KR20130029524A - Segment body with the prestressed strand cables of a longitudinal direction and the shear keys of a horizontal direction and method constructing the shield tunnel thereof - Google Patents

Abstract

PURPOSE: A segment structure and the construction method of a shield tunnel using the same are provided to provide rigid structure concerning earthquake etc by easily fixing a segment in a consecutive way and increasing a shear stress and an overlapping stiffness. CONSTITUTION: A segment structure and the construction method of a shield tunnel using the same includes following processes. Segments equipping two center passages and two end passages are arranged to the longitudinal direction consecutively. Strands are inserted and fixed consecutively in order to settle only one steel strand in each segment while the longitudinal segment of four columns forms one unit. A segment fundamental reaction wall in which four strands penetrate is formed in the same method. A segment of other column is settled and fixed consecutively with a dig. [Reference numerals] (AA) Tunnel progress direction; (BB) First row; (CC) Second row; (DD) Third row; (EE) Fourth row; (FF) Fifth row; (GG) Sixth row; (HH) Seventh row

Description

Segment structure with the prestressed strand cables of a longitudinal direction and the shear keys of a horizontal direction and method constructing the shield tunnel

The present invention relates to a segment structure having a longitudinal strand and a transverse shear key and a method for constructing a shield tunnel using the same. More specifically, the present invention relates to a segment structure having two center passages and two end passages. Arrange sequentially in each row adjacently in the longitudinal direction, with four rows of longitudinal segments as one unit to insert, tension, and anchor the strands, and to ensure that only one strand is anchored in each segment so that only those segments are fixed and fixed. The remaining three strands are settled and fixed sequentially in the same way as the segments located in the other rows through the passageway, thereby forming a segment-based reaction wall through which all four strands penetrate, and at the same time structurally stable foundation reaction wall Segment of different columns by the remaining three strands Fixation and fixation are facilitated sequentially, and by repeating the above process, fixation and fixation of the segment foundation reaction wall and thus other columns is sequentially performed with excavation.

The assembly of the segments is efficient and economical, which is a useful invention for shield tunnels.

The shield tunnel method is a method of assembling and dismantling segments by a shield tunnel drilling device and at the same time assembling a supporter.

More specifically, the shield tunnel method is excavated by the rotation of the tip cutter head of the shield tunnel excavator, and the soil produced by the excavation is disposed of and discharged out through a screw conveyor provided in the shield tunnel excavator. It is a process consisting of a series of systems for assembling segments that are supported by space.

Shield tunnel excavators are generally well known.

Among them, the shield tunnel boring device described in Patent Publication No. 93-006410 will be described as follows. (See Fig. 1)

The shield tunnel excavator 10 is largely composed of a cutter head 16, a head portion 22, a shield body 12, and a tail portion 24.

An opening 86 is formed at an upper portion of the partition 30, and a lid 88 hinged to the partition 30 is disposed at the opening 86. The lid 88 is connected to the piston rod 92 of the cylinder 90 attached to the diaphragm 32 via the arm 94.

The lid 88 normally closes the opening portion 86 by the cylinder 90, but the earth pressure applied to the space portion between the partition 30 and the cutter head 16 is set in the cylinder 90. When the pressure is exceeded, the opening 86 is opened to be driven toward the diaphragm 32 against the pressure of the cylinder 90 so as to introduce the sand into the grinding chamber 28.

In the grinding chamber 28, the rotor 96 and the stator 98 which comprise the crusher which crushes the comparatively large gravel which entered the grinding chamber 28 are arrange | positioned. The rotor 96 is attached to the rotation shaft 68, and the stator 98 is attached to the partition wall 30 below the rotor 96. High pressure water is also sent to the grinding chamber (28) via the feed pipe (100), and the supplied water is discharged to the rear of the shield body (12) via the discharge pipe (102) together with the soil in the grinding chamber (28). do. At the start of drilling, the propulsion jacks 14 of the drilling device 10 have the piston rods 46 and 48 being retracted into the cylinder 40.

