JP4161344B2 - Steel shell joint structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a steel shell joint structure for joining adjacent steel shells.
[0002]
[Prior art]
As a method of constructing a tunnel with a large cross-section, the tunnel outer shell is pre-excavated with multiple shield machines, and then the tunnel outer shell is built by connecting the excavated single tunnels together. There is a method of constructing a tunnel with a large section by excavating the earth and sand in the outer shell.
This construction method will be described with reference to FIG. First, after the construction of the shaft, a shield machine is dug to construct a single tunnel 31 that constitutes an outer shell portion that becomes a tunnel housing (FIG. 8A). Next, after the construction of the adjacent single tunnel 31 is completed, a part of the steel shell constituting the single tunnel is removed, and the single tunnel connection portion 32 is constructed (FIG. 8B).
Then, the concrete 33 is placed in the steel shell to construct the outer shell housing 34 (FIG. 8C). Finally, a large cross-section tunnel is constructed by excavating the inner earth and sand 35 with an excavating machine (FIG. 8D).
[0003]
In the tunnel having a large cross section constructed as described above, each single tunnel 31 has a combined structure of a steel shell and concrete, or a steel shell and reinforced concrete, and has sufficient strength. On the other hand, since each single tunnel connection part 32 does not have a steel shell or the like, the cross-section has a low strength as it is.
Further, in the single tunnel connecting portion 32, the excavation error at the time of excavation of each single tunnel is combined to generate a three-dimensional relative error. For this reason, in the joining method such as the commonly used welding joining and friction joining using the attachment plate, there are problems that it is difficult in construction and the required strength is insufficient.
[0004]
As a solution to this problem, for example, there is a segment joint structure disclosed in Patent Document 1. FIG. 9 is a cross-sectional view of the segment joint structure disclosed in Patent Document 1, and FIG. 10 is an enlarged view of the main part thereof. The segment joint structure shown in Patent Document 1 will be described with reference to FIGS.
[0005]
What was disclosed by patent document 1 joins between the edge parts of the steel segments 41 adjacent to the circumferential direction of a large section tunnel with the segment joining metal fitting 42. FIG.
And the segment joining metal fitting 42 is spanned between the edge part of steel segments 41 and 41, Comprising: The edge part is formed in the cross beam 41b located in the edge part of the circumferential direction of the steel segment 41 43 are respectively attached to both ends of the long bolt 42a in order, and in cooperation with each other, the end of the long bolt 42a is arranged in an arbitrary direction with respect to the cross beam 41b. A receiving washer 42b and an abutting washer 42c that can be freely rotated are screwed into both ends of the long bolt 42a from the rear of the abutting washer 42c, and the end of the long bolt 42a is joined to the cross beam 41b. The fixing nut 42d is fixed.
[0006]
A concave curved surface portion is formed at the contact portion between the receiving washer 42b and the contact washer 42c. On the other hand, a convex curved surface portion is formed at the abutting portion of the abutting washer 42c with the receiving washer 42b so that it can slide freely within the concave curved surface portion.
[0007]
Since the steel segments 41 and 41 are joined together by the segment joint fitting 42 as described above, the three-dimensional relative error between the steel segments 41 can be easily absorbed and the steel segments 41 can be easily joined. It can be joined to.
[0008]
[Patent Document 1]
Japanese Patent Laid-Open No. 09-296693
[Problems to be solved by the invention]
In the prior art, it is called a segment or a steel segment, but in the present invention, it is hereinafter called a steel shell. In Patent Document 1 configured as described above, the pulling force of the joint portion between each single tunnel is mainly borne by the long bolt 42a installed across the steel shells (steel segments) constituting each single tunnel. Will do. Therefore, it is necessary to reliably transmit the tensile force acting on the long bolt 42a to the steel shell 41, and it is necessary to firmly fasten the steel shell 41 and the long bolt 42a.
On the other hand, the structure must be able to absorb the three-dimensional relative error between the steel shells 41.
Thus, it is necessary to satisfy the two requirements of firmly fastening the long bolt 42a and the steel shell 41 and absorbing a three-dimensional relative error.
