Method for constructing a dam and formwork usable in the method

Abstract

To provide a dam construction method capable of accurately constructing an arch-shaped dam, and a form usable for the dam construction method.SOLUTION: The dam construction method M1 includes a base section construction step ST10 for constructing a plurality of base sections, an arch member forming step ST20 for forming an arch member by welding a flange to an end portion of each of a plurality of fourth steel pipes, and a dam construction step ST10 for connecting the arch member to each of a plurality of third steel pipes in each of the plurality of base sections constructed by the base section construction step ST30, wherein the flange is obliquely welded to the end portion of the fourth steel pipe in the arch member forming step ST20.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a dam construction method and a formwork that can be used in the dam construction method. [Background technology]

[0002] They are placed in rivers to block large rocks and driftwood that may be involved in debris flows caused by heavy rain. Such dams are known as dams that protrude upstream of a river when viewed vertically. A dam formed in an arch shape (hereinafter referred to as an "arch dam") is known. (See, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 01-111727 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention relates to a dam construction method that can construct an arch-shaped dam with high precision, and the dam construction method. One of the objectives is to provide a formwork that can be used in this construction method. [Means for solving the problem]

[0005] (1): The present invention is a dam formed so as to protrude upstream of a river when viewed vertically. A method for constructing a dam, the dams each having a first dam extending in a first direction. a first steel pipe and a plurality of second steel pipes extending in a second direction perpendicular to the first direction and intersecting the first steel pipe; a second steel pipe extending in a third direction perpendicular to the first direction and the second direction and and a plurality of third steel pipes intersecting the second steel pipes, Each of the plurality of third steel pipes is located on a plane defined by the second direction and the third direction. A plurality of fourth steel pipes connected to the third steel pipe and extending obliquely with respect to the longitudinal direction of the third steel pipe; The dam construction method includes a base portion construction step of constructing the plurality of base portions; an arch member forming process in which flanges are welded to the ends of the fourth steel pipe to form arch members; the plurality of base portions in each of the plurality of base portions constructed by the base portion construction step, and a dam construction step of connecting the arch members to each of the third steel pipes, In the forming step, a flange is attached to the end of the fourth steel pipe at an angle to the longitudinal direction of the fourth steel pipe. or in the base construction step, a flange is welded to the end of the third steel pipe. 3 Weld at an angle to the longitudinal direction of the steel pipe.

[0006] (2): In the dam construction method of (1), the base construction step is performed by marking the marking line. It may also be performed on a surface plate.

[0007] (3): In the dam construction method of (1) or (2), in the arch material forming step, a step of welding a flange to the end of the fourth steel pipe at an angle to the longitudinal direction of the fourth steel pipe; In the base construction step, a flange is attached to the end of the third steel pipe in the longitudinal direction of the third steel pipe. Each of the steps of welding obliquely to the other may be performed using a predetermined formwork.

[0008] (4): In the dam construction method of (3), the predetermined formwork comprises a base plate and a steel pipe support portion attached to a plate and capable of supporting a steel pipe parallel to the base plate; and an inclined plate erected at an angle from the front of the steel pipe supported by the steel pipe support portion. The inclined plate is provided so as to face the end of the steel pipe, and the end of the steel pipe is welded to the inclined plate. The flange may have a hole formed therein that communicates with a hole formed in the flange.

[0009] (5): In the dam construction method of (4), the steel pipe support parts are arranged at predetermined intervals. Each of the plurality of plate-like members has a straight edge that is equal to or larger than the diameter of the steel pipe. A semicircular recess having a diameter may be formed.

[0010] (6): In the dam construction method of (5), from the inner peripheral surface of the plate-like member that defines the recess A plurality of protrusions may protrude from the inner peripheral surface to support the steel pipe at a distance from the inner peripheral surface.

[0011] (7): The present invention is a dam formed so as to protrude upstream of a river when viewed vertically. A form for welding flanges to steel pipes, comprising a base plate and a flange attached to the base plate. a steel pipe support part that can support a steel pipe parallel to the base plate; and an inclined plate provided obliquely upright, the inclined plate being configured to support the steel pipe supported by the steel pipe support portion. The inclined plate is provided so as to face the end of the steel pipe. A hole is formed in the flange, which hole communicates with the hole formed in the flange.

[0012] (8): In the formwork of (7), the steel pipe support portion is a plurality of steel pipes arranged at predetermined intervals. Each of the plurality of plate-like members has a diameter equal to or greater than the diameter of the steel pipe. A semicircular recess may be formed.

[0013] (9): In the mold of (8), from the inner peripheral surface of the plate-like member defining the recess, A plurality of protrusions may protrude from the inner peripheral surface to support the steel pipe at a distance from the inner peripheral surface. [Effects of the Invention]

[0014] According to the present invention, a dam construction method that can construct an arch-shaped dam with high precision and the method Formwork is provided that can be used in a dam construction method. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a diagram illustrating a dam according to an embodiment of the present invention; [Figure 2] FIG. 2 is a perspective view showing a base portion of the dam shown in FIG. 1. [Figure 3] 2A and 2B are front views showing arch members provided in the dam shown in FIG. 1, where FIG. 2A shows the arch member on the upstream side, and FIG. 2B shows the arch member on the downstream side. [Figure 4] FIG. 10 is a plan view showing how the arch material is joined to the base portion. [Figure 5] FIG. 1 is a flow chart showing an example of a dam construction method according to an embodiment of the present invention. [Figure 6] FIG. 6 is a plan view showing a marking step in the dam construction method shown in FIG. 5. [Figure 7] FIG. 9 is a front view of the jig shown in FIG. 8. [Figure 8] FIG. 6 is a plan view showing a first steel pipe placement step in the dam construction method shown in FIG. 5. [Figure 9] FIG. 6 is a plan view showing a second steel pipe arranging step and a first welding step in the dam construction method shown in FIG. 5. [Figure 10] FIG. 6 is a plan view showing a rotation step in the dam construction method shown in FIG. 5. [Figure 11] FIG. 6 is a plan view showing a third steel pipe arranging step and a second welding step in the dam construction method shown in FIG. 5. [Figure 12]FIG. 6 is a front view showing an example of a formwork used in the dam construction method shown in FIG. 5. [Figure 13] FIG. 13 is a plan view of the formwork shown in FIG. [Figure 14] 13 is a view of the formwork shown in FIG. 12 as viewed from the base of the arrow shown in FIG. 12 toward the tip of the arrow. [Figure 15] FIG. 6 is a front view showing a flange arrangement step in the dam construction method shown in FIG. 5. [Figure 16] FIG. 6 is a front view showing a steel pipe arranging step and a flange welding step in the dam construction method shown in FIG. 5. [Figure 17] FIG. 10 is a flow chart showing a dam construction method according to a modified example of the present invention. [Figure 18] FIG. 18 is a front view showing a steel pipe arranging step and a flange welding step in the dam construction method shown in FIG. 17. [Figure 19] FIG. 18 is a front view showing an arch material formed by the arch material forming step of the dam construction method shown in FIG. 17. DETAILED DESCRIPTION OF THE INVENTION

[0016] The following describes a method for constructing a dam according to the present invention and a formwork that can be used for the method. The following exemplary embodiments are provided to facilitate understanding of the present invention. The present invention is not intended to limit the scope of the present invention. The following embodiments may be modified or improved without departing from the spirit of the present invention. In the accompanying drawings, the dimensions of each component have been exaggerated or reduced in order to facilitate understanding. In some cases, hatching may be omitted.

