JPS60250194A - Shield tunnel partial enlarging construction method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a shield tunnel partial expansion method for partially expanding the cross section of a shield tunnel.

(Prior Art) Recently, there have been many cases in which ultra-high voltage electric cables are wired inside shield tunnels. In this case, since the connecting part of the tunnel cable requires a larger cross section than the other cable cross sections, conventionally all connections have been made within the shaft. However, in recent years, shield tunnels have tended to become deeper and deeper, and the method of installing vertical shafts requires a large amount of construction costs. The current situation is that construction is often extremely difficult due to the amount of road, road width, etc.

(Problem to be solved by the invention) Therefore, various construction methods have been proposed for partially enlarging the shield tunnel, but these construction methods require special machinery in sections where the construction length is extremely short. The construction method is complicated, the construction costs are high, and the construction period is long, so it is rarely used.

(Object of the Invention) The present invention has been devised in view of the above points, and is a shield tunnel that allows the cross section of the shield tunnel to be easily expanded by only working inside the shield tunnel, and that can be coated at low cost. The purpose is to provide a partial expansion method.

(Structure of the Invention) The present invention uses a segment having an opening/closing window and an earth anchor through hole in the upper segment of a partially enlarged section in a shield tunnel, and when constructing the expanded part, an earth anchor is driven through the through hole. At the same time, the opening/closing window is opened and the second part of the ground is scraped off, the segment is raised using the earth anchor as a guide, and an enlarged segment is attached to the subsequent side wall to partially enlarge the shield tunnel. It is possible to partially enlarge the cross section of the shield tunnel by simply working inside the shield tunnel without using special machines or equipment δ.

(Effects of the Invention) According to the present invention, the construction is extremely easy, and the upper segment can be reused as it is for the enlarged part, so it is economical and can be constructed at low cost.Moreover, the enlarged part has a vertical shape. Since it has an oval cross section, it has a large resistance to external forces. Further, since the segments of the enlarged section can be assembled in the same manner as other parts, it is possible to produce effects such as not adversely affecting the excavation speed during shield excavation.

(Example) Fig. 1 shows a segment of a partially enlarged section of Seal I tunnel, and Fig. 2 shows a side view of the segment. B segment) 3.
It consists of an A-segment main girder, and is assembled in the same manner as segments commonly used during shield excavation, using joints 5 between horizontal pieces, and joints 6 between rings.

In the second part, each of the B and A segments is composed of a skin play (7. Segment main girder 8. Segment joint plate 9, of which the B segment 3 and A segment 4 that make up the upper segment An opening/closing window 10, which will be described later, is provided, and the B segment 3 is also provided with a through hole 11 for an earth anchor, which will be described later.

Figure 3 shows the reinforcement 1 used to prevent deformation of the upper segment of the enlargement when it is raised.
2, and FIG. 4 shows its side view.
2 is a main girder 13 whose outer peripheral surface has the same radius of curvature as the inner surface of the upper segment. Connector 14 that connects the same nominative 13. Main girder 13
It is composed of an earth anchor through hole 15 and a washer 16 provided in the ground anchor.

Note that it is desirable to use steel as the reinforcing material, and in this example, a square pipe is used.

Figures 5 and 6 show enlarged segments;
Enlarged segment 17 shown in Figure (a) and left half of Figure 6
is skin plate 18. Consisting of segment f girder 19 and segment joint plate 20,
The enlarged segment j17a shown in the right half of the figure is a small-height segment that is used while piling up in a ground that is prone to collapse, and in this case, skin play 1-18. Segment main girder 19
．． It is composed of a segment joint plate 20 and a horizontal piece-to-piece joint 21.

FIG. 7 is a plan view of the segment having the opening/closing window 10, and FIG. 8 is a sectional view taken along the line A--A in FIG.

The segment main girder 8 is provided with an inter-ring joint bolt hole 22, and the segment joint plate 9 is provided with an inter-piece joint bolt hole 2.
3, a window 24 is provided approximately in the center of the skin play door and can be opened and closed via a bolt 25 and a nut 26.

Next, the procedure for partially enlarging the shield tunnel will be explained with reference to FIGS. 9 to 13.

Figure 9 (a) is an axial cross-sectional view of the shield tunnel before expansion construction, (b) is its A-A line, and (C) is B-B.
It shows a cross-sectional view taken along the line. 31 is the ground, 32 is the shield tunnel-crotch part, 33 is the shield tunnel expansion part, 34 is the "two-part segment of the expansion part, 35 is the lower segment of the expansion part," the two-part segment 34 and the lower segment 35 are , the segments already explained in FIGS. 1 and 2.

