JP3801419B2 - Tunnel segment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
INDUSTRIAL APPLICABILITY The present invention is for a box-shaped metal tunnel in which a tunnel inner wall can be formed by connecting a large number in the circumferential direction and the axial direction of the tunnel and connecting each other, and a skin plate is supported by a plurality of main girders and joint plates. Regarding segments.
[0002]
[Prior art]
Conventionally, as this kind of tunnel segment 1, as shown in FIG. 10, the thickness of the skin plate 2 is made uniform over the entire width, and the joint 6 between the main beam 3 and the skin plate 2. Was formed in an acute angle shape.
[0003]
[Problems to be solved by the invention]
According to the above-described conventional tunnel segment 1, as shown in FIG. 10, the joint 6 between the main beam 3 and the skin plate 2 is formed in an acute angle. When stress due to pressure is applied, the stress concentrates on the joint 6 and is easily buckled. Therefore, when the width of the tunnel segment 1 is widened, the width can be widened to withstand the buckling due to the stress concentration. It is necessary to increase the thickness of the skin plate 2 over the entire width to ensure the required strength according to the width. As a result, there is a problem that not only the weight of the tunnel segment 1 itself is increased, but also the material cost is increased because a large amount of material for forming the skin plate 2 is required.
[0004]
Therefore, the object of the present invention is to eliminate the above-mentioned problems and to suppress the increase in weight as compared with the conventional tunnel segment even when the width of the tunnel segment is widened, and the material cost is high. The present invention is to provide a tunnel segment that can secure the necessary strength according to the width of the tunnel while suppressing the above.
[0005]
[Means for Solving the Problems]
〔Constitution〕
As shown in FIG. 4, the characteristic configuration of the invention of claim 1 is that the inner wall of the tunnel can be formed by connecting a large number of them in the circumferential direction Y and the axial direction of the tunnel and connecting them to each other. A box-shaped metal tunnel segment formed by supporting and supporting the plate 2, wherein the thickness of the skin plate 2 is formed so as to increase toward the main beam 3 side.
[0006]
The characteristic configuration of the invention of claim 2 is that, as illustrated in FIGS. 8 and 9, the thickness of the skin plate 2 is formed to be thicker toward the joint plate 4 side.
[0007]
In addition, as mentioned above, although the code | symbol was written in order to make contrast with drawing convenient, this invention is not limited to the structure of an accompanying drawing by this entry.
[0008]
[Action and effect]
According to the invention of claim 1, since the thickness of the skin plate is formed so as to be thicker toward the main girder side, even if the width of the tunnel segment is widened, the necessary strength corresponding to the width is secured. Therefore, it is not necessary to increase the thickness of the skin plate over the entire width.
In other words, the joint between the main girder and the skin plate becomes obtuse when the thickness of the skin plate is increased toward the main girder, so that the tunnel segment is subjected to stress due to bending stress or earth pressure. However, since it can flow smoothly without concentrating stress on the joint, it can be made difficult to buckle. Therefore, even if the width of the tunnel segment is widened, it is not necessary to increase the thickness of the skin plate over the entire width as in the conventional case. Especially, the thickness of the skin plate at a position away from the main girder side is not required. Even if it is not as thick as the conventional one, the required strength according to the width can be ensured.
As a result, it is possible to suppress the increase in weight compared to the conventional tunnel segment and to ensure the necessary strength according to the width while suppressing the increase in material cost. became.
[0009]
According to the invention of claim 2, in addition to being able to achieve the operational effect of the invention of claim 1, the thickness of the skin plate is formed so as to be thicker toward the joint plate side, Even if the length of the tunnel segment is increased, it is not necessary to increase the thickness of the skin plate over the entire length in order to ensure the necessary strength according to the length.
In other words, the joint between the joint plate and the skin plate is formed so that the thickness of the skin plate becomes thicker toward the joint plate side, so even if bending stress or stress due to earth pressure is applied to the tunnel segment, Since it can flow smoothly without concentrating stress on the joint, it can be made difficult to buckle. Therefore, even if the length of the tunnel segment is increased, it is not necessary to increase the thickness of the skin plate over the entire length as in the conventional case, especially the thickness of the skin plate at a position away from the joint plate side. The required strength according to the length can be ensured without increasing the thickness of the conventional one.