In this state, the excavator 10 receives the propulsion force of the shield body 12 by the propulsion jacks 14, and each motor 70 of the rotating mechanism 18 is rotated, and the rotation of each motor 70 is reduced. The cutter head 16 is rotated by being transmitted to the face plate 58 via the 72, the tooth 74, the tooth 76 and the rotation shaft 68. It is pushed while being excavated by the rotation of the cutter head 16. The excavated earth and sand enters the space in front of the partition wall 30, and then enters into the grinding chamber 28 via the opening 86 of the partition wall 30 and then discharges the discharge pipe 102 from the grinding chamber 28. It is discharged with water via diesel. As the shield body 12 is advanced, the segment 104 is disposed in the space formed behind the shield body 12.

It looks at the problem of the prior art Patent No. 10-0936471 constructed by the shield tunnel drilling device as described above. (See Fig. 2)

The inventors and applicants of registered patent 10-0936471 are the same as the inventors and applicants of the present application.

Circular shield support ball (10) consists of seven segments and is fixed by the key (K) segment.

Four sides of each segment have a drainage flow path 16 and a drainage structure provided with a water stop 18 before and after the drainage flow path 16. By installing the water repellent agent, even if penetrated through the junction while preventing the penetration of the infiltration through the drainage flow path 16 is a structure that is to be discharged out.

As described above, Patent No. 10-0936471 is a structure having a cross-sectional joint where all the end joints of 7 segments meet in one plane, even though the permeation prevention and treatment are perfectly achieved by the drainage structure. Since there is no longitudinal binding structure (e.g., steel wire structure) to connect and bind, there is a problem that the cross-section joint is easily shifted up and down even by the biasing caused by the ground. The impact of the earthquake is greater and more serious than the problem of bias. Absolute preparations for earthquakes are required. Legally mandatory seismic design is considered to reflect the seriousness of this problem.

Since the volleyball structure of Patent No. 10-0936471 also assumes that the segment joints are not arranged in a zigzag form, it is considered to be the first priority to connect and bind the cross-sectional joints with each other.

⒜ In the present invention, two center passages and two end passages are arranged in sequence in each row adjacent to each other in the longitudinal direction, and the strand is inserted and tensioned using four rows of longitudinal segments as one unit. ㆍ Settle and fix only one strand in each segment so that only the segment is settled and fixed.The remaining three strands are settled and fixed sequentially in the same way as above. Segment base reaction wall through which all the two strands are penetrated is formed, and the remaining three strands make it easier to fix and fix the segments of other rows sequentially based on the structurally stable foundation reaction wall. Settling and fixing of the segment foundation reaction wall and thus other columns Its purpose is to make the assembly of the segment more efficient by being done with drilling.

전단 Shear key is formed in the transverse direction of each segment, and the longitudinal line is arranged in a zigzag shape and the strands are arranged to form a segment-based reaction wall in the longitudinal direction. This is another purpose to increase the rigid segment structure that is durable against earthquakes, etc.,

Another objective is to minimize the eccentric moment due to the bias of earth pressure by placing two center passages close to the center line and two end passages close to both ends.

The configuration of the present invention is as follows. (See Figures 4a, b, c, d)

In the present invention, two center passages (10) and two end passages (20) are formed at right angles to the cross-section joint, but the two center passages (10) are provided with stranded wire passages (F3, F4) and strands. While the fixing units G1 and G2 are formed, the strand wire fixing units G1 and G2 are located in the direction of the tunnel excavation, and the two end passages 20 include the strand wire inserting and fixing space portions E1 and E2. While the strand line passages F1 and F2 are formed, the strand line insertion / fixing space portions E1 and E2 and the strand line fixing portions G1 and G2 are located in opposite directions, while Qa = Basic set-up A (A1 = A2 = A3 = A4) with a shear key having the relation Pa, Qb = Pb, Qc = Pc = 2Qa = 2Pa is formed, and A1 and A4 are in contact with the lower end and placed on A1. Arrange A2 → B and A3 → C on A4 in this order, and insert a K segment between B and C, but the B, C, and K segments are the same as the basic set A. The segment is formed at the lower Qa of the Q straight line, and the C segment is formed at the upper Qa of the Q straight line by Qd longer than Qa, and the corresponding K segment is formed at the upper and lower Qa of the Q straight line by Qd shorter than Qa. Segment structure having a longitudinal strand and a transverse shear key.

In addition, the strand anchoring unit G1, G2 has a conical hole corresponding to the tip male cone of the strand, and the strand insertion / fixing space portions E1, E2 have a space portion corresponding to the trailing edge of the strand. A segment structure having a directional strand and a transverse shear key.

