JP2001220999A - Shield tunnel lining body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shield tunnel lining body capable of positioning with ease and also transmitting the shearing force between segment assemblies in assembling the shield tunnel lining body with a ring-like segment assembly butting against another ring-like segment assembly. SOLUTION: In a shield tunnel lining body comprising a plurality of ring-like segment assemblies, which are integrated by introducing pre-stress in the circumferential direction, axially connected to each other by inserting PC steel material in the duct penetrating segments in the axial direction and introducing pre-stress in the axial direction by making the PC material become intense, a plurality of projections 32 are provided in the end face 31 connected to another ring-like segment assembly 40 in a ring-like segment assembly 30 so as to be projected to the other segment assembly 40 from the segment assembly 30, and a plurality of recessed sections 42 capable of containing each projection 32 are provided in the end face 41 of the other segment assembly 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield tunnel lining body constructed by assembling a plurality of segments in a circumferential direction and an axial direction. It relates to the shield tunnel lining to be introduced.

[0002]

2. Description of the Related Art Generally, the lining of a shield tunnel is
It is built by assembling factory-produced segments underground. The assembled lining body must have sufficient strength to withstand the earth pressure and water pressure acting from the ground around the tunnel, and shall not cause excessive deformation, especially at the joints of the segments. There must be. The segments that make up such a lining are:
What consists of reinforced concrete has been widely used conventionally. The joint portion of such a segment has, for example, a structure in which a joint box made of a steel material is fixed, and the joint boxes of the two segments to be joined are mutually fastened by bolts. Then, the segments connected in the circumferential direction are sequentially arranged and connected in the axial direction of the tunnel, but the positions where the joints in the circumferential direction are provided are different for each set of segments arranged in the axial direction. ing. As a result, the rigidity is substantially uniform in the circumferential direction.

However, the provision of the above-described joint structure in each segment requires a lot of cost for manufacturing the segment. Further, such a joint structure has a disadvantage that deformation during assembly is large and assembly accuracy is low. In addition, if the joint structure is simplified, the bending deformation of the joint will increase, and under conditions where the bending moment is greater than the axial force in the circumferential direction, such as in a shield tunnel in soft ground, the lining Will cause excessive deformation.

As a structure for overcoming such disadvantages, there is a structure in which prestress is introduced in a circumferential direction of a lining body. As shown in FIG. 10, the segment 111 of such a lining body has a substantially flat end face 111 at an end in the circumferential direction, and is assembled such that the end faces 112a of other adjacent segments 112 abut against each other. Can be These segments 111 and 112 are provided with ducts 113 in the circumferential direction, and when the segments are assembled in a ring shape,
A PC steel material 114 is inserted through the duct 113, and tension is introduced.

As shown in FIG. 11, the segment assembly 120 assembled in a ring shape is arranged so as to be continuous with the segment assembly 121 whose rear assembly has been completed, with its end faces abutting in the axial direction. A duct 122 is provided in each of these segments so as to be continuous with an adjacent segment in the axial direction, and a tensile force is introduced through a PC steel material. In this way, pre-stress is introduced in the circumferential and axial directions, and the assembled segments behave as a unitary and continuous member.

[0006]

However, in the conventional shield tunnel lining body, the segment assembly 120
End faces 120a, 12a of the
Since the surface 1a is flat, there is a possibility that a deviation may occur when assembling them in abutting manner. On the other hand, it is also performed to join the segment assemblies using a tenoned segment, but in this case, in order to obtain a tenon effect, a tenon and a concave portion fitted therein need a predetermined dimensional accuracy. There is a problem that high cost is required for manufacturing.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and can easily perform positioning when assembling a ring-shaped segment assembly with another ring-shaped assembly. It is an object of the present invention to provide a shield tunnel lining body capable of transmitting a shearing force between three-dimensional bodies and suppressing a manufacturing cost of a segment.

[0008]

In order to achieve the above object, a shield tunnel lining according to claim 1 is constructed by assembling a plurality of circumferentially divided segments made of reinforced concrete in a circumferential direction, and forming a plurality of segments in a circumferential direction. A PC steel material is inserted into a duct penetrating the segment in the direction, and a prestress is introduced in the circumferential direction by tensioning the PC steel material to form an integrated ring-shaped segment assembly in the axial direction. In a shield tunnel lining body configured by inserting a PC steel material into a duct that penetrates a segment and introducing a prestress in the axial direction by tensioning the PC steel material, and connecting a plurality of sets in the axial direction, An end face of the ring-shaped segment assembly, which is joined to another ring-shaped segment assembly, is provided with the other segment from the segment assembly. A plurality of protrusions are provided so as to protrude toward the segment assembly, and a plurality of recesses capable of accommodating the respective protrusions are provided on an end surface of the other segment assembly.

