JP6652797B2 - Steel pipe joint structure of steel slit dam - Google Patents

Description

  The present invention belongs to a technical field of a joint joint structure between flanged steel pipes constituting a steel slit dam provided between concrete embankments on both banks in a transverse direction of a river.

Steel slit dams are well-established between concrete embankments on both banks in the transverse direction of the river, and are effective in trapping debris and driftwood, and effectively trapping boulders or driftwood. I have.
This steel slit dam is also called a transmission type sabo dam, etc., and until now, various shapes and structures have been disclosed and put into practice (for example, see Patent Documents 1 to 4).
The steel slit dam is constructed by three-dimensionally joining columns and beams made of a steel pipe. In the joining means, a joining portion of each block (part) manufactured in a size suitable for transportation is a steel pipe with a flange, the steel pipes with the flange are butt-joined on site, bolts are passed through the respective flange holes and fastened with nuts. Flange joining is often used (see drawings in Patent Documents 1 to 4 and the like).

JP 2002-188134 A JP 2013-204272 A JP 2009-127280 A JP 2009-24364 A

As described above, flange joining is often used when constructing a steel slit dam. Particularly when performed on the upstream side of a steel slit dam, as shown in FIGS. The impact or the like (see the arrow in the figure) caused by a collision (direct hit) with the joint or the middle part of the steel pipe causes the flange joint to open or misalign (move), resulting in strength and rigidity ( (Suddenly) there is a concern. In addition, there is a concern that other flange joints may be adversely affected, and thus the steel slit dam itself may be collapsed or not used.
Although Patent Document 1 discloses a joining means using a sheath tube (36) as shown in FIG. 12, it is very easy to attach and detach and does not require a skilled worker. There is currently no improved technique for good flange bonding.

  The present invention has been devised in view of the above-described problems of the background art, and its purpose is to increase the shear resistance and bending resistance of the flange joint to open due to the impact of boulders, Alternatively, by preventing the misalignment as much as possible, the strength and rigidity of the flange joint is maintained, and as a result, a steel slit dam with excellent stability and safety that maintains the required strength and rigidity up to a predetermined service life is realized. Another object of the present invention is to provide a steel pipe joint structure of a steel slit dam capable of coping with a recent increase in debris flow scale and unexpected debris flow and boulder collision.

As a means for solving the above problems, a steel pipe joint structure of a steel slit dam according to the invention described in claim 1 is provided with a flange of a steel slit dam provided between concrete embankments on both banks in a transverse direction of a river. In steel pipe joint structure,
At the joining end of one of the flanged steel pipes, a mortise member having a smaller diameter than the steel pipe that can be inserted into the other flanged steel pipe is protruded, and the mortise member is inserted into the other flanged steel pipe. Then, the flanges of the steel pipes to be joined are flange-joined in a state where the flanges abut each other .

  According to a second aspect of the present invention, in the steel pipe joint structure for a steel slit dam according to the first aspect, the one flanged steel pipe is an annular or disk-shaped flanged steel pipe protruding outward from the steel pipe. It is characterized by being.

The steel pipe joint structure of a steel slit dam according to the invention described in claim 3 is a steel pipe joint structure with a flange of a steel slit dam provided between concrete embankments on both banks in a transverse direction of a river,
At the joint end of one flanged steel pipe, a tenon member smaller in diameter than the steel pipe insertable into the other flanged steel pipe is inscribed on the inner surface of the joint end of the one flanged steel pipe. The protruding part of the tenon member is inserted into the other flanged steel pipe, and the flanges of the steel pipes to be joined are flange-joined in a state where the flanges of the steel pipes are joined to each other. It is characterized by becoming.
The steel pipe joint structure of a steel slit dam according to the invention described in claim 4 is a steel pipe joint structure with a flange of a steel slit dam provided between concrete embankments on both banks in a transverse direction of a river,
Joint end portion of one of the flanged steel pipe is greater diameter steel pipe than the other flanged steel pipe is found attached integrally, the joint end portion of the other flanged steel tubes, a portion of the inner than the edge An annular flange is provided externally, and a steel pipe projecting outward from the annular flange is inserted into the enlarged steel pipe of the one flanged steel pipe, and the flanges of the steel pipes to be joined are brought into contact with each other. It is characterized by being flanged.

The steel pipe joint structure of the steel slit dam according to the invention described in claim 5 is a steel pipe joint structure with a flange of a steel slit dam provided between concrete embankments on both banks in a transverse direction of a river,
The one flanged steel pipe and the other flanged steel pipe are characterized in that they are flange-joined by co-tightening via an inner sleeve member having an annular flange externally provided at the center.

According to a sixth aspect of the present invention, in the steel pipe joint structure for a steel slit dam according to the fifth aspect of the present invention, the two steel pipes with flanges have annular flanges protruding inward and outward of the steel pipe. A key groove is formed at the protrusion of the inner sleeve member, and the inner sleeve member has a size that can be inserted into the annular flange of the steel pipe, and a key is externally provided at both ends in the pipe axial direction, and the inner sleeve member is provided inside the key groove. It is characterized in that the inserted key is rotated to make it impossible to pull out and then flanged.

The invention described in claim 7 is the steel pipe joint structure of the steel slit dam according to any one of claims 1 to 6 , wherein the outer peripheral surface of the flange of the one or other flanged steel pipe has: A protection casing for covering the flange joint is provided.

