JPH02171493A - Assembling means for segment in shield method - Google Patents

Abstract

PURPOSE:To facilitate the execution of works by setting up cement being inset finally at the more outward than an original set position in advance at a time when segments are annularly assembled in a shield excavator, and fitting it from the outside in the end. CONSTITUTION:Segments S are annularly assembled in order in a skin plate 2 of a tail part of an excavator while excavating natural ground with a shield excavator. Then, a segment S0, being finally set, situated at the inside of an overhang part 2a is fitted from the outside and annular assembly is thus completed. With this constitution, execution of works can be facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a method for assembling segments used as tunnel lining materials in shield construction methods.

"Prior Art" Generally, as an example of a tunnel construction method, for example, a shield construction method is known. This construction method protects the underground working space from dirt by pushing a shield excavator, which is entirely covered with a cylindrical skin plate, into the tunnel formed by the excavation as the excavation progresses. ,
The tunnel is constructed continuously by assembling arc-shaped segments into a ring within the shield excavator and connecting them in the axial direction, and by taking the reaction force from the annularly assembled segments and sequentially sending the shield excavator forward. This is Surushino.

By the way, when assembling the above segments into a ring, the last segment S. (so-called key segment)
The problem is how to fit it in. Conventionally, for example, the method of fitting it from the inside as shown in Fig. 3, or the method of fitting it by shifting it in the axial direction as shown in Fig. 4 is a problem. was taken.

"Problem to be Solved by the Invention" However, in the above-described conventional segment assembly method, the key segment S. , and the segments on both sides thereof must each have a unique shape different from the other segments (in the one shown in Figure 3, a key segment with tapers on both sides and a reverse taper T must be used, In addition, in the case shown in Fig. 4, key segments that are wedge-shaped in plan view must be used.) In the end, 3
There is a drawback that different types of segments must be prepared.

In addition, the segments are subjected to earth pressure and water pressure from the ground, but at this time, the key segment S shown in FIG.

is subjected to force in the direction of separating from the segments on both sides due to earth pressure, etc., and as a result, it becomes difficult to ensure water quality at the joints on both sides.

Further, in both the methods shown in FIGS. 3 and 4, when the key segment S0 is fixed to the segments S on both sides, the key segment S is fixed until the fixation is completed.

It has to be supported while keeping it in the correct position, which has the disadvantage of poor workability.

The present invention has been made in view of the above circumstances, so common trick 1
It is an object of the present invention to provide a method for assembling segments in a shield construction method that allows construction with different types of segments and has excellent water-stopping properties and workability.

"Means for Solving the Problems" In order to achieve the above object, the present invention aims to assemble a plurality of segments in a ring shape in the shield excavator and connect them in the axial direction while digging underground. In the shield construction method for constructing a structure, when assembling segments into a ring in the shield excavator, the last segment to be fitted is placed outward from the original set position, and the other segments are assembled in a circle. The feature is that after setting in an arc shape, the last segment to be set is fitted from the outside to assemble into a ring shape.

1. When forming an annular shape, the last segment to be set is not moved inward or in the axial direction, but is pushed in from the outside, so the last segment is the same as the other segments. Shapes are available.

Furthermore, when the segments are subjected to earth pressure and water pressure, the suppressing components such as the earth pressure act in a direction that brings the ends of each segment into tight contact with each other, so that good water-stopping properties can be ensured.

Furthermore, when the segment to be set last is fitted into the existing segments connected on the circular arc, it is positioned and supported by the segments on both sides, and the segment to be set last is fitted with bolts, etc. There is no need to provide special support to the segment on either side while the segment is being secured to the segment on both sides.

"Embodiment" An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram showing the process of assembling segments by the method of the present invention, and FIG. 2 is a longitudinal sectional view thereof.

Before explaining the method of the present invention, a shield excavator used to carry out the method will be briefly explained.

In Fig. 2, a shield excavator 1 is shown with reference numeral 1, and as is well known, the shield excavator 1 is entirely covered with a cylindrical steel skin plate 2, and excavates with a cutter 3 provided on the front. It consists of three parts: a hood part 4, a tail part 5 which performs lining at the rear, and a ring gutter part 6 which supports and reinforces the entire structure of the 7-ird excavator at the center thereof.

