JP3196126B2 - Composite structural segment for large section rectangular shields - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite structural segment for a rectangular shield having a large cross section, which is used for lining a rectangular shield having a large cross section having a width of 7 m or more and has no pillar in the middle.

[0002]

2. Description of the Related Art A conventional shield method is generally mainly implemented as a circular shield. Although a rectangular shield is implemented, the conventional rectangular shield is merely implemented in a common groove or the like, and has a small cross section of about 5 m in width and about 4 m in length. In addition, since the cross section has a cross section supported by columns, the cross section force such as a bending moment generated in the segment is small, so that the lining by the reinforced concrete (hereinafter referred to as RC) segment was easy.

[0003] Conventionally, the lining of the shield is also performed with a lightweight steel segment. In recent years, although the technical fields are different, in order to reduce the weight of a bridge girder, a girder having a composite structure of steel-framed reinforced concrete (hereinafter abbreviated as SRC) has been developed. The bridge of the SRC composite structure has an RC structure on the compression side of the member and an S structure on the tension side, omitting the concrete on the tension side, and enabling a light weight structure with the same proof stress.

[0004]

[Problems to be solved by the present invention]

(a) Even in a one-lane ramp such as a road, when the lateral dimension of the tunnel is about 7 to 12 m, the bending moment is dominant in the section force generated in the rectangular shield segment. For example, among the generated sectional forces, especially the bending moment increases with the square of the tunnel width unless there is an intermediate column, and becomes a factor that determines the scale of the tunnel body cross section. Therefore, when a rectangular shield having a large cross section is covered with the RC segment, the girder height (frame thickness) is considerably large. As the girder height increases, the weight of the segments inevitably increases. On the other hand, the weight of one piece of a segment depends on the capacity of the erector.
Since the number is limited to 0 to 20 tons, when the girder height increases as described above, the size of one piece must be reduced, and the number of segment divisions increases. When the number of segments is increased, the number of joints is increased, the structure becomes weak, and the number of assembling steps is increased, which is troublesome. Thus, the larger the lateral dimension of the tunnel, the more the rectangular shield
The lining with the C segment becomes difficult. (b) When lining the rectangular shield with steel segments, the weight is reduced, but the deformation is increased due to low rigidity. Also, when the excavated cross section of the rectangular shield becomes large,
Naturally, the thrust of the shield jack also increases, and in the case of a steel segment, it is necessary to reinforce the thrust received by the shield jack, and this measure is very expensive. (c) Conventionally, there has been no case in which the structural characteristics of a bridge having an SRC composite structure are employed in the configuration of a shield segment for practical use. However, the distribution diagram of the sectional force and the bending moment generated in the shield tunnel having a rectangular section has a certain form as shown only partially in FIG. Therefore, if the bending tension side is made of a steel frame and the bending compression side is made of a composite (composite) structure of a reinforced concrete structure, a reasonable lining structure can be obtained. (d) Accordingly, an object of the present invention is to reduce the weight and size of a rectangular shield segment having a large cross section, and more specifically, a segment piece having a composite structure of a steel structure and a reinforced concrete structure in the same cross section. The purpose of the present invention is to provide a structural integration of a steel frame part and a reinforced concrete part in the manufacture of a composite structure, that is, to provide a composite structural segment for a rectangular shield having a large cross section, in which a connecting means necessary for a composite or composite structure is devised. .

Incidentally, the functions required for the synthetic segment for a rectangular shield having a large cross section required by the present invention are summarized as follows.
It looks like the following. It has the function of structurally integrating the S-shaped part and the RC-shaped part. The joint between the S-structure and the RC-structure is 1-2 kg / cm ²
It has a sufficient water stopping function for a moderate water pressure.

[0006] The joining means for combining the S and RC structures has a structural characteristic capable of effectively transmitting the sectional force (M, N, Q) generated in the segment. Each of the segment pieces is divided into a number and a size such that an assembling operation can be performed in a segment assembling portion in the shield.

[0007]

As a means for solving the above prior art problems SUMMARY OF THE INVENTION The synthetic structural segment for rectangular shield large section according to a first aspect of the present invention, to form the corners of a rectangular shield In a segment composed of a combination of four pieces and at least four side pieces connecting between the corner pieces, the side piece has a bending tension side portion made of steel. bending compression side portion that is a composite structure of steel reinforced concrete formed by integrating the steel and reinforced concrete structurally with is composed of reinforced concrete, the side portions
The steel frame on the bending and pulling side of the piece is made of H-section steel.
The inner flange of the H-section steel is bent
Located at the boundary with the reinforced concrete
Stat dowel or channel protruding from the side flange
Fixing members, such as steel bars, are fixed in the reinforced concrete.
The fixing length is embedded .

