JP3948955B2 - Tunnel segment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tunnel segment for forming a tunnel inner wall by connecting a large number of them in the circumferential direction of the tunnel and in the tunnel axis direction, and more particularly to a metal segment such as cast iron.
[0002]
[Prior art]
When the tunnel segments are connected and integrated to form a tunnel ring (tunnel), when the ground to be excavated is relatively soft soil, the ground flows due to the action of earth pressure, so that it contacts the outer periphery of the segment without any gaps. It becomes integrated and a relatively stable tunnel strength state is obtained, but when it is hard soil such as rock, there is a gap between the outer periphery of the segment and the ground around the tunnel is not stabilized Sometimes.
[0003]
In such a case, after forming the tunnel ring by connecting the segments, the gap filler such as grout is poured and supplied using the through holes formed in advance in the state extending between the inner peripheral side and the outer peripheral side of the segment. Thus, a process of filling the gap space between the ground and the outer periphery of the tunnel ring is performed. As a tunnel segment in which such a through hole is formed, one disclosed in Japanese Patent Application Laid-Open No. 10-29648 is known. That is, a through hole (grouting hole) is provided by projecting the outer periphery partly in a cylindrical shape in the outer diameter direction, and basically a screw cover is provided and the through hole is covered. . When necessary, the screw lid is removed and the grout is injected into the outer periphery of the tunnel.
[0004]
[Problems to be solved by the invention]
In the publication, as shown in FIG. 3 and the like, a male screw-shaped injection hole plug 1 and a ring packing 10 in which a shock absorber 8 is housed in a through hole 2 having an internal thread portion 4 formed on the inner surface. The structure is such that a plurality of components such as the check valve 11 and a mechanism are screwed, and the through hole 2 is configured to be shielded and openable. This is not to say that the through-hole is always used. If there is a gap between the tunnel ring and the outer periphery of the tunnel ring due to the soil quality of the ground to be tunneled, it is used for grout injection. It is usually blocked.
[0005]
If to try, through hole, the through-hole-stopper mechanism comprising a plurality of structural parts such plugs or the like, in spite of not know whether to use, is unreasonable that you also equipped in advance which segment However, it is also disadvantageous in terms of cost, and there seems to be room for improvement.
[0006]
The object of the present invention is to reduce the number of parts required for the through-hole / plug mechanism by devising the through-hole formed in the outer periphery of the segment for grout injection and its plug structure, and is advantageous in cost. The point is to get a segment.
[0007]
[Means for Solving the Problems]
〔Constitution〕
The configuration of claim 1 is a tunnel segment for forming a tunnel inner wall by connecting a large number in the circumferential direction and the tunnel axis direction of the tunnel as illustrated in FIG.
A box-like metal having a curved plate portion 1c forming a tunnel outer peripheral portion, a pair of arc-shaped plate portions 1a, 1a at both ends in the tunnel axial direction, and a pair of end face plate portions 1b, 1b at both ends in the tunnel circumferential direction. And a thick wall portion 14 in which a grout injection through hole 13 can be formed in the middle portion of the curved plate portion 1c in the circumferential direction of the tunnel in a circular range larger than the diameter of the through hole 13 wherein the are form shaped such that the thickness than.
[0008]
The structure of claim 2 is made of cast iron having a rib portion 1f extending in the tunnel axis direction in a state extending between the pair of arcuate plate portions 1a and 1a in the structure of claim 1 as illustrated in FIG. The thick portion 14 is formed between a pair of adjacent rib portions 1f and 1f at the center or substantially at the center in the circumferential direction of the tunnel.
[0009]
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.
[0010]
[Action]
According to the structure of Claim 1, there exists the following effect | action. That is, since the structure of Claim 1 is a box-shaped metal segment by the 5 surface part of an outer peripheral part, a pair of circular arc-shaped board part, and a pair of end surface board part, the strength and rigidity required as a segment are ensured. However, the wall thickness itself can be reduced to reduce the weight. And since the thick part thicker than the surroundings was formed in the outer peripheral part, when a through-hole such as grout injection is necessary to fill the gap with the rock mass on the outer peripheral side as a tunnel, the thick part is A through hole is formed and used.
