JP7076215B2 - Fixing structure of fittings - Google Patents

Description

In the present invention, a male joint metal fitting fixed to the main girder on one side of a segment which is an outer shell lining of a shield tunnel and a female joint metal fitting fixed to the main girder on the other side are fitted to each other. Of the ring joint structures of the segments that join both segments together, the structure relating to the fixing structure of the female joint fitting to the main girder.

In recent years, in shield construction, labor saving in segment fastening work and cost reduction by shortening the construction period have become issues, and instead of the conventional segment fastening with bolts and nuts, so-called one-pass joints that can be fastened with one touch suitable for automatic construction. Development has been carried out by manufacturers.
Of these one-pass joints, for fastening in the circumferential direction of the segment (hereinafter abbreviated as "segment joint"), a slide type fitting joint that completes the fastening of the joint by sliding the segment in the direction of the tunnel ring axis is used. For fastening between segment rings (hereinafter abbreviated as "ring joint"), a convex male joint fitting provided in one segment and a concave female joint fitting provided in the other segment are used. Pin-insertion type fitting joints, which complete the fastening of the joint by inserting it in the direction of the tunnel axis, are the mainstream.

Until now, one-pass joints have been widely used in inexpensive RC segment (reinforced concrete segment) sections, especially in large-diameter long-distance shield construction where high-speed construction is required. However, with the recent congestion of structures in urban areas, there are an increasing number of cases where construction is unavoidable at shallow depths with partially soft ground, even if it is disadvantageous in terms of earthquake resistance. The synthetic segment is growing its performance.
Since the synthetic segment can be evaluated on the premise that concrete is filled inside the steel shell and the steel shell and concrete behave integrally with external force, the segment has higher rigidity than the general RC segment. It enables high yield strength.

In order to apply a one-pass joint to a synthetic segment, a through hole for fitting the joints to each other must be provided in the joint plate in the case of a segment joint and in the main girder in the case of a ring joint. That is, in the arrangement of the one-pass joint, in the case of the RC segment, the joint end face may be arranged according to the joint surface of the segment, but in the case of the synthetic segment (including the steel segment), the thickness of the joint plate and the main girder may be adjusted. Consideration must be considered for placement.
Of the one-pass joints, for ring joints, in addition to external loads such as earth pressure and water pressure that act in the direction of the tunnel cross section, shear force and tensile force that act between each tunnel ring in order to respond to response displacement during an earthquake. It is required to have a predetermined strength against a force as its performance.

Patent Document 1 discloses a structure for fixing a female joint fitting (cylinder) to a main girder (end face plate C1 of a segment) in a ring joint of a steel segment.
Further, Patent Document 2 discloses a fixing structure in which the end face of the female joint fitting (female joint fitting 3) is fixed to the main girder in a state of being inserted so as to match the joint surface of the main girder. ..

Japanese Unexamined Patent Publication No. 2009-203684 Japanese Unexamined Patent Publication No. 2016-61038

In the fixing structure of the female joint fitting in Patent Document 1, the insertion length of the male joint fitting into the female joint fitting changes depending on the thickness of the main girder to which the female joint fitting is fixed. It will be necessary to change the length and diameter of the male joint fitting according to the thickness of the main girder. Therefore, when multiple main girder thicknesses are adopted for each tunnel section, it is necessary to consider changing the female joint fitting for each thickness.
Further, since the female joint fitting of Patent Document 1 is fixed via the steel plates 24 and 25 welded to the back surface side of the main girder, even if a tensile force for pulling out the fitted male joint fitting acts. , The tensile force is directly transmitted to the main girder to which the female joint fitting is fixed, but the shearing force is transmitted to the main girder through the welding of the steel plates 24 and 25, so that the required shear strength is met. Securing the welding length and high quality for welding are required.
On the other hand, in the fixed structure of the female joint fitting in Patent Document 2, since a part of the female joint fitting is inserted through the main girder, the shear external force is directly transmitted to the main girder, but the tensile force is not satisfied. , It must be resisted by welding the female joint fitting to the back of the main girder or fixing it to the filled concrete.
When expecting a predetermined shear load for welding to the back surface of the main girder of female joint fittings, as in the above, it is required to secure the welding length according to the required performance and high quality for welding, so to fill concrete. If it is expected that the concrete will be fixed, it will be necessary to reinforce it with reinforcing bars or steel materials so that the concrete at the fixed part will not be brittlely broken due to repeated loads during an earthquake.

The present invention has been made to solve the above-mentioned problems, and the shearing force and the tensile force acting on the female joint fitting of the ring joint fixed to the main girder are the welding strength with the main girder and the welding strength thereof. The challenge is to propose a fixed structure for joint fittings that is not expected to be of good quality or fixed to the concrete that is filled in the segment steel shell, and that the specifications of the ring joint member are not affected by the thickness of the main girder. And.