As a result, it is possible to suppress the increase in weight as compared with the conventional tunnel segment and to ensure the necessary strength according to the length while suppressing the increase in material cost. Became.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.
In the drawings, the parts denoted by the same reference numerals as those in the conventional example indicate the same or corresponding parts.
[0011]
1-4, the inner wall of the tunnel can be formed by connecting a large number in the circumferential direction Y and the axial direction X of the tunnel, and the skin plate 2 is supported and formed by a plurality of main girders 3 and joint plates 4. A box-shaped metal segment (specifically made of ductile cast iron) is shown.
[0012]
As shown in FIG. 1, the tunnel segment 1 (hereinafter abbreviated as a segment) is composed of three different shapes, ie, a first segment 11, a second segment 12, and a third segment 13, which are tunneled. A tunnel ring TR is constructed by bolting together in the circumferential direction Y and the axial direction X.
[0013]
As shown in FIG. 1A, the first segment 11 is formed in a rectangular shape in plan view and has a shape curved along the tunnel circumferential direction Y, and the end of the first segment 11 Among these, the surface direction of the butting surface T1 provided at both ends on the tunnel circumferential direction Y side for connecting to the adjacent second segment 12 is formed in a surface direction that coincides with the radial direction of the tunnel.
[0014]
As shown in FIGS. 1B and 1C, the second segment 12 includes two types, a second right segment 12R and a second left segment 12L. The second right segment 12R and the second left segment 12L Each of the segments 12L is formed in a symmetrical shape, and each of the segments is formed in a trapezoidal shape in plan view that spreads toward the shaft side, and has a shape curved along the circumferential direction Y of the tunnel. Of the two ends of the second segment 12 on the Y side in the circumferential direction of the tunnel, a butt end that is adjacent to the first segment 11 and connected to the first segment 11 is formed on the butt surface T1 that is aligned with the radial direction of the tunnel. In addition, when the second segment 12 is constructed as a tunnel ring TR, the butt end portion of the second segment 12 adjacent to the third segment 13 and connected to the third segment 13 is the third segment 13. Formed in a shape corresponding to the abutment surfaces T2 of segment 13 are constituted.
[0015]
As shown in FIG. 1 (d), the third segment 13 has a shape curved along the tunnel circumferential direction Y, and is adjacent to the second right segment 12R and the second left segment adjacent in the tunnel circumferential direction Y. The abutting surfaces T2 of two sides facing the segment 12L are formed in a trapezoidal shape in plan view that becomes narrower toward the shaft side along the abutting surface T2 of each second segment 12.
[0016]
The segments are connected as follows.
As shown in FIG. 2, first, the three first segments 11 are arranged below and connected and fixed to each other.
Next, the second right segment 12R is connected and fixed to the right side of the plurality of connected first segments 11, and the second left segment 12L is connected and fixed to the left side thereof.
As shown in FIGS. 2 and 3, the third segment 13 is pushed upward and inserted into the upper space formed by the second right segment 12R and the second left segment 12L, and then the tunnel axis direction The third segment 13 is set by a pushing operation from the face side to the shaft side to X, and the tunnel ring TR is formed by connecting and fixing the adjacent second right segment 12R and second left segment 12L.
The segments 1 are connected to each other by inserting bolts into bolt holes provided in the adjacent butting surfaces T1 and T2 and fastening them.
In addition, the upper direction of the paper surface in FIG. 3 is the shaft side, and the lower direction is the face side.
[0017]
As shown in FIG. 1, each segment 1 has a plurality of main girders 3 extending in the tunnel circumferential direction Y on the inner side in the tunnel radial direction of the skin plate 2 (in this embodiment, four main girders are shown). And a joint plate 4 that forms abutting surfaces T1 and T2 for connecting to adjacent segments 1 and a plurality of reinforcing ribs 5 extending between the plurality of main girders 3 in the tunnel axis direction X. The support is formed.