[0017] FIG. 1 is a diagram schematically illustrating a dam according to an embodiment. As shown in FIG. 1, the dam 1 includes: Upstream in the river flow direction (hereinafter referred to as "flow direction RF") as viewed vertically It is formed so as to protrude to the side UF, and is configured as a so-called arch dam. 1 comprises a plurality of base portions 10 and a plurality of arch members 20. The plurality of arch members 20 are In the flow direction RF, a plurality of upstream arch members 21 are arranged on the upstream side UF, and a downstream and a plurality of downstream arch members 22 disposed in the DF.

[0018] FIG. 2 is a perspective view showing any one of the plurality of base portions 10. Each of the base portions 10 has substantially the same configuration. Each of the body parts 10 includes one first steel pipe 11 and a plurality of (two in this embodiment) second steel pipes. 12, a plurality of (four in this embodiment) third steel pipes 13, and a plurality of (the base portion 10 shown in FIG. 2 In this embodiment, the flanges FL are disc-shaped. The flange FL is a metal plate, and in the vicinity of the outer edge thereof, That is, through holes (hereinafter referred to as "flange holes FLH") are formed at intervals of substantially 90°. It has been done.

[0019] In this specification, the terms "substantially equally spaced" and "substantially equal" include manufacturing errors. This includes cases where the intervals are not equal or equidistant within the range that can be recognized.

[0020] In this embodiment, the first steel pipe 11, the second steel pipe 12, and the third steel pipe 13 are made of the same material. However, the first steel pipe 11, the second steel pipe 12, and The steel pipes 13 may be made of different materials and may have different dimensions. In the embodiment, each of the plurality of flanges FL is formed of the same material and has the same size and shape. and has flange holes FLH of the same size and number (four in this embodiment) However, if the flange holes FLH can communicate with each other, each of the multiple flanges FL , they do not have to be made of the same material or have the same size and shape.

[0021] The first steel pipe 11 extends in a first direction X. When the dam 1 is constructed, the first direction X is In the base portion 10 shown in FIG. 2, both ends of the first steel pipe 11 in the first direction X correspond to the vertical direction. At the end of the first steel pipe 11 (upper and lower sides), a flange FL is provided in the longitudinal direction (first direction) of the first steel pipe 11. However, in the other base portion 10, one side (upper side) of the first steel pipe 11 is welded vertically. ) end and the other (lower) end, a flange FL may be welded to only one of them.

[0022] The second steel pipe 12 extends in a second direction Y perpendicular to the first direction X and intersects with the first steel pipe 11. When the dam 1 is constructed, the second direction Y corresponds approximately to the flow direction RF. One of the steel pipes 12 intersects with one side (upper side) of the first steel pipe 11, and the other The first steel pipe 11 intersects with the other side (lower side) of the first steel pipe 11. One end of the second steel pipe 12 is welded to the first steel pipe 11, and the other end of the second steel pipe 12 is welded to the first steel pipe 11. A flange FL is welded to the second steel pipe 12 perpendicularly to the longitudinal direction (second direction Y) of the second steel pipe 12. are.

[0023] The third steel pipe 13 extends in a third direction Z perpendicular to both the first direction X and the second direction Y. When the dam 1 is constructed, the third direction Z is approximately The first direction X corresponds to the direction crossing the river (hereinafter referred to as "crossing direction RC"). In this case, two of the four third steel pipes 13 are connected to the first steel pipe 11 at one side (upper side) of the first steel pipe 11. The other two intersect the first steel pipe 11 and the second steel pipe 12, and the other two intersect the other side (lower side) of the first steel pipe 11. The first steel pipe 11 and the second steel pipe 12 intersect at this portion.

[0024] By the way, when looking from the upstream side UF to the downstream side DF, the left side in the transverse direction RC is simply The left side is sometimes referred to as the "left" or "left side," and the right side is sometimes simply referred to as the "right" or "right side." As shown in FIG. 2, one of the two upper third steel pipes 13 is in the third direction Z. The other of the two third steel pipes 13 on the upper side is the third steel pipe 11. It is on the other side (right side) of the first steel pipe 11 in the Z direction. One of the third steel pipes 13 is on one side (left side) of the first steel pipe 11 in the third direction Z. The other of the two lower third steel pipes 13 is inclined relative to the first steel pipe 11 in the third direction Z. The two third steel pipes 13 are on the left side of the first steel pipe 11. In each of the three third steel pipes, the end on the other side (the first steel pipe 11 side) is welded to the first steel pipe 11. At the end of one side (opposite to the first steel pipe 11 side), a flange FL is connected to the third steel pipe. The pipes 13 are welded perpendicular to the longitudinal direction (third direction Z). In each of the two third steel pipes 13 on the right side of the first steel pipe 11, The end of the first steel pipe 11 is welded to the first steel pipe 11. At the end of the third steel pipe 13 (opposite to the end of the third steel pipe 13), a flange FL is provided in the longitudinal direction (third direction Z) of the third steel pipe 13. The metal is welded vertically.

[0025] Returning to FIG. 1, attention is focused on an arbitrary one of the base portions 10A on the upstream side of the base portion 10. Then, each of the two second steel pipes 12 of the base portion 10 (base portion 10A) is connected to the downstream DF. The two second steel pipes 12 of a certain base portion 10 (for example, the base portion 10B) are connected to each other. Specifically, the flange welded to the end of the downstream side DF of the second steel pipe 12 of the base portion 10A The flange hole FLH of the flange FL is welded to the end of the upstream side UF of the second steel pipe 12 of the base portion 10B. The second steel pipe 12 of the base portion 10A is connected to the flange hole FLH of the flange FL. and the second steel pipe 12 of the base portion 10B are butted together, and the flange holes FLH, FLH are connected. The second steel pipe 12 of the base portion 10A and the second steel pipe 12 of the base portion 10B are bolted together via the As a result, the base portion 10A and the base portion 10B are connected to each other.

[0026] In addition, the first steel pipe 11 of the base portion 10 (base portion 10A) is connected to the lower side of the base portion 10 (for example , the base portion 10C) is connected to the first steel pipe 11. Specifically, the first steel pipe 11 of the base portion 10A The flange hole FLH of the flange FL welded to the lower end of the pipe 11 and the first hole of the base portion 10C 1 The flange FL is welded to the upper end of the steel pipe 11 so as to communicate with the flange hole FLH of the flange FL. The first steel pipe 11 of the base portion 10A and the first steel pipe 11 of the base portion 10C are butted together, and are in communication with each other. The first steel pipe 11 of the base portion 10A and the second steel pipe 12 of the base portion 10C are connected through the flange holes FLH, FLH. The base portion 10A and the base portion 10C are connected by bolting the steel pipe 11 to the base portion 10A. It is being done.

[0027] FIG. 3(A) is a front view showing one of the upstream arch members 21 (as seen from the upstream side UF). 3(A) and 3(B) are front views showing one of the downstream arch members 22. As shown in 3(B), the upstream arch member 21 and the downstream arch member 22 are Except that the longitudinal length of 21 is longer than the longitudinal length of downstream arch member 22. The upstream arch member 21 has a steel pipe 23 and a longitudinal direction of the steel pipe 23. The downstream arch member 22 includes flanges FL welded to both ends. The shortest steel pipe 25 and flanges FL welded to both ends of the steel pipe 25 in the longitudinal direction. Hereinafter, the steel pipes 23 and 25 that constitute the arch member 20 will be referred to as the "fourth steel pipe 24." The flanges FL welded to both ends of the fourth steel pipe 24 are The angle α is inclined at a predetermined angle α (0°<α<90°) with respect to the longitudinal direction of the 4. There are no particular limitations on the angle, but it may be, for example, about 85°.

