JP2009024495A - Concrete filled steel segment and primary lining body for tunnel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a concrete filled steel segment excellent in economical efficiency reducing bending moment generated from the own weight of the segment by reducing the own weight of the segment. <P>SOLUTION: The concrete filled steel segment used as a primary lining body of a tunnel constructed by a shield tunneling method is constituted by filling concrete inside a steel shell and is comprised of at least two outer main girders 5a, two middle main girders 5b, a vertical rib 16c for connecting the middle main girders 5b, reinforced plates 21 for connecting the outer main girders 5a and the middle main girders 5b, joint plates 6 and a skin plate 7. Further, a closed space 23 for preventing the inflow of the inside filling concrete 4 is formed by blocking with a lid plate 22 between the two middle main girders 5a. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a concrete-filled steel segment configured by filling concrete into a steel-based segment structure used as a primary lining body such as a shield tunnel.

  Conventionally, a primary lining body in a tunnel is configured by connecting a plurality of segments 1 in the tunnel circumferential direction to form a segment ring 2 and connecting the segment rings in the tunnel axial direction as shown in FIG. . Types of segment 1 include those comprising a standard steel shell having a steel main girder, a steel shell having a main girder filled with concrete, or a corrugated spheroidal graphite shell. There are known concrete fillings inside the tunnel's interior and tunnel ground.

  FIG. 7 shows a steel segment 1 in which concrete 4 is packed inside a cast steel shell 3 as a first conventional example. In the segment 1, a pair of main girders 5 are arranged in parallel, and both end portions of the left and right main girders 5 are connected by a joint plate 6, and a rectangular shape assembled by the main girders 5 and the joint plate 6. A skin plate 7 is welded to the outer end surface of the segment frame, and a plurality of reinforcing vertical ribs 8 are disposed between the left and right main girders 5 at predetermined intervals in the circumferential direction of the tunnel. The steel shell 3 is constituted by being fixed by welding. Filled concrete 4 is filled into the steel shell 3.

  The joint plate 6 is provided with a plurality of bolt holes 10 for bolting the steel segments 1 in the tunnel circumferential direction, and the main girder 5 is bolt holes for joining the segment rings in the tunnel axial direction. 10 have been established. In addition, at the inner center position of the steel segment 1, a hanging metal fitting 11 for lifting the shield machine with the erector device of the shield machine at the time of assembling the segment is welded to the inner surface of the vertical rib 8 and the skin plate 7. A grout injection hole 12 is provided for penetrating through the gap between the back surface of the segment ring and the natural ground.

  In the steel segment 1, various improvements have been made to the structure of the steel shell 3 in order to increase the rigidity against twisting and bending moments acting on the steel segment 1 without increasing its own weight as much as possible. For example, as shown in FIG. 7, an arcuate portion 13 is formed at the edge of the vertical rib 8 on the air side in the tunnel, or as the second conventional example, the air side in the tunnel of the vertical rib 8 as in the segment 1 shown in FIG. The segment strength is improved by forming the T-shaped portion 14 at the end edge of the.

Further, in the concrete-filled steel segment 1, the fill-in concrete 4 contributes to the improvement of the strength of the steel segment 1, and the fill-in concrete 4 eliminates the need for a secondary lining on the inner side of the segment. There is also an effect of tightening. In the concrete-filled steel segment 1, the box joints for segment joints and ring joints (with a box part) are usually used for any steel shell with 2 to 4 main girders (some are three). Except in some cases, the inside of the steel shell 3 is filled with solid filling concrete without gaps.
JP 2003-27894 A JP 2002-121999 A JP 2000-34897 A

  As a means of improving the strength of the concrete-filled steel segment, a device has been devised to improve the strength against buckling strength and bending moment by devising the shape of vertical ribs and the like. The segment strength can also be improved by filling the steel shell with solid filling concrete. However, the means for improving the strength of the steel segment by filling the inside-filled concrete faces another problem that the weight of the segment itself increases more than necessary.

  9 (a), (b), (c) are schematic diagrams showing the magnitude of the bending moment acting on the segment ring from the 360 ° direction when the secondary lining body is constructed with steel segments. (A) shows the bending moment due to its own weight, (b) shows the bending moment due to the external load, (c) shows the bending moment for design calculated based on the above (a) and (b), In consideration of (c), the concrete-filled steel segment is constructed. However, when the strength of the segment is improved by filling the concrete to satisfy this condition, another problem that the weight of the segment increases occurs. There is a bug.