In order to solve the above-mentioned problems, the fixing structure of the joint fitting of the present invention is fixed to the main girder of one segment, and the tip of the press-fitting pin portion of the male joint fitting including the fixing portion and the press -fitting pin portion. It is a fixing structure of a joint fitting that fits each other by inserting the side into the recess of the female joint fitting fixed to the main girder of the other segment and joins the main girders of both segments. A part of the female joint fitting is inserted into a through hole provided in the main girder from the back side of the main girder, and the female joint fitting is locked to the back side of the main girder of the other segment. The fixed portion and the press-fitted pin portion are joined by screwing the fixed portion to a screwed portion provided on the base end side of the press-fitted pin portion, and the fixed portion is rotated. This makes it possible to adjust the protrusion length of the press-fitting pin portion inserted into the recess of the female joint fitting from the back surface side of the main girder of the one segment, and after adjusting the protrusion length, the fixing portion. Is characterized by fillet welding to the back surface side of the main girder of the one segment .

Further, in the fixing structure of the joint fitting of the present invention, the outer diameter of the female joint fitting within the insertion range from the joint side end portion of the female joint fitting to the thickness of the main girder or less is about the diameter of the through hole. It is desirable that the outer diameter of the female joint fitting excluding the insertion range is larger than the diameter of the through hole.

Further, the segment is a segment that forms the outer shell of the tunnel by combining a plurality of the segments, and is formed on both sides of the skin plate that forms the outer peripheral surface of the tunnel and the skin plates that are spaced apart from each other in the axial direction of the tunnel. Between the main girders to be erected, the joint plates erected on both end edges of the skin plate at intervals in the circumferential direction of the tunnel, and the main girders on the surface of the skin plate in parallel with the joint plates. Fill the space surrounded by at least the skin plate, the main girder, and the joint plate, and the ribs extending in the above, the segment joint provided in the joint plate for connecting the segments in the circumferential direction, and at least the skin plate, the main girder, and the joint plate. It may be provided with a concrete portion that forms the inner peripheral surface of the tunnel.

According to the fixing structure of the joint fitting of the present invention, the shearing force and the tensile force acting on the female joint fitting of the ring joint fixed to the main girder of the segment are the welding strength with the main girder and its quality, and the segment steel. It is not expected to be fixed to the concrete filled in the shell, and the specifications of the ring joint member are not affected by the thickness of the main girder.

It is explanatory drawing which partially broke in order to explain the structure of the segment to which the fixing structure of the joint fitting of embodiment of this invention is applied.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1-3 is a perspective view illustrating the configuration of segment 1 to which the present embodiment is applied. This segment 1 is an arc plate-shaped member, and a cylindrical lining (outer shell) of a tunnel is formed by combining a plurality of segments 1, ....

Hereinafter, the direction in which the tunnel is extended is referred to as the axial direction of the tunnel, the arc direction of the cylindrical tunnel is referred to as the circumferential direction of the tunnel, the ground side of the lining is referred to as the outer peripheral surface of the tunnel, and the inner air side of the lining. Is called the inner peripheral surface of the tunnel, and the joint surface between the opposing segments 1 and 1 is called the joint surface.

This segment 1 includes a skin plate 2 forming a part of the outer peripheral surface of the tunnel, main girders 3 and 3 erected on both side edges of the skin plate 2, and joints erected on both end edges of the skin plate 2. A composite mainly provided with joint plates 4 and 4 as face portions, ribs 5 and 5A extending between main girders 3 and 3 on the surface of the skin plate 2, and a concrete portion 6 filled in the inner space. It is a segment.

The skin plate 2 is formed by bending a thin rectangular steel plate into a side view arc shape. In this skin plate 2, the long side is the circumferential direction of the tunnel, and the short side is the axial direction of the tunnel.
Further, an arc-shaped main girder 3 is erected along the side edge on the long side of the skin plate 2.
That is, the main girders 3 and 3 are erected in parallel at intervals in the axial direction of the tunnel.
As shown in FIG. 4, the main girder 3 is formed by a pair of flanges 3a and 3a arranged in parallel on the outer peripheral surface side and the inner peripheral surface side of the tunnel and a web 3b connecting the flanges 3a and 3a. , It is molded into a substantially U-shape in cross section.
The flanges 3a and 3a and the web 3b are formed of, for example, a strip-shaped steel plate, and these are substantially orthogonal to each other and are joined by welding or the like. Further, the web 3b is joined so as to project slightly toward the inner peripheral surface side of the flange 3a on the inner peripheral surface side of the tunnel.

Further, as shown in FIG. 1-3, the joint plate 4 stands along the edge on the short side of the skin plate 2 so as to connect the ends of the main girders 3 and 3 in the circumferential direction of the tunnel. Will be set up. The joint plate 4 is formed of, for example, a rectangular steel plate, and is joined to the ends of the main girders 3 and 3 by welding or the like.