[0028] In this embodiment, the fourth steel pipe 24 is connected to the first steel pipe 11, the second steel pipe 12, and the third steel pipe 13. The first steel pipe 11, the second steel pipe 12, and the third steel pipe 13 are made of the same material and have the same outer periphery. However, the fourth steel pipe 24 has a diameter and an inner diameter. It may be made of a different material from the third steel pipe 13 and may have a different outer diameter and inner diameter.

[0029] FIG. 4 is a plan view (vertically upper side) showing how the arch member 20 is joined to the base portion 10. As shown in FIG. 4, each of the plurality of arch members 20 is oriented in the transverse direction R At C, the arch members 20 are connected to the base members 10 on both sides of the arch members 20. The flange hole FLH of the flange FL welded to the left end of the arch member 20 and the flange hole FLH of the arch member 20 The flange FL is welded to the right end of the third steel pipe 13 of the base portion 10, which is located on the left side of the The third steel pipe 13 and the fourth steel pipe 24 of the arch member 20 are connected to each other so that the flange hole FLH is in communication with the third steel pipe 13. The third steel pipe 13 and the fourth steel pipe 24 are butted together and connected through the flange holes FLH, FLH. By connecting the arch member 20 and the left side of the arch member 20, The arch member 20 is connected to the base member 10. The flange hole FLH of the FL and the third steel pipe 1 of the base part 10 on the right side of the arch member 20 3 so that the flange hole FLH of the flange FL welded to the left end of the flange 3 communicates with the flange hole FLH of the flange FL. The steel pipe 13 and the fourth steel pipe 24 of the arch member 20 are butted together, forming a flange hole FLH. The third steel pipe 13 and the fourth steel pipe 24 are bolted together via the FLH, forming an arch. The arch member 20 is connected to the base portion 10 on the right side of the arch member 20.

[0030] As described above, the flanges FL welded to both ends of the fourth steel pipe 24 are The angle α is inclined at a predetermined angle α (0°<α<90°) relative to the hand direction. 4, the flange FL of the arch member 20 is connected to the flange FL of the third steel pipe 13. By joining the plurality of arch members 20, each of the plurality of arch members 20 is aligned in the longitudinal direction of the second steel pipe 12 (the Located on a horizontal plane defined by the longitudinal direction of the third steel pipe 13 (third direction Z) and the second direction Y. At the same time, it extends at an angle to the transverse direction RC, and when viewed from the vertical direction, The dam 1 protruding toward F is constructed. Specifically, the dam 1 is constructed on the upstream side UF and the downstream side DF. In the cross direction RC, the base portion 10 (for example, the upstream side U shown in FIG. 1) is located at the center. The base portion 10D of the downstream side DF shown in FIG. 1 and the base portion 10E of the downstream side DF protrude into the upstream side UF. In the dam 1, each of the plurality of fourth steel pipes 24 is 3 extends obliquely with respect to the longitudinal direction of the steel pipe 13.

[0031] As described above, the steel pipe 23 located on the upstream side UF of the fourth steel pipe 24 is Since the steel pipe 25 in the downstream DF is longer than the steel pipe 25 in the downstream DF, the dam 1 is longer than the steel pipe 25 in the upstream U when viewed vertically. The width (length in the transverse direction RC) increases as the distance to F increases, forming a fan-shaped structure.

[0032] Such an arch-shaped dam 1 is constructed with high precision by the dam construction method described below. .

[0033] FIG. 5 is a flow chart showing an example of a dam construction method according to an embodiment. The dam construction method M1 includes a base construction step ST10, an arch member formation step ST20, and a dam construction step ST10. 5, for convenience, the base portion construction step ST10 is followed by the a Although the step ST20 of forming the arch material is shown to be performed, the step ST10 of constructing the base and the step ST20 of forming the arch material are not shown. The arch material forming step ST20 may be performed simultaneously with the arch material forming step ST20, or may be performed after the arch material forming step ST20. A body construction step ST10 may be performed.

[0034] The base part construction step ST10 is a step of constructing the above-mentioned plurality of base parts 10. As shown in the figure, the base construction process ST10 includes a marking process ST11 and a first steel pipe placement process ST1. 2, a second steel pipe arrangement process ST13, a first welding process ST14, a rotation process ST15, and The process includes a third steel pipe arrangement step ST16 and a second welding step ST17.

[0035] FIG. 6 is a plan view (viewed from above in the vertical direction) showing the state of the scoring step ST11. As shown in FIG. 6, in the marking step ST11, a predetermined marking line 1001 is drawn on a surface plate 1000. In FIG. 6, the scribing line 1001 is shown as a dashed line. Therefore, the surface plate 1000 has, for example, a plurality of parallel extending portions (in this embodiment) extending in the vertical direction. In this embodiment, three vertical bands 1010, 1011, 1012 and horizontal bands parallel to each other A goto formed by a plurality of (two in this embodiment) extending horizontal bands 1021, 1022. A pattern of scribed lines may be drawn. Note that the scribed line pattern shown in FIG. 6 is an example. However, the present invention is not limited to such a pattern.

[0036] The vertical bands 1010, 1011, and 1012 are drawn at equal intervals in the horizontal direction. In the direction, the vertical band 1011 is between the vertical bands 1010 and 1012. The vertical lengths of the vertical bands 1010 and 1012 are the same length VL. The vertical ends of the vertical bands 1010, 1011, 1012 are aligned. The length VL of the horizontal band 012 in the vertical direction is equal to the length of the first steel pipe 11 (length in the first direction X). The horizontal lengths of 1020 and 1021 are the same, WL1. 1 is a marking line for marking the vertical band 1010, from the marking line 1000A on the vertical band 1011 side to the vertical band 1012 side. The length of the marking line for marking the band 1012 is up to the marking line 1000B on the vertical band 1011 side. The distance WL1 (see Figure 1) between the first steel pipe 11 of the upstream UF and the first steel pipe 11 of the downstream DF Also, the horizontal length of each of the vertical bands 1010, 1011, and 1012 (vertical The width of the horizontal bands 1020 and 1021 are equal in length to each other. The width W is the width of the first steel pipe 11, the second steel pipe 12, the third steel pipe 13, and the fourth steel pipe The outer diameter of the first steel pipe 11, the second steel pipe 12, and the outer diameter of the second steel pipe 13 are the same as those of the first steel pipe 11 and the second steel pipe 14. 2, the third steel pipe 13, and the fourth steel pipe 24 may be collectively referred to simply as "steel pipes."

[0037] In this embodiment, in the marking step ST11, the vertical bands 1010 and 1012 are Near both ends in the longitudinal direction of each of the horizontal bands 1020 and 1021, and in the longitudinal direction of each of the horizontal bands 1020 and 1021 Jigs 1030 are placed near both ends of the substrate.