[0011]
In other words, since it is not often used as a through-hole, when it is used, the thickness is increased in advance so that the hole can be formed by post-processing so that the strength does not decrease even if the hole is formed. It is means that. According to this, when the through hole is unnecessary, there are no additional parts, and the cost is not increased. Further, when a through hole is necessary, a through hole is formed in a thick portion of the required segment, and processing such as grout injection is performed. After the use of the through hole, it is closed by solidified grout, so there is no need to do anything, or a lid (cap) is press-fitted, or a hole is closed by welding a patch plate. It is free.
[0012]
According to the configuration of claim 2, the thick-walled portion in the cast iron segment having a bottomless box-like shape and having a plurality of rib portions extending in the tunnel axis direction is defined, The thick part is provided between the ribs in the vicinity, so the shape of the tunnel is good in balance in the circumferential direction of the tunnel, and the ribs are difficult to obstruct the work such as grout injection when the through hole is opened. Is also preferable.
[0013]
〔effect〕
In the tunnel segment according to claim 1, the idea is changed, and a segment that requires a through hole for grout injection or the like is provided with a thick portion, and the thick portion is penetrated by post-processing. Through a means that prevents the strength from being reduced even if holes are formed, it is possible to obtain the necessary functions by forming the through-holes without reducing the strength, while increasing the number of parts and increasing the cost. The stopper mechanism can be eliminated, and an economical and reasonable segment can be provided.
[0014]
In the tunnel segment according to claim 2, in the cast iron segment having a plurality of rib portions extending in the tunnel axis direction, the shape balance is deteriorated due to the thick portion (for example, due to a shift of the center of gravity during segment transportation or segment assembly). There is an advantage that the above-described effect can be achieved by the configuration of claim 1 in a state in which there is no problem or the like and the grout injection work from the through hole is easy.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a tunnel ring TR constituted by using tunnel segments SA, SB and SK according to the present invention, and FIG. 2 shows a standard A segment SA. A single unit tunnel ring tr in the direction of the tunnel axis (direction of arrow A) has one K-type segment SK among these three types of segments SA, SB, SK, and A-type and B-type segments SA, SB. A total of five segments of two each are connected in the tunnel circumferential direction (arrow B direction).
[0016]
The A-type segment SA has a symmetrical shape in both the tunnel circumferential direction and the axial direction, and the total length angle in the circumferential direction is set to 85.714 degrees. The B-type segment SA is basically the same as the A-type segment SA, but is moved between the pair of B-type segments SB and SB by moving the K-type segment SK from the inner diameter side to the outer diameter side (see FIG. 1). However, the only difference is that the circumferential end surface 2b in one tunnel circumferential direction is inclined in the direction of narrowing toward the inner diameter side with respect to the radial line (see FIG. 6).
[0017]
The K-shaped segment SK has a short basic angle of 17.143 degrees in the tunnel circumferential direction, and both circumferential end surfaces 5b and 5b are inclined opposite to the circumferential end surface 2b of the B-shaped segment SB. (See FIG. 7). Each segment S (SA, SB, SK) is made of ductile cast iron, and its structure will be described from an A-type segment SA which is a basic shape.
[0018]
-About type A segment SA-
As shown in FIGS. 2 to 5, the A-type segment SA is a substantially arc-shaped axial end surface (an example of an arc-shaped plate portion) 1 a and 1 a that is an end surface in the tunnel axis direction, and an end surface in the tunnel circumferential direction. Circumferential end faces (an example of an end face plate portion) 1b, 1b, an outer peripheral surface (an example of a curved plate portion) 1c, two vertical ribs 1g, 1g substantially the same type as the axial end face 1a, and the tunnel axial direction It is configured in a frame shape having a large number of lateral ribs (an example of rib portions) 1f.