According to the steel pipe joint structure of the steel slit dam according to the present invention, the following effects can be obtained.
(1) In addition to the conventional general flange joint (butt bolt joint), a so-called double pipe structure in which a tenon member or the like is fitted into an annular flange and held (held) as in the relationship between a tenon and a tenon hole can be realized. Further, it is possible to further firmly join, and it can also contribute to prevention of warpage and twisting of the tenon member and the like, and furthermore, the steel pipes joined to each other.
Therefore, since the shear resistance and the bending resistance of the flange joint can be effectively increased, the strength and rigidity of the flange joint can be maintained by minimizing opening or misalignment due to impact of boulders. In addition, a steel slit dam with excellent stability and safety that maintains the required strength and rigidity up to the specified service life has been realized, and is capable of responding to the recent increase in debris flow scale and unexpected scale debris flow and boulder collision. Can respond.
In addition, the above-described operation and effect can be realized by the same procedure and labor as the conventional general flange joining operation, so that it is extremely rational.
(2) According to the steel pipe joint structure of the steel slit dam according to claim 5 , in addition to the above operation and effect (1), when the member corresponding to the inner pipe constituting the double pipe structure is damaged, etc. Can be easily replaced. In addition, since the flange joint can be realized with three flanges, the thickness per sheet can be reduced, and the welding work of the flange can be saved.
(3) According to the steel pipe joint structure of the steel slit dam according to the sixth aspect , in addition to the above effects (1) and (2), the bending resistance is further enhanced by the detachment preventing effect of the key and the key groove. Can be.
(4) According to the steel pipe joint structure of the steel slit dam according to claim 7 , in addition to the effect (1), since the protective casing protects the flange joint portion from the direct impact of the boulders, it opens due to the impact of the boulders, Alternatively, misalignment can be further prevented.

FIG. 1A is an exploded perspective view schematically showing a joining mode of a steel pipe joint structure of a steel slit dam according to a first embodiment, FIG. 1B is a front view showing a flange joining section, and FIG. It is CC sectional view taken on the line. A is a front view showing a flange joint portion of the steel pipe joint structure of the steel slit dam according to Example 2, and B is a cross-sectional view of A taken along line BB. A is a front view showing a flange joint portion of the steel pipe joint structure of the steel slit dam according to Example 3, and B is a cross-sectional view of A taken along line BB. A is an exploded perspective view schematically showing a joining mode of a steel pipe joint structure of a steel slit dam according to Example 4, B is a front view showing a flange joining section, and C is a B view of FIG. It is CC sectional view taken on the line. A is an exploded perspective view schematically showing a joining mode of a steel pipe joint structure of a steel slit dam according to Example 5, B is a front view showing a flange joint, and C is a sectional view of FIG. It is CC sectional view taken on the line. A is an exploded perspective view schematically showing a joining mode of a steel pipe joint structure of a steel slit dam according to Example 6, B is a front view showing a flange joint, and C is a sectional view of B. It is CC sectional view taken on the line. A is a front view showing a flange joint portion of the steel pipe joint structure of the steel slit dam according to Example 7, and B is a cross-sectional view of A taken along line BB. A is an exploded perspective view schematically showing a joining mode of a steel pipe joint structure of a steel slit dam according to Example 8, B is a front view showing a flange joint, and C is a flange side. It is a side view of the steel pipe with a flange seen from, and D is a side view of the inner sleeve member. A is a front view schematically showing a steel pipe joint structure of a steel slit dam according to the related art, and B is a front view schematically showing a state in which a flange joint is opened due to boulder impact or the like. FIG. 4C is a front view schematically showing a state in which the flange joint is misaligned due to bombardment impact or the like. Is a front view schematically showing a steel pipe joint structure of a steel slit dam according to the prior art, and B is a front view schematically showing a state in which a flange joint is opened due to boulder impact or the like. C is a front view schematically showing a state in which the flange joint is misaligned due to bombardment impact or the like.

The present invention relates to a flanged steel pipe joint structure of a steel slit dam provided between concrete levee bodies on both banks in the transverse direction of a river, and more specifically to reinforcing (strengthening) the flange joint, specifically, in the following examples. In brief, the flange joint is formed into a so-called double-pipe structure by fitting a tenon part or the like, and is based on a technical idea of increasing a shear resistance and a bending resistance.
In addition, the drawings used for describing the embodiments show a case where they are horizontally joined as an example for convenience of illustration, but are not limited to this. The portion to which the present invention (the steel pipe joint structure with flange according to the present invention) is applied has no directionality, and is appropriately added and joined in all directions such as a horizontal direction, a vertical direction, and an inclined direction to form a steel slit dam three-dimensionally. be able to. Of course, the present invention may be applied to all the joints, or may be applied only to important points (for example, only a steel pipe installed on the upstream side). There are various implementation variations.
Hereinafter, an embodiment of a steel pipe joint structure with a flange of a steel slit dam according to the present invention will be described with reference to the drawings.

As shown in FIGS. 1A to 1C, the steel pipe joint structure of the steel slit dam according to the first embodiment has a flange of a steel slit dam (not shown) provided between concrete embankments on both banks in the transverse direction of the river. It has a steel pipe joint structure, and at the joining end of one flanged steel pipe 1, a tenon member 5 having a smaller diameter than the steel pipe insertable into the other flanged steel pipe 2 is provided to protrude. 5 is inserted into the other flanged steel pipe 2, and the flanges of the steel pipes to be joined are flanged and joined together.
Incidentally, reference numeral 3 in the drawing indicates a disk-shaped flange protruding outward from the steel pipe, and reference numeral 4 indicates an annular flange protruding outward from the steel pipe.

