JPH074187A - Joint structure of lining segment - Google Patents

Abstract

PURPOSE:To provide the capability of coping with internal pressure by forming a shear resistance section such as ribs staggered along the peripheral direction of lining, on the ring joint surface between segments, and filling the gap of the jointed surface with a filler for jointing the segments to each other. CONSTITUTION:In space inside the skin plate 20 of a shield machine, synthetic segments 1A are held with an erector and supported on a mobile timbering device 21. Concrete 22 is placed in the concrete filling space 6 of a steel hull from a concrete filling port. Then, the coupling sections 12 and 13 of the segments 1A joined together via a seal member 25, and filling space 26 formed out of the filling recesses of both segments 1A is filled with a filler 27. While a shield machine is being propelled with a propulsion jack 23, a back-filling material 24 is fed through a back-filling port 16. According to this construction, segment rings, particularly when subjected to internal pressure, can effectively cooperate with each other for resisting axial tension and cross sectional shear.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure for a segment used for lining a shield tunnel, a pit, etc., to which internal pressure acts.

[0002]

2. Description of the Related Art In a conventional shield tunnel, as shown in FIG. 12, a segment is designed mainly by an external pressure from the outside of the lining, and the segment structure and the joint method are determined based on the result. Therefore, the segment is mainly subjected to a compressive force in the axial direction (X-axis direction in the figure, that is, the tunnel circumferential direction), and changes in tunneling load due to increase in earth pressure and water pressure in the tunnel depth direction. Thus, a bending force (a force bending the X axis) and a shearing force act. As a result, the segment and its joint are combined with a large compressive force and a bending force, and generally a compressive stress is generated in the entire cross section.

On the other hand, when designing a segment such as an underground river where an internal pressure (internal pressure due to the stored water in the lining) acts in addition to an external pressure, the above-mentioned function is required for the external pressure action. In addition, when the external pressure and the internal pressure act at the same time, the stress generated in the segment and the joint is significantly different from that when only the external pressure acts, and therefore a structure corresponding to that is required.

That is, when the internal pressure acts, a tensile force is generated in the X-axis direction, which is combined with the compressive force generated by the action of the external pressure to reduce the axial compressive stress. However, depending on the magnitude of the internal pressure, the segment and the joint may be jointed. A tensile force is generated at.
Further, when the internal and external pressures are simultaneously applied, the axial compressive force is reduced in the segment cross-section, so that stress excellent in bending action is generated. Therefore, the segments and joints need a structure that is strong against bending and pulling.

From the above viewpoint, the conventional main segment and its joint structure will be examined as follows.

(1) RC segment (general type) Looking at the segment body, the RC segment originally has a structure effective against compressive force by taking advantage of the characteristics of concrete. Even if a bending load acts, the axial compressive force In the combined state, the stress distribution in the cross section is used in the range of compression. Therefore, it is not suitable for a structure in which the internal pressure acts and the combined tensile stress of bending and bending is large. As for the joint structure, as shown in FIG. 13, it is generally a structure corresponding to forward bending by bolt connection. Therefore, it is structurally difficult to deal with negative bending force and axial tension due to internal pressure. In addition, the tensile force and the shearing force act on the bolt at the same time, which is unsuitable for the structure.

(2) Segments with RC mortises One segmented surface of the segment body is provided with a long recessed ridge along its surface, and the other segmented surface is provided with a long projection boss along the surface thereof. It has a structure in which the groove and the convex groove are fitted as they are to form a joint. However, although the joint structure is simple, there is a drawback that high precision of processing is required, it is impossible to assemble unless there is a margin of construction, and when the internal pressure acts, the segments open apart in the circumferential direction of the lining. is there.

(3) Steel segment and tag tile segment Since the segment bodies are made of steel and cast iron, respectively, they can handle tensile force. However, the joint is RC
Since it is bolted like the segments, it is structurally inappropriate for internal pressure.