A segment structure having a longitudinal strand and a transverse shear key, wherein a flow path groove and a water-expansion index agent are formed at each segment four-faced joint.

The shield tunnel of the present invention has a circular cross section as shown in FIG. The number of segments forming a circular cross section is an odd number. Seven or five are preferred.

For convenience of description, it will be described with seven segments.

First, the shape of each segment is demonstrated.

The present invention is composed of a basic segment A, a key segment K, and a B and C segment adjacent to the K segment. (A1 = A2 = A3 = A4.)

As shown in Fig. 4A, the basic segment A has a structure in which shear keys having a relationship of Qa = Pa, Qb = Pb, and Qc = Pc = 2Qa = 2Pa with respect to P and Q lines are formed in grooves and irregularities.

As shown in Fig. 5A, the segments of each row are assembled and arranged in a zigzag form.

Like the first column, the third column, and the fifth column, the odd columns are arranged in the same position, and the even columns of the second column, the second column, and the sixth column are located in the center line of the A segment. That is, it is located down by 1/2 of A.

The K segment is assembled wedge-shaped as a key segment.

The K segment is the same as the basic segment A, but is formed shorter by Qd than Qa in the upper and lower Qa of the Q straight line.

The B and C segments are adjacent to the K segment and differ only from the basic segment A only in the adjacent plane. The B segment is formed at the lower Qa of the Q straight line, and the C segment is longer than Qa at the upper Qa of the Q straight line.

Zigzag assembly of the segments is made by two adjacent segments at Qc and Pc. For example, two Qa are assembled adjacent to each other in Qc (see Fig. 5A).

As described above, although the structure of each segment is only slightly different from the K segment and the adjacent B and C segments, the segment is easy to manufacture because it is not significantly different from the basic A segment.

Next, the twisted line penetration path of each segment is demonstrated.

In each segment, two center passages 10 and two end passages 20 are formed parallel to each other at right angles to the cross-sectional joint.

The two center passages 10 are close to the center line of the segment, and the two end passages 20 are symmetrical about the center line while being close to the ends. Since the strand should pass through the center passage 10 through the end passage 20, the distance between the center line and the end is the same.

The stranded wire starting from the insertion / fixed space portions E1 and E2 of the end passage 20 passes through the stranded wire anchoring portions G1 and G2 of the center passage 10 as shown in FIGS. 5A and 5B. It is a zigzag connection structure settled in G1, G2). In addition, the closer the strand line fixing portions G1 and G2 of the center passage 10 are to the center line, the more the eccentric bending moment due to earth pressure can be minimized, and a rigid structure of the segment can be formed.

The insertion / fixed space portions E1 and E2 are formed on one side of the end passage 20, and the strand wire fixing portions G1 and G2 are formed on one side of the center passage 10, and are located in opposite directions.

The strand wire insertion / fixing space portions E1 and E2 are spaces into which a new strand wire is inserted.

In the conical holes of the stranded wire anchoring sections G1 and G2, the male cone of the stranded wire is fixed, and the trailing edge of the stranded wire is fixed to the stranded wire insertion / fixing spaces E1 and E2.

The water-expandable index member may be formed around the channel grooves in the center at all the contact portions where the segments and the segments contact each other.

⒜ In the present invention, two center passages and two end passages are arranged in sequence in each row adjacent to each other in the longitudinal direction, and the strand is inserted and tensioned using four rows of longitudinal segments as one unit. ㆍ Settle and fix only one strand in each segment so that only the segment is settled and fixed.The remaining three strands are settled and fixed sequentially in the same way as above. Segment base reaction wall through which all the two strands are penetrated is formed, and the remaining three strands make it easier to fix and fix the segments of other rows sequentially based on the structurally stable foundation reaction wall. Settling and fixing of the segment foundation reaction wall and thus other columns Since the configuration is made with the excavation, the assembly of the segment has an efficient and economical effect.

전단 Shear key is formed in the transverse direction of each segment, and the longitudinal lines are arranged in a zigzag shape and the strands are arranged to form a segment-based reaction wall. Overlap stiffness is increased, resulting in a rigid segment structure with high durability against earthquakes.

⒞ Since two center passages are close to the center line and two end passages are close to both ends, the eccentric moment due to eccentricity of earth pressure is minimized and structurally stable.