And in the said patent document 1, as a structure which satisfy | fills this request | requirement, using the receiving washer 42b which has a concave curved surface part, the contact washer 42c which has the convex curved surface part which slides the inside of a concave curved surface part freely, and the fixing nut 42d, The structure of mechanically fastening is adopted.
[0010]
However, the steel shell joint structure disclosed in Patent Document 1 is configured to be mechanically fastened, and thus has a receiving washer 42b having a concave curved surface portion and a convex curved surface portion that slides freely within the concave curved surface portion. Since the contact washer 42c is required and special processing is required to manufacture these, there is a problem that the manufacturing cost is increased.
[0011]
The present invention has been made in order to solve such a problem, and does not require a special processing member, and absorbs a three-dimensional construction error so that the steel shells can be securely and easily joined to each other. An object of the present invention is to provide a joint structure.
[0012]
[Means for Solving the Problems]
The steel shell joint structure according to the present invention is a steel shell joint structure in which steel bars are placed between steel shells adjacent in the circumferential direction of the tunnel and concrete is placed between them to join the steel shells together.
Fixed to the insertion hole provided in the end plate of the adjacent steel shell, the steel bar inserted into the insertion hole so as to be movable in three dimensions, and the end on the insertion side of the steel bar And a bearing plate that transmits the tensile force acting on the steel bar to the end plate through the concrete ,
The insertion hole is a long hole through which a plurality of steel bars can be inserted.
[0013]
In addition, in the steel shell joint structure where steel rods are passed between steel shells adjacent in the tunnel circumferential direction and concrete is placed between them to join the steel shells together,
At the end of the main girder forming the adjacent steel shell,
An end plate supported immovably on the end side by the reinforcing plate;
An insertion hole provided in the end plate;
Steel bars each having both ends inserted through the insertion holes so as to be three-dimensionally movable,
And a bearing plate that is fixed to the end of the steel bar on the insertion side and transmits a tensile force acting on the steel bar through the concrete to the end plate.
Furthermore, the insertion hole is a long hole into which a plurality of steel bars can be inserted.
[0014]
In addition, each steel bar is obtained by joining two steel bars after passing through the end plates of adjacent steel shells.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
1 is a plan view of a steel shell joint structure according to an embodiment of the present invention, FIG. 2 is a partial cross-sectional view of FIG. 1, FIG. 3 is a cross-sectional view taken along line AA in FIG. 2 is a sectional view taken along the line BB in FIG. 2, and FIG. 5 is a sectional view taken along the line CC in FIG.
[0016]
The configuration of the present embodiment will be described with reference to FIGS. In FIG. 1, reference numeral 1 denotes a part of adjacent steel shells separated by a predetermined interval, and these adjacent steel shells 1 are joined by a joint structure 3.
First, the steel shell 1 constituting the single tunnel will be described. The steel shell 1 includes a plate-like main girder 5 arranged at a predetermined interval in the circumferential direction of the tunnel, a plurality of vertical ribs 7 arranged at a predetermined interval in the direction perpendicular to the main girder 5, and a main girder 5 and a vertical rib. 7 is provided with a skin plate 9 fixed to the bottom surface of the frame constituted by 7 and an end plate 11 installed at each opposing end of the adjacent steel shell 1.
[0017]
The end plate 11 is provided with a later-described screw rebar 15 and an opening 11a having a margin that allows the inserted screw rebar 15 to move three-dimensionally (see FIG. 4).
Here, the attachment structure of the end plate 11 will be described. A plurality of reinforcing plates 12 are welded to the end portions of the main girder 5, and a peripheral edge portion on one side of the end plate 11 is brought into contact with the end surfaces of the reinforcing plates 12. In other words, the end plate 11 is not fixed to the main beam 5 but is attached to the main beam 5 by preventing the end plate 11 from moving toward the end of the steel shell 1 by contacting the reinforcing plate 12. Yes.
[0018]
Next, the joint structure 3 for joining the steel shells installed at a predetermined interval will be described.
