JPH06280496A - Structure for coupling ring to segment in shield method - Google Patents

Abstract

PURPOSE:To obtain firm coupling structure by forming a mortice in one alignment face of a concrete segment, forming a tenon in the other alignment face, and forming a motice and a tenon fitted thereto in a shear force transferring member loading section to bury reinforcing bars. CONSTITUTION:Width-directional side both ends of a segment main body 21 are lining axial side alignment faces 22c and 22d as same as alignment faces 22a and 22b of lengthwise both ends, and a recessed groove 23 for sealant connected to a recessed groove 23 is formed. After that, shorter shear force transferring mortices 25, 25,... are formed in the alignment face 22c, and longer mortices 26 and 26 are formed in a position from the central part to both end parts, and shear force transferring tenons 27, 27,... and longer tenons 28 and 28 are formed together as a unit in the other side alignment face 22d. Then, a large number of main bars 29 and distributing bars 30 are inserted in the main body 21 lengthways, and ring-shaped reinforcing bars 32 and 32 are inserted around the mortice 25. A shear force transferring member 33 is made to lie between shear force transferring mortice and tenon 25 and 27, and the alignment faces 22c and 22d are connected to each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connecting structure between lining axial sides of segments, that is, segment rings in a shield construction method using so-called mortise-concrete concrete segments.

[0002]

2. Description of the Related Art Generally, in the shield construction method, every time the excavator is dug a certain length, the segments 1, 1 in the shape of an arc plate are assembled in a ring shape at the rear portion as shown in FIG. Are sequentially extended to form a cylindrical lining 3, and in recent years, as the segment 1, as shown in FIG. 8, the lining axial end of the segment 1, that is, the segment ring joint side A mortise-reinforced concrete segment (hereinafter simply referred to as a mortise segment) in which one end is provided with a convex tenon 4 having a trapezoidal cross section and the other is provided with a concave tenon 5 into which the convex tenon 4 is fitted Being developed. This is because a fitting box used in a standard type concrete segment, by transmitting the shearing force generated between the rings by fitting the concavo-convex mortises 5 and 4 between the lining segment rings 2 and 2, It was developed for the purpose of eliminating the need for bolted nut fittings.

Further, when fitting the concave and convex tenons 5 and 4, in order to prevent the concrete surface from directly contacting and transmitting the shearing force, as shown in FIG. A plate-shaped shear force transmitting material 8 having a property is partially applied, and the concave and convex tenons 5 and 4 are fitted to each other via the shear force transmitting material 8.

[0004]

For the purpose of confirming the shear resistance performance and the load-carrying performance of the entire lining of such a joint between rings of the conventional tenon segment, the present inventor has shown in FIG. Using flat plate-shaped test pieces 6 and 7, the convex tenon 4 and the concave tenon 5 were provided and fitted to each other, and a shear test was performed by applying a load as shown by an arrow. As a result, it was found that the jaw 9 inside the concave tenon was broken at an angle of about 45 ° as shown in FIG.

In this shear test, the desired shear resistance performance was initially satisfied, but the jaw portion at the stage where the maximum shear resistance was exhibited, that is, when the segment ring joint was broken, The stress level of the reinforcing bar installed for the purpose of reinforcement is about 50% of the stress level corresponding to the yield point of the reinforcing bar used as the reinforcing bar, and the fracture state is concrete of the inner jaw of the concave tenon 5. The concrete was in a state of shear failure, in which the attachment between the and reinforcing bars was cut.

In order to confirm the load-carrying performance of the lining connected by the segment ring joints of the same structure, three segment rings 2, 2 and 2 are overlapped as shown in FIG. No, but the central segment ring 2 with the required axial and circumferential loads
Through the beams 10 and 10 and the steel rods 11 and 11.
As a result of carrying out a load test in which 2 and 12 are applied, at the maximum load, the fracture of the joint between rings was confirmed before the segment body, and the fracture property was also the shear test result of the inter-ring joint described above. Was similar to.

From the results of such a shear test of the inter-ring joint portion, the present inventor has found that in order to improve the load bearing performance of the ring having the inter-ring joint portion structure by fitting the concave and convex tenons, the concave tenon side We have found that it is necessary to improve the shear resistance of the jaws, and it is necessary to reinforce the jaws on the concave tenon side, which is different from the conventional method. The purpose of the present invention is to provide a connection structure between segment rings provided with a joint portion.

[0008]

The feature of the present invention for achieving the above object is to provide a concave tenon on one of the joining surfaces of concrete segments to be joined to each other on the axial side of the lining and to form a convex tenon on the other side. In the connecting structure between the segment rings in the shield construction method, in which the two concavo-convex tenons are fitted to each other, and the shearing force transmitting material is partially interposed between the concavo-convex tenon, another portion is attached to the shearing force transmitting material mounting portion. A concave tenon for shearing force transmission separate from the portion and a convex tenon for shearing force fitting to this are provided,
A ring-shaped reinforcing bar is embedded around the concave tenon, and a shearing force transmitting material is interposed between the two concavo-convex tenon for transmitting shearing force to fit each other.