As a precautionary measure, the flange joining means that the flanged steel pipes 1 and 2 (strictly speaking, the flanges 3 and 4) are abutted to each other, the bolts 6 are passed through the flange holes 3a and 4a whose cores are aligned, and the nuts 7 are fastened. Means to join.
The size (form) of the steel pipes 1 and 2 used in the present embodiment is appropriately changed depending on the structural design, but generally the outer diameter (φ) is about 400 to 600 mm and the thickness (t) is about 9 to 22 mm. It is a target. Of course, it is preferable that the sizes of the steel pipes 1 and 2 to be flange-joined are matched.
The same technical idea is applied to the embodiments described below.

More specifically, the one flanged steel pipe 1 has an outer diameter of about 400 mm and a plate thickness of about 9 mm. A disc-shaped flange 3 having an outer diameter of about 600 mm and a plate thickness of about 36 mm is fixed (fixed) to the joining edge of the steel pipe 1 by welding (all-around welding) so that the steel pipe 1 and the core are aligned. . Furthermore, a cylindrical tenon member 5 having an outer diameter of about 250 mm, a plate thickness of about 7 mm, and a total length of about 250 mm is provided on the outer surface of the disc-shaped flange 3 so that the core coincides with the steel pipe 1 and the disc-shaped flange 3. Is fixed by welding.
The other flanged steel pipe 2 has an outer diameter of about 400 mm and a thickness of about 9 mm. An annular flange 4 having an outer diameter of about 600 mm, an inner diameter of about 250 mm, and a plate thickness of about 36 mm is fixed to the joining edge of the steel pipe 2 by welding so that the steel pipe 2 and the core are aligned. That is, the inner diameter of the annular flange 4 is set to a size such that the tenon member 5 is substantially inscribed.
Accordingly, when the mortise member 5 (about 250 mm in outer diameter) of the one flanged steel pipe 1 is fitted into the annular flange 4 (about 250 mm in inner diameter) of the other flanged steel pipe 2 and further advanced, the steel pipe 1, The two flanges 3 and 4 are configured to abut each other. Thereafter, so-called flange joining is performed in which the bolts 6 are passed through the flange holes 3a and 4a having the aligned cores and fastened by the nuts 7 to join, thereby realizing a steel pipe joint structure.
In addition, each said dimension is only an example, and can be changed suitably according to a structural design.

According to the steel pipe joint structure of the steel slit dam having the above-described structure, in addition to the conventional general flange connection (butting bolt connection), the mortise member 5 is fitted into the annular flange 4 as shown in the relationship between the mortise and the mortise hole, and restrained. Since a so-called double pipe structure held (held) can be realized, it is possible to further firmly join and contribute to prevention of warpage and twisting of the tenon member 5 and thus the steel pipes 1 and 2.
Therefore, since the shear resistance and the bending resistance of the flange joint can be effectively increased, the strength and rigidity of the flange joint can be maintained by minimizing opening or misalignment due to impact of boulders. In addition, a steel slit dam with excellent stability and safety that maintains the required strength and rigidity up to the specified service life has been realized, and is capable of responding to the recent increase in debris flow scale and unexpected scale debris flow and boulder collision. Can respond.
In addition, the above-described operation and effect can be realized by the same procedure and labor as those of the conventional general flange joining operation, which is extremely reasonable.

  The steel pipe joint structure of the steel slit dam shown in FIGS. 2A and 2B is different from the first embodiment only in the form of the tenon member 5 and the form of the annular flange 4 associated therewith. The other components are the same as those in the first embodiment, and thus are denoted by the same reference numerals and description thereof will be omitted as appropriate.

That is, the steel pipe joint structure of the steel slit dam according to the second embodiment has a cylindrical shape having an outer diameter of about 382 mm, a plate thickness of about 7 mm, and a total length of about 250 mm on the outer surface of the disk-shaped flange 3 of the one flanged steel pipe 1. A tenon member 5 ′ having a shape is fixed by welding so that the steel tube 1 and the disk-shaped flange 3 are aligned with the core.
An annular flange 4 'having an outer diameter of about 600 mm, an inner diameter of about 382 mm, and a thickness of about 36 mm is fixed to the joining edge of the other flanged steel pipe 2 by welding so that the steel pipe 2 and the core are aligned. . That is, the inner diameters of the annular flange 4 ′ and the steel pipe 2 are set to a size such that the tenon member 5 ′ is substantially inscribed.
Therefore, when the tenon member 5 '(outer diameter of about 382 mm) of the one flanged steel pipe 1 is fitted into the annular flange 4' (about 382 mm in inner diameter) of the other flanged steel pipe 2 and further advanced, the steel pipe is inserted. The first and second flanges 3 and 4 'are configured to abut each other. Thereafter, so-called flange joining is performed in which the bolts 6 are passed through the flange holes having the aligned cores and the nuts 7 are fastened and joined, thereby realizing a steel pipe joint structure.
In addition, each said dimension is only an example, and can be changed suitably according to a structural design.

