JPH01295997A - Segment for double track-type shield tunnel - Google Patents

Abstract

PURPOSE:To raise the strength stability of double track-type shield tunnel segments by a method in which a tunnel segment is made up of body segments, uprising, skirt, and extending blocks for spatial boundaries, Y- or T-shaped first and second joint segments, and partition segments. CONSTITUTION:Circular-arc segments are assembled on the bottom of a pit in such a way that the axial joint positions of tunnel are not matched between the adjacent existing segments. The extending blocks 3c and 4c of paired joint segments 3 and 4 are combined with a partition segment 5 on the upper end of the segment 2 whose upper part is left to form a space B. The segments 2 are orderly combined with the uprising blocks 3a and 4a of paired joint segments 3 and 4 to form an independent tunnel space A on the upper half of the pit. Balance and stable strength can thus be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a segment used in a double-track shield tunnel.

<Prior Art> Segmented tunnels are known in which a portion of the tunnel body is overlapped and twin tunnels are installed in the vertical direction for the purpose of effectively utilizing underground space.

This type of tunnel has a longitudinally elongated cross-section and horizontally partitions the middle of the hollow space with a partition wall to form two sets of upper and lower independent tunnel spaces.

Problems to be Solved by the Present Invention The conventional shield tunnel has the following structural problems.

(a) Conventional segment tunnels have a structure in which it is difficult to disperse the weight of the tunnel body and loads such as the earthen walls, and they tend to concentrate at the overlap between the upper and lower tunnels.

Therefore, cracks and damage are likely to occur in the overlapping parts and partition walls of the tunnel.

(b) Since the usual shield construction method cannot be applied as is, construction is particularly laborious at the overlapping part, and overall construction efficiency is poor.

(c) In the conventional segment, the bottom plate segment of the upper tunnel is straight, and it is necessary to ensure a thickness that can sufficiently withstand the bending moment caused by the load of trains, automobiles, etc. acting on the upper tunnel. there were.

As the segments become thicker, their weight increases and assembly becomes more labor-intensive, and the assembly device (erector) must be made larger.

Furthermore, although the segments can be made thinner by reinforcing them by inserting a large amount of reinforcing bars into them, there are disadvantages in that not only is the production time-consuming, but the production cost is also high.

OBJECTS OF THE INVENTION The present invention has been made in order to improve the above-mentioned problems, and an object of the present invention is to provide a segment for a double-track shield tunnel as described below.

(a) Segments for double-track shield tunnels that allow easy construction of overlapping parts of tunnel structures.

(b) Segments for double-track shield tunnels that can distribute the load and reliably prevent cracks and damage.

Structure of the present invention> Next, one embodiment of the present invention will be described.

In this example, we will explain a tunnel in which two tunnels with circular cross sections are lined up horizontally and some of them are overlapped, but it can also be used in a structure in which rectangular cross sections are lined up or in a structure in which they are stacked one above the other. .

(a) Overall structure of segment FIG. 1 shows an example of a segment 1 for a shield tunnel, which has two circular parts overlapped with each other and has two upper and lower tunnel spaces A and B.

The segment 1 may be made of either concrete or steel.

2 in the figure is an arcuate segment, which constitutes most of the upper and lower two tunnel shells.

Reference numeral 3.4 denotes two types of joint segments, each of which constitutes a joint between the upper and lower two tunnel bodies, and also constitutes a part of the tunnel outer shell.

Reference numeral 5 denotes a partition segment having an arcuate shape, which is connected to the two junction segments 3.4 to form an independent upper tunnel space A and lower tunnel space B within the segment 1.

When the above segments 2 to 5 are assembled, the outer shape of segment 1 is a figure 8 shape, and the inner shape is such that the upper tunnel space A is circular and the lower part is concave, and the lower tunnel space B is completely circular. form.

Each part will be explained in detail below.