[0009]

In the connection structure between segment rings of the present invention, the shearing force between the segment rings generated by the external force against the lining is countered by the fitting structure of the uneven tenon for shearing force transmission via the shearing force transmitting material. However, since the circumference of the concave tenon is reinforced by the reinforcing bar on the ring, the shear resistance performance is higher than that of the concave tenons of other parts, so the jaw that bears the shearing force has higher strength and the lining The overall shear resistance is high.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS.

1 to 4 show an example of a segment used in the present invention. In this segment, both ends in the length direction of the arc-shaped plate-shaped main body portion 21 are joint surfaces 22a and 22b on the circumferential side of the segment ring, and a seal material is formed on the outer surface side of the segment on both joint surfaces. A groove 23 is formed. By joining a plurality of segments in the joining surfaces 22a and 22b and connecting the segments with connecting bolts (not shown) passing through bolt holes 24, a segment ring similar to the conventional one shown in FIG. 6 is formed. It has become so.

Both end surfaces in the width direction of the main body portion 21 are lining axial side joint surfaces 22c and 22d, and the joint surface is also provided with a groove 23 for a sealing material which is connected to the above-mentioned groove 23. Has been done.

Short joint shearing mortices 25, 25 ... Are independently formed at both ends and the central portion of the joint surface 22c on both sides at substantially the central position in the segment thickness direction. In addition, one long mortise 2 is provided at each position from the center to both ends.
6, 26 are formed. The joining surface 22d on the other side is integrally formed with a protruding tenon 27, 27 for transmitting shearing force and a long convex tenon 28, 28 in a shape corresponding to the concave tenons 25, 26 at positions corresponding to each other. Has been done.

Further, as shown in FIGS. 4 and 5, a large number of main reinforcing bars 29 and power distributing bars 30 surrounding the main reinforcing bars 29 are inserted in the main body portion 21 as described above. Ring-shaped reinforcing bars 32, 32 are inserted around the recessed tenon.

Thus, the concave tenon 25, 26 and the convex tenon 2
The segment lining is formed by joining the joining surfaces 22c and 22d provided with 7, 28 to each other and extending the segment ring in the lining axial direction. When joining 22d, as shown in FIG. 2 and FIG.
The shearing force transmitting member 33 made of an elastic material is interposed between the members 27, and they are joined to each other, and are connected by a connecting bolt (not shown) which is passed through the connecting bolt hole 24.

[0016]

As described above, in the segment ring connecting structure of the present invention, the joint end face of the segment is provided with the uneven tenon for transmitting the inter-segment shearing force independent of the other part, and the periphery of the concave tenon is provided. By strengthening with the ring-shaped reinforcing bar, the shear force transmission material made of elastic material is attached and the portion where the shear force is concentrated becomes strong, and the shear resistance of the jaw part of the concave tenon becomes large, and the segment covering The shear resistance of the entire work can be increased.

[Brief description of drawings]

FIG. 1 is a plan view of an example of a segment used in the present invention.

FIG. 2 is a front view of the above.

FIG. 3 is a rear view of the above.

FIG. 4 is an enlarged front view of the above-mentioned concave tenon.

FIG. 5 is a cross-sectional view of a state in which the above segments are joined in the lining axial direction.

FIG. 6 is a perspective view of a lining by a segment of a conventional shield construction method.

FIG. 7 is a perspective view of the same segment.

FIG. 8 is a cross-sectional view of the above segment ring joint part.

FIG. 9 is a front view showing a shear test state using a flat plate-shaped test piece.

FIG. 10 is a partial perspective view showing the same shear fracture state.

FIG. 11 is a side view showing a ring loading test state in which segment rings are overlapped.

[Explanation of symbols]

 1 segment 2 segment ring 3 lining 4 convex mortise 5 concave mortise 6,7 test piece 8 shear force transmitting material 9 jaw 21 segment main body 22a, 22b, 22c, 22c, 22d joint surface 23 concave groove 24 bolt hole 25 concave mortise 26 Long concave mortise 27 Convex mortise 28 Long convex mortise 29 Main reinforcing bar 30 Distribution bar 32 Reinforcing bar 33 Shear force transmitting material

Claims (1)

[Claims] 1. A concave tenon is provided on one of the joint surfaces of concrete segments to be joined to each other on the lining axial direction side, and a convex tenon is provided on the other, and both concave and convex tenons are fitted to each other, and the concave and convex tenon spaces are provided. In the connecting structure between the segment rings in the shield construction method in which the shear force transmitting material is partially interposed in the above, in the shear force transmitting material mounting portion, an individual shear tenon for separating the shear force and this Providing a fitting tenon for transmitting shearing force, embedding a ring-shaped reinforcing bar around the concave tenon, and inserting a shearing force transmitting material between the two concavo-convex tenons for transmitting shearing force and fitting them together. The connecting structure between segment rings in the shield method, which is a feature.