According to the steel pipe joint structure of the steel slit dam having the above configuration, the same operation and effect as those of the first embodiment can be obtained.
That is, in addition to the conventional general flange joining, a so-called double pipe structure in which the tenon member 5 ′ is fitted into the annular flange 4 ′ (steel pipe 2) and restrained (held) as in the relationship between a tenon and a mortise hole is realized. Therefore, it is possible to further firmly join, and it is possible to contribute to prevention of warpage and twist of the tenon member 5 ′ and thus the steel pipes 1 and 2.
Therefore, since the shear resistance and the bending resistance of the flange joint can be effectively increased, the strength and rigidity of the flange joint can be maintained by minimizing opening or misalignment due to impact of boulders. In addition, a steel slit dam with excellent stability and safety that maintains the required strength and rigidity up to the specified service life has been realized, and is capable of responding to the recent increase in debris flow scale and unexpected scale debris flow and boulder collision. Can respond.
In addition, the above-described operation and effect can be realized by the same procedure and labor as the conventional general flange joining operation, so that it is extremely rational.

  In the steel pipe joint structure of the steel slit dam shown in FIGS. 3A and 3B, both the flanges 3 and 4 have the same shape as the annular flange 4 ′ of the second embodiment, as compared with the first embodiment. Only the form of the tenon member 5 is different. The other components are the same as those in the first embodiment, and thus are denoted by the same reference numerals and description thereof will be omitted as appropriate.

That is, in the steel pipe joint structure of the steel slit dam according to the third embodiment, an annular flange 3 having an outer diameter of about 600 mm, an inner diameter of about 382 mm, and a plate thickness of about 36 mm is provided at the joining edge of the one flanged steel pipe 1. Is fixed by welding so that the steel tube 1 and the core are aligned. Further, a part (150 mm) of a cylindrical tenon member 5v having an outer diameter of about 382 mm, a plate thickness of about 7 mm, and a total length of about 400 mm is inscribed on the inner surface of the steel pipe 1 with the flange 3 ′ to partially ( (About 250 mm) so as to project outward.
The form of the other flanged steel pipe 2 is the same as that of the second embodiment, and an annular flange 4 ′ having an outer diameter of about 600 mm, an inner diameter of about 382 mm, and a plate thickness of about 36 mm is formed at the joining edge thereof. It is fixed by welding so that the cores coincide. That is, the inner diameter of the annular flange 4 ′ and the inner diameter of the steel pipe 2 are set to a size such that the tenon member 5 v is substantially inscribed.
Accordingly, when the tenon member 5v (about 382 mm in outer diameter) of the one flanged steel pipe 1 is fitted into the annular flange 4 ′ (about 382 mm in inner diameter) of the other flanged steel pipe 2 and further advanced, the steel pipe 1 is inserted. The two flanges 3 ′ and 4 ′ abut each other. Thereafter, so-called flange joining is performed in which the bolts 6 are passed through the flange holes having the aligned cores and the nuts 7 are fastened and joined, thereby realizing a steel pipe joint structure.
In addition, each said dimension is only an example, and can be changed suitably according to a structural design.

According to the steel pipe joint structure of the steel slit dam having the above configuration, the same operation and effect as those of the first and second embodiments can be obtained.
That is, in addition to the conventional general flange joining, a so-called double pipe structure in which the tenon member 5v is fitted and restrained (held) in the annular flange 4 '(steel pipe 2) as in the relationship between a tenon and a tenon hole can be realized. Therefore, it is possible to join more firmly, and it is also possible to contribute to prevention of warpage and twisting of the mortise member 5v and thus the steel pipes 1 and 2.
Therefore, since the shear resistance and the bending resistance of the flange joint can be effectively increased, the strength and rigidity of the flange joint can be maintained by minimizing opening or misalignment due to impact of boulders. In addition, a steel slit dam with excellent stability and safety that maintains the required strength and rigidity up to the specified service life has been realized, and is capable of responding to the recent increase in debris flow scale and unexpected scale debris flow and boulder collision. Can respond.
In addition, the above-described operation and effect can be realized by the same procedure and labor as the conventional general flange joining operation, so that it is extremely rational.

The steel pipe joint structure of the steel slit dam according to the fourth embodiment is, as shown in FIGS. 4A to 4C, a flanged steel pipe joint structure of a steel slit dam provided between concrete embankments on both banks in the transverse direction of the river. The joint end of one flanged steel pipe 11 is integrally attached with an enlarged steel pipe 11a larger than the other flanged steel pipe 12, and the joint end of the other flanged steel pipe 12 is closer to the end. An annular flange 14 is externally provided at an inner portion (in this embodiment, a portion where the steel pipe 12 protrudes by a length L (see FIG. 4B) in the pipe axis direction of the enlarged diameter steel pipe 11a). The steel pipe 12 protruding outward from 14 is inserted into the enlarged diameter steel pipe 11a of the one flanged steel pipe 11, and the flanges of the steel pipes to be joined are flange-joined in a state where the flanges abut each other. .
Reference numeral 13 in the drawing indicates an annular flange.