1 is a cross-sectional state diagram of a shield tunnel excavator generally used.
2 is a perspective view of a conventional shield segment
3 is a circular cross-sectional view of the shield segment of the present invention.
4A is a perspective view of a basic segment A of the present invention.
4B is a perspective view of the B segment of the present invention.
4C is a perspective view of the C segment of the present invention.
4d is a perspective view of the K segment of the present invention;
4E enlarged view of FIG. 4A
Fig. 5a is a plan view showing a state in which segments of the present invention are arranged in a zigzag shape;
FIG. 5B is a schematic diagram illustrating passage and settling of the strand for the A1 segment in the fourth column of FIG. 5A. FIG.
Figure 6a is a perspective view of a segment used in the conventional bolt method
FIG. 6B is a cross-sectional view of the joint of FIG. 6A joined by bolts. FIG.

The construction method of the shield tunnel using the segment structure having the longitudinal strand and the transverse shear key of the present invention will be described in detail with reference to the accompanying drawings.

First, the basic concept for the insertion and fixing of the stranded wire in the zigzag segment of the present invention will be described.

The length of the strand is approximately equal to the length of four longitudinal segments arranged. This is because the stranded wire connects and fixes the four longitudinal segments in one unit. One unit of the strand is a four segment row. As shown in Fig. 5B. FIG. 5B is a schematic diagram of four strands for A1 in the fourth row in the segment assembly of FIG. 5A.

For example, the stranded wire starting from the first row E2 in Fig. 5B is tensioned and settled in the fourth row G2. Four strands pass through A1 in the fourth row. At this time, the starting point and the fixation point of the four strands passing through A1 in the fourth column are different. Settled in column A1 of the fourth row is the only stranded ship starting from the first row. This strand secures A1 in the fourth row first. In the state where A1 of the fourth column is fixed in this manner, the strands start in the second row, the third row, and the fourth row. In the state where A1 of the fourth column is not fixed, the strands of the second, third, and fourth columns cannot pass through A1 of the fourth column. This is because it is virtually impossible to pass through the A2 in the fifth row, which is not fixed in the second row of the strands.

A1 of the fourth row must be fixed by the stranded ship starting from the first row E2, so that the stranded ship starting from the second row passes through A1 of the fourth row and is then settled in the fifth row. This is because the fifth column is possible only when the fourth column is fixed. In addition, in order for the stranded ship starting from the third row to be able to settle the sixth row, the fifth row and the fourth row may be fixed at the same time.

All segments pass through all four strands, but only one strand is settled in that segment, and the remaining three strands pass through A1 in the fourth row and are subsequently settled in the next row. In other words, segment foundation reaction wall is made by the settlement of the strand, and then another foundation reaction wall is repeatedly formed in the direction of excavation while strengthening the foundation reaction wall by the three strands.

According to Fig. 5B, the four strands in the fourth row are the strands starting from the first row, the second row, the third row, and the fourth row. In other words, the stranded ship that has been tensed and settled in the fourth row G1 starting from the first row E2 and that has left the second row E2 is the stranded ship that has been tensed and settled in the fifth row G1. Similarly, the stranded wire is tensioned and settled in the third row E1 to the sixth row G2, and tensioned and settled in the fourth row E1 to the seventh row G2.

As described above, the strands inserted into the four throughways of the fourth row are the strands starting from the first row, the second row, the third row, and the fourth row, and at the same time relying on the fourth row, the fifth row, the sixth row, and the seventh row. It is a supporting member which fixes and fixes heat sequentially. It is for this reason that A1 in the fourth column is called the base reaction wall.

In addition, the shear stress of the shear key increases as the segments of each row are arranged in a zigzag, and the four strands are fixed and fixed only one for each row. Therefore, the overlapping stiffness of the strands increases, which is robust against earth pressure and earthquake. Construction is facilitated because it serves as a foundation reaction wall for the segments that are subsequently constructed while forming the structure. In addition, the length of the strand is the length at which the tensile force is maximized while the loss is minimized.

For convenience of description, seven segments have been described, but the number of segments is the same concept as the above, whether the number of segments is five or seven.

However, the foundation reaction walls are not provided in the first row, the second row, and the third row of FIG. 5B. This is inevitable because the segments and strands are assembled in a zigzag.