(b) Arc-shaped segment The arc-shaped segment 2 uses a known arc-shaped member having a curvature according to the curve of the designed cross section, and the other segments are formed on the circumferential surface of the arc-shaped segment 2.・There is a bolt hole for connecting to.

(C) Joint segment (Fig. 2.3) The joint segment 3.4 is a block body having a Y-shaped or T-shaped cross section, and each joint segment 3.4 consists of three blocks. .

That is, the standing block 3 that constitutes a part of the outer shell of the tunnel
a, 4a, foot blocks 3b, 4b, and an overhang block 3C14c that supports the partition segment 5.

First, one joint segment 3 will be explained. The continuous surface between the rising block 3a and the bottom block 3b, the continuous surface between the rising block 3a and the overhanging block 3c, and the continuous surface between the bottom block 3b and the overhanging block 3C. The surface is a confluence section 3dll where one end of each block 3a to 3c is butted together.
It exhibits a concave curved surface.

The wall thickness of the proximal end portion of the rising portion 3a connected to the hem portion 3b and the overhanging block 3C increases as it approaches the proximal end.

The end face of the joint block 3 has bolt holes for connecting it to other segments.

Note that each block 4a constituting the other joint segment 4
The shape of the continuous surface of ~4C is the same as that of the joint segment 3.

However, both joint segments 3.4 have different lengths for the corresponding blocks 3a-3C14a-4C.

This is because the joint positions of each segment are shifted and assembled to distribute the load acting on the segment 1.

[Length of each block] In Fig. 3, the confluence 3 of each joint segment 3.4
The lengths from d and 4d to the ends of the rising blocks 3a and 4a are Ll and el, and the lengths from the merging parts 3d and 4d to the ends of the foot blocks 3b and 4b are L2 and e2, and the merging parts When the lengths from 3d and 4d to the ends of the overhanging blocks 3c and 4c are L3 and e3, the length of each block is set to satisfy the following relationship.

LL<f! 1, L2>e2, L3>i! 3 The above length relationship is an example, but the protrusion length of each block is influenced by the relationship such as the division size and number of divisions of the arcuate segment 2,
The dimensions may be set so that the positions of the joints of the segments do not match during assembly.

(d) Compartment Segment The division segment 5 is made of a curved plate and is installed in an upwardly curved state between a pair of joint segments 3.4 having different block lengths.

Both end faces of the partition segment 5 facing the overhanging blocks 3c, 4c of each joint segment 3.4 are wedge-shaped inclined toward the circumferential surface of the tunnel.

Naturally the overhang block 3C1 of each joint segment 3.4
The opposing surface of 4C is also inclined at an angle corresponding to the inclined end surface of partition segment 5.

Construction method Next, a method for assembling the segments will be explained.

(a) Assembling the arcuate segment Segment 1 is assembled in the tunnel immediately after excavation by the shield tunneling machine.

First, the arcuate segments 2 are assembled one after another at the bottom of the mine.

This assembly method is the same as the conventional one.

In this case, the joint positions of the adjacent arcuate segments 2 are shifted so that the joint surfaces in the tunnel axis direction do not coincide with the adjacent existing segments 1 and assembled.

(Mouth) Assembling the Joint Segments Next, a pair of joint segments 3.4 are assembled onto the upper ends of the arcuate segments 2 assembled into a substantially circular shape, leaving the upper part intact.

In this case, the joint segment 4. of the existing segment 1.
Replace the positional relationship with the existing joint segment 4.3 so that the joint position does not match that of the joint segment 4.3.

(c) Assembling compartment segments Each overhang block 3c of a pair of joint segments 3.4
, 4c from above to form a tunnel space B in the mine.

Since the pair of joint segments 3.4 alternate, the joint positions at both ends of the partition segment 5 are assembled offset in the circumferential direction of the tunnel compared to the existing ones.

(d) Assembling the arcuate segments Finally, the arcuate segments 2 are sequentially assembled to each of the rising blocks 3a, 4a of the pair of joint segments 3.4, leading to an independent tunnel space in the upper half of the mine. form.