First, as shown in FIG. 10(a), and FIG. The earth anchor 38. into the nib knob in parallel for each upper segment, and inject the chemical into the chemical injection zone 37,
Furthermore, the reinforcement 12 is attached to the inside of the upper segment 34. Driving the earth anchor 38 and injecting the chemical liquid into the hole installed in the mine can be done through a grout hole installed in the segment, and the reinforcing material 12
For installation, the earth anchor 38 may be passed through the through hole 15 and fixed with a nut 38, as shown in FIGS. 14 and 15.

Next, the nut 26 is removed, the window 24 of the upper segment 34 is opened, and the upper segment 34 is raised together with the reinforcing material 12 by rotating the nut 38 while scraping off some of the ground 31.

FIG. 11(a) shows that some of the upper segments 34 are raised to a predetermined position as described above, and then the enlarged segment 1
7 is a cross-sectional view of the tunnel in the axial direction in a state where it is attached. Also, (b), , ('C) is A-A in (a)
3 shows a cross-sectional view taken along the line and the line B-B.

This work is not done in the enlarged section at the same time, but at appropriate intervals, for example, every other ring as in this example.
This will be carried out while ensuring safety.

Note that excavation can be done manually or by using a small breaker. In addition, in the case of a rock that is prone to collapse, for safety reasons, it is possible to carry out the process by stacking enlarged segments (17a) with a small height.

FIG. 12(a) shows the upper segment 34 of the entire enlarged section.
It is a sectional view in the tunnel axial direction showing a state in which the enlarged segment) 17 has been expanded in two parts to a predetermined position.
b) and (C) are cross-sectional views taken along line AA and line BB.

After raising the two-part segment 34 to a predetermined position in this way, the tunnel axial cross section 1Δ in FIG. As shown in Figure 3, the earth anchor 38 is cut near the inner peripheral surface of the upper segment 34 and the reinforcing material 12 is removed to complete the primary lining of the shield tunnel expansion section, and then concrete is poured and the secondary lining is completed. Construction of the enlarged section will be completed by carrying out this work.

According to the shield tunnel partial expansion construction method described above, the following numerous effects can be obtained.

(1) It is economical because the segments used during shield excavation can be reused as they are for the expansion part.

(2) Since the enlarged section has a vertical oval cross section, the resistance to external forces is increased, making construction of the enlarged section economical.

(3) During shield excavation, the segments of the enlarged portion can be assembled in the same way as normal segments, so the shield excavation speed is not affected in any way.

(4) Construction is extremely easy because some segments are raised using the earth anchor as a guide.

(5) Construction cost as no special machinery or equipment is required]
・It is inexpensive.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the segment, and FIG. 2 is a side view of FIG. 1. FIG. 3 is a sectional view of the reinforcing material. Fig. 4 is a side view of Fig. 3, Figs. 5(a) and 5(b) are cross-sectional views of the enlarged segments, and Fig. 6 is an enlarged view of the left half shown in Fig. 5(a). Segment, the right half is a side view of the enlarged segment shown in FIG. 5(b), FIG. 7 is a plan view of the segment having an opening/closing window, and FIG. 8 is a cross section taken along line A-A in FIG. 7. Figures 9 to 13 are explanatory diagrams of the construction procedure for the enlarged section, and each (a
) is an axial cross-sectional view of the shield tunnel, and (b) is its A
-A line and (C) are views showing cross sections taken along the line B-B; FIG. 14 is an enlarged view of section C in FIG. 11; and FIG. 15 is a plan view of FIG. 10. 1...Segment, 10...Opening/closing window. 11... Earth anchor through hole, 12... Reinforcement material. 15...Earth anchor through hole. 17.17a... Expanded segment, 31... Rock. 32...Shield tunnel general 6B. 33... Shield tunnel expansion part. 34..." two-part segment, 37... chemical liquid injection zone. 38...Earth Anchor, 38...Natsuto. Applicant: Kumagai Gumi Co., Ltd. Attorney: ±9 Funabashi Kuninori Figure 13 (a) Figure 14 (b) (c) Figure 15

Claims (1)

[Claims] A segment having an opening/closing window and an earth anchor through hole is used in the upper segment of the partially enlarged section in the shield tunnel, and when the enlarged part is installed, the earth anchor is driven through the through hole and Open the operable window and scrape off the top 8 tons of ground, use the earth anchor as a guide to JJI the upper segment 1, and then attach an enlarged segment to the side wall to partially enlarge the shield tunnel. A shield tunnel partial expansion method that is characterized by: 2. The method for enlarging a portion of a shield tunnel according to claim 1, wherein a reinforcing member is attached to the inside of the upper segment via a nut. 3. The shield tunnel partial expansion construction method according to claim 1, characterized in that as the two-part segment rises, a plurality of small-height expansion segments are stacked and attached. 4. Shield tunnel partial expansion construction method 6 as set forth in claim 1, characterized in that construction of the expansion section is carried out at appropriate intervals within the expansion section.