[0008]

[0009]

[0010]

The pieces 5 to 8 at the sides resist the tensile stress due to the bending moment with the steel frame 11 which is strong in tension and the compressive stress with the reinforced concrete 12 which is strong in compression, and do not require any intermediate pillars. . And since the bending tension side part was made into the steel frame 11, compared with the case where the whole is made into a reinforced concrete structure, it becomes considerably lighter.

The steel frame 11 is fixed by the fixing length inserted into the reinforced concrete 12 and the function of the fixing member.
Alternatively, the structural integration (composite structure) with the reinforced concrete 12 is achieved by the function of the stat dowel 22 or the channel steel 23 or the like. Since all the joints 9 between the segment rings are made of a steel frame, they can be handled according to general steel structure joints.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
In the rectangular shield segment shown in FIG.
This is an example of a lining example of a one-lane lamp having a bending moment of about 200 ton · m.
It has a width of 9.6m, a height of 6.6m and a frame thickness of 7
For a large cross section of 0 cm. This rectangular shielding segment has four L-shaped pieces 1 forming four corners of a rectangle.
And four pieces 5 to 8 forming a straight line on the side connecting the pieces 1 to 4 at the corners.

The position of the joint 9 between the pieces 1 to 4 at the corners and the pieces 5 to 8 at the sides is as shown in FIG.
It is the boundary between the positive and negative bending that occurs. The corner pieces 1 to 4 are manufactured as a reinforced concrete structure having the strength to withstand the positive and negative bending moments (see FIG. 2) (FIG. 1). On the other hand, in the side pieces 5 to 8, the bending tension side portion (about the inside half of the frame thickness) by the action of the bending moment (see FIG. 2) is made of a steel frame 11 such as H-section steel, and the bending compression side portion. The steel frame 11 is manufactured as a steel-framed reinforced concrete composite structure segment in which the steel frame 11 is integrated with the reinforced concrete 12 and is combined with the reinforced concrete 12.

Next, the specific structure and manufacturing method of the segment will be described. 3 and 4 show an embodiment in which a T-shaped steel 17 is used for a steel frame. Ring width (axial length) is 1
This is an example of a segment having a m and a frame thickness of about 70 cm. The three T-shaped steel members 17 used as the steel frames serving as the main structural elements on the positive bending side have a composite structure that can sufficiently cope with the variation of the sectional force that changes from the positive bending to the negative bending illustrated in FIG. The flanges are arranged in a plane, and the tip of the web portion 17a having a length of about 45 cm is inserted into the reinforced concrete 12 of about 10 cm (at least 10 cm or more), which is the anchoring length. A more detailed structure is shown in FIG. A notch 19 is provided at the tip of the web portion 17a, and a stirrup streak (shear reinforcing bar) 18 of the reinforced concrete 12 is inserted into the notch 19 to ensure a penetrating state. Moreover,
Two angles 20, 20 as fixing members are fastened in a symmetrical arrangement with bolts 25 and nuts 26 on both sides of the front end of the web portion 17 a. The three side-by-side T-beams 17 are also welded to each other at the butted portions of the flanges as necessary.

Next, in the embodiment shown in FIG. 5, an H-shaped steel 21 is used for the steel frame, and a stat dowel 22 is used for integral joining with the reinforced concrete 12. An inner flange 21a of the H-section steel 21 is disposed at a boundary portion with the reinforced concrete 12, and a plurality of stat dowels 22 are protruded in a line at a constant pitch at a substantially central position on the outer surface of the flange 21a. H-section steel 21 arranged in three parallel
The angle 2 embedded in the reinforced concrete 12 in order to close the gap generated as a result of the inner flanges 21a being evenly arranged over the entire width of the segment piece.
7 are installed. The angle 27 is joined to the flange 21a of the H-section steel by means of welding or bolting. Therefore, the angle 27 also works for the structural integration of the H-section steel 21 and the reinforced concrete 12. Further, the angle 27 also functions as a spacer by placing the stirrup streaks 18 when arranging the reinforcing bars of the reinforced concrete 12.