[0038] 7 is a front view showing the jig 1030. As shown in FIGS. The jig 1030 is, for example, a metal member having an H-shape when viewed from the front. A plate-shaped horizontal plate portion 1031 is arranged parallel to the surface plate 1000, and two plates are connected to both ends of the horizontal plate portion 1031. A pair of plate-like upright portions 1032, 1033 are connected to the horizontal plate portion 1031 and are provided perpendicular to the horizontal plate portion 1031. In the longitudinal direction of the standing portion 1032, the horizontal plate portion 1031 is 32 is connected to a portion slightly lower than the center (closer to the surface plate 1000). The portion where the horizontal plate portion 1031 and the standing portion 1032 are connected is the connecting portion 1033. 32, an upper portion 1032A above the connection portion 1033 (the side farther from the surface plate 1000) The length H1 is longer than the radius R of the steel pipe. For convenience, the steel pipe is shown by a broken line in Figure 7. The length of the horizontal plate portion 1031 is set to be substantially equal to the diameter 2R of the steel pipe and the width W described above. equal.

[0039] In the marking step ST11, as shown in FIG. 6, the vertical band 1010 of the plurality of jigs 1030 is , 1012 is set on the marking line for marking the vertical bands 1010, 1012. The horizontal bands 1020, The jig 1030 placed in 1021 is set upright on the marking line for marking the horizontal bands 1020 and 1021. The part 1032 is arranged along the line.

[0040] Next, the first steel pipe arrangement step ST12 is performed. FIG. 8 shows the first steel pipe arrangement step ST12. As shown in FIG. 8, the first steel pipe placement step S In T12, a pair of upright portions 1032 of a jig 1030 arranged on the vertical bands 1010 and 1012 The first steel pipe 11 is placed between the upper portions 1032A of the first steel pipe 11. Two jigs 1030 are supported directly above the vertical band 1010, and the other first steel pipe is The vertical band 1012 is supported by a jig 1030 directly above the vertical band 1012.

[0041] In the example of FIG. 8, the first steel pipe 11 to be subjected to the first steel pipe placement step ST12 has both ends The flange FL is welded in advance perpendicular to the longitudinal direction of the first steel pipe 11. A flange FL may be welded to the first steel pipe 11 after the placement step ST12.

[0042] As described above, the vertical length VL of the vertical bands 1010 and 1012 is equal to the length of the first steel pipe 11. In addition, both ends of the vertical bands 1010 and 1012 in the vertical direction are aligned. Therefore, both ends of one first steel pipe 11 are positioned directly above both ends of the vertical band 1010. One first steel pipe 11 is placed directly above the vertical band 1010, and both ends of the other first steel pipe 11 are The other first steel pipe 11 is connected to the vertical band 101 so as to be positioned directly above both ends of the vertical band 1012. By placing the first steel pipe 11 directly above the second steel pipe 2, the positions of both ends of the two first steel pipes 11, 11 are completely aligned. In this state, the two first steel pipes 11, 11 can be arranged with a gap WL1 between them. As described above, the interval WL1 is the distance from the first steel pipe 11 of the upstream UF to the downstream D Equal to the distance to the first steel pipe 11 of F.

[0043] Next, a second steel pipe arrangement step ST13 and a first welding step ST14 are performed. FIG. 10 is a plan view showing the arrangement step ST13 and the first welding step ST14 (as seen from above in the vertical direction). As shown in FIG. 9, in the second steel pipe placement step ST13, The second steel pipe 12 is placed. Note that one of the second steel pipes 12 to be subjected to the second steel pipe placement step ST13 is A flange FL is welded to the end of the second steel pipe 12 perpendicular to the longitudinal direction of the second steel pipe 12 in advance. The end portion 12E on the other side is machined into a shape that fits the curved surface of the first steel pipe 11.

[0044] In the second steel pipe arrangement step ST13, the jig 10 arranged on the vertical band 1010 side of the horizontal band 1020 The first second steel pipe 12 is disposed between the upper portions 1032A of the pair of upright portions 1032 of the pipe 30. , on a pair of upright portions 1032 of a jig 1030 arranged on the vertical band 1012 side of the horizontal band 1020 The second steel pipe 12 is disposed between the side portions 1032A. Between the upper portions 1032A of the pair of upright portions 1032 of the jig 1030 arranged on the O10 side The third second steel pipe 12 is placed, and the jig 103 placed on the vertical band 1012 side of the horizontal band 1021 is The fourth second steel pipe 12 is placed between the upper portions 1032A of the pair of upright portions 1032 of 0. In this way, the first second steel pipe 12 is cut by one jig 1030 from directly above the horizontal band 1020. The second steel pipe is supported on the side of the vertical band 1010 by one jig 1030. 20 and on the side of the vertical band 1012. Also, the third second steel pipe 12 is supported by one jig. 1030 is supported directly above the horizontal band 1021 and on the vertical band 1010 side, and the fourth second steel pipe is supported by one jig 1030 directly above the horizontal band 1021 and on the vertical band 1012 side.

[0045] Here, the length WL2, which is half the length WL1 of the horizontal strips 1020 and 1021, is the length of the second steel strip. The flange FL welded to the pipe 12 is connected to the end 12E of the second steel pipe 12 (the bend of the first steel pipe 11). The length is substantially equal to the length of the end (the end processed to fit the surface). By disposing two second steel pipes 12 directly above the horizontal band 1020, One end 12E of the two second steel pipes 12 arranged in the vertical band 1010 is arranged on the vertical band 1010. The first steel pipe 11 is arranged along the outer peripheral surface of the first steel pipe 11, and the two second steel pipes 11 arranged on the horizontal band 1020 are arranged along the outer peripheral surface of the first steel pipe 11. The other end 12E of the second steel pipe 12 is connected to the first steel pipe 11 arranged on the vertical band 1012. and two second steel pipes arranged on the horizontal band 1020. The flanges FL of the 12 are butted against each other in a state of substantial contact. By arranging the two second steel pipes 12 directly above the horizontal band 1021 as described above, One end 12E of the two second steel pipes 12 arranged on the band 1021 is connected to the vertical band 101 2, and is arranged along the outer peripheral surface of the first steel pipe 11 arranged on the horizontal band 1021. The other end 12E of the two second steel pipes 12 was placed on the vertical band 1012. The first steel pipe 11 is arranged along the outer peripheral surface thereof, and the second steel pipe 11 is arranged on the horizontal band 1021. The flanges FL of the two second steel pipes 12 are butted together in a state of substantial contact with each other. In this way, the four second steel pipes 12 are positioned at desired positions with high precision.

[0046] Next, a first welding step ST14 is performed. In this first welding step ST14, as shown in FIG. The end 12E of the second steel pipe 12 is welded to the outer circumferential surface of the first steel pipe 11. As a result, a plurality of welded bodies 50 in which two second steel pipes 12 are welded to a first steel pipe 11 are formed at once. FIG. 9 shows an example in which two weldments 50 are formed at once.

[0047] Next, the rotation step ST15 is performed. FIG. 10 is a plan view (a plan view of the lead frame) showing the state of the rotation step ST15. As shown in FIG. 10, in the rotation step ST15, the first welding Each of the two welded bodies 50 formed in step ST14 is separated from the vertical bands 1010 and 1012. The second steel pipe 12 of the welded body 50 is rotated by 90° while being prevented from shifting. The pipe 11 extends vertically upward.