[0018]
As shown in FIG. 4, the skin plate 2 is formed in a thick shape having an inclined surface 7 that gradually becomes thicker from the substantially middle part of the main girders 3 toward the main girder 3 side. In this case, since the joint 6 between the main girder 3 and the skin plate 2 is obtuse, even if bending stress or stress due to earth pressure is applied to the segment 1, the stress is not concentrated on the joint 6 smoothly. Since it can flow, it can be made difficult to buckle. Therefore, when the wide segment 1 is formed, it is not necessary to increase the thickness of the skin plate 2 over the entire width unlike the conventional one, so that the weight is heavier than the conventional segment 1. While being able to suppress the increase in material cost, the required strength according to the width can be ensured.
[0019]
[Another embodiment]
Other embodiments will be described below.
<1> The shape of the skin plate 2 that becomes thicker toward the main beam 3 side is not limited to the shape that gradually increases from the substantially middle part of the main beams 3 described in the previous embodiment. For example, as shown in FIG. Alternatively, it may be formed in a thick shape having an inclined surface 7 that gradually becomes thicker toward the main girder 3 side from the main girder 3 side than the substantially middle part of the main girder 3.
<2> The shape of the skin plate 2 that becomes thicker toward the main girder 3 side is not limited to the above-described configuration. For example, as shown in FIG. Alternatively, it may be formed in a thick shape having a plurality of inclined surfaces 7 (in this embodiment, two steps) that become thicker toward the main beam 3 side. The number of steps for forming the inclined surface is not limited to the above-described configuration, and is arbitrary.
<3> The shape of the skin plate 2 that becomes thicker toward the main girder 3 side is not limited to the above-described configuration. For example, as shown in FIG. It may be formed.
<4> The shape of the skin plate 2 is not limited to the shape that becomes thicker toward the main girder described in the previous embodiment. For example, as shown in FIG. It may be formed into a thick shape having In this case, since the joint 6 between the joint plate 4 and the skin plate 2 is obtuse, even if bending stress or stress due to earth pressure is applied to the segment 1, the joint 6 is smoothly concentrated without stress concentration. Since it can flow, it can be made difficult to buckle. Therefore, when the segment 1 having a long length is formed, it is not necessary to increase the thickness of the skin plate 2 over the entire width unlike the conventional one, so that the weight is heavier than the conventional segment 1. While being able to suppress becoming, and suppressing that material cost becomes high, the required intensity | strength according to the width | variety can be ensured.
Moreover, as shown in FIG. 9, the thickness of the skin plate 2 may be formed with an inclined surface 7 (or curved surface 8) that becomes thicker toward the reinforcing rib 5 side. This can further increase the segment strength against bending stress and stress due to earth pressure.
[Brief description of the drawings]
FIG. 1 is a bottom view showing a tunnel segment according to an embodiment of the present invention. FIG. 2 is a front view showing an assembled state of the tunnel segment according to an embodiment of the present invention. FIG. 4 is an explanatory view showing an assembled state of a tunnel segment. FIG. 4 is an enlarged vertical side view of a tunnel segment according to an embodiment of the invention. FIG. 5 is an enlarged vertical side view of a tunnel segment according to another embodiment of the invention. 6 is an enlarged longitudinal side view of a tunnel segment according to another embodiment of the present invention. FIG. 7 is an enlarged longitudinal side view of a tunnel segment according to another embodiment of the present invention. FIG. 8 is a tunnel segment according to another embodiment of the present invention. Fig. 9 is an enlarged vertical front view of a main part of a tunnel segment according to another embodiment of the present invention. Fig. 10 is a conventional tunnel segment. Longitudinal side view of a cement EXPLANATION OF REFERENCE NUMERALS
1 Tunnel segment 2 Skin plate 3 Main girder 4 Joint plate Y Circumferential direction X Axial direction

Claims (2)

It is a box-shaped metal tunnel segment that can form the inner wall of the tunnel by connecting a large number in the circumferential direction and axial direction of the tunnel, and supporting the skin plate with a plurality of main girders and joint plates. The tunnel segment is formed so that the thickness of the skin plate increases toward the main girder. The tunnel segment according to claim 1, wherein the thickness of the skin plate is formed so as to increase toward the joint plate side.

Images