The arcuate segment 2 forming this tunnel space A is
Assemble the tunnel by shifting its joint position from the adjacent existing joint position in the circumferential direction of the tunnel.

Construct segment 1 one span at a time using the above procedure.

(f) Regarding the strength of the tunnel As described above, in the tunnel constructed using the segments according to the present invention, the joint positions of the segments 2 to 5 are shifted in the circumferential direction of the tunnel.

Therefore, even if a load such as the weight of earth and sand is applied to segment 1, each segment 2 to 5 is not concentrated at the - point.
Can be distributed in groups.

Furthermore, segments 2 to 2, which constitute the lower tunnel space,
5 has an arch structure, it has a high resistance to the weight of earth and sand and the weight of the arcuate segment 2 forming the upper tunnel space A, and it also has a high resistance to the load of trains, etc. acting on the tunnel space A. is large.

Other Embodiments Although the above embodiments have been described with respect to a case in which there are two overlapping tunnel spaces in the vertical direction, it is also possible to apply the present invention to a tunnel that has more tunnel spaces in the longitudinal direction.

Moreover, the present invention can be used not only for shield tunnels having a circular cross section but also for double track tunnels having an elliptical, oval, or rectangular cross section. Since the segments of the present invention are as described above, the following effects can be obtained. is obtained.

(a) Since the joint positions of each segment assembled for each span are shifted in the circumferential direction of the tunnel, stress received from the ground can be dispersed extremely effectively.

(b) Two types of joint segments with different lengths of the block parts are assembled by alternately replacing them along the tunnel direction.

Therefore, compared to a tunnel assembled asymmetrically, a better structural balance is maintained and stable strength can be obtained.

(c) The end faces of the overhanging blocks of the pair of opposing joint segments and the opposing faces of the arc-shaped partition segments are formed to be inclined in a wedge shape.

Therefore, assembly is easy because the partition segments can be installed by sliding them between the opposing joint segments from above.

(d) Since the overlapping part of the tunnel has an arch structure, it is strong against the weight of earth and sand and the weight of trains, etc., which is advantageous in terms of design.

[Brief explanation of the drawing]

Figure 1: Perspective view of a segment according to the present invention Figure 2: Perspective view of a segment constituting the overlapping part of two tunnels Figure 3: Front view thereof Applicant: Taisei Corporation Obayashi Corporation Taiho Construction Co., Ltd. Procedural amendment June 22, 1988 Director General of the Japan Patent Office Yoshi 1) Takeshi Moon1, Indication of the case Japanese Patent Application No. 123613/19832, Name of the invention Segment 3 for double-track shield tunnel, Relationship to the case Patent applicant address Nishi-Shinjuku-chome 25-1, Shinjuku-ku, Tokyo Name
Taisei Corporation Representative: Yasuo Satomi (2 persons) 4, Agent: 105 Address: 9F7, Marufuji Building, 3-1-10 Shinbashi, Minato-ku, Tokyo Contents of amendment

Claims (1)

[Claims] (1) Segments used to construct a shield tunnel that is horizontally partitioned by partitioning material and has multiple independent spaces in the vertical direction, and that constitute the tunnel frame other than the boundary of the tunnel space, and the tunnel. It has a standing block that forms part of the boundary of the space, a foot block that is continuous with the standing block, and an overhanging block that extends inside the standing block and the foot block, and the cross section is approximately A first joint segment exhibiting a Y-shape or a T-shape, a rising block constituting a part of the boundary of the tunnel space, a skirt block continuous with the rising block, and a rising block and the skirt. a second joint having an overhanging block projecting inside the block, having a substantially Y-shaped or T-shaped cross section, and each block having a length different from each block of the first joint segment; A segment for a double-track shield tunnel, comprising a segment and an arch-shaped partition segment interposed between the two types of joint segments described above.