JPH0460193B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] By partially using segment lining within the ring cross section to receive the propulsive reaction force of the shield machine, the good workability of the segment lining method can be utilized. However, this invention relates to a partial segment lining construction method for a shield tunnel, which makes it possible to reduce construction costs by partially adopting on-site casting.

[Conventional technology]

In general, the segment lining method has the problem of high segment unit costs, whereas in the case of the cast-in-place method, if the secondary lining is omitted, the total cost may be lower than the segment lining method. Although the cost is high, there are still many technical issues and it will take many years before this method becomes established.

[Problem that the invention seeks to solve]

There are problems such as the high cost of constructing the entire tunnel using the segment lining method, and the fact that with the on-site lining method, the reinforcement, assembly and disassembly of the framework or shoring, etc. are technically complex and require a large amount of labor. It is an invention that attempts to solve a problem.

[Means for solving problems]

Concrete segments are placed at regular intervals within the shield machine tail, and a steel rod is inserted into the seal in the longitudinal direction of the ring of the concrete segment to be continuous with the steel rod of the existing concrete segment, and the tip of the steel rod is fixed with a stopper. Then, reinforcement is placed between the concrete segments, and the formwork inside the steel segment is framed inside the reinforcement part using the H steel support member previously installed inside the concrete segment as a guide to form the H steel support member. They are joined together to form a supporting structure, a press ring is set in contact with the ring joint surface of the concrete segment, a cast-in-place slide form is airtightly inserted into the tip of the cast-in-place part between the concrete segments, and the press ring, Cast-in-place sliding formwork,
While injecting the lining material into the lining material injection space formed by the inner frame mold, concrete segment, existing lining, and shield machine tail, the reaction force is applied to the concrete segment via the press ring and the shield machine is activated by the shield jack. After excavating for a certain length, the reaction force is applied to the press jack receiver provided on the press ring at the front end of the adjacent concrete segment, and the press jack presses the cast-in-place slide formwork. After pressurizing for a certain period of time, the press ring is moved forward. The problem was solved by repeating the process of moving the concrete segment to the front end of the concrete segment and placing the concrete segment at the front end of the concrete segment.

[Effect]

Place concrete segments at regular intervals within the shield machine tail, insert a steel rod into the seal in the longitudinal direction of the ring of the concrete segment, connect it to the steel rod of the existing concrete segment, and secure the tip of the steel rod with a stopper. The H-steel support member is fixed and reinforced between the concrete segments, and the formwork inside the steel segment is framed inside the reinforcement part using the H-steel support member previously installed inside the concrete segment as a guide. A press ring is set in contact with the ring joint surface of the concrete segment, a cast-in-place slide form is airtightly inserted into the tip of the cast-in-place part between the concrete segments, and the press ring While injecting the lining material into the lining material injection space formed by the cast-in-place sliding formwork, inner formwork, concrete segment, existing lining, and shield machine tail, a reaction force is applied to the concrete segment via the press ring. The shield machine is made to dig a certain length with a shield jack, and the reaction force is applied to the press jack receiver provided on the press ring at the front end of the adjacent concrete segment, and the press jack is used to press the cast-in-place slide formwork to a certain extent. After applying pressure for a period of time, the press ring is moved forward and the concrete segment is placed at the front end of the concrete segment, which is repeated in sequence to create a segment lining in the cross section of the ring to receive the propulsion reaction force. By using the segment lining method, we aim to reduce costs by partially adopting cast-in-place construction while taking advantage of the ease of construction of the segment lining method. However, only one type is required instead of several types as in the past, which leads to a reduction in formwork manufacturing costs, and also eliminates the need for joint fittings, which account for a large portion of segment manufacturing costs.

Moreover, since the manufacturing accuracy of the concrete segment itself does not affect the accuracy of the lining, relatively rough manufacturing can be performed, which is advantageous.

In the cast-in-place method, the propulsion reaction force is transferred to the supporting member that also serves as the inner formwork, which puts pressure on the supporting member that also serves as the inner formwork, but in this method, the propulsion reaction force is partially distributed in concrete. Since it is supported by segments, it can be a relatively simple formwork support, and specifically, the cast-in-place part uses a steel segment-type inner formwork, and the H steel support member and inner formwork provided on the concrete segment are used. Basically, it closes in a ring shape.

Sleepers for track rail installation can be placed in parts of this concrete segment other than the H-steel support members, and the rear bogie can be towed to the front of the shield excavation section, allowing concrete placement work and soil distribution. This is advantageous in terms of work, and the main reinforcement can be efficiently placed using the anchoring overhang reinforcing bars and anchoring holes provided in advance in the concrete segment as guides, and the high strength of the concrete segment can be utilized to make this part the anchoring part. , it is possible to form a prestressed concrete structure at an early stage, and it has become possible to apply it to pressure tunnels.