As shown in FIG. 1, the joint plate 4 is provided with a segment joint portion 7. The segment joint portion 7 is composed of an insertion fitting 71 and a receiving fitting 72. That is, the receiving metal fitting 72 is attached to the joint plate 4 of another segment 1 connected to the segment 1 in the circumferential direction at a position facing the insertion metal fitting 71, and at a position facing the receiving metal fitting 72. The insertion fitting 71 is attached. Then, by fitting the insertion fitting 71 into the receiving fitting 72, the two segments 1 and 1 are connected in the circumferential direction.

Further, as shown in FIG. 4, the joint plate 4 is provided with an insertion port 72c communicating with the accommodating portion 72b of the receiving metal fitting 72, and the insertion portion 71b of the insertion metal fitting 71 of the segment 1 to be connected to the insertion port 72c. Is inserted and the segment 1 is moved in the axial direction of the tunnel, and the insertion fitting 71 is fitted into the receiving fitting 72.

Further, in the concrete portion 6, a box-shaped space formed by the skin plate 2 and the main girders 3 and 3 and the joint plates 4 and 4 erected on the edge thereof, and the reinforcing reinforcing bars 61, ... Are buried. It is formed by filling concrete to the position where it is to be.

Here, as shown in FIGS. 2 and 3, the concrete portion 6 formed in a layer on the inner peripheral surface side of the tunnel with respect to the main girder 3 is a refractory allowance portion 6a, and the heat generated inside the tunnel is steel. The thickness is set so that it can be prevented from being transmitted to the main girder 3 made of steel.

Further, the concrete portion 6 can be formed of concrete having high fire resistance and mixed with synthetic resin fibers such as polypropylene fiber or vinylon fiber.

Subsequently, with reference to FIG. 5, a detailed configuration of the ring joint portion 8 which is the joint in the tunnel axial direction of the segment 1 will be described.

The ring joint portion 8 is a joint capable of resisting a tensile force in the tunnel axial direction and a shearing force orthogonal to the tensile force in, for example, the tunnel radial direction (inside and outside the tunnel).
As shown in FIG. 5A, the ring joint portion 8 has a male joint fitting 81 provided on one segment 1A side and a female mold provided on the other segment 1B side as shown in FIG. 5B. It is composed of a joint fitting 82.
The male joint fitting 81 includes at least a press-fitting pin portion 811 protruding from the web 3bA of the main girder 3 and a fixing portion 812 embedded inside the segment 1. Further, the female joint fitting 82 includes at least an insert portion 821 that resists a pull-out force when the press-fit pin portion 811 of the male joint fitting 81 is pushed in, and a casing portion 822 that houses the insert portion 821. There is.

The fixing portion 812 and the press-fitting pin portion 811 of the male joint fitting 81 are joined by screwing the fixing portion 812 to the screwing portion 811a provided on the fixing side of the press-fitting pin portion 811. The web 3bA is provided with a through hole 3bA1 having a diameter equal to or larger than the outer diameter of the press-fitting pin portion 811 so that the press-fitting pin portion 811 can be inserted. The protrusion length from the surface web 3bA2 can be adjusted. After adjusting the protrusion length, the corner portion formed by the press-fitting pin portion 811 and the fixing portion 812 and the fixing portion 812 and the web 3bA is fillet welded with the fixing portion 812 in close contact with the web 3bA.
If it is not necessary to adjust the protruding length of the press-fitting pin portion 811, the press-fitting pin portion 811 and the fixing portion 812 may be integrally molded.

A step portion 822a is provided in the insertion range from the joint side end portion of the casing portion 822 of the female joint fitting 82 to the insertion range equal to or less than the thickness of the web 3bB. By making the outer diameter of the step portion 822a similar to the diameter of the through hole 3bB1 provided in the web 3bB, the step portion 822a is inserted into the through hole 3bB1 and the locking portion 822b is locked to the back surface of the web 3bB. In this state, the casing portion 822 and the corner portion formed on the back surface of the web 3bB are fillet welded.

When connecting the ring joint portion 8, first, the male joint fitting 81 of one segment 1A shown in FIG. 5 (a) is connected to the ring joint portion 8 of the other segment 1B shown in FIG. 5 (b). And the segments 1B are moved in the axial direction of the tunnel so that the webs 3bA and 3bB of the segments 1A and 1B are brought into contact with each other.

Then, when the webs 3bA and 3bB come into contact with each other, the press-fitting pin portion 811 protruding from the web 3bA of the male joint fitting 81 is pushed into the insert portion 821 of the facing female joint fitting 82. As a result, the segments 1A and 1B are connected by the ring joint portions 8 and 8.