[0048] In this embodiment, the vertical band 1011 is also provided with two vertical bands in the same manner as the vertical bands 1010 and 1012. In this embodiment, the additional portion 1020E of the horizontal band 1020 is placed. The additional portion 1021E of the horizontal band 1021 is positioned on the opposite side of the vertical band 1010 from the vertical band 1011 side. The vertical band 1011 is marked on the side opposite to the vertical band 1012. In place of the jig 1030, the jig 1040 is used to attach the horizontal bands 1020, 1021 and the additional portion 1020E. , 1021E. The jig 1040 has a length that is, for example, about half that of the jig 1030. 10, the horizontal band 1020, Two jigs 1040 are arranged between the vertical bands 1010 and 1011 of the 1021, Two jigs 104 are provided between the vertical bands 1011 and 1012 of the horizontal bands 1020 and 1021. 0 is arranged, and one jig 1 is arranged at each of the additional parts 1020E and 1021E on the vertical band 1010 side. 040 is arranged, and one fixation is arranged in each of the additional parts 1020E and 1021E on the vertical band 1012 side. Although an example in which the jig 1040 is arranged is shown, the arrangement of the jig 1040 is not limited to this. It is not something that can be done.

[0049] Next, a third steel pipe arrangement step ST16 and a second welding step ST17 are performed. FIG. 10 is a plan view showing the state of the pipe arrangement step ST16 and the second welding step ST17 (as viewed from above in the vertical direction). (Figure below).

[0050] As shown in FIG. 11, in the third steel pipe arrangement step ST16 of this embodiment, first, the vertical belt 101 The welding body 50 rotated by 90° is also placed on the vertical band 1011. The welded body 5 rotated by 90° is placed between a pair of upright portions 1032 of each of the jigs 1030. At this time, the first steel pipe 11 of the welded body 50 is positioned so that it is not positioned so as to come into contact with the vertical band 1011. In this way, the three weldments 50 are precisely aligned. It is often placed on a surface plate 1000.

[0051] In the third steel pipe arrangement step ST16 of this embodiment, the third steel pipe 13 is then placed on the surface plate 1000. The third steel pipe 13 to be placed in the third steel pipe placement step ST16 has one end The flange FL is welded in advance perpendicular to the longitudinal direction of the third steel pipe 13, and the other end 13 E is processed into a shape that follows the curved surface of the first steel pipe 11. The third steel pipe 1 is attached to each of the jigs 1040 arranged in the additional portions 1020E and 1021E. The third steel pipe 13 is placed so that the end 13E of the third steel pipe 13 is in contact with the first steel pipe 11. The outer peripheral surface of the first steel pipe 11 arranged in the band 1010 is connected to the first steel pipe 11 arranged in the vertical band 1011. the distance from the outer surface of the first steel pipe 11 arranged in the vertical band 1012 to the outer surface of the first steel pipe 11 arranged in the vertical band 1012 The distance between the first steel pipe 11 and the outer surface of the first steel pipe 11 is equal to the distance WL3, and the distance W Half the length of L3 is the distance from the flange FL welded to the third steel pipe 13 to the end of the third steel pipe 13. The length is substantially equal to the length of the end 13E (the end processed into a shape that fits the curved surface of the first steel pipe 11). Therefore, between the first steel pipes 11, 11 arranged in the vertical bands 1010, 1011, By placing two third steel pipes 13 directly above each of the horizontal bands 1020 and 1021, The flanges FL of the two third steel pipes 13 are pushed together while substantially in contact with each other. Similarly, the first steel pipes 11, 1012 arranged in the vertical bands 1011, 1012 are joined together. Two third steel pipes 13 are placed directly above each of the horizontal bands 1020, 1021 between the first and second steel pipes 1020, 1021. As a result, the flanges FL of the two third steel pipes 13 are in substantial contact with each other. In this way, the plurality of third steel pipes 13 (12 in the example of FIG. 11) are butted together at the desired positions. are positioned with high precision.

[0052] Next, a second welding step ST17 is performed. In this second welding step ST17, The end 13E of the third steel pipe 13 arranged as above is welded to the outer circumferential surface of the first steel pipe 11. As a result, the base portion 10 (see FIG. 2) in which the four third steel pipes 13 are welded to the welded body 50 is collectively welded. FIG. 11 shows an example in which three base parts 10 are constructed at once. There are.

[0053] In this manner, in this embodiment, the base portion construction step ST10 is performed by drawing the marking line 1001. However, the base part construction step ST10 is carried out on the surface plate 1000 in such a manner that the marking line 1001 is not marked. However, it is not essential to perform the base part construction step ST10 on the surface plate 1000. By performing the process on a surface plate 1000 on which feed lines 1001 are drawn, the plurality of base parts 10 can be precisely Not only can it be constructed efficiently, but it can also construct a plurality of base parts 10 with high precision at once. do.

[0054] Next, the arch member forming step ST20 will be described.

[0055] In the arch member forming step ST20, a flange FL is welded to the end of the fourth steel pipe 24 to form the arch member. As shown in FIG. 5, the arch member forming step ST20 is a process of forming a formwork. Step ST21, flange placement step ST22, steel pipe placement step ST23, flange welding The process includes step ST24.

[0056] In the arch member forming step ST20, first, a formwork preparing step ST21 is performed. In the form preparation step ST21, a form 2000 shown in FIGS. 12 to 14 is prepared. FIG. 13 is a plan view of the formwork 2000 (viewed from above in the vertical direction); 14 is a diagram showing the formwork 2000 from the base of the arrow shown in FIG. 12 toward the tip of the arrow. As shown in FIGS. 12 to 14, the formwork 2000 includes a base plate 2001 and A steel pipe support portion 2010, a pair of inclined plates 2003, 2003, and four support plates 2004 The base plate 2001 is a plate-like member that is rectangular when viewed in the vertical direction.

[0057] The steel pipe support portion 2010 includes a plurality of plate-like members 2002. In this embodiment, the steel pipe The support portion 2010 is provided on one side and the other side of the center of the long side direction LS of the base plate 2001. Each of the pair of plate-like members 2002, 2002 is provided. The pair of plate-like members 2002, 2002 are arranged at a predetermined interval in the long side direction LS. The pair of plate-like members 2002, 2002 have the same configuration, but for the sake of convenience, The plate-like member 2002 provided on one side of the center of the base plate 2001 in the long side direction is called a "plate-like member." The plate-shaped member 2002 provided on the other side is referred to as "plate-shaped member 2002A." Each of the pair of (plural) plate-like members 2002, 2002 is 12 and the plan view of FIG. 13, the plate-like member 20 Each of the 2002 and 2002 extends over the entire length of the base plate 2001 in the short side direction SS. As shown in FIG. 14, the slits are arranged in the short side direction SS. A semicircular recess 2011 is formed in the center of the plate-like member 2002. 11 is the above-mentioned steel pipe (first steel pipe 11, second steel pipe 12, third steel pipe 13, and fourth steel pipe 24) In this embodiment, the above-mentioned steel pipes (first steel pipe 11, second steel pipe 12, The third steel pipe 13 and the fourth steel pipe 24 have a larger diameter than each other.