Specifically, the one flanged steel pipe 11 has an outer diameter of about 400 mm and a plate thickness of about 9 mm, and the expanded steel pipe 11a has an outer diameter of about 418 mm, a plate thickness of about 9 mm, and a pipe axial length. Is implemented in a form of about 220 mm. Further, an outer diameter of about 600mm on the outer peripheral surface of the edge of the enlarged diameter steel pipe 11a, an inner diameter of about 418Mm, as annular flange 13 about the plate thickness 36mm is the steel pipe 11 and the enlarged diameter steel pipe 11a and the core are matched welding Is fixed.
The other flanged steel pipe 12 has an outer diameter of about 400 mm and a plate thickness of about 9 mm, and the flange 14 provided on the steel pipe 12 has an outer diameter of about 600 mm, an inner diameter of about 400 mm, and a plate thickness of about 36 mm. The steel pipe 12 and the core are fixed by welding so as to coincide with the core. That is, the inner diameter (400 mm) of the enlarged diameter steel pipe 11a is set to a size such that the steel pipe 12 is substantially inscribed.

As described above, the annular flange 13 provided on the one flanged steel pipe 11 side and the annular flange 14 provided on the other flanged steel pipe 12 have the same outer diameter and different inner diameters. Of course, the flange holes 13a and 14a are provided so that the cores coincide. As described above, in the present embodiment, the flange 14 is provided at a position where the steel pipe 12 protrudes by the length in the pipe axis direction (L = about 220 mm) of the expanded steel pipe 11a, but is not limited thereto. It may be shorter than the above dimensions (for example, L = about 50 mm). However, the longer the L dimension, the greater the shear resistance and bending resistance.

In addition, each said dimension is only an example, and can be changed suitably according to a structural design. In particular, the projecting dimension L of the steel pipe 12 is set to a dimension that can effectively exert the shear resistance and the bending resistance. For example, the outer diameter of the steel pipes 11 and 12 to be used, such as 50 to 300 mm, is (φ). Then, it is preferable to carry out the process in the range of 1 / 2φ to 1φ.
Thus, when the other flanged steel pipe 12 is fitted into the expanded steel pipe 11a of the one flanged steel pipe 11 and further advanced, the flanges 13 and 14 of the steel pipes 11 and 12 abut against each other. After that, a so-called flange joint in which the bolts 6 are passed through the flange holes 13a and 14a having the aligned cores and fastened with the nuts 7 to perform joining is realized, thereby realizing a steel pipe joint structure.

According to the steel pipe joint structure of the steel slit dam having the above-described configuration, in addition to the conventional general flange connection (butt bolt connection), the steel pipe 12 is fitted into the enlarged diameter steel pipe 11a as in the relationship between a mortise and a mortise hole and restrained ( Since a so-called double-pipe structure which is held) can be realized, it is possible to join more firmly and to contribute to prevention of warpage and twist of the steel pipes 11 and 12.
Therefore, since the shear resistance and the bending resistance of the flange joint can be effectively increased, the strength and rigidity of the flange joint can be maintained by minimizing opening or misalignment due to impact of boulders. In addition, a steel slit dam with excellent stability and safety that maintains the required strength and rigidity up to the specified service life has been realized, and is capable of responding to the recent increase in debris flow scale and unexpected scale debris flow and boulder collision. Can respond.
In addition, the above-described operation and effect can be realized by the same procedure and labor as the conventional general flange joining operation, so that it is extremely rational.
[Example 5]

The steel pipe joint structure of the steel slit dam shown in FIGS. 5A to 5C is different from that of the fourth embodiment in that the protective casing 15 covering the flange joint is provided on the outer peripheral surface of the flange 13 of the one flanged steel pipe 11. The difference is that they are provided. The other components are the same as those in the fourth embodiment, and thus are denoted by the same reference numerals and description thereof will be omitted as appropriate.

That is, in the steel pipe joint structure of the steel slit dam according to the fifth embodiment, as shown in FIGS. 5A to 5C, the protective casing 15 is formed in an annular shape having an L-shaped cross section. The cylindrical portion circumscribing the outer peripheral surface of the flange 13 of the flanged steel pipe 11 has an outer diameter of about 620 mm, an inner diameter of about 600 mm, and a plate thickness of about 12 mm. It is formed in an annular shape with an outer diameter of about 624 mm and an inner diameter of about 400 mm.
Further, the length of the protective casing 15 in the tube axis direction is such that the distal end edge of the cylindrical portion covers the flange joint when the bottom portion is hung on the base end (step portion) of the expanded steel pipe 11a (specifically, Specifically, from the left side to the right side in FIG. 5B, the thickness of the bottom portion (5 mm), the total length of the expanded steel pipe 11a (220 mm), the thickness of the flange 14 (36 mm), and the head of the bolt 6 (20 mm) are added. 281 mm).

The form of the protective casing 15 is of course not limited to the above dimensions, and it is sufficient that the protective casing 15 is fixed to the flanged steel pipe 11 with required strength and rigidity so as to cover the flange joint. Although not shown, the protective casing 15 may be fixed to the other flanged steel pipe 12 with the required strength and rigidity so that the flange joint can be covered again. it can.
However, the nut 7 is welded to the flange 13 (flange hole 13a) on the side where the protective casing 15 is provided in advance in consideration of the bolt joining operation.

Thus, when the other flanged steel pipe 12 is fitted into the expanded steel pipe 11a of the one flanged steel pipe 11 and further advanced, the flanges 13 and 14 of the steel pipes 11 and 12 abut against each other. Thereafter, in each of the flange holes 13a and 14a whose cores are aligned, a so-called flange joint is performed in which the bolt 6 is joined to the welding nut 7 provided on the flange hole 13a side to realize a steel pipe joint structure.

