the inner circumference near the rear end of the tail plate 12 of the shield machine 1, and the rod 13 of the oil jack 14 is moved in the inner direction of the tail plate 12. Pressure is applied to press the extruded water stop packing 16 against the outer periphery of the existing concrete 18, and the rod 6 is contracted to release the pressing force of the water stop packing 9 to the tail plate 12.

Next, the pull ring 3 is pulled back to the face side to construct a working space, the reinforcing bars and the formwork are set in a predetermined position, and then the press ring 3 is set in a predetermined position by the press jack 2. Thereafter, the process of activating the water stopper 9 again by the oil jack 7 and pressing it against the inner surface of the tail plate 12, releasing the operation of the water stopper 16, and pouring concrete is repeated. As described above, water intrusion from the outside of the shield machine 1 is prevented by operating the water stop gaskets 9 and 16 according to the work process of the cast-in-place lining shield method.

Although FIG. 1 shows an embodiment of the muddy water type cast-in-place lining shield construction method, the present invention is not only applicable to the muddy water type shield construction method, but can also be applied to the earth pressure type shield construction method.

In addition, the excavation is propelled by driving the swing motor 26 to drive the cutter 1.
9, excavation is carried out, and the propulsion jack 24 takes a reaction force to the formwork 25, propels the shield machine l, and feeds mud from the mud feeding pipe 21 to the partition wall 23. While pressurizing the inside of the partition wall 23, the excavated soil is pumped through the mud removal pipe 22. After removing the mud and excavating a certain distance, the propulsion jack 24 is retracted, the formwork 25 is assembled, and the concrete 1 is placed in the space surrounded by the formwork 25, the ground 27, the press ring 3, and the existing concrete.
8 and press it with the press jack 2 during construction.

〔effect〕

According to the present invention, highly reliable water stoppage can be performed even in ground with high groundwater pressure, making it possible to construct an economical tunnel structure using the cast-in-place lining shield method that does not require expensive segments. . Furthermore, even when using the muddy water shield method, it is possible to prevent the muddy water pressure acting on the face from flowing into the tail and flowing into the tunnel. Therefore, the ground conditions to which the cast-in-place lining shield method can be applied can be expanded.

In addition, since the water-stop packing provided on the outer periphery of the press ring is expandable and retractable, it is also possible to line the tail plate with a waterproof sheet, and it is also possible to obtain a tunnel structure with higher water-stop properties.

[Brief explanation of the drawing]

Figure 1 is an overall sectional view of the construction state, Figures 2 and 3 are AA and B-B sectional views of Figure 1, Figure 4 is an enlarged sectional view of the main parts, and Figure 5 is a press FIG. 6 is a perspective view of a portion of the ring, and FIG. 6 is a perspective view of the tail plate of the shield machine.

Claims (1)

[Claims] (1) In the cast-in-place lining shield construction method, in which the tunnel wall excavated by a shield machine is lined with cast-in-place concrete, a stopper provided on the outer periphery of the press ring is used to expand and contract the inner periphery of the tail plate and to freely adjust the pressing force. It consists of a water packing and a water-stop packing provided on the inner periphery of the rear end of the tail plate, which is expandable and contractible against the outer circumferential surface of the existing concrete and whose pressing force can be freely adjusted. A water stop device for a shield machine, characterized in that water stop packing is used simultaneously or alternately to prevent water from entering the shield machine from outside.