[0058] As shown in FIGS. 13 and 14, the inner circumferential surface 2 of the plate-like member 2002 defining the recess 2011 A plurality of (two in this embodiment) protrusions 2013, 2013 protrude from the surface 012. The protrusions 2013, 2013 are formed near the bottom 2012B of the inner circumferential surface 2012, In this embodiment, an imaginary line passing through the bottom portion 2012B and the center C of the circle that defines the inner circumferential surface 2012 is As shown in FIG. The protrusion 2013 has a substantially triangular cross section with an acute angle at the apex 2013T. The protrusion 2013 is inclined toward the center C. That is, the inclination direction of the protrusion 2013 is the same as that of the inner peripheral surface 2012. The apex 2 of the pair of protrusions 2013, 2013 is substantially parallel to the radial direction of the circle. 013T, 2013T are steel pipes (No. 1 steel pipe 11, No. 2 steel pipe 12, No. 3 steel pipe 13, and No. 4 steel pipe The steel pipe 24 is located approximately on a circle that defines the outer periphery of the steel pipe. The fourth steel pipe 24 is shown by a broken line as a representative of the pipe. The angle θ with the center C of the gap as the reference is the angle between the pair of convex portions 2013, 2013 and the bottom portion 2012B. From the viewpoint of providing the device close to the surface, the angle may be, for example, 10° or more and 30° or less.

[0059] As shown in FIGS. 12 to 14, the pair of inclined plates 2003, 2003 is The inclined plates 2 are provided on one side and the other side of the center of the long side direction LS. 003 is a plate-like member inclined at a predetermined angle α with respect to the base plate 2001. The swash plates 2003, 2003 have the same configuration except for the tilting direction, as will be described later. For convenience, the inclined plate 2003 provided on one side of the center in the long side direction LS is referred to as the "inclined plate 20 The inclined plate 2003 provided on the other side is described as "inclined plate 2003B." This may happen.

[0060] The formwork 2000 of this embodiment is provided with a pair of inclined plates 2003, 2003. In another example, only one of the inclined plate 2003A and the inclined plate 2003B may be provided. However, as will be described later, when the formwork 2000 has the inclined plates 2003A and 2003B, By providing the steel pipe with the above-mentioned, the inclination directions of both ends of the steel pipe with respect to the longitudinal direction of the steel pipe are opposite to each other. The flanges FL can be welded together to form a pair.

[0061] The inclined plate 2003 extends over the entire length of the base plate 2001 in the short side direction SS. The height in the vertical direction is greater than the height of the plate-like member 2002. For example, the inclined plate 20 The inclined plate 2003 may have a height that is approximately two to three times the height of the plate-like member 2002. 3, a plurality of (four in this embodiment) holes 2003 are formed through the inclined plate 2003 in the thickness direction. Each of these four holes 2003H is formed in the flange FL. The flange holes are formed in one-to-one correspondence with the four flange holes FLH. It is formed to communicate with the FLH.

[0062] The inclined plate 2003A is provided on the plate-shaped member 2002A in the long side direction LS of the base plate 2001. On the other hand, the plate-shaped member 2002B side is opposite to the plate-shaped member 2002B side (i.e., the plate-shaped member 2002A is used as a reference). In addition, in the long side direction LS of the base plate 2001, the inclined plate 2 003A on the opposite side of the plate-like member 2002A side (i.e., on the side of the inclined plate 2003A as the reference On one side of the base plate 2001, two support plates 2004 are arranged vertically. The following is a list of the inclined plate 2003A that is placed on one side of the inclined plate 2003A. For convenience, the support plate 2004 may be referred to as "support plate 2004A." 004A is a thin plate-like member that can be seen as a trapezoid when viewed from the short side direction SS, and has two supports. The support plates 2004A, 2004A are spaced apart at a predetermined interval in the short side direction SS of the base plate 2001. The surface of the support plate 2004A on the plate-like member 2002A side is spaced apart vertically. The inclined surface 20 inclined to one side in the long side direction LS (the side opposite to the plate-like member 2002A side) The inclination angle α of this inclined surface 2004Aa with respect to the base plate 2001 is The angle α of the flange FL welded to the end of the fourth steel pipe 24 with respect to the longitudinal direction of the fourth steel pipe 24 (see Fig. 3(A)(B)). The inclined plate 2003A is connected to two support plates 2004A and 2004B. By joining to each inclined surface 2004Aa of A, the long side direction is It is erected at an inclination angle α toward one side in the direction LS.

[0063] The inclined plate 2003B is formed on the plate-shaped member 2002B in the long side direction LS of the base plate 2001. On the other hand, on the opposite side to the plate-shaped member 2002A side (that is, on the basis of the plate-shaped member 2002B In addition, in the long side direction LS of the base plate 2001, the inclined plate 2 003B ​​on the opposite side of the plate-like member 2002B side (i.e., on the side of the inclined plate 2003B as the reference On the other side, two support plates 2004, 2004 are vertically extended from the base plate 2001. The inclined plate 2003B is placed on the other side. For convenience, the support plate 2004 is sometimes referred to as "support plate 2004B." The support plates 2004B, 2004B are spaced apart at a predetermined interval in the short side direction SS of the base plate 2001. The surface of the support plate 2004B on the plate-like member 2002B side is spaced apart vertically. The inclined surface 20 inclined toward the other side in the long side direction LS (the side opposite to the plate-like member 2002B side) This inclined surface 2004Ba is also inclined at an angle α with respect to the base plate 2001. The inclined plate 2003B is connected to the inclined surfaces 2003B of the two support plates 2004B. 004Aa, the other side in the long side direction LS with respect to the vertical direction The plate is erected at an angle of inclination α.

[0064] In this way, the formwork 2000 includes a base plate 2001 and a a steel pipe support portion 2010 capable of supporting the steel pipe parallel to the base plate 2001; and a base plate 2001. The inclined plate 2003 is provided at an angle from the steel pipe support portion 201. The inclined plate 2003 is provided to face the end of the steel pipe supported by the A hole 20 communicates with a flange hole FLH (hole) formed in a flange FL welded to the end of the flange FL. 03H is formed

[0065] In the arch material forming step ST20 of this embodiment, the above-described steps are carried out in the formwork preparing step ST21. After preparing such a formwork 2000, a flange placement step ST22 is performed.

[0066] 15 is a front view showing the flange placement step ST22. In the flange placement step ST22, the flanges FL are completely attached to the inclined plate 2003A of the formwork 2000. The four holes 2003H formed in the inclined plate 2003A and the flange FL are brought into surface contact with each other. After communicating with the four flange holes FLH, these four communicating holes 2003H,F By inserting connecting members such as bolts BL into each of the LH, the inclined plate 2003A is The flange FL is held. The entire surface of the flange FL is attached to the inclined plate 2003B of the formwork 2000. The four holes 2003H formed in the inclined plate 2003B and the four holes 2003H of the flange FL are brought into contact with each other. These four communicating holes 2003H, FL By inserting a connecting member such as a bolt BL into each of H, the inclined plate 2003B is attached. That is, by this flange arrangement step ST22, the base plate 2 On one side of the long side direction LS of 001, one flange FL is and is held in a state inclined at an inclination angle α toward one side in the long side direction LS, On the other side in the long side direction LS, another flange FL is The sheet is held in a state inclined at an inclination angle α toward the other side in the side direction LS.

[0067] Next, a steel pipe arrangement step ST23 and a flange welding step ST24 are performed.