  According to the steel pipe joint structure of the steel slit dam having the above configuration, in addition to the same operation and effect as in the fourth embodiment (see paragraph [0029]), since the protective casing 15 protects the flange joint from direct impact of boulders. By maintaining the strength and rigidity of the flange joint by further preventing opening or misalignment due to boulder impact, etc., the stability and safety of the required strength and rigidity up to the specified service life are maintained. It realizes an excellent steel slit dam and can cope with the recent increase in debris flow scale and unexpected scale of debris flow and boulder collision.

The steel pipe joint structure of the steel slit dam according to the sixth embodiment is, as shown in FIGS. 6A to 6C, a flanged steel pipe joint structure of a steel slit dam provided between concrete embankments on both banks in the transverse direction of the river. In addition, one flanged steel pipe 21 and the other flanged steel pipe 22 are flange-joined by co-tightening via an inner sleeve member 23 having an annular flange 26 provided at the center (intermediate part).
Incidentally, reference numerals 24 and 25 in the drawing indicate a pair of annular flanges.

More specifically, the one flanged steel pipe 21 has an outer diameter of about 400 mm and a thickness of about 9 mm. An annular flange 24 having an outer diameter of about 600 mm, an inner diameter of about 382 mm, and a plate thickness of about 24 mm is fixed to the joining edge of the steel pipe 21 by welding so that the steel pipe 21 and the core are aligned.
The other flanged steel pipe 22 has the same shape and the same size as the one flanged steel pipe 21 (the pipe shaft length is not considered).
The inner sleeve member 23 has a cylindrical shape with an outer diameter of about 382 mm, a plate thickness of about 9 mm, and a length in the tube axis direction of about 470 mm. The annular flange 26 provided outside the member 23 has an outer diameter of about 600 mm, an inner diameter of about 382 mm, and a plate thickness of about 24 mm.

That is, the inner diameter (382 mm) of each of the flanged steel pipes 21 and 22 is set to a size such that the inner sleeve member 23 is substantially inscribed. Of course, the flange holes 24a, 25a, and 26a provided in the annular flanges 24, 25, and 26 are provided so that the cores are aligned.
In addition, each said dimension is only an example, and can be changed suitably according to a structural design. In particular, the length of the inner sleeve member 23 in the tube axis direction is set to a size capable of effectively exhibiting the shear resistance and the bending resistance at the flange joint portion, and is, for example, 100 to 600 mm or the like. When the outer diameter of the steel pipe is (φ), it is preferable to perform the processing in a range of 1φ to 2φ (that is, a range in which the steel pipes 21 and 22 are evenly spread by 1 / 2φ to 1φ each).

  Thus, when the inner sleeve member 23 is fitted into the one flanged steel pipe 21 and the other flanged steel pipe 22, the annular flanges 24, 25, 26 abut each other, The inner sleeve member 23 has a structure that straddles both the steel pipes 21 and 22 evenly. After that, a so-called flange joint is performed in which the bolts 6 are passed through the flange holes 24a, 25a, and 26a whose cores are aligned and fastened by the nuts 7 to join, thereby realizing a steel pipe joint structure.

According to the steel pipe joint structure of the steel slit dam having the above-described configuration, in addition to the conventional general flange joining, the inner sleeve member 23 substantially evenly straddles the steel pipes 21 and 22 as in the relationship between a tenon and a tenon hole. A so-called double pipe structure fitted and held (held) as described above can be realized, so that it is possible to join more firmly and to contribute to prevention of warpage and twist of the inner sleeve member 23, and furthermore, the steel pipes 21 and 22. .
Therefore, since the shear resistance and the bending resistance of the flange joint can be effectively increased, the strength and rigidity of the flange joint can be maintained by minimizing opening or misalignment due to impact of boulders. In addition, a steel slit dam with excellent stability and safety that maintains the required strength and rigidity up to the specified service life has been realized, and is capable of responding to the recent increase in debris flow scale and unexpected scale debris flow and boulder collision. Can respond.

In addition, when a member corresponding to the inner tube constituting the double tube structure (the inner sleeve member 23 in the sixth embodiment) is damaged or the like, the replacement operation of the inner tube is easier than in the first to fifth embodiments. Can be done.
In addition, when constructing the flange joint, in the above Examples 1 to 5, two flanges achieve a total flange thickness of 72 mm, but in Example 6, three flanges achieve the same flange thickness. Therefore, the thickness per sheet can be reduced. Therefore, labor for welding the flange can be saved.

  The steel pipe joint structure of the steel slit dam shown in FIGS. 7A and 7B differs from that of the sixth embodiment only in the outer diameter of the inner sleeve member 23 and the form of the annular flanges 24, 25 and 26 associated therewith. . The other components are the same as those in the sixth embodiment, and thus are denoted by the same reference numerals and description thereof will be omitted as appropriate.