[0019]
A first bolt hole 4 (an example of a connecting portion R) for connecting a bolt and a nut to adjacent segments in the axial direction of the tunnel is formed in the axial end faces 1a and 1a at an equal angle D [about 17.143 in the circumferential direction of the tunnel. Degrees (1/5 of the entire angle of the A-type segment SA)], and the circumferential end faces 1b and 1b are connected to the adjacent segments in the tunnel circumferential direction by bolts and nuts. Two bolt holes 3 are formed at a total of four locations, two at each end in the tunnel axis direction.
[0020]
The lateral ribs 1f are formed in a unified state in a direction parallel to the normal line Z passing through the center in the circumferential direction of the tunnel as the segment SA, for the convenience of the die-cutting direction during casting. The reference position for arranging the horizontal ribs 1f at equal angles in the circumferential direction of the tunnel is the tip position of the horizontal rib 1f. That is, the center point Y is the reference point in the width direction of the front end of the lateral rib 1f, and the center point Y is arranged at every equal angle d [about 8.571 degrees (1/10 of the entire angle of the A-type segment SA)]. Yes.
[0021]
However, the first and second angles w1, w2 between the pair of lateral ribs 1F, 1F located at the end in the circumferential direction of the tunnel and the circumferential end surface 1b are the angles between the adjacent lateral ribs 1f, 1f (8.571 degrees). ) Which is exactly half the value of 4.286 degrees. The space between the end lateral rib 1F and the circumferential end surface 1b is formed by a sand mold because of the relationship between the shape of the circumferential end surface 1b and the mold drawing direction. 2 and 4, the height of the end lateral ribs 1F, 1F is low except at the intersections with the axial end faces 1a, 1a and the longitudinal ribs 1g, 1g. Thus, it is easy for the sand to be taken in and out.
[0022]
In addition, the rib thickness at the four locations of the end lateral ribs 1F, 1F and the adjacent lateral ribs 1f, 1f is larger than the thickness of the other lateral ribs 1f (17 mm at the tip) (the end lateral rib 1F is at the tip). 28.5 mm, the adjacent lateral rib 1 f is reinforced by 27 mm at the tip). The circumferential end faces 1b and 1b are reinforced with a thick wall (25 mm). Further, two stages of sealing grooves 11 and 12 for filling a sealing material are formed on the four surfaces of both axial end faces 1a and 1a and both circumferential end faces 1b and 1b to fill a gap between adjacent segments.
[0023]
The circumferential direction angle D (1 pitch angle) between adjacent ones of the five first bolt holes 4 is set to 17.143 degrees which is twice the circumferential direction angle between the lateral ribs 1f and 1f, and The circumferential angle between the direction end face 1a and the adjacent first bolt hole 4 is set to 8.571 degrees (1/2 pitch angle), which is the same as the angle between the lateral ribs 1f and 1f. That is, in terms of angle, the first bolt holes 4 are located just in the center between the adjacent lateral ribs 1f and 1f, and are regularly arranged at a pitch twice that of the lateral ribs 1f and 1f. Further, the first bolt hole 4 portion is a thick portion 6 having a slightly increased thickness.
[0024]
A partial vertical rib 8 is formed between the pair of vertical ribs 1g and 1g and in a space 7 between the pair of central horizontal ribs 1f and 1f, and extends across the horizontal ribs 1f and 1f. The rib 8 is formed with an erector hole 9 for lifting by a crane or the like. Further, at three positions between the axial end face 1a and the vertical rib 1g and between the vertical ribs 1g and 1g in each horizontal rib 1f, drain holes 10 are formed at positions contacting the outer peripheral surface 1c.