[0068] FIG. 16 is a front view showing the steel pipe arrangement step ST23 and the flange welding step ST24. As shown in FIGS. 14 and 16, in the steel pipe arrangement step ST23, the plate-shaped member 2002A A steel pipe (in this embodiment, the fourth Then, the steel pipe (fourth steel pipe 24) is placed in the recesses 2011, 2011. Two protrusions 20 formed on the inner circumferential surfaces 2012, 2012 defining the respective 13, 2013, and is bridged over the plate-like members 2002A and 2002B. That is, in the steel pipe arrangement step ST3, the steel pipe (fourth steel pipe 24) is placed in the steel pipe support portion 201. 0 is supported parallel to the base plate 2001. At this time, in the long side direction LS, The plate 2003A is an end portion of one side of the steel pipe (fourth steel pipe 24) supported by the steel pipe support portion 2010. 24Ea, and the inclined plate 2003B is opposite to the other end of the steel pipe (fourth steel pipe 24). It faces the portion 24Eb.

[0069] By the way, the steel pipe (fourth steel pipe 24) is placed on the protrusions 2013, 2013. Therefore, the plate-like members 2002A and 2002B are supported at a distance from the inner peripheral surfaces 2012 and 2012. This allows the steel pipe to be connected to the plate-like member 2002 even if the cross section of the steel pipe is not a perfect circle. The recess 2011 can be securely supported.

[0070] As shown in FIG. 16, in the long side direction LS of the steel pipe (fourth steel pipe 24), The end 24Ea on one side of the long side LS is The steel pipe (fourth steel pipe 24) is processed so as to be inclined at an inclination angle α. The other end 24Eb in the long side direction LS is on the other side in the vertical direction. Therefore, the steel pipe support portion 201 is processed so as to be inclined at an inclination angle α. When the steel pipe (fourth steel pipe 24) is supported parallel to the base plate 2001 through the The end 24Ea of the tube 24 is inclined to one side at an inclination angle α by an inclined plate 2003A. The end 24Eb is in almost full contact with the flange FL which is attached to the end 24Eb by the inclined plate 2003B. The flange FL is supported at an angle α to the other side and comes into almost full contact with the flange FL.

[0071] In this state, the flange welding step ST24 is performed. As shown, the end 24 of the steel pipe (fourth steel pipe 24) arranged in the steel pipe support portion 2010 of the formwork 2000 Ea and 24Eb are placed on the inclined plates 2003A and 2003B of the formwork 2000, respectively. The ends 24Ea and 24Eb of the steel pipe (fourth steel pipe 24) are welded to the flange FL. b, flange FL is welded diagonally to the longitudinal direction of the steel pipe (fourth steel pipe 24). As a result, the arch material 20 is formed.

[0072] In this way, according to the arch material forming step ST20, by using the formwork 2000, The flange FL is attached to the steel pipe while maintaining a state in which it is inclined at an angle α with respect to the longitudinal direction of the steel pipe. Since the flange FL can be welded, the flange FL is precisely welded at an angle α. 0 can be formed.

[0073] In addition, when forming the upstream arch member 21 (see FIG. 3(A)), the inclined plate 2003A, 2003B in the long side direction LS, the downstream side When forming the arch material 22 (see FIG. 3(B)), the length between the inclined plates 2003A and 2003B is Formwork 2000 in which the interval in the side direction LS is shorter than that in the case of forming the upstream arch member 21 Just use

[0074] As shown in Figure 5, the dam construction method M1 includes a base construction process ST10 and an arch material formation process ST11. After step ST20 is performed, dam construction step ST30 is performed.

[0075] The dam construction step ST30 is a step of constructing a plurality of base portions 1 formed in the base portion construction step ST10. 0 and the plurality of arch members 20 formed by the arch member forming step ST20 are used to form the dam 1. The base 10 and the arch members 20 are then transported to the construction site (river) and used to construct the dam 1. This is the process of construction.

[0076] In the dam construction process ST30, first, for example, one side ( In the left side of the area, there are multiple (two in the example of Figure 1) upstream UF and downstream DF. ) are arranged in a vertical direction. Regarding 10, 10, the flanges FL welded to the first steel pipes 11, 11 are For example, the base portions 10, 10 are connected by bolt joints and are adjacent in the flow direction RF. In this case, the flanges FL welded to the respective second steel pipes 12, 12 are connected to each other by, for example, bolts. At this time, as described above, the plurality of base parts 10 are connected with high precision, that is, Since all the base parts 10 are formed to have the same dimensions and shape, it is possible to precisely assemble a plurality of base parts 10. As shown in the example of FIG. 1, the dam construction process S In T30, the upper and lower regions in the upstream UF and downstream DF in the left region are In the example of FIG. 1, four bases 10 are assembled in the left area. Part 10 is assembled.

[0077] Next, in the area on one side (left side) of the transverse RC, multiple The other end (right side) of the third steel pipe 13 of each of the base portions 10 (4) is welded to the other end (right side). The flange FL of the arch member 20 formed in the arch member forming step ST20 is The flange holes FLH of the third steel pipe 13 and the arch members 2 are in full contact with each other. After connecting the flange holes FLH and FLH of the base, The third steel pipe 13 of the body 10 and the fourth steel pipe 24 of the arch member 20 are connected by bolts or the like. That is, in each of the plurality of base parts 10 constructed in the base part construction step ST10, The arch members 20 are fixed to the respective third steel pipes 13. In the arch member 20, the flange FL is precisely angled at an angle α Therefore, the third steel pipe 13 of the base portion 10 and the fourth steel pipe 20 of the arch member 20 are welded together. 4 by bolting or the like, the first arch member 20 is The fourth steel pipe 24 is inclined at a desired angle with high precision relative to the longitudinal direction of the third steel pipe 13 of the base portion 10. In this state, the pipe is connected to the third steel pipe 13 .

[0078] Next, the third steel pipe 13 of the base portion 10 assembled in the region on one side (left side) is connected to the third steel pipe 13. The flange FL is welded to the other end (right side) of the steel pipe 24. The flange FL welded to one end of the steel pipe 13 is butted against the flange hole The third steel pipe 13 of the base portion 10 and the fourth steel pipe 24 of the arch member 20 are connected to each other via the FLH and FLH. As shown in Figure 1, the RC in the transverse direction is connected by bolt joints, etc. (See Figure 4). The base part 10 is assembled in the area on one side (left side) of the RC, and the center area in the transverse direction In the example of Figure 1, there are two ducts in the upstream UF and downstream DF. The base parts 10 (each, i.e., four parts) are connected to the arch members 20 in the transverse direction RC. The plurality of base parts 10 in the central region are also connected to each other by the base parts 1 in the left region. In the same way as with the 0, flanges FL and FL are butted together and the flange holes FLH and F are connected. It goes without saying that they are connected via the LH using bolt joints or the like.

[0079] Similarly, as shown in FIG. 1, the third steel pipe 13 of the base portion 10 in the central region is The flange FL of the arch member 20 is butted against the flange FL welded to the other side (right side). The arch member 20 is connected to the base portion 10 in the central region, and finally, the other side of this arch member 20 is The flange FL is welded to the other side (right side) of the base portion 10, and the other side of the third steel pipe 13 is welded to the flange FL. The flange FL welded to the end of the base part 10 (left side) is butted against the arch member 2. 0. In this way, the dam 1 shown in FIG. 1 is constructed with high accuracy.

[0080] In the above example, the assembly of the base part 10 on one side (left side) in the transverse direction RC, Connecting the arch member 20 to the left base portion 10, assembling the center base portion 10, and The weir is constructed in the following order: connecting the arch member 20 to the body 10, and assembling the base body 10 on the other side (right side). Although an example of constructing the dam 1 by carrying out the dam construction step ST30 has been described, this order may be changed as appropriate. For example, when assembling the base part 10 on the center side, Connecting the arch material 20, assembling the base part 10 on the left side, and connecting the arch to the right side of the base part 10 on the center side. The dam construction process ST30 is carried out in the order of connecting the base members 20 and assembling the right-side base portion 10. A dam 1 may be constructed.