(4) Synthetic segment (a steel shell filled with concrete and integrated with ribs and dowels provided in the steel shell) The segment body is subjected to both positive bending and negative bending. However, it can handle large loads, and can sufficiently handle shearing, compression and axial tension with both steel and concrete. However, even if the segment body itself is excellent in this way, as for its joint, it is disclosed in JP-A-4-106.
Since it is bolted as described in Japanese Patent Publication No. 299, it is structurally difficult to cope with negative bending force and axial tension (tensile force in the tunnel circumferential direction) due to internal pressure. on the other hand,
As a joint structure for a composite segment, JP-A-4-3
As described in Japanese Laid-Open Patent Publication No. 30197, it is proposed that a flange portion on the outer surface of a steel shell is provided with a joint portion by concave and convex fitting. According to this, not only axial compression and positive bending force but also negative bending force can be dealt with, but axial tension due to internal pressure is difficult to deal with.

All of the above-mentioned conventional examples are designed based on the basic idea of dealing with external pressure, and the joint has a structure that can be easily assembled even when external pressure acts. However, when considering the internal pressure due to the stored water, the internal pressure acts after the lining is completed. Therefore, in order to deal with the internal pressure, a structure corresponding to the internal pressure after completion of the lining is sufficient.

[0011]

Therefore, in view of the above points, an object of the present invention is not only for positive bending / negative bending / shearing / axial compression but also for axial tensioning even when internal pressure acts on the lining. It is to provide a joint structure that can sufficiently cope with it.

[0012]

In the joint structure according to the present invention, a shear resistance portion that is staggered in the circumferential direction of the lining is provided on the joint surface between the rings of the segments, and the filler is provided in the gap between the shear resistance portions of the segments. To join the segment rings. When a filling recess is formed on the joint surface between the rings of the segment body like a synthetic segment, ribs are provided in the filling recess, and the rib serves as a shearing resistance portion in the filling recess. It is embedded in the filling material filled in.

[0013]

According to the present invention, as a form after completion of the lining, the filler is filled between the segment rings, and the shear resistance portions of the segments between the segment rings are staggered in the circumferential direction of the lining so that the filler is filled. It will be sandwiched. Therefore, the friction between the segments, the adhesive force between the filler and the segment body and the shear resistance portion, the compression rigidity of the filler,
With respect to the lining circumferential shear rigidity of the filler and the shear resistance part, it resists external and internal pressures, especially against axial tensile force (circumferential lining tensile force) and cross-section shear when internal pressure acts. , Segment rings are mutually assisted and effectively counter each other.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first example of a composite segment used in a shield tunnel. The composite segment 1A is a rectangular steel frame 2 which is entirely rectangular in the circumferential direction of the tunnel and is closed on both sides with curved steel plates 3 and 4 (inside and outside of the tunnel) to form a steel shell 5. It is configured by filling the concrete filling space 6 by 5 with concrete.

The steel frame 2 is made of, for example, an H-shaped or I-shaped steel material, and has inner and outer flange portions 7 and 8 and a web 9 on its outer peripheral surface.
The groove-shaped filling concave portion 10 is formed by, and a large number of shear resistance ribs 11 made of steel pieces are formed.
The flanges 7 and 8 are fixedly attached to the web 9 at intervals along the outer peripheral edges of the flanges 7 and 8 as shown in FIG. In the illustrated example, the rib 11 has a size such that the tip of the rib 11 projects from the filling recess 10.

The steel plate 3 on the inner side has a concrete inlet 1
4. The web 9 of the steel frame 2 is provided with a plurality of joint filling ports 15, and a pipe backfill inlet 16 is provided so as to penetrate the inner and outer steel plates 3 and 4. Further, inside the steel frame 2, a plurality of thrust transmission members 17 in the tunnel axial direction and a plurality of reinforcing bars 18 in the tunnel circumferential direction are arranged. In order to improve the connection with the concrete filled in the concrete filling space 6, a large number of dowels or studs 19 are fixed to both or one of the inner and outer steel plates 3 and 4. The dowel or stud 19 may be omitted.

