JPH0613918Y2 - Steel segment - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a steel segment as a primary lining for use with concrete for a secondary lining in a shield construction method or a vertical shaft.

[Conventional technology]

As shown in FIGS. 6 to 8, a conventional general steel segment forms a pair of arc-shaped main girders 2 forming a joint surface in the tunnel direction and a joint surface in the circumferential direction. The pair of joint plates 3 and the skin plate 1 forming the outer surface of the segment are formed in a box shape, and the main girders 2 are connected by a plurality of vertical ribs 8 (for example,
See Japanese Utility Model Publication No. 56-77600 and Japanese Utility Model Publication No. 58-6899).

By the way, in general, when constructing a tunnel by the shield construction method, in most cases, the secondary lining is constructed after the primary lining. However, both linings have different design target loads, the primary lining shall resist earth pressure and water pressure, and the secondary lining should be built internally in a tunnel for water and sewerage or newly built in the future. It is believed to resist the added loads of the construct. In addition, when constructing the secondary lining, unreinforced concrete is placed inside the steel segment box, but this is not considered at all in the design.

[Problems to be solved by the device]

If designed in accordance with the above concept, the reinforcement of the secondary lining for concrete will be double rebar, which will require more labor for construction and increase the lining thickness.In order to secure the required inner diameter, steel as the primary lining is required. There is no choice but to increase the outer diameter of the segment.

Therefore, it is desired to have a structure in which the primary lining and the secondary lining are integrated for the purpose of effectively evaluating concrete and reducing the construction cost of the shield.

Regarding the joint portion where stress is concentrated, the joint in the tunnel axial direction is stiffened by connecting a plurality of vertical ribs between the front and rear main girders, but for the circumferential joint portion, for example, Means such as the provision of triangular stiffening ribs between the joint plate and the skin plate, as seen in Japanese Utility Model Publication No. 44598/44, is adopted. But usually
Since the skin plate is thin and has a lower bending rigidity than the joint plate, not only the stiffening effect cannot be expected due to the deformation of the skin plate, but also the skin plate may be adversely affected.

The present invention is intended to solve the above-mentioned problems in the prior art, and enhances the integration of the steel segment as the primary lining and the concrete of the secondary lining as a composite structure. An object of the present invention is to provide a structure of a steel segment capable of effectively stiffening a circumferential joint portion.

[Means for Solving the Problems]

The present invention is configured in a box shape with a pair or a plurality of main girders forming a joint surface in the tunnel direction, a pair of joint plates forming a joint surface in the circumferential direction, and a skin plate forming an outer surface of a segment. In a steel segment as a primary lining that connects the main girders with a plurality of vertical ribs, a shear connector is provided on the inner surface of the joint plate for integration with the secondary lining concrete. , Furthermore, by connecting the inner surface of the joint plate and the vertical rib closest to the joint plate among the vertical ribs with a rib-shaped connecting steel plate, with the concrete of the secondary lining to be placed later. It is one that enhances the unity as a synthetic structure.

The rib-shaped connecting steel plate has a function of enhancing the integrity of the steel segment as the primary lining and the concrete of the secondary lining, and a stiffening rib for stiffening the circumferential joint portion where stress is concentrated. However, since the inner surface of the joint plate and the vertical ribs are directly connected, deformation of the skin plate can be suppressed and a reliable stiffening effect can be obtained, which is further integrated with the secondary lining concrete. It is connected with improving sex.

Example Next, the illustrated example will be described.

1 to 5 show an embodiment of the present invention. The steel segment main body is a box type with a pair of main girders 2 forming a joint surface in the tunnel direction, a pair of joint plates 3 forming a joint surface in the circumferential direction, and a skin plate 1 forming an outer surface of the segment, as in the conventional case. The main girders 2 are connected by a plurality of vertical ribs 8. The joint plate 3 is provided with bolt holes 4 for bolting the segments in the circumferential direction, and although not shown, the main girder 2 is usually a bolt hole for bolting the segments in the tunnel direction. Has been drilled.

In this embodiment, as best shown in FIG. 1 and FIG. 5, a plurality of stud dowels 5 are welded to the inner surface of the joint plate 3 and the secondary lining is placed inside the steel segment. We are trying to integrate with concrete 7.

Also, as best shown in FIGS. 1 and 4,
By directly connecting the inner surface of the joint plate 3 and the vertical rib 8 closest to the joint plate 3 with the connecting steel plate 6, the deformation of the skin plate 1 which is thin and easily deformed is suppressed, and the joint which hits the joint portion in the circumferential direction. It firmly stiffens the plate 3 and further enhances its integrity with the concrete 7.

FIG. 3 shows a case where the main girder 2 is plural in number, as compared with FIG.

Further, instead of the stud dowel 5 in this embodiment, a reinforcing bar or the like may be implanted.

[Effect of device]

The steel segment as the primary lining and the concrete for the secondary lining can be integrated with each other by the connecting steel plate provided on the inner surface of the joint plate and the stud dowel or the reinforcing bar as the shear connector.

In addition to the above effects, by directly connecting the joint plate and the vertical ribs with the connecting steel plate, the joint portion in the circumferential direction is effectively stiffened while the deformation of the skin plate is suppressed, and the deformation of the skin plate is prevented. It can be suppressed to further enhance the integrity with concrete.

Therefore, by design, the steel segment can be regarded as a tensile rebar, and what was conventionally a composite rebar in the secondary lining is now a single rebar, and the amount of rebar and the secondary lining thickness can be reduced.
It also leads to a reduction in the amount of excavated soil during construction.

[Brief description of drawings]

FIG. 1 is a bottom view of a segment in one embodiment of the present invention, FIG. 2 is a side view, FIG. 3 is a side view when a main girder is also located in the center of the segment, and FIG. Fig. 5 is a vertical sectional view in the vicinity of a joint plate, Fig. 5 is a vertical sectional view in the vicinity of a joint plate showing a mounting state of a stud dowel, Fig. 6 is a bottom view showing a conventional example, Fig. 7 is a side view, and Fig. 8 FIG. 6 is a side view of a conventional example in which a main girder is also located in the center of a segment. 1 ... Skin plate, 2 ... Main girder, 3 ... Joint plate, 4
...... Bolt hole, 5 stud stud, 6 connection steel plate, 7 concrete, 8 vertical rib

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Haruki Kaiho 2-12-11 Shimbashi, Minato-ku, Tokyo Yamamoto Kenzai Lease Co., Ltd. (72) Hideyuki Ishida 1-3-1 Otemachi, Chiyoda-ku, Tokyo No. Sumitomo Metal Industries Co., Ltd. (56) Bibliographic data Sho 49-104126 (JP, U) Real development Sho 51-93129 (JP, U) Real development Sho 50-69835 (JP, U) Real development Sho 58 -6899 (JP, U) Showa 44-4598 (JP, Y1)

Claims (1)

[Scope of utility model registration request] 1. A box-shaped structure comprising a pair or a plurality of main girders forming a joint surface in the tunnel direction, a pair of joint plates forming a joint surface in the circumferential direction, and a skin plate forming an outer surface of a segment. In the steel segment as the primary lining that connects the main girders with a plurality of vertical ribs, a shear connector for achieving integration with the secondary lining concrete is provided on the inner surface of the joint plate. A steel segment, characterized in that the inner surface of the joint plate and the vertical rib closest to the joint plate among the vertical ribs are connected by a rib-shaped connecting steel plate.