JPH1082279A - Flexible joint for earthquake resistance of shield segment and its construction method - Google Patents

Abstract

(57) [Problem] To provide an earthquake-resistant structure that can easily and inexpensively follow shear deformation without using expensive flexible segments having a special structure. A rubber gasket (8) is disposed between ductile segments (2a, 2b), and a segment fastening bolt (9) penetrating the rubber gasket (8) is inserted into a slightly larger bolt hole of the ductile segments (2a, 2b) to provide an elastic washer (10). And a large steel washer 11 was interposed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible joint for earthquake-resistant shield segments and a method for constructing the same.

[0002]

2. Description of the Related Art As is well known, a shield tunnel is constructed by assembling segments into a ring shape, and further connecting the segment rings sequentially in the tunnel length direction to form a tunnel. There are both segments made of concrete and segments made of steel, and in each case, joining is performed by fastening bolts and nuts.

[0003] A seismic structure has been used by making the shaft and tunnel junctions of the shield tunnel flexible.

[0004] A flexible segment having a flexible structure is used as a general flexible joint for earthquake proofing to form such an earthquake-resistant structure.

[0005]

Such a flexible segment is very expensive as a special structure. Also,
Elastic washers and rubber gaskets may be used continuously in multiple rings in general tunnels mainly as a countermeasure for settlement and uplift.However, the use of these elastic washers and rubber gaskets for earthquake-resistant structures has the following problems. .

Although a high water pressure is required to reliably stop water with a rubber gasket, there is a possibility that the rubber gasket is pushed inward by external water pressure.

[0007] By sandwiching the rubber gasket between the rings, the axial displacement can be absorbed, but the shear displacement cannot be absorbed beyond the clearance between the bolt and the bolt hole, and excessive stress concentrates on the joint.

An object of the present invention is to solve the above-mentioned disadvantages of the prior art, and to provide a shield segment which can easily and inexpensively and follow shear deformation without using a flexible segment having an expensive special structure. An object of the present invention is to provide a flexible joint for earthquake resistance and a method of constructing the same.

There is a possibility that the rubber gasket will be crushed by the thrust of the shield jack during the construction of the shield.

[0010]

According to the present invention, in order to achieve the above object, as a seismic flexible joint for a shield segment, first, a rubber gasket is disposed between ductile segments and penetrated through the rubber gasket. The elastic bolt washer was inserted through the bolt hole of the ductile segment with the segment fastening bolt slightly enlarged,
Third, the seam of the rubber gasket is cut obliquely and wrapped and crimped. Third, the rubber gasket is attached to the segment with an adhesive. Fourth, a cover plate is formed on the outer and inner surfaces of the ring joint surface of the segment. The main point is to install ethylene foam in the gap between the cover plate and the gasket.

As a method of constructing the flexible joint for earthquake resistance of the shield segment, a rubber gasket is disposed between the ductile segments, and the segments are assembled by interposing an elastic washer on a segment fastening bolt penetrating the rubber gasket, and temporarily attaching the segments. The gist of the invention is to use a fixing member as a thrust transmitting member and frictionally join the longitudinal ribs of the ductile segments on both sides of the rubber gasket with bolts.

According to the first aspect of the present invention, the compression member is a rubber gasket and the tension member is a bolt + elastic washer, so that the compression stiffness, the tensile stiffness and the bending stiffness of the tunnel are reduced, and the flexible structure is provided. It can be. Also,
RC segments on both sides of rubber gasket that concentrate on stress
By changing the segment to a ductile segment having high rigidity, and further increasing the bolt hole and installing an elastic washer, it becomes possible to follow the shear deformation.

According to the second aspect of the present invention, in addition to the above-described operation, the seam of the rubber gasket is provided on the top 1 having a low water pressure.
It is possible to improve the pressure-bonding property and secure the water-stopping property by oblique cutting.

According to the third aspect of the present invention, the rubber gasket is attached and compressed to a predetermined thickness, so that the resistance against the escape by the external pressure can be increased.

According to the fourth aspect of the present invention, it is possible to prevent the backfill material or concrete from flowing into the space between the rings during backfilling and during secondary lining.

According to the fifth aspect of the present invention, the provision of the temporary fixing member as the thrust transmitting member prevents the rubber gasket from being compressed by the propulsion jack at the time of excavating the shield, so that the predetermined deformation performance cannot be secured. . In addition, by using the temporary fixing material as a spacer, the rubber gasket can have a substantially uniform initial compression amount.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a longitudinal sectional side view of an essential part showing an embodiment of an earthquake-resistant flexible joint of a shield segment according to the present invention, FIG. 2 is a longitudinal sectional side view of the whole of the same, and FIG. 4 to 9 are longitudinal side views showing each step of the method of the present invention, in which 1 is RC (reinforced concrete).
The segments 2a and 2b are steel ductile segments, and 3 is a skin plate of the shield machine.