For the first row, the second row, and the third row, the conventional bolt method and the assembly method of the present invention will be performed in parallel. Since the conventional bolt method is a widely used method, only the outline thereof will be described briefly by Korean Patent Laid-Open Publication No. 10-2004-0026598.

As shown in FIG. 6A, a segment of the publication No. 10-2004-0026598 has a longitudinal bolt box 13 and a transverse bolt box 12. Only the transverse bolt box 12 is connected in the transverse direction and the longitudinal bolt box 13 is omitted and the longitudinal strand line passage of the present invention is formed in the longitudinal direction. First, the lateral bolt box 12 is bolted, and then the stranded wire is tensioned and fixed to the longitudinal stranded wire passage in the same manner as above.

6B shows a state in which the lateral bolt box 12 is in contact with each other and fixed as a fixing bolt 7 and a nut 8.

Now, a method for constructing a shield tunnel using a segment structure having a direction strand and a transverse shear key according to the present invention will be described.

세그먼트 Seven segments are arranged in the tunnel tunnel space with the same shape and structure as in claim 1, and A1 → A2 → B, and A4 → A3 → C, respectively. Arranging and positioning so as to be in a state, and inserting and fixing a K segment between B and C to form a first row;

각 Arrange and position each segment of the second column so as to be circular in the same manner as the first column, adjacent to the first column, with the end of A1 of the second column in the center line of A1 of the first column so that the first row and the second row are half of A1. Arranging the rows alternately, and fixing the segments by inserting fixing bolts into the transverse bolt boxes 13 of the first row and the second row;

(2) Arrange and position each segment of the third column in a circular state adjacent to the second column with the same height as the first column, with the second row and the third row staggered by half of A1. Fixing each segment by inserting fixing bolts into three rows of lateral bolt boxes 13;

(2) Insert a strand into the strand line insertion / fixed space portion E2 of each segment (A1, A2, B, K, C, A3, A4) in the first row, and then (F3-G1) → (E2- in the second row) F2) → After passing through (F3-G1) in the fourth row, the stranded wire is tensioned and fixed to the strand anchorage part G1 of each segment (A1, A2, B, K, C, A3, A4) located in the fourth row. After fixing the segments located in the fourth row, insert the strand into the strand-inserting / fixing space portion E2 of each segment in the second row, and insert (F3-G1) in the third row → (E2-F2) in the fourth row → the fifth row. After passing through (F3-G1), the stranded wire is tensioned and fixed to the stranded wire anchorage part G1 of each segment (A1, A2, B, K, C, A3, A4) located in the fifth row, and each segment located in the fifth row is In the same manner as described above, each segment positioned in the sixth and seventh columns in the order of the sixth and seventh columns by inserting the stranded wire into the strand-inserting and fixing space portion E1 of each segment in the order of the third row and the fourth row ( Fixing each of the segments located in the sixth row and the seventh row by tensioning and anchoring the stranded wire to the stranded wire fixing unit G2 of A1, A2, B, K, C, A3, and A4);

세그먼트 Each segment of the fifth row is fixed by the insertion and tension of the second row of strands, and each segment of the sixth row is fixed by the insertion and the tension of the third row. Fixing each segment located in the eighth column in the same manner as the first row by the insertion and tension of the fifth strand of the strand in the fixed state;

세그먼트 Each segment anchored in column 9 is inserted and tensioned in the sixth row of strands, and each segment anchored in column 10 is anchored and inserted in the seventh row. and a step of assembling the shield tunnel sequentially by inserting and tensioning the n-3 rows of stranded wires.

In addition, a segment male having a directional strand and a transverse shear key, characterized in that a male tip of the strand is fixed in a conical hole formed in the strand anchoring portions G1 and G2, and the rear fixed portion of the strand is fixed to the strand insertion / fixing space portions E1 and E2. Shield tunnel construction method using

G1, G2; Stranded anchorage
E1, E2; Strand insertion and fixed space part
F1, F2, F3, F4; Stranded passage
10; Center passage
20; End passage

Claims (5)

