JPS5844839B2 - Shield method in construction method of shield type underground structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shielding method in a method of constructing a shielded underground structure.

Regarding the construction of underground structures such as tunnels for subways, water supply and sewage systems, and buried power cables, various construction methods such as open cut and caisson construction have been developed, but recently the use of shield construction methods has rapidly increased.

This shield method involves introducing a shield type tunnel excavation machine from a vertical hole, inserting the machine into the hole to be excavated,
A horizontal hole is excavated to pump water and discharge muddy water, and then a segment is inserted and mortar is pumped into the gap between the segment and the horizontal hole to construct a tunnel. It is unique in that it is done in a sealed manner.

Conventionally, this sealing work was performed in two stages.

That is, first, the machine is inserted into the opening, and then the worker cuts the ring put into appropriate sections and connects them one by one to the surrounding backing plate by welding, etc. to seal the machine in the opening, and then the machine is sealed in the opening. When drilling is finished, the outer diameter of the segment and the first
Workers had to connect another fan-shaped plate one by one to the ring plate by welding or the like between the stage ring plates.

However, performing the sealing work in two stages in this way did not speed up the work, required a large number of hands, and the work itself was dangerous because each fan-shaped plate of the ring plate was a heavy object. .

Furthermore, since the ring plate is added, the strength of the connecting portion is reduced, which poses a problem in protecting the backing.

This invention provides a method for constructing an underground structure by attaching a backing made of a soft material to the entrance of an opening for constructing an underground structure, excavating a hole while maintaining a sealed state with the backing, and then pressurizing mortar after inserting a segment. A movable slide ring plate is attached to the outside of the backing, and after inserting an excavator into the opening, the ring plate is moved until it reaches the outer periphery of the excavator, and a drilling hole is bored and the segment is moved into the excavation. The object of the present invention is to solve the above problem by moving the ring plate after inserting it into the hole until it reaches the outer periphery of the segment.

Next, the present invention will be explained based on the illustrated embodiment. First, the concrete blocking the entrance of the tunnel opening is broken to form the opening 1.

Next, a backing 2 made of a soft material such as rubber, a backing press plate 3, and a slide ring plate 4 are sequentially stacked and attached to the entrance of the opening 10 using anchor bolts 5.

At this time, the backing 2 is installed so that most of it is inside the opening 1, and the slide ring plate 4 is installed so that its tip is aligned with the inner diameter position of the opening 1 (
(See Figure 1).

The slide ring plate 4 has a fan-shaped plate 6 formed by appropriately dividing a link plate formed by two concentric circles on a line toward the center, and a fan-shaped plate 6 adjacent to the fan-shaped plate 6 around the opening 1. Attach with a slight gap 7 between them.

A long hole 8 for sliding is bored in each fan-shaped plate 6, and at this stage, that is, before the opening 1 of the excavator 9 is inserted, the slide ring plate 4 is located at the part of the long hole 8 that is closest to the opening 1. It is supported by the anchor bolt 5 (see Fig. 2).

Next, the excavator 9 is inserted into the opening 1.

The backing 2 is then pushed by the excavator 9 and most of it is inserted into the opening 1, where the opening 1 is sealed from the outside.

At this stage, by loosening the anchor bolts 5, the slide ring plate 4 is slid inside the opening 1, and its tip is moved to the outer peripheral position of the excavator 9 (see FIGS. 3 and 4).

Excavation then begins, and the excavation is carried out by supplying pressurized water and discharging muddy water by the excavator 9.

At this time, the backing 2 is subjected to strong pressure of muddy water.

The slide ring plate 4 protects the backing 2 against pressure.

When the excavation is completed in this manner, the segments 10 constituting water and sewer pipes, tunnels, etc. are inserted into the excavation hole.

At this stage, anchor bolts 5 are loosened, slide ring plate 4 is further slid inward of opening 1, and its tip is moved until it reaches the outer peripheral position of segment 10 (fifth
, see Figure 6).

When the mortar is pumped by the rear excavator 9, the backing 2 reaches the outer periphery of the segment 10 due to the force of the mortar, thereby preventing the mortar from leaking to the outside.

The slide ring plate 4 reinforces the pressure experienced by the backing 2.

An underground structure is constructed by sequentially repeating the above steps, but according to the present invention, the ring plate that protects the backing 2 does not need to be added for each step as in the past, and the anchor bolt 5 It can be slid to the desired position simply by tightening and loosening.

Therefore, according to the present invention, it is possible to speed up the shielding work, which has been extremely difficult in the past, and it is also possible to save labor and ensure safety of the work.

In this case, if the slide ring plate is moved by tightening and loosening bolts, the work will be faster, labor-saving, and safety will be further improved.

Further, according to the present invention, since the ring plate is single, the strength of the connecting portion is not a problem, and there is an effect that the backing can be completely protected.

[Brief explanation of drawings]

The drawings show an embodiment of the invention, and FIG.
A sectional view, FIG. 2 is a partial front view showing the state of the excavator before insertion into the opening, FIG. 3 is a BB sectional view of FIG. 4, and FIG. 4 is a partial front view showing the state of the excavator after insertion into the opening. FIG. 5 is a sectional view taken along the line CC in FIG. 6, and FIG. 6 is a partial front view showing a state in which mortar is pumped after segment insertion. 1... Opening, 2... Backing, 3... Backing press plate, 4... Slide ring plate, 5...
Anchor bolt, 6... Fan-shaped plate, 7... Gap, 8.
...long hole, 9...excavator, 10...segment.

Claims (1)

[Claims] 1. A backing made of a soft material is attached to the entrance of an opening for constructing an underground structure, a hole is excavated while maintaining a sealed state with the backing, and after inserting the segment, mortar is pumped to construct the underground structure. In the construction method, a movable slide ring plate is attached to the outside of the backing, and after inserting an excavator into the opening, the ring plate is moved until it reaches the outer periphery of the excavator, and a drilling hole is drilled and the segment is segmented. A shielding method in a method for constructing a shield type underground structure, characterized in that the ring plate is moved until it reaches the outer periphery of the segment after the ring plate is inserted into the excavation hole. 2. A shield method in the method for constructing a shield type underground structure according to claim 1, wherein the slide ring plate is moved by tightening and loosening bolts.