[0025]
-About B type segment SB-
As shown in FIG. 6, the B-type segment SB is basically the same as the A-type segment SA except that one circumferential end face 2b is different as described above, and only the differences will be described. The circumferential end surface 2b for the K-shaped segment is formed on a surface inclined at an inward angle e (11.6 degrees) in a direction in which the inner diameter side approaches the adjacent lateral rib 1F side.
[0026]
As shown in FIG. 6, among a large number of space portions s in which the four surrounding surfaces are surrounded by the axial end surface 1 b and the vertical and horizontal ribs 1 g and 1 f, After construction of tunnel ring TR, a total of two thicknesses in which the wall thickness is increased in a large circular range so as to compensate for the strength reduction when the injection hole 13 for injecting grout into the space outside the tunnel ring TR is formed. The meat part 14 is formed in advance. That is, the B-shaped segment has a circular shape in a bottom view between the pair of adjacent rib portions 1f and 1f in the center in the circumferential direction of the tunnel and between the axial end surfaces 1a and 1a and the vertical ribs 1g. A thick portion 14 having a large thickness is formed.
[0027]
-About K-type segment SK-
The K-shaped segment SK has an extremely short basic circumferential angle k of 17.143 degrees, and has one first bolt hole 4 and two lateral ribs 1F and 1F in the circumferential direction. . Both circumferential end surfaces 5a, 5a are formed on a surface inclined at an outward angle g (11.6 degrees) in a direction in which the inner diameter side moves away from the adjacent lateral rib 1F, and the inward angle of the B-type segment SB e is set to cancel.
[0028]
[Another embodiment]
<< 1 >> As shown in FIG. 8, in the steel segment SS formed by welding and integrating steel plates, a circular steel plate (thickness is the same as or different from the outer peripheral surface 22) on the inner surface side (or outer surface side) of the outer peripheral surface 22. It is also possible to have a structure in which the thick portion 14 is formed by welding and integration of the (good) 23 by peripheral fillet welding or the like.
[0029]
<< 2 >> As shown in FIGS. 2 and 7, the thick portion 14 for the grout injection hole 13 employed in the B-type segment SB may be provided in the A-type segment SA or the K-type segment SK. In FIG. 3, the thick portion 14 shown in FIG. The thick portion 14 is provided at two locations at the center in the tunnel circumferential direction as in the A-type and B-type segments SA and SB at both ends in the tunnel axis direction, or at one location as in the K-shaped segment SK. Three or more locations may be provided apart in the direction, or three or more locations may be provided apart in both the tunnel circumferential direction and the axial direction.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a tunnel ring. FIG. 2 shows an A-shaped segment. (A) is a sectional side view, (B) is a bottom view. FIG. 2 is a cross-sectional view of the knee line of FIG. 2. FIG. 5 is a front view showing a circumferential end surface of the A-type segment. FIG. 6 is a B-type segment, (A) is a cross-sectional side view, and (B) is a bottom view. FIG. 7 shows a K-shaped segment, (A) is a cross-sectional side view, (B) is a bottom view. FIG. 8 shows a segment of another structure, (A) is a cross-sectional side view, and (B) is an enlarged view of the main part. Sectional view [Explanation of symbols]
1a Arc-shaped plate part 1b End face plate part 1c Curved plate part 1f Rib part 14 Thick part

Claims (2)

A tunnel segment for forming a tunnel inner wall by connecting a large number in the circumferential direction of the tunnel and in the tunnel axial direction,
While forming a curved plate portion that forms the outer periphery of the tunnel, a pair of arc-shaped plate portions at both ends in the tunnel axial direction, and a pair of end face plate portions at both ends in the tunnel circumferential direction, it is configured as a metal one. the intermediate portion of the tunnel circumferential direction of the curved plate portion, the thick portion capable of forming a grout injection holes, forms the shape such that the thickness than the surrounding in larger circular region than the diameter of the through hole Tunnel segment.   It is made of cast iron having a rib portion extending in the tunnel axis direction in a state extending between the pair of arcuate plate portions. The tunnel segment according to claim 1, which is formed between the parts.

Images