The joint structure 3 according to the present embodiment includes a plurality of screw rebars 15 inserted into opening portions 11 a provided in opposing end plates 11 of adjacent steel shells 1, and a double fixing nut at the insertion end of each screw rebar 15. The bearing plate 19 fixed by 17, the end plate 11, the reinforcing plate 12, and the hoop bars 14, each steel shell 1 is filled with concrete 16, and the screw rebar 15 and the steel shell 1 are filled with concrete. Via pressure bearing.
[0019]
With the structure as described above, since the screw rebar 15 is inserted through the opening 11a and can be moved three-dimensionally, it is assumed that there is a three-dimensional error between the individual tunnels when joining the single tunnels. Also, adjacent steel shells 1 can be connected. The screw rebar 15 and the steel shell 1 are securely supported and joined by the filled concrete 16.
[0020]
The concrete 16 between the bearing plate 19 and the end plate 11 receives a local strong compressive force when a tensile force is applied to the screw rebar 15, and a tensile stress acts in a direction perpendicular to the direction in which the compressive force acts. There is. Therefore, in the present embodiment, the hoop bar 14 is disposed between the bearing plate 19 and the end plate 11 so as to resist the tensile force by the hoop bar 14, so that the concrete 16 is cracked. Can be prevented.
[0021]
In addition, although the screw rebar 15 of said example showed what straddled both the steel shells 1 to join, this invention is not restricted to this, What connects in the middle what was divided | segmented into two It may be.
In the above example, the screw rebar 15 is arranged in two stages. However, as shown in FIG. 6, the opening 11a may be a long hole and may be arranged in one stage.
[0022]
FIG. 7 is an explanatory view of a joining procedure for the one-stage type joining structure shown in FIG. 6, and shows a state in which the steel shell 1 is viewed from the side cross-sectional direction (the same direction as FIG. 3). In addition, what was shown in FIG. 7 is a type which connects two screw rebars on the way. Hereinafter, the joining method of the steel shell 1 will be described with reference to FIG.
[0023]
First, the formwork plate 21 is installed between the adjacent steel shells 1, and the earth and sand between the steel shells 1 are removed. And the screw rebar 15 is each inserted in the opening part 11a provided in the end plate 11 of each steel shell 1 (Fig.7 (a)).
After inserting the screw rebar 15, one end of each screw rebar 15 is connected using the joining member 23. At this time, since each screw rebar 15 can be moved three-dimensionally within the opening 11a, even if each steel shell 1 has a three-dimensional positional error, both can be joined.
After connecting each screw rebar 15, the exposed length L of each screw rebar 15 (the length from the end plate 11 to the insertion-side end of the screw rebar 15) L is adjusted, and this exposed length L is placed in the concrete placement. In order to prevent the change from time to time, the end plate 11 is fixed to one or both of the end plates 11 by means of, for example, screw reinforcement 15 tack welding (FIG. 7B).
[0024]
After that, a bearing plate 19 of a predetermined size is fixed to both ends of the screw rebar 15 by holding it from both sides with a double fixing nut 17 (FIG. 7C), and the connection portion between the steel shell 1 and the single tunnel. Concrete 27 is placed on 25 (FIG. 7D).
Here, the pressure bearing plate having a predetermined size is a pressure bearing plate having a size necessary for reliably transmitting the tensile force to the end plate 11 when a tensile force acts on the screw rebar 15.
[0025]
If the concrete 27 hardens | cures, the steel shells 1 will be integrated and the sufficient intensity | strength will be hold | maintained. That is, it is possible to realize a reinforced concrete structure in which the screw rebar 15 that resists tensile force resists tensile force and the concrete 27 that resists compressive force resists compressive force.
In order to resist the screw rebar 15 when a tensile force is applied, it is necessary to reliably transmit the force from the screw rebar 15 to the steel shell 1. In this respect, in this embodiment, the screw rebar is used. The force 15 is loaded evenly on the end plate 11 through the support pressure of the concrete sandwiched between the support plate 19 and the end plate 11. Since the end plate 11 is supported by the reinforcing plate 20 welded to the main girder 5, the force from the screw rebar 15 is reliably transmitted to the main girder 5 of the steel shell 1.
The end plate 11 is cut off from the main girder 5 and has a structure that does not transmit bending to the main girder 5.