In the assembly of the composite segment 1A of the first example, as shown in FIG. 4, for example, in the skin plate 20 of the shield machine, the composite segment 1A is grasped and positioned by an erector in the same manner as in the conventional case, and the existing structure is used. The composite segment 1A is supported by a self-propelled support device 21 from the inside of the shield machine so as to form a staggered set, and concrete 22 is filled into the concrete filling space 6 of the steel shell 5 from the concrete injection port 14 and the composite segment 1A are joined to each other as follows, and the backfill material 24 is injected through the backfill injection port 16 while the shield jacking machine is propelled by the propulsion jack 23.

2 and 3 show a joining example in which two composite segments 1A adjacent in the tunnel axial direction are joined by the joint structure according to the present invention. In this case, a so-called ring joint is used. In the figure, the fitting portions 12 and 13 of the synthetic segments 1A are fitted to each other via the sealing material 25, and the filling gap 26 formed by the filling recesses 10 of both synthetic segments 1A is filled with concrete, mortar, or the like. The material 27 is filled. In the illustrated example, this filling is made up of the concrete 22 poured into the concrete filling space 6 of the steel shell 5.
Can also be injected into the filling gap 26 through the joint filling port 15. For example, the inner steel plate 3
By separately providing a joint filler injection port communicating with the filling recess 10, it is possible to fill the filling gap 26 with mortar separately from the concrete filling the concrete filling space 6. The ribs and ribs of the two composite segments 1A formed in a zigzag pattern are staggered in the circumferential direction of the tunnel, and the filler 27 is sandwiched between them to partially fill the filler 2
Buried in 7.

According to such a joint structure, the friction between the steel frames 2 and the fitting between the fitting portions 12 and 13, the filling material 27 and the steel frame 2 are prevented even when the bending and the pulling due to the external pressure and the internal pressure occur.
And the adhesive force with the rib 11, and the compression rigidity of the filler 27,
It can be effectively countered by the shear rigidity of the filler 27 and the rib 11 in the circumferential direction of the tunnel. The same is true between the synthetic segments 1A adjacent to each other in the tunnel circumferential direction (so-called segment joint). FIG. 5 shows a stress transmission pattern between adjacent segments with respect to an axial tensile force and a bending moment. It should be noted that the fitting rigidity is increased if the fitting portions 12 and 13 are provided, but this is not always necessary in the present invention. Further, depending on the magnitude of the acting force, it is possible to adopt a structure in which the ribs do not overlap each other.

The synthetic segment 1B of the second example shown in FIG.
Is an inner steel plate 3 in the composite segment 1A of the first example.
Is omitted and the inner surface of the steel shell 5 is opened, and its joint structure is the same as in the first example. On the contrary,
The joint structure according to the present invention can be similarly applied to a synthetic segment in which the outer steel plate 4 is omitted and the outer surface of the steel shell 5 is opened.

A composite segment in which both the inner and outer surfaces of the steel shell 5 are closed with steel plates, a composite segment in which the inner steel plate is omitted and the inner surface of the steel shell 5 is opened, and conversely the steel plate in which the outer steel plates are omitted is omitted. In any case of the synthetic segment in which the outer surface of the shell 5 is opened, the protruding portion of the rib 11 for shear resistance is not one portion in the central portion of the recess 10 for filling as described above, but as shown in FIG. There can be two locations close to both flanges 7 and 8. In this case, it is preferable to form a gap 11a for venting air at a corner portion between the rib 11 and the flanges 7 and 8.

8 and 9 show examples applied to the tag tile segment, respectively. The tag tile segment 1D shown in FIG. 8 is box-shaped, and has a filling recess 32 formed on the outer surface of the peripheral wall 29 by the flanges 30 and 31 that are divided inward and outward of the tunnel.
The flanges 30 and 31 are provided with fitting portions 30a and 31a, which are symmetrical step portions, on the edges of the flanges 30 and 31, and a large number of shear resistance ribs 33 are provided along the filling recess 32 at intervals. It is the one protruding from. The tag tile segment 1E of FIG. 9 is a corrugated type, and the outer surface of the peripheral wall 29 and the flanges 30 and 31 have the same structure as in FIG. 8. The ring joint structure of these two types of tag tile segments 1D and 1E is as described above. It becomes the same as the case of the composite segment.

