JPS6124798A - Secondary covering construction method of shield construction - 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 The present invention is mainly used for shield work, etc. in which concrete is rolled up around the inner circumference of steel segments.
Regarding the construction method of next lining.

Conventionally, when performing secondary lining, segment 1 of the primary layer knee
When pouring concrete C, the vertical rib 2° of ′ becomes an obstacle, and when concrete C is cast, the concrete input side rises at the top (indicated by A), then moves to the gable side 6′ (indicated by mouth), and finally the gable side. 6゛ rises (indicated by C). However, if the construction method continues as it is, a gap A will be created between the vertical ribs 2° at the top of segment 1°, and as a result, ground B will sink due to corrosion of segment 1°.

There were problems such as pipe damage and water leakage. 8゛ is the horizontal rib.

The present invention has been made in view of the above points, and its purpose is to prevent the formation of voids in the segments without complicating the process. The present invention provides a construction method for secondary lining.

The present invention will be described below based on the illustrated embodiments. This will be explained in detail.

Reference numeral 1 denotes a steel segment, and ribs 2 and 8 are provided in a grid pattern on the inner periphery, and vertical ribs 2 and 8 are provided in the circumferential direction.
However, horizontal ribs 8 are formed in the axial direction. Reference numeral 3 denotes an air vent pipe, and the tip of the branch pipe 9 is opened between each vertical rib 2, and the other end of the air vent pipe 3 is led out from the end side 6 of the segment. 10 is an inner frame, and 11 is a concrete inlet. However, concrete input port 1
When concrete is poured from 1 to the concrete rolling part 4 of the segment 1, air that tends to accumulate between the shrinking ribs 2 at the top end of the segment 1 is successively discharged from the air vent pipe 3. In addition, in the illustrated embodiment, two air vent pipes 3a and 3b are arranged, a large diameter air vent pipe 3a and a small diameter air vent pipe 3b.
Branch pipe 9a of each air vent pipe 3a, 3b in the center part of the top
, 9b are overlapped to increase the displacement.

Therefore, when pouring concrete, even if a large amount of air tends to accumulate in the center as shown in FIG. 2 of the conventional example, the air can be smoothly discharged to the outside. Reference numeral 12 denotes a hanging tool made of wire.

Next, the relationship between filling concrete and discharging air will be described. First, as concrete is being filled, air is discharged from the large and small diameter air vent pipes 3a and 3b. When the filling is continued further, the exhaust from the small diameter air vent pipe 3b is stopped, and then the exhaust from the large diameter air vent pipe 3a is stopped to complete the filling. In addition, large diameter air vent pipe 3
For example, a has a diameter of 161mm, and the small diameter air vent pipe 3b has a diameter of 131mm, for example. Moreover, if the tip of the branch pipe 9 is V-shaped as shown in FIG. 5, the void can be reliably removed.

As described above, the present invention opens one end of the air vent pipe between the vertical ribs at the top end of the segment, and guides the other end of the air vent pipe to the concrete rolling part of the segment. Since concrete is placed in the rolled-up part, the vertical ribs at the top of the segment communicate with the outside wall through the air vent pipe. The air that tends to accumulate between the ribs can be gradually exhausted to the outside as concrete is poured, and as a result, the secondary lining has the effect of preventing voids from forming at the top and structural defects from occurring. Once the air vent pipe is installed, the air will flow out naturally through the concrete injection pass, so it has the advantage of being less complicated than conventional construction methods.

[Brief explanation of drawings]

Figure 1 is a longitudinal sectional view after construction using the conventional construction method, Figure 2 is a sectional view taken along line X-X in Figure 1, Figure 3 is a sectional view before concrete is poured using the method of the present invention, and Figure 4 is 3 is a sectional view taken along line YY in FIG. 3, FIG. 5 is a view showing another embodiment of the air vent pipe, and FIG. 6 is a perspective view of the entire segment. l-segment, 2-vertical rib, 3-air vent pipe, 4-concrete hoist.

Claims (1)

[Claims] (1) One end of the air vent pipe is opened between the vertical ribs at the top of the segment, and the other end of this air vent pipe is led out of the concrete rolling part between the segments, and then concrete rolling of the segment is performed. A construction method for secondary lining in shield construction, etc., which is characterized by pouring concrete into the area.