Next, the operation of the fixing structure of the female joint fitting 82 of the segment 1 of the present embodiment will be described.

According to the fixing structure of the female joint fitting 82 of the present embodiment configured as described above, the stepped portion 822a that can be inserted into the through hole 3bB1 of the main girder 3 on the joint side of the casing portion 822 of the female joint fitting 82. By providing the locking portion 822b, the female joint fitting 82 can be reliably locked to the main girder 3. This makes it possible to deal with the tensile force and the shearing force generated in the female joint fitting 82 without depending on the welding strength and the quality of the female joint fitting 82 and the main girder 3.
That is, in welding, if the strength required for construction such as the frictional force generated by the pressure input and the competition generated when the male joint fitting 81 is press-fitted into the female joint fitting 82 and the strength required for water stoppage are maintained. Well, it is not necessary to determine by external force such as tensile force and shear force.
Further, even when applied to a synthetic segment, it is not necessary to expect fixing to the concrete filled in the steel shell.
Further, since the female joint fitting 82 can be fixed to the main girder 3 with the joint side end of the female joint fitting 82 aligned with the joint surface of the main girder 3, it depends on the thickness of the main girder 3. However, since a constant fitting state can always be ensured, the specifications of the joint member are not affected by the thickness of the main girder 3.
The female joint fittings for ring joints of pin-insertion type fitting joints that are generally on the market are manufactured assuming application to RC segments, and the outer shape excluding the fixing part to concrete is a cylindrical shape with the same diameter. There are many things that do. The stepped portion 822a and the locking portion 822b shown in the present embodiment are simply cut in a range corresponding to the thickness of the main girder from the joint side end portion of such a general-purpose product according to the diameter of the through hole provided in the main girder. It can be formed and does not require special processing even if a general-purpose product is used.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes to the extent that the gist of the present invention is not deviated are made in the present invention. Included in the invention.

For example, in the above-described embodiment, the concrete portion 6 is formed over the entire segment 1, but the present invention is not limited to this, and the skin plate 2, the main girders 3 and 3, and the joint plates 4 and 4 are sufficient. In the segment having high strength, it is not necessary to fill the entire surface of the skin plate 2 with concrete, and the concrete is extended in close proximity to the skin plate 2, the main girders 3 and 3, the joint plate 4 and the joint plate 4. Concrete may be filled only in the space surrounded by the rib 5.

1,1A, 1B Segment 2 Skin plate 3 Main girder 4 Joint plate (joint surface)
5,5A Rib part 51 Notch part 6 Concrete part 62 Spacer 7 Segment joint part 71 Insertion metal fittings 71a Fixing plate part (fixing part)
71c Protrusion 72 Receiving metal fitting 72a Fixing plate (fixing)
72d Protrusion 8 Ring joint 81 Male joint fitting 82 Female joint fitting

Claims (3)

The tip end side of the press-fitting pin portion of the male joint fitting that is fixed to the main girder of one segment and consists of the fixing portion and the press-fitting pin portion is placed in the recess of the female joint fitting fixed to the main girder of the other segment. It is a fixed structure of a joint fitting that fits each other by inserting and joins the main girders of both segments.
A part of the female joint fitting is inserted into a through hole provided in the main girder from the back side of the main girder, and the female joint fitting is locked to the back side of the main girder of the other segment. Welded and fixed to
The fixing portion and the press-fitting pin portion are joined by screwing the fixing portion to a screwing portion provided on the base end side of the press-fitting pin portion.
By rotating the fixing portion, it is possible to adjust the protrusion length of the press-fitting pin portion inserted into the recess of the female joint fitting from the back surface side of the main girder of the one segment.
A fixing structure of a joint fitting, characterized in that the fixing portion is fillet welded to the back surface side of the main girder of the one segment after adjusting the protrusion length . The outer diameter of the female joint fitting in the insertion range equal to or less than the thickness of the main girder from the joint side end of the female joint fitting is about the diameter of the through hole.
The fixing structure for a joint fitting according to claim 1, wherein the outer diameter of the female joint fitting excluding the insertion range is larger than the diameter of the through hole. The segment is a segment that forms the outer shell of a tunnel by combining a plurality of the segments.
The skin plate that forms the outer peripheral surface of the tunnel and
The main girders erected on both sides of the skin plate at intervals in the axial direction of the tunnel,
A joint plate erected on both end edges of the skin plate at intervals in the circumferential direction of the tunnel, and
Ribs extending between the main girders on the surface of the skin plate in parallel with the joint plate,
A segment joint provided on the joint plate for connecting the segments in the circumferential direction, and a segment joint.
The joint according to claim 1 or 2, wherein at least a concrete portion is provided in a space surrounded by the skin plate, the main girder, and the joint plate to form an inner peripheral surface of the tunnel. Fixed structure of hand fittings.

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