That is, in the steel pipe joint structure of the steel slit dam according to the seventh embodiment, the inner sleeve member 23 'is formed in a cylindrical shape having an outer diameter of about 250 mm, a plate thickness of about 7 mm, and a length in the pipe axis direction of about 470 mm. ing. The annular flange 26 'provided outside the member 23' has an outer diameter of about 600 mm, an inner diameter of about 250 mm, and a plate thickness of about 24 mm.
Accordingly, an annular flange 24 ′ having an outer diameter of about 600 mm, an inner diameter of about 250 mm, and a plate thickness of about 24 mm is fixed to the joining edge of one of the flanged steel pipes 21 by welding so that the core is aligned with the steel pipe 21. Have been.
Similarly to the one flanged steel pipe 21, the other flanged steel pipe 22 has an annular flange 25 ′ having an outer diameter of about 600 mm, an inner diameter of about 250 mm, and a plate thickness of about 24 mm at the joining edge thereof. Are fixed by welding so as to coincide with each other.
That is, the inner diameters (250 mm) of the annular flanges 24 ′, 25 ′ of the flanged steel pipes 21, 22 are both sized such that the inner sleeve member 23 ′ is substantially inscribed.

  Thus, when the inner sleeve member 23 ′ is fitted into the annular flange 24 ′ of the one flanged steel pipe 21 and the other inner flange member 23 ′ is fitted into the annular flange 25 ′ of the other flanged steel pipe 22, the respective annular flanges 24 ′ are formed. , 25 ', 26' abut each other, and the inner sleeve member 23 'straddles both the steel pipes 21, 22 evenly. Thereafter, the steel pipe joint structure is realized by performing so-called flange joining in which the bolts 6 are passed through the flange holes having the aligned cores and fastened with the nuts 7 to join.

According to the steel pipe joint structure of the steel slit dam having the above configuration, the same operation and effect as those of the sixth embodiment can be obtained.
That is, in addition to the conventional general flange joining, the inner sleeve member 23 'is fitted into the steel pipes 21 and 22 so as to straddle substantially evenly as in the relationship between a tenon and a tenon hole, and both annular flanges 24', Since a so-called double pipe structure restrained (held) by 25 'can be realized, it is possible to join more firmly and to contribute to prevention of warping and twisting of the inner sleeve member 23' and thus the steel pipes 21 and 22. .
Therefore, since the shear resistance and the bending resistance of the flange joint can be effectively increased, the strength and rigidity of the flange joint can be maintained by minimizing opening or misalignment due to impact of boulders. In addition, a steel slit dam with excellent stability and safety that maintains the required strength and rigidity up to the specified service life has been realized, and is capable of responding to the recent increase in debris flow scale and unexpected scale debris flow and boulder collision. Can respond.
In addition, as compared with the above-described first to fifth embodiments, the replacement operation can be easily performed, and the welding operation of the flange can be saved.

  The steel pipe joint structure of the steel slit dam shown in FIGS. 8A to 8D differs from that of the sixth embodiment in that the inner sleeve member 23 and the pair of flanged steel pipes 21 and 22 (not taken into account for the length of the steel pipe). The same points are used for joining. However, by forming a key groove on the steel pipes 21 and 22 side and forming a key on the inner sleeve member 23, the joining force (particularly, bending resistance) between the joined steel pipes 21 and 22 is increased. Different.

  That is, in the steel pipe joint structure of the steel slit dam according to the eighth embodiment, both the flanged steel pipes 31 and 32 include the annular flanges 34 and 35 protruding inward and outward of the steel pipes 31 and 32, respectively. The inner sleeve member 33 is sized to be inserted into the annular flanges 34, 35 of the steel pipes 31, 32, and the keys 33b, 33b are provided at both ends in the pipe axis direction. The keys 33b, 33b inserted in the key grooves 34b, 35b are externally provided, and the keys 33b, 33b are rotated so that they cannot be pulled out, and are flanged.

Specifically, the one flanged steel pipe 31 has an outer diameter of about 400 mm and a plate thickness of about 9 mm. An annular flange 34 having an outer diameter of about 600 mm, an inner diameter of about 310 mm, and a plate thickness of about 24 mm is fixed to the joining edge of the steel pipe 31 by welding so that the steel pipe 31 and the core are aligned. Further, the inner peripheral surface of the annular flange 34 is partially cut out in an arc shape to form a key groove 34b.
Similarly, the configuration of the other flanged steel pipe 32 is implemented with an outer diameter of about 400 mm and a plate thickness of about 9 mm, and the joining edge of the steel pipe 32 has an outer diameter of about 600 mm, an inner diameter of about 310 mm, and a thickness of about 310 mm. An annular flange 35 of about 24 mm is fixed by welding so that the steel pipe 32 and the core are aligned. Further, the inner peripheral surface of the annular flange 35 is partially cut out in an arc shape to form a key groove 35b.
On the other hand, the inner sleeve member 33 has a cylindrical shape with an outer diameter of about 310 mm, a plate thickness of about 7 mm, and a length in the tube axis direction of about 160 mm. The annular flange 36 provided at the center of the member 33 has an outer diameter of about 600 mm, an inner diameter of about 310 mm, and a plate thickness of about 19 mm. Further, keys 33b, 33b of a size that can be inserted into the key grooves 34b, 35b are externally provided (projected) by welding or integral molding at both ends in the tube axis direction of the inner sleeve member 33. In this embodiment, as an example, the key 33b is formed in an arc shape slightly smaller than the key grooves 34b and 35b, and has a width (length in the tube axis direction) of about 25 mm.