  Specifically, when a concrete-filled steel segment with solid concrete filled inside a steel shell is used as the primary lining body of a large-diameter shield tunnel with an outer diameter of the segment ring exceeding 10 m. Compared with the segment for small and medium-diameter shield tunnels, the bending moment generated by the segment's own weight is greatly increased, rather than resisting the cross-sectional force (bending moment, axial force, shearing force) due to soil water pressure acting after service. There is a problem that the cross-section for resisting the cross-sectional force due to its own weight becomes large, resulting in a very uneconomic segment.

  Due to such a large bending moment generated by its own weight, the segment height of the reinforced concrete segment for a large-diameter shield tunnel reaches 500 to 600 mm.

  For example, in the case of a shield tunnel with an outer diameter of 5 m, the bending moment due to its own weight was about 30% of the total bending moment including the bending moment due to soil water pressure, whereas in the case of a shield tunnel with an outer diameter of 12 m. In this situation, 80% of the total bending moment is generated by the weight of the segment.

  The present invention reduces the segment self-weight by configuring a closed space in which the steel shell is not filled with concrete, reduces the bending moment generated by the segment self-weight, The purpose is to provide a concrete-filled steel segment with excellent economic efficiency.

  In addition, the present invention provides a concrete-filled steel segment that is excellent in fire resistance or corrosion resistance and eliminates the need for secondary lining by placing concrete in the tunnel inside the steel shell. Objective.

  In order to achieve the above object, the concrete-filled steel segment of the present invention is configured as follows.

The concrete-filled steel segment of the first invention is a concrete-filled steel segment constructed by filling concrete into a steel shell used as a primary lining body of a tunnel constructed by a shield method, It consists of at least two outer main girders and two middle main girders, vertical ribs that connect the middle main girders, and reinforcing plates, joint plates, and skin plates that connect the outer main girders and the middle main girders. A closed space is formed by closing the space with a cover plate to prevent the inflow of the filled concrete.

  According to a second aspect of the present invention, in the concrete-filled steel segment according to the first aspect of the invention, a web member that connects the middle main girder, the skin plate, and the main girder is provided.

  According to a third aspect of the present invention, in the concrete-filled steel segment of the first or second aspect, the shape of the vertical rib arranged between the two middle main girders is a flat plate shape, an L shape, a T shape, a substantially rectangular shape, or a substantially circular shape. It is a shape.

  The fourth invention is a steel-filled steel segment according to any one of the first to third inventions, wherein one or more of structural steel, cast steel, spheroidal graphite cast iron is used as the steel material constituting the steel shell. It is characterized by using.

  According to a fifth aspect of the present invention, in the concrete-filled steel segment according to any one of the first to fourth aspects, the longitudinal rib or cover plate connecting the two main main girders is made of synthetic resin and / or fiber reinforced plastic. Features.

  According to a sixth invention, in the concrete-filled steel segment according to any one of the first to fifth inventions, ordinary concrete or lightweight concrete is used as the fill concrete.

  7th invention uses the concrete which provided any one or more of fire resistance, acid resistance, and sulfate resistance as filling concrete in the concrete filling steel segment of 1st-6th invention. It is characterized by.

The primary lining body of the tunnel of the eighth invention is characterized in that it is constructed using any of the concrete filled steel segments of the concrete filled steel segments of the first to seventh inventions.

  The concrete filled steel segment according to the present invention has a great feature that it can provide an economical concrete filled steel segment that is lighter in weight than a conventional concrete filled steel segment.

  That is, a concrete-filled steel segment constructed by filling concrete into a steel shell used as a primary lining body of a tunnel constructed by a shield method, comprising at least two outer main girders and two middle The main girder is composed of a longitudinal rib that connects the middle main girder, and a reinforcing plate that connects the outer main girder and the middle main girder, a joint plate, and a skin plate. By forming a closed space that prevents the inflow of filled concrete, the unit capacity weight as a segment can be reduced. As described above, according to the present invention, the bending moment generated by the segment's own weight is reduced, and further, with respect to the large bending moment acting on the longitudinal rib, the cover plate and the skin plate that connect the two main main girders, it is economical. It is possible to respond. Furthermore, if sufficient “covering” concrete is provided on the inner space side of the segment, it is possible to provide necessary fire resistance or corrosion resistance performance in a road tunnel or the like.

  In addition, if further weight reduction is required, it is possible to use lightweight concrete as filling concrete, and it is also necessary when performance such as fire resistance, acid resistance, and sulfate resistance is required. It is possible to provide a concrete-filled steel segment that satisfies the required performance by filling special concrete with special properties.

  In particular, when expensive special concrete is used, it is possible to further improve the economic efficiency by using special concrete only for the cover portion and using ordinary concrete for the other portions.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected and demonstrated to the same element as the past.