FIG. 6 shows the stat dowel 22 shown in FIG.
Channel member 2 having a plurality of openings 23a for increasing the effect of joining with concrete as a fixing member instead of
3 shows an embodiment using No. 3. Channel steel 23
Is a flange 2 of the H-section steel 21 by means of welding or bolting.
1a. Next, FIG. 7 shows a joint 9 between pieces on the premise of the structure of each segment piece described above. First of all, the joints of the corner pieces 1 to 4 are
Using an H-section steel or the like having a specification corresponding to the steel frame 11 (T-section steel 17 or H-section steel 21) in the side pieces 5 to 8,
The steel frame 14 is integrated with the pieces 1 to 4 so as to face the steel frame 11. Therefore, the joint 9 is brought into contact with a structure similar to a general steel structure joint by joining the two steel frames 11 and 14, applying the gusset plate 15, and strongly fastening the bolts 16.

The rectangular shield composite structure segments 5 to 8 having the above construction are examples of lining of one-lane lamps with an earth covering of 0 to 20 m and a bending moment of 200 ton · m.
When these are all reinforced with RC structures, the frame thickness (girder height) is 1
m, which is very heavy. However, when the pieces 5 to 8 at the side portions are manufactured by the SRC structure as in the above embodiment, the frame thickness can be reduced to about 70 cm, and the maximum weight of the pieces can be reduced to about 7 tons. That is, the frame thickness is reduced by 30%, and the piece weight can be reduced to less than half.

[0018]

According to the large-section rectangular shielding segment of the present invention, the structure can effectively cope with the large cross-sectional force generated, and it is lightweight and easy to assemble. It contributes to the realization of rectangular shield construction.

[Brief description of the drawings]

FIG. 1 is a front view of a rectangular shield segment according to the present invention.

FIG. 2 is a distribution diagram of a sectional force acting on a segment.

FIG. 3 is a perspective view showing a first embodiment of the composite structure segment.

FIG. 4 is an enlarged perspective view showing a main part of the segment of FIG. 3;

FIG. 5 is a perspective view showing a second embodiment of the composite structure segment.

FIG. 6 is a perspective view showing a third embodiment of the composite structure segment.

FIG. 7 is a sectional view showing a joint between pieces.

[Explanation of symbols]

 1-4 Pieces at corners 5-8 Pieces at sides 11 Steel 12 Reinforced concrete 17 T-section 17a Web section 18 Stirrup 20 Angle 21 H-section 21a Inner flange 22 Stat dowel 23 Channel section 9 Joint 14 Steel 15 Gusset plate 16 Bolt

──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Yuichi Komura 2-5-1 Minamisuna, Koto-ku, Tokyo Inside Takenaka Corporation Technical Research Institute Co., Ltd. (72) Inventor Yoshifumi Fujii 8-1-1 Ginza, Chuo-ku, Tokyo No. Takenaka Civil Engineering Co., Ltd. (72) Inventor Hiroyoshi Tagawa 8-2-1-1, Ginza, Chuo-ku, Tokyo Stock Company Civil Engineering Co., Ltd. (72) Yasushi Kanzaki 8-21-1, Ginza, Chuo-ku, Tokyo Takenaka Co., Ltd. Civil engineering (72) Inventor Kazuki Wakita 8-21-1, Ginza, Chuo-ku, Tokyo Co., Ltd. Takenaka Civil Engineering Co., Ltd. (56) References JP-A-6-146796 (JP, A) JP-A 4-112995 (JP, U) JP-A-4-26298 (JP, U) JP-A-3-18298 (JP, U) (58) Fields studied (Int. Cl. ⁷ , DB name) E21D 11/08 E21D 11/14

Claims (1)

(57) [Claims] 1. A segment comprising a combination of four pieces forming a corner of a rectangular shield and at least four pieces of a side portion connecting between the pieces at the corner, wherein: this piece portion is configured bending tensile portion in steel, bending compression side portion which is a composite structure of steel reinforced concrete formed by integrating the steel and reinforced concrete structurally with is constructed of reinforced concrete
And the steel frame on the bending-pulling side of the side piece is H-shaped
The inner flange of the H-section steel is bent
Located at the boundary between the compression side and reinforced concrete
Stat dowels projecting from the inner flange or
The anchoring member such as channel steel is made of the reinforced concrete
A synthetic structural segment for a rectangular shield having a large cross section, characterized in that it is embedded in a predetermined fixing length .