〔Example〕

Concrete segments 2 are arranged at regular intervals in the shield machine tail 1, that is, at four locations divided into eight parts in the figure, and sheaths for fastening in the tunnel axial direction are provided by penetrating the concrete segments 2 at several locations in the longitudinal direction of the ring. Steel rod 4 inside 3
is inserted and connected to the stopper 6 screwed onto the steel rod 5 of the existing concrete segment, the tip of the steel rod 4 is fixed by the stopper 7, and the main reinforcing bars 8 and distribution bars 9 are inserted between the concrete segment 2. At the same time, using the curved H-steel support member 10 installed inside the concrete segment 2 in advance as a guide, formwork 11 inside the steel segment is framed inside the reinforcement part and connected to the H-steel support member 10. The cast-in-place slide formwork 14 attached to the tip of the rod of the press jack 13 provided on the press jack receiver 12 provided on the press ring 31 straddles the adjacent concrete segment 2 is then attached to the adjacent concrete segment 2 to form a support structure. Insert airtightly into the tip between 2 and place cast-in-place slide formwork 1.
4. The shield machine tail 1 is injected into the lining material injection space 16 formed by the inner formwork 11, the concrete segment 2, the existing lining 15, the press ring 31, and the shield machine tail 1 through the cocrete injection pipe 19. The shield jack 18 attached to the plate 17 provided inside was operated to apply a reaction force to the concrete segment 2 through the press ring 31, and the shield machine was made to dig a certain length using the shield jack 18, which was installed in the press ring 31. The reaction force is taken by the press jack receiver 12 and the press jack 13 pressurizes the cast-in-place slide form 14. After pressurizing for a certain period of time, the press ring 31 is moved forward and the concrete segment 2 is placed at the front end of the concrete segment 2. Construction is carried out by repeating the steps in sequence.

Horizontally install sleepers 21 for installing the track rails 20 across the concrete segments 2 on both sides of the lower part, and fix the two track rails 20 to the sleepers 21 in the axial direction of the tunnel. The trolley 23 is towed,
Can perform concrete placement work and earth removal work.

24 is an earth removal device, 25 is an erector, 26 is a reinforcing bar for fixing the main reinforcing bar 8 provided in the concrete segment 2, 27 is a fixing hole for the main reinforcing bar 8, and 28 is a segment ring in the tunnel axis direction provided in the press ring 31. This is a protrusion hole of the longitudinal fastening steel rod 4.

29 is a bolt nut for fastening the inner frame mold 11 and the H steel supporting mold member 10, and 30 is a bolt nut for connecting the segment 2 and H
This figure shows bolts and nuts for fastening to the steel supporting type member 10.

〔Effect of the invention〕

By partially using segment lining within the ring cross section to receive the propulsion reaction force, we can take advantage of the ease of construction of the segment lining method, while reducing costs by partially adopting on-site casting. can be achieved.

[Brief explanation of the drawing]

1 and 2 are sectional views of the tunnel, FIG. 3 is a sectional view taken along line A-A in FIG. 1, FIG. 4 is a sectional view taken along line B-B, and FIG. 5 is a sectional view taken along line C-C. FIG. 6 is a plan view of the lining material injection space, FIG. 7 is a perspective view of the segments, and FIG. 8 is a sectional view showing the connected state of the segments.

Claims (1)

[Claims] 1 Place concrete segments at regular intervals in the shield machine tail, insert a steel rod into the seal in the longitudinal direction of the ring of the concrete segment, connect it to the steel rod of the existing concrete segment, and secure the tip of the steel rod with a stopper. The H-steel support member is fixed and reinforced between the concrete segments, and the formwork inside the steel segment is framed inside the reinforcement part using the H-steel support member previously installed inside the concrete segment as a guide. A press ring is set in contact with the ring joint surface of the concrete segment, a cast-in-place slide form is airtightly inserted into the tip of the cast-in-place part between the concrete segments, and the press ring While injecting the lining material into the lining material injection space formed by the cast-in-place sliding formwork, inner formwork, concrete segment, existing lining, and shield machine tail, a reaction force is applied to the concrete segment via the press ring. The shield machine is made to dig a certain length using a shield jack, and the reaction force is applied to the press jack receiver provided on the press ring at the front end of the adjacent concrete segment, and the press jack pressurizes the cast-in-place slide formwork for a certain period of time. A partial segment lining construction method for a shield tunnel, which is characterized in that after pressing, a press ring is moved forward and a concrete segment is placed at the front end of the concrete segment.