  FIGS. 1 and 2 (a) show a concrete-filled steel segment 15 according to a first reference embodiment, in which a pair of main girders 5 are arranged in parallel, and between both ends of the left and right main girders 5 are joint plates. 6, a skin plate 7 is welded to the outer end surface of a rectangular segment frame formed by the main girder 5 and the joint plate 6, and between the left and right main girder 5, the tunnel circumferential direction is predetermined. A plurality of reinforcing vertical ribs 16 are disposed with a gap therebetween, and both ends thereof are fixed by welding to form a steel shell 17. Filled concrete 4 is filled into the steel shell 17.

  In the segment 15 of the first reference embodiment, the reinforcing vertical ribs 16 are formed of hollow circular steel pipes, and both end portions of the vertical ribs 16 are welded so that no gaps are formed on the side surfaces of the main beam 5. There is a feature in the point. Therefore, when the inside concrete 4 is filled in the steel shell 17, the inflow of the inside concrete 4 into the hollow portion 9 of the reinforcing vertical rib 16 is prevented, and the amount of concrete used is reduced accordingly, and the segment 15 Is reduced in weight.

  FIG. 2 (b) shows the concrete-filled steel segment 15 according to the second reference embodiment, and the point that the reinforcing vertical rib 16a is formed of a hollow rectangular steel pipe is different from the first reference embodiment. The configuration is the same as in the first embodiment. Also in the second embodiment, when the inside concrete 4 is filled into the steel shell 17, the inflow of the inside concrete 4 is prevented from flowing into the hollow portions of the reinforcing vertical ribs 16a, and the amount of concrete used is reduced accordingly. And the weight of the segment 15 is reduced.

  FIG.2 (c) shows the concrete filling steel segment 15 which concerns on 3rd reference form, and the cross-sectional view of the direction perpendicular to a longitudinal direction is comprised with the substantially U-shaped steel material in the reinforcement vertical rib 16b, The first and second embodiments are that the U-shaped opening 18 is in close contact with the inner surface of the skin plate 7 and is fixed by fillet welding 19, and both end portions are fixed to the side surfaces of the main girder 5. Unlike the first embodiment, the other configurations are the same as those of the first and second reference embodiments. Also in the third reference form, when the inside concrete 4 is filled in the steel shell 17, the inside concrete 4 is prevented from flowing into the hollow portion of the reinforcing vertical rib 16b, and the amount of concrete used is reduced accordingly. And the weight of the segment 15 is reduced. The cross-sectional shape of the reinforcing vertical rib may be an oval or other shape as long as it has a hollow portion inside.

  As described above, according to the first to third reference embodiments, the longitudinal ribs 16, 16 a, 16 b that are one element constituting the steel shell 17 are constituted by hollow members, and the filling concrete 4 flows into the hollow portion 9. Thus, the weight reduction of the concrete-filled steel segment 15 is realized.

3 to 5 show the concrete-filled steel segment 15 according to the first embodiment.
In the first embodiment, the gap between the members constituting the steel shell 17 is closed to form a closed space for preventing the filling of the filling concrete inside, thereby reducing the weight of the concrete filling steel segment 15. It has been realized.

  More specifically, in the concrete-filled steel segment 15, two outer main girders 5 a and two middle main girders 5 b are arranged in parallel, and the joint plate 6 is between both ends of the inner and outer main girders 5 a and 5 b. The skin plate 7 is welded to the outer end surface of the rectangular segment frame assembled by the main girders 5 a and 5 b and the joint plate 6. Between the left and right middle main girders 5b, a plurality of vertical ribs 16c each having an arcuate portion 20 formed at the inner edge are provided at predetermined intervals in the segment longitudinal direction. Reinforcing plates (web members) 21 are disposed between the girders 5a and the middle main girder 5b at substantially the same intervals as the vertical ribs 16c. By forming an arcuate portion 20 at the inner end of the vertical rib 16c, the buckling strength and rigidity are improved. The shape of the vertical rib 16c may be any shape such as a flat plate shape, an L shape, a T shape, or a substantially rectangular shape.

  Further, a cover plate 22 is disposed across the inner edge of the two middle main girders 5b and fixed by welding. The lid plate 22 extends the entire length in the longitudinal direction of the middle main girder 5 b, and a closed space 23 is formed at a portion surrounded by the lid plate 22, the left and right middle main girder 5 b, and the skin plate 7. Therefore, the filling concrete 4 filled in the steel shell 17 is filled so as to fill the gap between the left and right outer main girders 5a and the middle main girders 5b, and in the closed space 23 closed by the cover plate 22. Is not filled. In addition, the filling concrete 4 functions as a secondary lining that provides fire resistance, corrosion resistance, etc. in addition to improving the strength of the segment housing. For this reason, the filling concrete 4 is provided on the entire inner surface of the segment. It is filled so as to cover. That is, a part of the filling concrete 4 is attached to the surface of the cover plate 22 with a predetermined thickness, and is thus filled so that the entire inner surface of the segment 15 forms a flat surface 24.