Accordingly, in order to assemble the other segment into the ring-shaped segment assembly, a plurality of projections provided on the end face of one segment assembly are provided on the end face of the other segment assembly. Butted so as to project into the recessed portion. As a result, the plurality of projections and recesses facilitate positioning during assembly. Further, the shearing force between the segment assemblies is transmitted by the plurality of protrusions and recesses. Furthermore, since the prestress is introduced in the axial direction of the segment assembly, even if the tenon effect is not obtained by using the tenoned segment, the partial joining key by the plurality of convex portions and concave portions is sufficient. Therefore, the manufacturing cost of the segment can be kept low.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a shield tunnel lining according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a shield tunnel lining body. FIG. 2 is a longitudinal sectional view of the shield tunnel lining body. This shield tunnel lining has a circular cross section and is divided into five segments 1 in the circumferential direction.
a, 1b, 1c, 1d, and 1e are assembled in a ring shape, and a large number of ring-shaped segment assemblies are arranged in the axial direction.

Of the above segments, four segments 1a, 1b, 1c and 1d have a center angle in the circumferential direction of about 84 °.
And the central angle of one segment 1e is 24 °
And these are closed circularly. The segment 1e having the central angle of about 24 ° is a final assembled segment, and as shown in FIG. 3, the dimension is reduced in the axial direction of the tunnel and the circumferential dimension is different at both ends.
This final assembly segment 1e is composed of other segments (segments having a central angle of about 84 °) 1a, 1b, 1c,
After the 1d has been erected, the segments 1 which are moved in the axial direction from the face side to drive the wedge into
a, 1d, and closes the five segments into a circle.

These segments are provided with ducts 2 buried in the circumferential direction. The duct 2 is open at the end face, and is arranged so as to be continuous in the circumferential direction when assembled in a ring shape. A fixing device 3 is embedded in the lowermost segment 1b, and the duct 2 is connected to the fixing device from both sides. As shown in FIG. 4, the fixing device 3 is made of cast iron, and has a shape in which two cylindrical portions into which a PC steel material is inserted are integrated so as to intersect obliquely. The duct can be connected to the holes 3a and 3b. In the segment 1b in which the fixing device 3 is embedded, two notches 5 are provided so that the end face 3c of the cylindrical portion of the fixing device 3 is exposed. Then, the PC steel material 6 is inserted into the duct 2 from one of the cutout portions 5 through the through-hole of the fixing device 3, makes a round in the ring-shaped segment, and passes through the other through-hole of the fixing device 3. Can be arranged so as to reach the other cutout.

The PC steel material 6 is provided with jacks at both ends and tensioned, or one of the PC steel materials 6 is attached to the fixing device by a wedge 4.
, And a jack is attached to the other side and tension is applied, so that circumferential prestress is introduced into the ring-shaped segment. The PC steel to which the tension is introduced is fixed to the fixing device by the wedge 4.

The segment assembly 30 assembled in a ring shape is arranged so as to be continuous with the segment assembly 40 whose rear assembly has been completed, with its end faces abutting in the axial direction. As shown in FIG. 5, a plurality of convex portions 32 project from the end surface 31 of the segment assembly 30 that abuts against the segment assembly 40 toward the segment assembly 40 at intervals in the circumferential direction. I have. Convex part 3
2 is formed in the shape of a truncated cone whose longitudinal cross section is a flat trapezoid. On the other hand, as shown in FIG. 6, a plurality of recesses 4 are provided on the end face 41 of the segment assembly 40, which face the segment assembly 30, at intervals in the circumferential direction.
2 are provided. The concave portion 42 is recessed in the same shape as the convex portion 32, and the size thereof is formed slightly larger than the convex portion 32. Then, as shown in FIG. 7, the segment assembly 30 and the segment assembly 40 are abutted such that each convex portion 32 projects into each of the concave portions 42 facing each other. Thus, the shearing force between the segment assembly 30 and the segment assembly 40 is transmitted by the plurality of convex portions 32 and concave portions 42.

Segments 1a, 1b having a central angle of 84 °
1c and 1d also have a PC in the axial direction of the shield tunnel.
A duct 8 for inserting a steel material is provided, and communicates with a duct provided in an axially adjacent segment. Duct 8 has segments 1a, 1
b, 1c, and 1d. As shown in FIG. 8, the same fixing device 9 as that arranged in the circumferential direction is embedded in two opposing segments 1b, 1d of the four segments 1a, 1b, 1c, 1d. Is joined to the fixing device 9, and the opposite end surface of the fixing device is exposed in a cutout portion 10 provided inside the segment.

The rear segments 11b and 11d, which are adjacent to the two segments 1b and 1d in which the fixing device 9 is provided in the axial duct 8 and the fixing device 9 is provided with no fixing device, are provided with the other two. A fixing device is embedded in a rear segment 11c axially adjacent to the two segments 1a and 1c. Therefore, every other fixing device is buried in the segments arranged in the axial direction of the shield tunnel, and the PC steel material in the axial direction is inserted through such fixing device 9 and the duct 8. Circumferential PC
When tension is introduced in the same manner as the steel material and the wedge is fixed to the fixing device 9 by wedges, two PC steel members of four PC steel members arranged in the axial direction are alternately formed into a ring-shaped segment assembly as shown in FIG. Will be established. The PC steel material that is fixed from both sides of the fixing tool 9 through the through holes is arranged in series in the axial direction of the shield tunnel, and is continuous in the axial direction by the integral fixing tool as shown in FIG. It can be transmitted.

