JPH0480198B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] After assembling the segment ring for the primary lining within the shield tail, the inner formwork ring having radially slidable members at both ends is assembled, and the second This invention relates to a method for integrally constructing a shield tunnel that takes advantage of the primary lining, which enables simultaneous construction of primary and secondary linings by placing secondary lining materials.

[Conventional technology]

Conventionally, a tunnel with only a primary lining was penetrated, and then a secondary lining was constructed, which increased the construction period.
Because the period in which the primary lining alone supports the earth load is relatively long, and the change in load during that period is not clear, the primary lining has no choice but to be designed as a permanent structure, and the secondary lining has a strong However, this method had drawbacks such as the fact that the above was not taken into account, making the lining extremely uneconomical.

[Problem that the invention seeks to solve]

This invention attempts to solve the problem of prolonging the construction period by applying a secondary lining after the completion of the primary lining, and the uneconomical problem of making the primary lining a permanent structure.

[Means for solving problems]

Assemble and fix the primary lining segment in front of the existing primary lining segment, fill the outside of the primary lining segment with backfill material, and fill the front part of the existing inner formwork with the inner formwork. Assemble the formwork in a staggered manner, slide the rear gable of the inner formwork that is connected to the front gable of the existing inner formwork outward, and then contract the next gable ring inward. Lining material is injected into the lining material injection space surrounded by the expanded gable frame, primary lining segment, existing secondary lining, and inner formwork, and at the same time, the shield machine is used to excavate one step to complete the excavation. This problem was solved by retracting the rear shield jack to form a space in the tail for assembling segments, etc., and repeatedly assembling the primary lining segment in front of the existing primary lining segment.

[Effect]

Assemble and fix the front primary lining segment of the existing primary lining segment, assemble the inner formwork in a staggered manner to the front of the existing inner formwork, and
After sliding the rear gable of the inner formwork connected to the front gable of the existing inner formwork outward, the next gable ring after the gable is shrunk inward, and the diameter of the gable frame expanded,
The lining material is injected into the lining material injection space surrounded by the primary lining segment, the existing secondary lining, and the inner formwork, and at the same time, the shield machine is excavated for one step, and the primary lining segment is removed during or after excavation. Fill the tail void on the back of the tunnel with backfill material, and after the excavation is completed, shrink the shield jack to form a space in which to assemble segments, etc. in the tail, and assemble the primary lining segment in front of the existing primary lining segment. By repeating this process, it is possible to construct the primary lining and secondary lining at the same time, which shortens the construction period.
From the initial stage of application of the ground load, both linings function as a composite section, making it possible to achieve an extremely economical section.

〔Example〕

The primary lining segment 2 is assembled and fixed to the front part of the existing primary lining segment 1 to form a segment ring. Thereafter, the inner formwork 5, which has main reinforcing bars and distribution bars inside the primary lining segment 2, and a slidable end frame 4 before and after the reinforcement is assembled and fixed to the front part of the existing inner formwork 6. However, the existing inner formwork 6
The inner formwork 5 provided in series with the inner formwork 5 is assembled in a staggered manner (see Fig. 8).

The inner forms 5 and 6 have the same structure and are divided into four parts in the circumferential direction of the tunnel, and bolt holes 8 are bored in the joint plates 7 on both sides to connect with the adjacent inner forms 5.

The end frame 4, which is formed in the same arc shape as the inner formwork on the outside, is slidably attached to the front and rear surfaces of the inner formworks 5 and 6, and is placed in a place inside the inner formwork where it will not interfere with the work. Slide it using the provided jack 9. Drill long holes 11 in the front and rear plates 10 of the inner formworks 5 and 6, insert the operating rods 12 into the front and rear elongated holes 11, fix the end plates 4 to the front and rear ends of the operating rods 12, and attach the rods of the jacks 9 to the operating rods. 12, the end plate 4 is slid by the operation of a pivoting jack 9. Jacket 9 is inner formwork 5,
It can be attached to a reinforcing member etc. provided on the inside of 6, and can be used for other purposes.

