JP2574988B2 - Reinforcement structure of shield segment joint end - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforcing structure for an end of a shield segment joint.

[0002]

2. Description of the Related Art In a segment, adjacent segments are connected to each other by joint bolts. The periphery of the joint bolt is subjected to the tensile force of the bolt at a plain concrete portion between the washer of the bolt and the end face of the segment. If the load received is large, cracks occur in the plain concrete portion due to the pressure transmitted from the washer, and ultimately break.

On the other hand, the present applicant has filed a Japanese Patent Application No. Hei.
No. 29 (see Japanese Patent Application Laid-Open No. Hei 7-11896) proposes a reinforcing structure shown in FIGS.

[0004] In FIG. 4 and FIG.
It is arranged in two upper and lower stages in parallel with 2, 23, and the segment 1B,
The circumferential tensile strength of 1B is reinforced.

[0006] As shown in FIG. 6, joint bolts 22 and 23 are surrounded by a V-shaped shear reinforcing bar 21 from the inner peripheral side.
Strengthening in the shear direction. However, according to the prior art, both the tensile strength in the circumferential direction and the strength in the shear direction could not be satisfied.

[0006]

Accordingly, the present invention provides
It is an object of the present invention to provide a reinforcing structure at the end of a shield segment joint that can improve the tensile strength and the shear strength at the circumferential ends of adjacent segments.

[0007]

According to the present invention, there is provided a shield segment joint end reinforcing structure in which adjacent circumferential ends of adjacent segments are tightened by joint bolts using a joint box. Reinforcing reinforcing beams extending parallel to the end surface are arranged between the box and the circumferential end surface.

It is preferable that the reinforcing reinforcing beam is composed of a plurality of rectangular reinforcing bars arranged in the circumferential direction of the segment and a plurality of connecting bars connecting the plurality of reinforcing frames in the circumferential direction. .

[0009]

In the reinforcing structure of the end of the shield segment joint constructed as described above, the conventional segment which receives the force from the joint bolt of the segment has a plain concrete portion at the circumferential end of the adjacent segment. However, in the present invention, the tensile strength and the shear strength are enhanced by the reinforcing steel beams, and thus the occurrence of cracks is suppressed.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a conventional plain concrete portion 4 between a joint box 3 and an end face 2 on the side of a segment 1A adjacent to the segment 1 in the circumferential direction is denoted by a reference numeral which is parallel to the end face 2. A reinforcing steel beam indicated by 10 is provided. The two segments 1, 1A are provided with a plurality of joint bolts 6, nuts 7, and washers 8 inserted into joint bolt holes 5, 5A communicating with the joint boxes 3, 3A (FIG. 3).
Are tied up.

In FIG. 2 and FIG.
Is welded inside a plurality of (seven in the illustrated example) rectangular reinforcing bar frames 11 arranged in the circumferential direction and the reinforcing bar frames 11 connecting the plurality of reinforcing bar frames 11 in the circumferential direction. And eight (eight in the illustrated example) connecting bars 12. The joint bolt holes 5 are provided between the reinforcing bar frames 11 and between the connecting bars 12.

Next, the operation will be described.

Since the reinforcing steel beam 10 is disposed in the conventional plain concrete portion 4 between the end face 2 of the segment 1 and the joint box 3, the tensile strength of the joint bolt 6 with respect to the tensile force is equal to the reinforcing steel. Horizontal portion 11a of frame 11 and connecting bar 1
2 and is strengthened.

The shear strength of the segments 1 and 1A with respect to the shear force is determined by the vertical portion 11b of the reinforcing bar frame 11 and the connecting bars 12a.
And will be strengthened.

[0016]

According to the present invention, as described above, the end to which a force is applied by the joint bolt of the segment is reinforced to improve the strength and suppress the occurrence of cracks.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a front view of FIG. 1;

FIG. 3 is a side view of FIG. 1;

FIG. 4 is a side view showing an example of a reinforcing structure proposed by the present applicant.

FIG. 5 is a top view of FIG. 4;

FIG. 6 is a front view showing another example of the reinforcing structure proposed by the present applicant.

[Explanation of symbols]

 1, 1A, 1B ... segment 2 ... end face 3 ... joint box 4 ... unreinforced concrete part 5, 5A ... joint bolt hole 6, 22, 23 ... joint bolt 7 ... · Nut 8 · · · Washer 10 · · · Reinforced rebar beam 11 · · · Reinforcement frame 12 · · · Reinforcing bar 20 · · · U-shaped tensile reinforcing bar 21 · · · V-shaped shear reinforcing bar

Claims (1)

(57) [Claims] 1. A shield segment joint end reinforcing structure in which adjacent circumferential ends of adjacent segments are fastened by a joint bolt using a joint box, between a joint box of the segment and a circumferential end surface. A reinforcing structure at an end of a shield segment joint, wherein a reinforcing reinforcing beam extending parallel to the end face is provided.