Two center passages (10) and two end passages (20) are formed at right angles to the cross-section junction, and the two center passages (10) are provided with the strand line passages (F3, F4) and the strand anchorage portion (G1). , G2) is formed, and the strand wire anchoring portions G1 and G2 are located in the direction of the tunnel excavation, and the two end passage passages 20 include the strand wire insertion / fixing space portions E1 and E2 and the strand wire passageway. While the F1 and F2 are formed, the strand insertion and fixing space portions E1 and E2 and the strand anchor fixing portions G1 and G2 are located in opposite directions, while Qa = Pa and Qb = with respect to the P and Q straight lines. A basic piece A (A1 = A2 = A3 = A4) having a shear key having a relationship of Pb, Qc = Pc = 2Qa = 2Pa is formed, and A1 → A4 is contacted on the lower end with A2 → B and Arrange A3 → C on A4 in order, and insert K segment between B and C, but B, C, and K segments are the same as basic set A, but B segment In the lower Qa of the Q straight line, and the C segment is formed by Qd longer than Qa in the upper Qa of the Q straight line, and the corresponding K segment is formed by Qd shorter than Qa in the upper and lower Qa of the Q straight line. Segment structure having a longitudinal strand and a transverse shear key
The method of claim 1
Longitudinal direction characterized by a conical hole corresponding to the male cone of the stranded wire in the strand anchoring parts G1 and G2, and a space corresponding to the rear fixed part of the stranded wire in the strand insertion and fixing space parts E1 and E2. Segment Structure with Strands and Transverse Shear Keys
The method according to claim 1 or 2
A segment structure having a longitudinal strand and a transverse shear key characterized in that a flow path groove and a water-expansion index agent are formed at each segment four-sided junction.
세그먼트 Seven segments are arranged in the tunnel tunnel space with the same shape and structure as in claim 1, and A1 → A2 → B, and A4 → A3 → C, respectively. Arranging and positioning so as to be in a state, and inserting and fixing a K segment between B and C to form a first row;

각 Arrange and position each segment of the second column so as to be circular in the same manner as the first column, adjacent to the first column, with the end of A1 of the second column in the center line of A1 of the first column so that the first row and the second row are half of A1. Arranging the rows alternately, and fixing the segments by inserting fixing bolts into the transverse bolt boxes 13 of the first row and the second row;

(2) Arrange and position each segment of the third column in a circular state adjacent to the second column with the same height as the first column, with the second row and the third row staggered by half of A1. Fixing each segment by inserting fixing bolts into three rows of lateral bolt boxes 13;

(2) Insert a strand into the strand line insertion / fixed space portion E2 of each segment (A1, A2, B, K, C, A3, A4) in the first row, and then (F3-G1) → (E2- in the second row) F2) → After passing through (F3-G1) in the fourth row, the stranded wire is tensioned and fixed to the strand anchorage part G1 of each segment (A1, A2, B, K, C, A3, A4) located in the fourth row. After fixing the segments located in the fourth row, insert the strand into the strand-inserting / fixing space portion E2 of each segment in the second row, and insert (F3-G1) in the third row → (E2-F2) in the fourth row → the fifth row. After passing through (F3-G1), the stranded wire is tensioned and fixed to the stranded wire anchorage part G1 of each segment (A1, A2, B, K, C, A3, A4) located in the fifth row, and each segment located in the fifth row is In the same manner as described above, each segment positioned in the sixth and seventh columns in the order of the sixth and seventh columns by inserting the stranded wire into the strand-inserting and fixing space portion E1 of each segment in the order of the third row and the fourth row ( Tightening and anchoring the strand to the strand anchoring unit G2 of A1, A2, B, K, C, A3 and A4 to fix each segment located in the sixth and seventh rows;

세그먼트 Each segment of the fifth row is fixed by the insertion and tension of the second row of strands, and each segment of the sixth row is fixed by the insertion and the tension of the third row. Fixing each segment located in the eighth column in the same manner as the first row by the insertion and tension of the fifth strand of the strand in the fixed state;

세그먼트 Each segment anchored in column 9 is inserted and tensioned in the sixth row of strands, and each segment anchored in column 10 is anchored and inserted in the seventh row. shielding tunnels are sequentially assembled by inserting and stretching the n-3 rows of stranded wires; a method of constructing a shielded tunnel using a segment structure having a directional strand and a transverse shear key
The method according to claim 4
A segment structure having a direction strand and a transverse shear key is characterized in that a male tip of the strand is fixed to a conical hole formed in the strand anchoring portions G1 and G2, and the rear fixed portion of the strand is fixed to the strand insertion / fixing space portions E1 and E2. Construction method of shield tunnel using

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