As shown in FIG. 4, a ductile segment 2 a on the wellhead side is assembled to be connected to the RC segment 1, and a shield machine is dug by a shield jack as shown in FIG. From the location to the location of the ductile segment 2a.

FIGS. 12 and 13 show the outer cover plate 5 used in the present invention, and FIGS. 14 and 15 show the inner cover plate 6.
In each case, the ribs 7 are formed on the inner side with an angle material, and the outer cover plate 5 is coated with a tar epoxy.

The outer cover plate 5 is attached, and FIG.
A rubber gasket 8 made of a natural rubber material having a bolt hole 8a penetrating in the front-rear direction as shown in FIG.

Although not shown, the rubber gasket 8 is attached to the joint surface of the ductile segment 2a with an adhesive, and the joint is cut obliquely and wrapped.

As shown in FIG. 1, a steel washer 11 and an elastic washer 10 made of a natural rubber material as shown in FIG. 11 are interposed in the bolt 9, and a protective cap 12 using a hard vinyl chloride pipe is provided on the outside thereof. I put it on.

As shown in FIG. 6, the ductile segment 2b on the face side is assembled, a press ring 13 having a width of about 30 cm is assembled on the face side of the ductile segment 2b, the bolt 9 is inserted through the ductile segment 2b, and the shield jack is slightly extended. The rubber gasket 8 was compressed to a predetermined thickness, and a nut was screwed on the ductile segment 2b side with an elastic washer 10 made of a natural rubber material and a steel washer 11 interposed therebetween, and a protective cap 12 was put on. Press Ring 13
Is for compressing the rubber gasket 8 evenly to a predetermined thickness. The compression of the rubber gasket 8 at the initial stage as described above is for securing the water stop both in the axial compression and in the axial tension. This is because it must be done.

Thus, the ductile segment 2
A rubber gasket 8 is sandwiched between a and 2b, and the rubber gasket 8 is fastened by penetrating a bolt 9. The bolt holes of the ductile segments 2a and 2b are slightly enlarged so that the bolt 9 can move.

As shown in FIG. 7, the temporary fixing member 14 is used as a thrust transmitting member and frictionally joined to the longitudinal ribs of the ductile segments 2a and 2b on both sides of the rubber gasket 8 by bolts.

As shown in FIG. 8, the shield machine is excavated by the shield jack, the roundness holding device 4 is moved to the temporary fixing member 14, the press ring 13 is disassembled, and the shield machine is excavated by the shield jack. When the thrust of the shield is no longer transmitted, the temporary fixing member 14 is dismantled.

The temporary fixing member 14 prevents the rubber gasket 8 from being excessively compressed by the jack, and can be used as a spacer so that the rubber gasket 8 can have a substantially uniform initial compression amount.

Before the secondary lining concrete 15 is cast, the inner cover plate 6 is attached, and an ethylene foam is installed between the outer cover plate 5 and the inner cover plate 6 and the rubber gasket 8 so that the inner cover plate 6 can be used at the time of back filling. Prevent the backfill material or concrete from flowing between the rings during the next lining work.

When performing the above-described operations, cambers are installed around and below the segments, and the positions of the segments and bolts are adjusted by using a lever block.

Next, the secondary lining concrete 15 is cast. A synthetic resin or rubber sealing material 16 is provided at the joint between the secondary lining concretes 15, and a water blocking plate 17 is laid across the sealing material 16, and butyl rubber or a water-swellable composition A sealing material 18 is disposed on the joint surface.

At the time of tunnel axial earthquake (tunnel axial tension)
As shown in FIGS. 16 and 17, the rubber gasket 8 is loosened (returned) and the elastic washer 10 is compressed at the portion a of the shield tunnel with respect to the shaft 19.

In the case of an earthquake perpendicular to the tunnel axis, FIG.
As shown in FIG. 19, the rubber gasket 8 undergoes shear deformation and the elastic washer 10 also undergoes bending / shear deformation at the a portion of the shield tunnel with respect to the shaft 19. At this time, since there is a clearance between the bolt 9 and the bolt holes of the ductile segments 2a, 2b, the bolt 9 can follow the shear deformation.

[0033]

As described above, the earthquake-resistant flexible joint of the shield segment of the present invention and the method of constructing the same use a rubber gasket for the compression member and a bolt + elastic washer for the tension member to reduce the compression stiffness of the tunnel. Flexible structure with reduced tensile stiffness and bending stiffness, which can be simple and inexpensive and can follow shear deformation without using expensive specially structured flexible segments. It is.