To describe the construction of the lining material injection space 25 in detail, the inner formwork 5 is connected to the front part of the existing inner formwork 6, and is fixed using bolts and nuts through the bolt holes 17, and the entire circumferential direction is assembled. Once finished, replace the existing inner formwork 6
The front gable 4 and the rear gable 4 of the connected inner form 5 are operated by the jack 9 to extend the rod and slide the gable 4 outward to form a gable ring. The frame ring is shortened and the front parts of the existing inner formwork 6 and the existing primary lining segment 1 are closed airtight, and the existing inner formwork 6, the existing lining 23, the existing primary lining segment 1 and the gable are closed. The frame 4 forms a lining material injection space 25.

Thereafter, the lining material is injected into the lining material injection space 25 from the lining material injection pipe 22, and at the same time the shield jack 20 is operated to remove the reaction force from the primary lining segment 2 and cause the shield machine 18 to dig for one step. .
During excavation or after completion of excavation, primary lining segment 2
A backfilling material is injected into the tail void 3 formed between the ground and the ground.

Thereafter, the shield jack 20 is operated to retract the rod by one step and connect the primary lining segment 2 to the front part of the existing primary lining segment 1.

Therefore, the name of the primary lining segment 2 described in the previous section is changed to the existing primary lining segment 1, and this operation is repeated one after another to construct a shield tunnel.

When sealing the primary lining segment and the front part of the inner formwork with the end frame 4, fit the distribution bar into the groove 16 of the end frame 4,
Seal the gaps with sealing material to prevent the flow of lining material.

In addition, after connecting and assembling the primary lining segments, main reinforcing bars and distribution bars may be arranged, but when producing the primary lining segments at a factory,
It is also possible to simply arrange the reinforcement as shown in the figure and assemble it on site.

The primary lining segment 1 has a reinforcing bar hanging jig 1 on the inner surface.
3, and arrange the main reinforcing bars 14 and distribution bars 15,
A groove 16 for inserting the distribution bar 15 is cut into the end frame 4 from the outer end.

17 is a bolt hole for connecting the inner formworks 5 and 6; 18
A plurality of plates 19 are fixed on the same circumference inside by a shield machine, and a cylinder of a shield jack 20 is fixed to the rear of the plate 19, so that the rod can come into contact with the primary lining segment 1.

21 is a selector, 22 is a lining material injection pipe, 23
24 is the existing lining material, 24 is the skin plate of the inner formwork,
25 indicates a lining material injection space.

〔Effect of the invention〕

Because it is possible to construct the primary and secondary lining at the same time,
It is possible to shorten the construction period.

Furthermore, since both linings function as a composite cross section from the time when the initial ground load is applied, it is possible to realize a cross section that is extremely economical compared to conventional construction methods.

[Brief explanation of drawings]

Figure 1 is a vertical cross-sectional view of the tunnel, Figure 2 is a front view of the primary lining segment, and Figure 3 is a--
Fig. 4 is a view from the a-a arrow in Fig. 1, Fig. 5
The figure is a rear view of Fig. 4, Fig. 6 is a view taken along the b-b arrow of Fig. 5, Fig. 7 is a view taken along the c-c arrow of the same, and Fig. 8 is a plan view showing how to assemble the inner frame ring. be.

Claims (1)

[Claims] 1. Assemble and fix the primary lining segment in front of the existing primary lining segment, assemble the inner formwork in a staggered manner in front of the existing inner formwork, and attach the inner formwork to the front of the existing inner formwork. After sliding the rear gable of the inner formwork connected to the front gable of the inner formwork outward, the next gable ring is contracted inward, and the expanded gable, primary lining segment, and existing Inject the lining material into the lining material injection space surrounded by the secondary lining and inner formwork,
At the same time, the shield machine is excavated for one step, and after the excavation is completed, the shield jack is retracted to form a space in the tail for assembling segments, etc., and the work of assembling the primary lining segment in front of the existing primary lining segment is repeated in sequence. An integrated construction method for shield tunnels that takes advantage of the primary lining.