Thus, the inner sleeve member 33 is inserted into the annular flange 34 of the one flanged steel pipe 31 by aligning the corresponding key 33b with the key groove 34b, and then the other flanged steel pipe 32 (the annular The flange 35) is fitted into the inner sleeve member 33 by aligning the corresponding key 33b with the key groove 35b, and butting the flanges (34, 35, 36) of the three members. Thereafter, the inner sleeve member 33 is rotated by a required angle (about one or two flange holes).
Then, the inner sleeve member 33 straddles both of the steel pipes 31 and 32 evenly in a state where the inner sleeve member 33 cannot be pulled out due to the key effect. Thereafter, the steel pipe joint structure is realized by performing so-called flange joining in which the bolts 6 are passed through the flange holes having the aligned cores and fastened with the nuts 7 to join.
In addition, the key 33b and the key groove 34b can be provided at a plurality of locations with good balance. Further, the number of the key grooves 34b may be formed to be larger than the number of the keys 33b so that the alignment operation can be performed efficiently.

  According to the steel pipe joint structure of the steel slit dam having the above-described configuration, in addition to the same operation and effect as in the seventh embodiment (see paragraph [0044]), the key 33b and the key grooves 34b and 34b are bent by the detachment preventing effect. Resistance can be further increased.

Although the embodiments have been described with reference to the drawings, the present invention is not limited to the illustrated examples, and includes a range of design changes and application variations that are normally performed by those skilled in the art without departing from the technical idea thereof. I will mention it just in case.
For example, the protective casing 15 (see FIG. 5) described in the fifth embodiment is not limited to being applied to the fourth embodiment (see FIG. 4), but may be applied to other embodiments, that is, the first to third embodiments (see FIG. 5). 1 to 3) and Embodiments 6 to 8 (see FIGS. 6 to 8), and similar effects can be obtained.

Reference Signs List 1 steel pipe with flange 2 steel pipe with flange 3 disk-shaped flange 3a flange hole 3 'annular flange 4 annular flange 4a flange hole 4' annular flange 5 mortise member 5 'mortise member 5v mortise member 6 bolt 7 nut 11 with flange Steel pipe 11a Expanded steel pipe 12 Flanged steel pipe 13 Annular flange 13a Flange hole 14 Annular flange 14a Flange hole 15 Protective casing 21 Flanged steel pipe 22 Flanged steel pipe 23 Inner sleeve member 23 'Inner sleeve member 24 Annular flange 24a Flange hole 24 'Annular flange 25 Annular flange 25a Flange hole 25' Annular flange 26 Annular flange 26a Flange hole 26 'Annular flange 31 Flanged steel pipe 32 Flanged steel pipe 33 Inner sleeve member 33 b key (projecting part)
34 annular flange 34b key groove 35 annular flange 35b key groove 36 annular flange

Claims (7)

In a steel pipe joint structure with a flange of a steel slit dam installed between concrete embankments on both banks in the transverse direction of the river,
At the joining end of one of the flanged steel pipes, a mortise member having a smaller diameter than the steel pipe that can be inserted into the other flanged steel pipe is protruded, and the mortise member is inserted into the other flanged steel pipe. A steel pipe joint structure for a steel slit dam , wherein the flanges of the steel pipes to be joined are flanged in a state where the flanges of the steel pipes abut against each other .   The steel pipe joint structure for a steel slit dam according to claim 1, wherein the one flanged steel pipe is an annular or disk-shaped flanged steel pipe protruding outward from the steel pipe. In the flanged steel pipe joint structure of the steel slit dam installed between the concrete embankments on both banks in the cross direction of the river,
  At the joint end of one flanged steel pipe, a tenon member smaller in diameter than the steel pipe insertable into the other flanged steel pipe is inscribed on the inner surface of the joint end of the one flanged steel pipe. The protruding part of the tenon member is inserted into the other flanged steel pipe, and the flanges of the steel pipes to be joined are flange-joined in a state where the flanges of the steel pipes are joined to each other. A steel pipe joint structure of a steel slit dam. In a steel pipe joint structure with a flange of a steel slit dam installed between concrete embankments on both banks in the transverse direction of the river,
Joint end portion of one of the flanged steel pipe is greater diameter steel pipe than the other flanged steel pipe is found attached integrally, the joint end portion of the other flanged steel tubes, a portion of the inner than the edge An annular flange is provided externally, and a steel pipe projecting outward from the annular flange is inserted into the enlarged steel pipe of the one flanged steel pipe, and the flanges of the steel pipes to be joined are brought into contact with each other. A steel pipe joint structure of a steel slit dam characterized by being flanged. In a steel pipe joint structure with a flange of a steel slit dam installed between concrete embankments on both banks in the transverse direction of the river,
A steel pipe joint for a steel slit dam, wherein one of the flanged steel pipes and the other flanged steel pipe are flange-joined together through an inner sleeve member having an annular flange externally provided at the center. Construction. The two flanged steel pipes each have an annular flange projecting inward and outward of the steel pipe, a keyway is formed in the inward projection, and the inner sleeve member is large enough to be inserted into the annular flange of the steel pipe. A key is externally provided at both ends in the pipe axis direction, and the key inserted into the key groove is rotated so as to be in a state where it cannot be pulled out, and is flange-joined. 5. The steel pipe joint structure of the steel slit dam described in 5 . The steel slit according to any one of claims 1 to 6 , wherein a protective casing that covers the flange joint is provided on an outer peripheral surface of a flange of the one or other flanged steel pipe. Dam steel pipe joint structure.

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