Further, the press-fitting property of the rubber gasket can be improved to secure the water stopping property, and the resistance against the escape by the external pressure can be increased.

In addition to this, it is possible to prevent the backfill material or concrete from flowing into the space between the rings during backfill and during the secondary lining work. By preventing excessive compression due to thrust, and using a temporary fixing material as a spacer,
The rubber gasket can have a substantially uniform initial compression amount.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a main part showing one embodiment of a flexible joint for earthquake resistance of a shield segment of the present invention.

FIG. 2 is a longitudinal sectional side view showing one embodiment of a flexible joint for earthquake resistance of a shield segment of the present invention.

FIG. 3 is a plan view showing one embodiment of an earthquake-resistant flexible joint of the shield segment of the present invention.

FIG. 4 is a vertical sectional side view of a first step showing one embodiment of a method of constructing an earthquake-resistant flexible joint for a shield segment.

FIG. 5 is a vertical sectional side view of a second step showing one embodiment of a method of constructing an earthquake-resistant flexible joint for a shield segment.

FIG. 6 is a vertical sectional side view of a third step showing one embodiment of a method of constructing an earthquake-resistant flexible joint for a shield segment.

FIG. 7 is a vertical sectional side view of a fourth step showing one embodiment of a method of constructing an earthquake-resistant flexible joint for a shield segment.

FIG. 8 is a vertical sectional side view of a fifth step showing one embodiment of a method of constructing an earthquake-resistant flexible joint for a shield segment.

FIG. 9 is a longitudinal sectional side view of a sixth step showing one embodiment of a method of constructing an earthquake-resistant flexible joint for a shield segment.

FIG. 10 is a longitudinal sectional side view of a rubber gasket.

FIG. 11 is an explanatory view of an elastic washer.

FIG. 12 is a side view of the outer cover plate.

FIG. 13 is a sectional view taken along line AA of FIG.

FIG. 14 is a side view of the inner cover plate.

FIG. 15 is a sectional view taken along line BB of FIG. 14;

FIG. 16 is an explanatory diagram at the time of a tunnel axial earthquake.

FIG. 17 is a detailed view of a part a of FIG. 16;

FIG. 18 is an explanatory view at the time of an earthquake perpendicular to the tunnel axis.

FIG. 19 is a detailed view of a part a in FIG. 18;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... RC segment 2a, 2b ... Ductile segment 3 ... Skin plate 4 ... Roundness holding device 5 ... Outer cover plate 6 ... Inner cover plate 7 ... Rib 8 ... Rubber gasket 8a ... Bolt hole 9 ... Bolt 10 ... Elastic washer 11 ... Steel washer 12 ... Protective cap 13 ... Press ring 14 ... Temporary fixing material 15 ... Secondary lining concrete 16 ... Seal material 17 ... Water stop plate 18 ... Seal material 19 ... Pit shaft

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuhiko Suzuki 34 Shiomicho, Minato-ku, Nagoya-shi, Aichi Prefecture Inside Shin-Nagoya Thermal Power Plant of Chubu Electric Power Co., Inc. 14 Kashima Construction Co., Ltd., Nagoya Branch (72) Inventor Yoshinobu Suzuki 14 Kashima Construction Co., Ltd., Nagoya Branch, Nagoya City, Aichi Prefecture 14 (72) Inventor Toyofumi Ikematsu 1-Chome Moto-Akasaka, Minato-ku, Tokyo 2-7 Kashima Construction Co., Ltd. (72) Inventor Masayoshi Nakagawa 1-7 Motomoto Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd.

Claims (5)

[Claims] 1. A rubber gasket is provided between ductile segments, and a segment fastening bolt that penetrates the rubber gasket is inserted into a bolt hole of the ductile segment, which is somewhat larger, to interpose an elastic washer and a large steel washer. An earthquake-resistant flexible joint for a shield segment, characterized in that: 2. The flexible joint according to claim 1, wherein the seam of the rubber gasket is cut obliquely, wrapped and crimped. 3. The flexible joint according to claim 1, wherein the rubber gasket is attached to the segment with an adhesive and compressed to a predetermined thickness. 4. A cover plate is provided on the outer periphery and inner periphery of the ring joint surface of the segment, ethylene foam is provided in a gap between the cover plate and the gasket, and a protective cap is provided around the elastic washer. 4. The flexible joint for earthquake resistance of the shield segment according to any one of 3. 5. A rubber gasket is provided between ductile segments, segments are assembled with elastic washers and large steel washers interposed between segment fastening bolts penetrating the rubber gasket, and the temporary fixing material is used as a thrust transmitting material. A method for constructing an earthquake-resistant flexible joint for a shield segment, wherein a bolt is friction-bonded to longitudinal ribs of ductile segments on both sides sandwiching the rubber gasket.