A hydraulic jack 7 for shield propulsion is provided in the ring garter portion 6 at the center, and an erector 8 is provided in the tail portion 5. The erector 8 has the function of assembling the segment S, and includes a grip device for gripping the segment S,
It is also equipped with an adjustment device that makes adjustments in three axial directions (elevating, sliding, and turning) to ensure smooth assembly.

Although the two skin plates have a cylindrical shape, a part thereof is formed with a projecting portion 2a that projects outward (in FIG. 2, the reference numeral L1 indicates the skin plate used so far). Indicates the line at one end, L
2 shows the line of the upper end of the skin plate used for carrying out the present invention).

The overhanging portion 2a may be provided anywhere in the circumferential direction, but in consideration of workability, it is preferable to provide it at the upper end as shown in FIGS. 1 and 2.

However, the length 121 needs to be set larger than at least the segment length g. In reality, when connecting the segments in the axial direction, the segments are arranged so as to be shifted in the circumferential direction so that the joints Z in the circumferential direction are not continuous as shown in FIG. Set it a little wider considering this. Further, the axial direction of the overhanging portion 2a is the same as that of the skin plate 2 as shown in FIG.
It may be provided so that it reaches from the front end to the rear end of the erector 8, or it may be provided so that only a portion corresponding to the erector 8 extends.

It should be noted that the shield excavator 1 is equipped with special excavation means so that it can also excavate the ground portion corresponding to the overhanging portion 2a.

Next, the method of the present invention will be clarified by explaining the operation of the shield excavator I.

In the shield excavator 1, while rotating the cutter 3 of the hood section 4, the hydraulic jack 7 is driven to remove the existing segment S.
The reaction force is taken from the excavator, and the excavator itself is sent out by gravity to excavate the ground.

While excavating in this manner, the rear tail portion 5 sequentially grips the segments S with the erector 8 and assembles the segments S into an annular shape. At this time, the segment S0 to be fitted last in assembling the annular shape was positioned inside the overhanging portion 2a, thereby placing it outward from the original center position, and the other segments S were set in an arc shape. After that, the last segment S. Set.

In this way, segment S is inserted last. Since the last segment S0 is set by being pushed in from the outside rather than from the inside or the axial direction, the last segment S0 can have the same shape as the other segments S. As a result,
In principle, only one type of segment is required, and segment management is much easier than when using conventional methods.

In addition, the segments S set in an annular shape are capable of absorbing earth pressure and
When receiving water pressure, the annular diameter receives a force that reduces its annular diameter, and as a result, as shown in FIG. F will act on it, and good water quality can be ensured.

Furthermore, segment S is set last. When fitting from the outside into the existing segments S connected on an arc, the segment S itself is positioned and supported by the segments S on both sides. While fixing the segment S to the segments on both sides with bolts etc. There is no need to support it, and workability is improved.

"Effects of the Invention" As explained above, according to the present invention, in principle, construction can be performed using one type of common segment, and segment management becomes easy. Moreover, when earth pressure and water pressure from the ground acts, the ends of each segment are pressed tightly against each other, resulting in good water-stopping properties. When fixing to a segment, there is no need to support the segment, which has the effect of improving workability.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a segment being assembled by the method of the present invention, FIG. 2 is a longitudinal cross-sectional view of the same, and FIGS. 3 and 4 are diagrams for explaining a conventional method of assembling segments. l...Shield excavator, 2...Skin plate, 2a...Protrusion part, 5...Tail part, 8...Erector, S... ...Segment, So...Segment to be set last. Applicant Ishikawajima Kenzai Kogyo Co., Ltd. Figure 2 Figure 3 II Figure 4

Claims (1)

[Scope of Claims] A shield construction method in which an underground structure is constructed by assembling a plurality of segments into a ring in the shield excavator and connecting them in the axial direction in parallel with excavation by the shield excavator, comprising: When assembling segments into an annular shape inside the machine, place the last segment to be fitted outward from the original setting position, and after setting the other segments in an arc shape, remove the last segment to be fitted. A method of assembling segments in the shield construction method, which is characterized by fitting them from both sides and assembling them in a ring shape.