JPH0527755B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Application of the Invention The present invention relates to a tunnel docking method in a mechanized shield.

``Problems to be solved by conventional techniques and inventions'' Generally, when constructing a long tunnel using the shield method, excavation is performed from both sides and the tunnel is docked in the middle, but in sites where the ground is soft such as undersea tunnels. There was a problem of the ground collapsing in the Dotsuking section.

In order to solve this problem, conventional methods have been used, such as freezing the ground around the docking part in advance, improving the ground by injecting chemicals, and then excavating from both sides, or installing support hoods that can move forward and backward at the tips of both shield bodies. A known method is to do this, then stick out the mutual support hoods and join them after docking.

However, in the former method, it is inefficient because it is necessary to stop excavation and implement soil improvement methods before docking, and in particular, the freezing method requires a large amount of time and cost to form frozen soil, and the chemical injection method However, there were drawbacks such as the fact that reliable solidification could not be expected.

In addition, in the latter case, if the excavation position is misaligned or the excavation direction is oblique, the two supporting hoods may become misaligned or cannot be ejected, resulting in a drawback that safe and reliable docking cannot be expected.

"Means for Solving the Problems" In order to solve the above-mentioned conventional problems, the present invention has the following features:
A cylindrical slide shell that can be freely expanded and contracted in the radial direction is provided on the outer periphery of the shield body of one of the shield machines. By covering the outer periphery between the shield bodies, even if the mutual excavation positions are shifted or the excavation directions are oblique, the earth retaining reinforcement can be formed by covering the outer periphery between the shield bodies with sufficient margin. At the same time, hardening liquid is injected between the ends of the mutual shield machine and the excess excavation part to solidify it with the slide shell, and in this state, the solidified soil and equipment between the ends of the shield are removed to ensure safe docking. This paper proposes a construction method that allows for penetrating construction.

"Embodiment" Hereinafter, an embodiment of the present invention shown in the drawings will be described. A cylindrical slide shell 2 that can be expanded and contracted in the radial direction is attached to the outer periphery of one of the shield bodies 1 in two shield machines that dig in mutually opposite directions. Temporarily fasten.

The slide shell 2 is made by bending thin steel plates into a cylindrical shape and overlapping both ends so that they can slide into contact.
During excavation, the shield body 1 is fitted into a ring-shaped recess 3 on the outer periphery of the shield body 1, and both overlapping ends are temporarily fixed in a contracted state by fixing bolts 4 screwed from inside at the bottom of the shield body 1. It is held on a circumferential surface that is approximately the same as the outer circumferential surface.

A pull rope 5 such as wire is connected to the rear end of the slide shell 2 at a plurality of locations, and the end portion of the pull rope 5 is drawn into the inside of the shield body 1 through a through hole provided therein.

Attach slide shell 2 to one side like this,
While building a shield tunnel using a shield machine that does not have this on the other hand, we excavate sequentially from both sides,
When both of them reach the vicinity of the docking part, the over cutter 6' on the outer periphery of the rotary cutter 6 is extended to excavate the surrounding area until they approach each other.

When the shield machines come close to each other, the digging is stopped, and after removing the fixing bolt 4 of the slide shell 2 to make it free, an expansion means that presses the inner circumferential surface of the slide shell 2 outward is used to remove the screw from the outer periphery of the shield body 1. Expand radially outward to separate.

As shown in FIGS. 3 and 4, for example, this expansion means involves screwing in a large number of extrusion bolts 7 from the inside to the outside at approximately equal intervals along the circumferential direction of the shield body 1, and sliding them at their tips. A means of pressing and expanding the inner peripheral surface of the shell 2, or a means of pressurizing and expanding with a jack instead of the extrusion bolt 7 is used.

In addition, as another expansion means, slide shell 2
A strong magnet is attached to the inner surface of the slide shell 2, and a magnet with a repelling magnetic pole is brought close to the magnetic pole of this magnet from the shield body 1 side, and the expansion is caused by the repulsive force of the magnetic force, or an air bag is installed inside the slide shell 2. It is also possible to adopt a method of expanding the inflatable body by setting an inflatable body in a contracted state and filling the inflatable body with a fluid such as air or mortar from the inside of the shield body 1 to expand it. .

