JP2629919B2 - Shield segment composite version structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a structural material combining a steel plate and concrete.

[Prior Art] Conventionally, segments used in shield tunnels are mainly made of concrete RC or metal-based steel or ductile cast iron. However, they all have disadvantages such as easy corner loss, low rigidity, and high cost.

On the other hand, the closed rigid segment is being developed as a rational structural method for solving the above-mentioned disadvantages, and has the following advantages.

The outer steel shell can be used as a formwork when casting concrete.

Since it is covered with a steel shell, it is unlikely to cause breakage and the assembling work is easy.

Because of the closed structure, both the strength and toughness of the segment body are high.

Although the joint is a weak point of the segment, the steel shell is effectively used to enable a high strength and high rigidity joint.

FIG. 3 is a perspective view showing a shield and a segment.
In the figure, 1 is a shield, 2 is a segment, 3 is a steel shell, 4 is a main girder plate, 5 is a joint plate, 6 is a skin plate,
7 is a concrete injection hole, 8 is an air hole, 9 is concrete, and 10 is a stud.

As shown in the figure, the segment 2 is configured by injecting concrete 9 from a concrete injection hole 7 into a steel shell 3 formed of a steel plate.

The stud 9 welded to the inner surface of the skin plate 6
This is to help the concrete 9 and the steel shell 3 adhere to each other. As shown in FIG.
Is welded to the skin plate 6.

[Problems to be Solved by the Invention] By the way, in order to completely bond the concrete 9 and the steel shell 3 of the segment 2, the stud 10 or the reinforcing bar is used.
11 is used, but for stud 10, steel shell 3
When a displacement force acts between the steel shell 3 and the concrete 9, the displacement is likely to occur between the steel shell 3 and the concrete 9 unless the studs 10 are welded very tightly. Also rebar
As for 11, the welding is troublesome in welding to the steel shell 3, which is disadvantageous in that the cost is increased. Thus, the conventional segment still has problems.

The present invention has been made in order to solve the above-mentioned problems of the conventional segment, and an object of the present invention is to provide a segment in which the adhesion between the steel shell 3 and the concrete 9 therein is completely close.

[Means for Solving the Problems] In order to achieve the above object, in the segment according to the present invention, a stud is welded to a side having a projection of a steel plate with a projection, and the side having the projection and the stud is attached to an inner surface of a skin plate. As a steel shell.

[Operation] Since the steel shell of the segment according to the present invention is configured as described above, when concrete is poured into the steel shell, the effect of combining the concrete and the steel shell is greatly improved.

Embodiment of the Invention FIG. 1 (a) is a partial sectional view of a segment showing an embodiment of the present invention, and FIG. It is a protrusion.

As shown in the drawing, a steel plate 20 having a projection on which a stud 10 is welded is formed as a skin plate 6, a steel shell 3 is formed on the projection side on the inner surface, and concrete 9 is poured into the steel shell 3 to obtain a segment. Constituting No. 2.

In the segment 2 thus constructed, the degree of synthesis of the steel shell 3 and the concrete 9 is greatly improved by the projections 21 and the studs 10 on the inner surface of the skin plate as compared with the conventional steel shell. Occurrence of displacement and separation between the concrete 9 and the concrete 9 is greatly suppressed.

[Effect of the Invention] In the present invention, in the segment used for the shield, a steel plate with projections is used for the skin plate constituting the steel shell, and the projection side where the stud is welded is formed on the inner surface to form the steel shell. The adhesion between the steel shell and the concrete was greatly improved, and the phenomenon of displacement between the steel shell and the concrete and separation of the steel shell from the concrete was greatly reduced.

FIG. 2 is a diagram showing the effect of the present invention, wherein A is the load of the segment according to the present invention, B is the load of the conventional segment which pursued economy, and C is the load of the segment welded tightly by reducing the pitch of the stud. This shows the displacement with respect to. It can be seen that the segment A according to the present invention has a reduced displacement and is improved compared to the conventional segment B. In the figure, the straight line ignoring the initial stiffness and the tension side concrete is
Each is an effect by calculation, and n indicates the ratio of the elastic modulus between steel and concrete.

[Brief description of the drawings]

1 (a) is a partial side sectional view, FIG. 1 (b) is a plan sectional view, and FIG.
FIG. 3 is a diagram showing the relationship between load and displacement, FIG. 3 is a perspective view of a shield and a conventional segment, FIG. 4 (a) is a partial sectional view of a segment using a stud, and FIG. It is a partial sectional view of a segment using a reinforcing bar. In the figure, 2 is a segment, 3 is a steel shell, 6 is a skin plate,
9 is concrete, 10 is a stud, 11 is a reinforcing bar, 20 is a steel plate with a projection, and 21 is a projection.

Claims (1)

(57) [Claims] 1. A shield segment composite plate structure, wherein a steel plate with a projection is used for a skin plate constituting a steel shell, and a steel shell is formed with a projection side on which a stud of the steel plate with a projection is welded as an inner surface. .