  As described above, according to the first embodiment, the closed space 23 is formed in the segment steel shell 3 at the portion surrounded by the cover plate 22, the left and right middle main girders 5 b and the skin plate 7. Since the filling concrete 4 is prevented from flowing in, the weight of the concrete filling steel segment 15 is reduced.

In the reference form and the embodiment of the present invention, each part of the segment can be configured as follows. (1) As the steel material constituting the steel shell 17, any one or more of structural steel, cast steel, and spheroidal graphite cast iron can be used. (2) In the segment 15 of the first embodiment, the cover plate 22 and the reinforcing vertical ribs 16c connecting the two middle main beams 5b may be made of synthetic resin or fiber reinforced plastic. This can further reduce the weight. (3) Ordinary concrete or lightweight concrete may be used as the filling concrete 4. (4) Furthermore, as the filling concrete 4, concrete imparted with any one or more of fire resistance, acid resistance, and sulfate resistance can be used. (5) A primary lining body can be constructed using the segments 15 of the first to third reference embodiments or the first embodiment. (6) In this primary lining body, the segment self-weight is reduced by using the segment 15 of the 1st-3rd reference form or 1st Embodiment. (7) The segment and the primary lining body can be manufactured based on the design of strength and weight reduction using an intended design method.

It is a perspective view of the steel shell of the concrete inside-packed steel segment which concerns on a 1st reference form. (A) is a cross-sectional view of a segment in which the steel shell of FIG. 1 is filled with filled concrete, (b) is a cross-sectional view of the segment according to the second reference form, and (c) is a cross-sectional view of the segment according to the third reference form. It is sectional drawing. It is a perspective view which fractures | ruptures and shows the segment made from concrete filling steel which concerns on 1st Embodiment. (A) is AA reference sectional drawing of FIG. 3, (b) is BB sectional drawing of FIG. (A) is CC sectional drawing of FIG. 3, (b) is the DD arrow directional view of FIG. It is a perspective view of the segment ring constructed | assembled with the concrete filling segment. (A) is the perspective view of the steel shell in the concrete filling segment of the 1st example conventional concrete, (b) is sectional drawing which filled the filling concrete in the steel shell of figure (a). It is sectional drawing of the concrete filling segment of the 2nd prior art example. (A), (b), (c) is a schematic diagram showing a bending moment due to its own weight acting on each segment ring, a bending moment due to an external load, and a design bending moment.

Explanation of symbols

1 Segment 2 Segment Ring 3 Steel Shell 4 Filled Concrete 5 Main Girder 5a Outer Main Girder 5b Middle Main Girder 6 Joint Plate
DESCRIPTION OF SYMBOLS 7 Skin plate 8 Vertical rib 9 Hollow part 10 Bolt hole 11 Suspension metal fitting 12 Grout injection hole 13 Arc-shaped part 14 T-shaped part 15 Concrete filling steel segment 16 Reinforcement vertical rib 17 Steel shell 18 Opening 19 Fillet Welding 20 Arc-shaped part 21 Reinforcement plate (web member)
22 Lid plate 23 Closed space
24 flat surface

Claims (8)

  A concrete-filled steel segment constructed by filling concrete into a steel shell used as the primary lining body of a tunnel constructed by the shield method, with at least two outer main girders and two middle main girders , Composed of a vertical rib that connects the middle main girder, a reinforcing plate that connects the outer main girder and the middle main girder, a joint plate, and a skin plate. A concrete-filled steel segment characterized by a closed space that prevents the inflow of concrete.   2. The concrete-filled steel segment according to claim 1, further comprising a web member that connects the middle main girder to the skin plate and the main girder.   The shape of a vertical rib arranged between two middle main girders is flat plate shape, L shape, T shape, substantially rectangular shape, or substantially circular shape, The concrete filling steel according to claim 1 or 2 Made segment.   The concrete-filled steel according to any one of claims 1 to 3, wherein any one or more of structural steel, cast steel, and spheroidal graphite cast iron is used as the steel material constituting the steel shell. Made segment. The concrete-filled steel segment according to any one of claims 1 to 4, wherein the longitudinal ribs or cover plates connecting the two middle main girders are made of synthetic resin and / or fiber reinforced plastic. The concrete-filled steel segment according to any one of claims 1 to 5, wherein ordinary concrete or light-weight concrete is used as the filling concrete. The concrete-filled steel according to any one of claims 1 to 5, wherein concrete filled with any one or more of fire resistance, acid resistance, and sulfate resistance is used as the filling concrete. Made segment. A primary lining body of a tunnel constructed using the concrete-filled steel segment according to any one of claims 1 to 7.

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