Next, a process of assembling the shield tunnel lining segment by joining the above-described segments for the shield tunnel lining will be described. When the excavation at the face progresses and the shield machine advances, and at least one segment is formed between the face side end surface of the segment assembly and the rear end portion 20 of the shield machine, the five segments described above are used. Built
Assemble into a ring. Then, a PC steel material is inserted into the duct 2 which is communicated in the circumferential direction, and is fixed to the fixing device 3 in a state where a tension is applied to introduce a prestress in the circumferential direction.

As shown in FIG. 2, the segment assembly 30 assembled in a ring shape has an end face which is axially opposed to the segment assembly 40 which has been assembled rearward. At this time, as shown in FIG. 7, the projections of the segment assembly 30 are butted so as to project into the opposing recesses 42, respectively. Thereby, positioning can be easily performed.

The newly assembled segment assembly includes two segments in which the fixing device 9 in the axial direction is embedded and a cutout portion 10 is provided on the inner side. The PC steel material is inserted from the section 10 into the fixing tool 9 and into the duct 8 extending rearward. Then, it is pulled out to the inside of the lining from the fixing tool 19 buried in the rear segment separating a pair of adjacent segments.

This PC steel material is fixed at one end by a wedge to a fixing tool 19 embedded in a rear segment, and at the other end,
As shown in FIG. 2, the jack 14 is attached via the jack chair 13. The jack 14 applies a predetermined tension to the PC steel material, and in this state, the PC steel material is fixed to the fixing tool 19 by wedges. Thus, the new segment assembly is tied to the rear segment assembly by the tension of the two PC steels.

After the cutting with the face further proceeds, the next segment assembly is erected and the circumferential prestress is introduced, and then the PC steel material is moved backward from the axial fixing tool provided in this segment assembly. Is inserted into. The duct continuous with the fixing device is continuous with a duct provided so as to pass through the segment assembly in the axial direction, and is further drawn into the lining from the fixing device in the adjacent segment at the rear. Then, by introducing tension into the PC steel, the latest segment assembly is tied to the previous segment, and the previous segment is more strongly coupled to the rearwardly adjacent segment assembly. Such operations are sequentially repeated, and prestress is introduced substantially uniformly in the axial direction of the shield tunnel lining body.

In the above embodiment, the PC steel is arranged over three segments arranged in the axial direction.
Although the prestress is introduced so as to tighten them, as described above, a means of connecting the PC steel materials for each segment and tightening them may be adopted as described above.

[0023]

As described above, according to the present invention,
In a shield tunnel lining where prestress is introduced in the circumferential direction and the axial direction, positioning can be easily performed when assembling a ring-shaped segment assembly with another ring-shaped assembly, and working efficiency. Can be improved, the shear force between the segment assemblies can be transmitted, and the manufacturing cost of the segments can be suppressed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a shield tunnel lining according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the shield tunnel lining body shown in FIG.

FIG. 3 is a view showing a shape and a method of erection of a final assembly segment of the shield tunnel lining body shown in FIG. 1;

FIG. 4 is a front view and a longitudinal sectional view of a PC steel fixing device used in the shield tunnel lining body shown in FIG. 1;

FIG. 5 is a view of the segment assembly of the shield tunnel lining body shown in FIG. 2 as viewed from a wellhead side.

FIG. 6 is a view of the segment assembly of the shield tunnel lining body shown in FIG. 2 as viewed from the face side.

FIG. 7 is a sectional view taken along line AA in FIG. 2;

8 is a plan view of a segment constituting the shield tunnel lining body shown in FIG. 1, in which a fixing device in a circumferential direction and an axial direction is embedded.

9 is a diagram showing the position of a PC steel material and its fixing tool arranged in the axial direction of the shield tunnel lining body shown in FIG. 1 on a cross section and a developed view of the lining body.

FIG. 10 is a schematic cross-sectional view showing an example of a joining portion between segments of a conventionally known shield tunnel lining body.

FIG. 11 is a schematic sectional view showing an example of a conventionally known shield tunnel lining body.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 segment 2 duct 6 PC steel 8 duct 11 rear segment 30 segment assembly 31 end face 32 convex section 40 rear segment assembly 41 end face 42 concave section

Claims (1)

[Claims] 1. A segment made of a plurality of reinforced concrete divided in a circumferential direction is assembled in a circumferential direction, a PC steel material is inserted into a duct penetrating the segment in the circumferential direction, and the PC steel material is tensioned by being tensioned. The ring-shaped segment assembly integrated by introducing prestress in the direction is inserted into a duct penetrating the segment in the axial direction of the PC steel material, and the PC steel material is tensioned by tensioning the PC steel material. In a shield tunnel lining constituted by connecting a plurality of sets in the axial direction by introducing stress, an end face of the ring-shaped segment assembly which is joined to another ring-shaped segment assembly is provided with the segment. A plurality of projections protruding from the assembly toward the other segment assembly; an end of the other segment assembly; The shield tunnel lining body, characterized in that said providing a plurality of recesses which can accommodate the respective protruding portions.