[0026]
As described above, according to the present embodiment, the three-dimensional error between the adjacent steel shells 1 can be absorbed while the complicated workpiece required in the prior art is unnecessary, and the adjacent steel shells 1 are absorbed. Can be reliably joined.
Moreover, in this Embodiment, since the rectangular or elongate opening part 11a was provided as an insertion hole which penetrates the screw rebar 15, the screw rebar 15 can be inserted easily and workability | operativity is good.
Further, since the screw rebar 15 is inserted through the opening 11a provided in the end plate 11, the screw rebar can be positioned in the vicinity of the outer side of the tunnel cross section, so that it effectively functions against a bending moment acting on the tunnel cross section. .
[0027]
However, the insertion hole in the present invention is not limited to a rectangular shape or a long hole shape, and when the screw rebar 15 is inserted, the screw rebar 15 is moved back and forth and left and right, and the three-dimensional position between the steel shells is changed. Any device that can afford to absorb the error may be used.
[0028]
Moreover, in this Embodiment, since the structure which inserts the two screw rebars 15 in each adjacent steel shell 1, and joins this was employ | adopted, the vertical rib 7 in the steel shell 1 becomes obstructive, and a screw rebar. 15 can be applied even when it cannot be inserted deeply into one steel shell 1.
[0029]
In the above-described embodiment, the screw rebar is taken as an example of the steel bar. However, the present invention is not limited to this, and any steel bar that can bear a tensile force may be used.
[0030]
【The invention's effect】
In the present invention, an insertion hole provided in an end plate of an adjacent steel shell, a steel bar member whose both ends are inserted into the insertion hole so as to be three-dimensionally movable, and an insertion side of the steel bar member It is equipped with a bearing plate that is fixed to the end and transmits the tensile force acting on the steel bar to the end plate via concrete, so that no complicated work is required, but the tertiary between adjacent steel shells. The original error can be absorbed and adjacent steel shells can be reliably joined together.
[Brief description of the drawings]
FIG. 1 is a plan view of an embodiment of the present invention.
FIG. 2 is a partial plan sectional view of FIG. 1;
3 is a cross-sectional view taken along the line AA in FIG. 2;
4 is a cross-sectional view taken along the line BB in FIG.
5 is a cross-sectional view taken along the line CC in FIG.
FIG. 6 is an explanatory diagram of another aspect of the opening in one embodiment of the present invention.
FIG. 7 is an explanatory diagram of a construction procedure for a joint structure according to an embodiment of the present invention.
FIG. 8 is an explanatory diagram of a process for constructing a large-section tunnel.
FIG. 9 is a plan view of a conventional example.
FIG. 10 is an explanatory diagram of a main part of a conventional example.
[Explanation of symbols]
1 Steel Shell 3 Joint Structure 11 End Plate 11a Opening 15 Screw Reinforcement 19 Bearing Plate

Claims (4)

In the steel shell joint structure where steel rods are passed between steel shells adjacent in the circumferential direction of the tunnel and concrete is placed between them to join the steel shells together.
Fixed to the insertion hole provided in the end plate of the adjacent steel shell, the steel bar inserted into the insertion hole so as to be movable in three dimensions, and the end on the insertion side of the steel bar And a bearing plate that transmits the tensile force acting on the steel bar to the end plate through the concrete ,
A steel shell joint structure, wherein the insertion hole is a long hole into which a plurality of steel bars can be inserted . In the steel shell joint structure where steel rods are passed between steel shells adjacent in the circumferential direction of the tunnel and concrete is placed between them to join the steel shells together.
At the end of the main girder forming the adjacent steel shell,
An end plate supported immovably on the end side by the reinforcing plate;
An insertion hole provided in the end plate;
Steel bars each having both ends inserted through the insertion holes so as to be three-dimensionally movable,
A steel shell joint comprising: a support plate that is fixed to an end of the steel bar on the insertion side and transmits a tensile force acting on the steel bar to the end plate via concrete. Construction.   The steel shell joint structure according to claim 2, wherein the insertion hole is a long hole through which a plurality of steel bars can be inserted. 4. The steel shell joint according to claim 1 , wherein each steel bar is obtained by joining two steel bars after being inserted into end plates of adjacent steel shells, respectively. Construction.

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