JP2860665B2 - Construction method of flexible joint - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for constructing a flexible joint such as a shield segment or a box culvert used for a culvert.

2. Description of the Related Art In a culvert such as an underground drainage channel, it is common practice to connect each single unit of a tubular structure to each other by using an expandable and contractible flexible joint. The flexible joint is formed of an elastic member such as a thick soft rubber cylinder or a thick rubber cylinder containing reinforcing fibers.

A conventional process for constructing this flexible joint will be described with reference to FIG.

First, at the time of primary construction, as shown in FIG. 1 (a), a thrust receiving member 3 and a hanging plate 4 are attached to a frame segment 2 in a shell 1 of a shield machine, Assembled by the erector 6. Reference numeral 7 denotes a tail packing that keeps the inside of the shell 1 airtight.

When the assembly of the frame segment 2 is completed, a part of the thrust receiving member 3 is removed, and both ends of the primary water stopping elastic body 8 are fastened to the frame segment 2 with bolts 9 as shown in FIG. Then, the primary water stopping elastic body 8 is fixed.

At the place where the fixing of the primary water stopping elastic body 8 is completed, the thrust receiving member 3 is attached again. This operation is sequentially performed in the circumferential direction of the cylindrical body, and the primary water stopping elastic body 8 and the thrust receiving member 3 are arranged all around the cylindrical body.

In this state, a thrust can be received. Therefore, as shown in FIG. 1 (c), a thrust by the jack 10 of the shield machine is applied to perform a normal propulsion operation.

Next, at the secondary construction stage where the influence of the thrust has disappeared, all the thrust receiving members 3 are removed as shown in FIG. 1 (d).

Then, as shown in FIG.
The elastic member 11 for secondary water stop is attached to the inside, the holding plate 12 is fitted, and the elastic member 11 for secondary water stop is fixed to the frame segment 2 by the mounting bracket 13. This work is performed over the entire circumference of the cylindrical body, and the secondary construction is completed.

Thereafter, as shown in FIG. 1 (f), when the secondary lining concrete 14 is cast, the joint material 15 is filled between the holding plates 12.

In this way, a segment with a flexible joint is constructed.

Problems to be Solved by the Invention In the conventional construction method, attachment and detachment of the thrust receiving member 3 are frequently performed as described above. Therefore, the number of work steps was extremely large, and the work was inefficient.

Also, depending on how the thrust receiving member 3 is attached,
The reaction force transmitted via 10 tends to vary. For this reason, the frame segment 2 and the thrust receiving member 3 are deformed, and it becomes difficult to remove the thrust receiving member 3 at the time of the second execution.

In addition, groundwater may penetrate the elastic body 8 for primary water stoppage and leak water, so that both the first construction and the second construction are extremely difficult.

Means for Solving the Problems and Effects The present invention relates to an improvement in a method of constructing a flexible joint that overcomes such difficulties, and provides a plurality of longitudinal ribs in a circumferential direction between a pair of ring-shaped main girders. At the same time, a segment ring with a skin plate wrapped around the main girder is installed between the general segments, and the vertical ribs bear the thrust of the jack of the shield machine on the vertical ribs. After that, by cutting and removing a part of the vertical ribs and the skin plate constituting the segment ring, the segment ring is divided into two along the central axis direction of the segment ring, and the divided portion is flexible. It is characterized by providing a joint.

Since the present invention is configured as described above, when performing primary construction, it is possible to bear the thrust at the time of moating with the vertical ring of the segment ring, and with the skin plate of the segment ring. So,
Water leakage through the mortar layer on the outer periphery of the segment ring can be prevented.

Further, in the present invention, the segment ring is divided into two by cutting and removing a part of the vertical rib and the skin plate after the primary construction, so that the segment ring can have flexibility.

Further, in the present invention, since the flexible joint is provided in the two-part part, watertightness can be provided without impairing flexibility.

As described above, according to the present invention, when performing the flexible joint, it is possible to efficiently and easily perform the propulsion method without the need to install and remove complicated thrust receiving members, and furthermore, the vertical ribs By cutting and removing a part of the skin plate, the segment ring is divided into two parts, and a flexible member is attached to the divided part.
The flexible joint can be easily provided within a short time by a simple operation process.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 2 to 6. FIG.

At the time of primary construction, between general segments 21 such as steel
The skin plate 22 and the main girder 23 are arranged. This main girder 23
Has an annular shape following the shape of the general segment 21, and is reinforced by a plurality of longitudinal ribs 24 arranged in the circumferential direction.

The skin plate 22, the main girder 23 and the vertical rib 24 form a segment ring. Since the vertical ribs 24 extend in the tube axis direction, the segment ring can sufficiently receive the thrust during moating. Further, since the skin plate 22 is provided on the outer periphery, water leakage through the mortar layer 25 is also prevented.

That is, in the primary construction, the action exhibited by the thrust receiving member 3 and the primary water stopping elastic body 8 described with reference to FIG. 1 can be provided by assembling the segment ring.

Then, after performing a predetermined moating operation, as shown in FIG. 3, a part of the skin plate 22 and the vertical rib 24 constituting the segment ring is cut and removed. Thereby, the segment ring becomes flexible.

Then, as shown in FIG.
The receiving plate 26 is fixed by means of welding, the both ends of the flexible member 28 are sandwiched between the receiving plate 26 and the holding plate 27, and the whole is bolted.
Tighten with 29.

In this way, a flexible joint is provided between the general segments 21 in a simple procedure. In addition, since the flexible member 28 is attached after cutting the vertical rib 24, the gap between the general segments 21 on both sides, that is, the length of the flexible joint does not change in the circumferential direction, and the flexibility as in the initial design is achieved. Ability can be exhibited.

The cutting shape of the vertical rib 24 is not particularly limited, and may be a straight cut shown in FIG. 4 or a tapered shape shown in FIG. 5 or an arcuate curved surface shown in FIG. The ribs 24 can also be cut.

[Brief description of the drawings]

FIG. 1 shows a conventional method of installing a flexible joint in the order of steps, FIG. 2 shows a state in which a segment ring is assembled in one embodiment of the present invention, and FIG. FIG. 4 shows a state in which a flexible joint is attached to a cutting portion, and FIGS. 5 and 6 show another embodiment. 1. Shell of shield machine 2. Frame segment 3.
... Thrust receiving material, 4 ... Hang plate, 5 ... General segment, 6
…… Electer of the shield machine, 7 …… Tail packing,
8 ... Elastic body for primary waterproofing, 9 ... Bolt, 10 ... Jack of shield machine, 11 ... Elastic body for secondary waterproofing, 12 ... Presser plate, 13 ... Mounting bracket, 14 ... Next lining concrete,
15 joint material, 21 general segment, 22 skin plate, 23 main girder, 24 vertical rib, 25 mortar layer, 26 receiving plate, 27 holding plate, 28 ... Flexible members, 29
……bolt.

Claims (1)

(57) [Claims] 1. A segment ring in which a plurality of vertical ribs are arranged at intervals in a circumferential direction between a pair of ring-shaped main girders, and a skin plate is wound around an outer periphery of the main girders. Assembling between the general segments, after performing the primary construction by applying the thrust by the jack of the shield machine to the vertical rib, by cutting and removing a part of the vertical rib and the skin plate constituting the segment ring, A method for constructing a flexible joint, comprising: dividing the segment ring into two along the central axis direction of the segment ring; and providing a flexible joint at the divided portion.