10 and 11 show examples applied to the RC segment. A plurality of deep recesses 34 for shear resistance are provided at intervals in the tunnel circumferential direction on one surface of the ring-to-ring joint surfaces on both sides of the RC segment 1F, and the other surface corresponds to the deep recesses 34. Shear resistance projection 3
5 is provided. The projection 35 is smaller than the deep recess 34 so that a gap 36 can be formed when the projection 35 is inserted into the deep recess 34. A shallow recess 37 is formed between the deep recess 34 and the deep recess 34. In joining the segment rings, a filler 39 such as mortar is filled with a seal member 38 at a place where there is no recess on the joint surface, and the deep recesses 34 and the protrusions 35 form a tunnel circumferential direction. And a structure in which the filler 39 is sandwiched and fitted in both directions of the inside and outside of the tunnel.

[0024]

According to the joint structure of the present invention, as a form after completion of the lining, the filling material is filled between the segment rings, and the shear resistance portions of the segments are dissimilar in the circumferential direction of the lining between the segment rings. Since the filler is sandwiched between them, in addition to the friction between the segments, the adhesive force between the filler and the segment body and the shear resistance portion, and the compressive rigidity of the filler, the lining of the filler and the shear resistance portion is performed. Shear stiffness in the circumferential direction also opposes stress. Therefore, it is possible to effectively counter axial tensile force (circumferential tensile force of lining) and cross-section shear when internal pressure acts, and it is suitable for lining such as underground rivers and water storage facilities where internal pressure acts. is there.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a first example of a composite segment to which a joint structure according to the present invention is applied.

FIG. 2 is a vertical sectional view of a joint structure according to the present invention applied to the composite segment.

FIG. 3 is a horizontal sectional view of the same.

FIG. 4 is a cross-sectional view showing an example of assembling and installing the composite segment.

FIG. 5 is a diagram showing a stress transmission pattern between adjacent segments.

FIG. 6 is a sectional view of a second example of a composite segment.

FIG. 7 is a cross-sectional view of an essential part of a modified example of a joint portion.

FIG. 8 is a cross-sectional view of a box-type tag tile segment to which the joint structure of the present invention is applied.

FIG. 9 is a cross-sectional view of a corrugated tag tile segment.

FIG. 10 is a sectional view of a joint structure according to the present invention applied to an RC segment.

FIG. 11 is a front view of the above.

FIG. 12 is a model diagram of external pressure acting on a shield tunnel.

FIG. 13 is a cross-sectional view showing a conventional bolt type joint structure.

[Explanation of symbols]

 1A / 1B / 1C Composite segment 1D / 1E Tag tile segment 1F RC segment 2 Steel frame 5 Steel shell 10 Filling recess 11 Rib 26 Filling gap

Claims (4)

[Claims] 1. A shear resistance portion that staggers in the circumferential direction of the lining is provided on the joint surface between the rings of the segments, and a filler is filled in the gap between the shear resistance portions of the segments to join the segment rings. Characteristic lining segment joint structure. 2. The shear resistance portion is a rib protruding from a filling concave portion of the inter-ring joint surface of the segment, and the rib is embedded with a filling material filled in the filling concave portion. The joint structure of the lining segment according to claim 1. 3. A joint for a lining segment according to claim 2, wherein each segment has a steel shell that is filled with concrete, and the filling recess and the rib are provided on an outer surface of the steel shell. Construction. 4. The shear resistance portion is a joint concave portion and a joint convex portion provided on the inter-ring joint surface of the segment,
The joint structure for a lining segment according to claim 1, wherein the recesses and the protrusions are fitted with a filler to join the segment rings.