The slide shell 2 expanded in the extra digging part A in this way is slid toward the tip by pulling the pull cable 5 inside the shield body 1, and is fitted around the tip of the other opposing shield body 1'. , and covers the area between the tips of both shield bodies 1 and 1'.

At this time, even if the positions of both shield bodies 1 and 1' are slightly misaligned or diagonal, since the slide shell 2 has a larger diameter than the shield body 1 and has a margin, it will ensure that the other shield body 1 ′ can be fitted.

Next, pour muddy water solidification liquid from the injection port into the part B between the tips of the partition walls 8 and 8 of both shield bodies 1 and 1' and the extra digging part A from the partition wall 8 of the shield bodies 1 and 1' or around the rotary cutter 6. inject.

After the over-excavation part A and the part B between the tips are solidified, the partition wall 8 and the tip equipment such as the rotary cutter 6 are removed, and the solidified part B between the tips is further excavated and removed to dock both shield tunnels.

In this case, the solidified body formed by the solidified liquid solidifies together with the slide shell 2, maintains water-stopping properties, and strengthens the supporting force around the docking part, so that the collapse of the solidified body due to the pressure of the ground around the docking part is prevented. can be prevented and removal work can be carried out safely.

"Effects of the Invention" A shield machine consisting of a radially expandable and contractible slide shell made by rolling a thin steel plate into a cylindrical shape and overlapping both ends and temporarily fixing it in a contracted state to the outer periphery of the shield body is used to excavate from one side. Excavate from the other side with a regular shield machine, excavate with both rotary cutters near the docking parts of both, and when both shield machines approach, release the temporary fixing of the slide shell and remove from the inside of the shield body. The slide shell is expanded by protruding a plurality of push-in bolts radially outward, and in this state the slide shell is advanced to cover the outer periphery of the tip of the shield body of both shield machines, so that the mutual excavation position is adjusted. Even if the shield bodies are misaligned or the directions of excavation cross each other obliquely, the outer periphery between the shield bodies can be reliably covered with sufficient margin.

Further, a solidifying liquid is integrally injected into the part between the tips of both shield machines and the over-digging part, and solidified,
After that, the tip equipment of both shield machines and the solidified part between the tips are removed, so a slide shell integrated with the solidified body strengthens the supporting force around the docking part and ensures water-stopping properties to form an earth retaining, The part between the tips can be safely removed and docked, and the construction period and cost can be reduced.

[Brief explanation of drawings]

Fig. 1 is a vertical side view showing the shield machine according to the present invention in a state immediately after docking, Fig. 2 is a longitudinal front view showing the slide shell installed, and Fig. 3 is a longitudinal front view showing the slide shell in the expanded state. 4 are longitudinal sectional side views showing the sliding state of the slide shell. 1, 1'... Shield body, 2... Slide shell, 3... Recess, 4... Fixed bolt, 6... Rotating cutter, 6... Over cutter, 7... Extrusion bolt, 8... Partition wall, A... Extra digging department, B...
...The part between the tips.

Claims (1)

[Claims] 1 A shield machine is made by rolling a thin steel plate into a cylindrical shape, overlapping both ends, and temporarily fixing a slide shell that can expand and contract in the radial direction in a contracted state to the outer periphery of the shield body. Excavation is carried out using the shield machine, and additional excavation is carried out using both rotary cutters near the docking parts of both machines. When both shield machines are close to each other, the temporary fixation of the slide shell is released and the slide shell is expanded outward, and in this state, The slide shell is advanced to cover the outer periphery of the tips of the shield bodies of both shield machines, and the curing liquid is injected and solidified into the part between the tips of both shield machines and the extra digging part, and then both A tunnel docking construction method for a mechanized shield, characterized by removing the tip material of the shield machine and the solidified portion between the tips.