[0081] In this way, the dam construction method M1 according to this embodiment is a method for constructing a plurality of base portions 10. and a part construction step ST10, in which flanges FL are welded to the ends of the plurality of fourth steel pipes 24. The arch member forming step ST20 for forming the arch member 20 and the base part constructing step ST10 Each of the plurality of third steel pipes 13 in each of the plurality of constructed base portions 10 is provided with an articulated The dam construction process ST30 connects the arch members 20. A flange FL is welded to the end of the fourth steel pipe 24 at an angle to the longitudinal direction of the fourth steel pipe 24. do.

[0082] According to the dam construction method M1, as described above, an arch-shaped dam can be constructed with high precision. It is possible.

[0083] Although the present invention has been described above using the above embodiment as an example, the present invention is not limited to this. isn't it.

[0084] For example, in the dam construction method M1 according to the above embodiment, as shown in FIG. 16, In the forming step ST20, a flange FL is formed on the end portions 24Ea and 24Eb of the fourth steel pipe 24. An example of welding at an angle to the longitudinal direction of the steel pipe 24 has been described. However, as shown in FIG. A dam construction method M2 may be performed. Figure 17 is a flow chart showing the dam construction method M2.

[0085] As shown in FIG. 17, the dam construction method M2 includes a formwork preparation process ST21, a flange placement process ST22, and a ST22, steel pipe placement process ST123, and flange welding process ST24 are all included in the arch material formation process. This is the same as the dam construction method in that it is performed in the base construction step ST110 rather than in step ST120. This differs from Law M1.

[0086] The formwork preparation process, flange placement process, and flange welding process are As the same symbols as those in method M1 are used, the only difference is the timing of performing them. The contents to be implemented are the same, so a detailed explanation of these will be omitted. , and other steps in the dam construction method M2 that are given the same reference numerals as those in the dam construction method M1 , as the content is the same as that of dam construction method M1, a detailed explanation will be omitted.

[0087] As shown in FIG. 17, the dam construction method M2 includes a base construction step ST110 and an arch member construction step ST111. The process includes a construction step ST120 and a dam construction step ST30.

[0088] In the base construction step ST110, first, in the formwork preparation step ST21, the 18 is prepared. Then, in the flange arrangement step ST22, As shown in FIG. 1, a flange FL is provided on one of the inclined plates 2003A and 2003B of the formwork 2000. FIG. 18 shows an example in which a flange FL is arranged on an inclined plate 2003A.

[0089] Next, a steel pipe arrangement step ST123 is performed. Specifically, as shown in FIG. The third steel pipe 13 is inserted into the recess 2011 of the plate-like member 2002A and the recess 2011 of the plate-like member 2002B. In this way, the third steel pipe 13 is placed on the base plate members 2002A and 2002B. In this case, the inclined plate 2003A is supported in parallel with the inclined plate 2001 in the long side direction LS. It faces the end 13Ea of the third steel pipe 13 supported by the steel pipe support portion 2010. The end 13Ea of the 3 steel pipe 13) is directed toward one side in the long side direction LS with respect to the vertical direction. Therefore, the steel pipe support part 2010 is processed so as to be inclined at an angle of approximately α. When the third steel pipe 13 is supported parallel to the base plate 2001, the end 13Ea of the third steel pipe 13 is a flange FL that is inclined to one side at an inclination angle α via an inclined plate 2003A. Almost full contact.

[0090] In this state, the flange welding step ST24 is performed. As shown, the end 13Ea of the third steel pipe 13 arranged in the steel pipe support portion 2010 of the formwork 2000 is The flange FL is welded to the inclined plate 2003A of the formwork 2000. The flange FL is precisely aligned at an angle to the longitudinal direction of the third steel pipe 13 at the end 13Ea of the third steel pipe 13. Well welded.

[0091] Next, as shown in FIG. 17, a marking step ST11, a first steel pipe arrangement step ST12, a second steel pipe arrangement step ST13, and a A steel pipe arrangement step ST13, a first welding step ST14, and a rotation step ST15 are then performed. The third steel pipe arrangement step ST16 is performed. That is, the flange FL is attached to the end portion 13Ea of the third steel pipe 1 The third steel pipe 13 welded diagonally to the longitudinal direction of the first steel pipe 3 is connected to the horizontal band 102 as shown in FIG. 1, 1022. The end of the third steel pipe 13 on the opposite side to the flange FL side is It should be noted that the first steel pipe 11 is pre-processed so as to fit the outer circumferential surface of the first steel pipe 11. In this way, the third end 13Ea is welded at an angle to the flange FL. A plurality of base portions 10 each including a steel pipe 13 are constructed at once with high precision.

[0092] In this way, in the dam construction method M2, the third steel pipe 13 A flange FL is welded to the end 13Ea of the third steel pipe 13 at an angle to the longitudinal direction of the third steel pipe 13.

[0093] In addition, in the dam construction method M2, an arch member forming step ST120 is performed. The forming step ST120 may be performed after the base part constructing step ST110, or after the base part constructing step ST110. This may be performed before ST110 or simultaneously with the base part construction step ST110. Specifically, as shown in FIG. 19, flanges FL are attached to both ends of the fourth steel pipe 24. In this way, flanges FL are welded perpendicularly to the longitudinal direction of the fourth steel pipe 24. Direct welded arches 120 are formed.

[0094] In the dam construction method M2, the dam construction step ST30 is finally performed. The flange FL of the third steel pipe 13 of the base part 10 constructed by the construction step ST110 is The flanges FL of the arch members 120 formed in the arch member forming process ST120 are butted together. The third steel pipe 13 of the base portion 10 is then connected to the arch member 120. As described above, the base part 10 constructed in the base part construction step ST110 is A flange FL is welded to the end 13Ea of the third steel pipe 13 at a desired angle α with high precision. Therefore, the arch member 120 with flanges FL welded vertically to both ends of the fourth steel pipe 24 is By connecting to the flange FL of the third steel pipe 13, an arch-shaped dam can be constructed with precision. It is possible.

[0095] In addition, a person skilled in the art can easily understand the dam construction method of the present invention and the dam construction method according to the conventionally known knowledge. The molds that can be used in the method can be modified as needed. As long as it has the above-mentioned structure, it is of course included in the scope of the present invention. [Explanation of symbols]

[0096] 1...Weir, 10,10A,10B,10C,10D,10E...Base part, 11...First steel pipe ( Steel pipe), 12...Second steel pipe (steel pipe), 13...Third steel pipe (steel pipe), 13Ea...End, 20,1 20...Arch material, 24...Fourth steel pipe, 24Ea, 24Eb...End, 1000...Surface plate, 100 1... scribed line, 2000... formwork (predetermined formwork), 2001... base plate, 2002... plate-shaped portion material, 2003...inclined plate, 2003H...hole, 2010...steel pipe support part, 2011...recess, 20 12...inner surface, 2013...projection, FL...flange, FLH...flange hole (hole), M1, M 2... Dam construction method, ST10, ST110... Base construction process, ST20, ST120... Sandwich material forming process, ST30...dam construction process, X...first direction, Y...second direction, Z...third direction

Claims

1. A dam for constructing a dam that protrudes vertically upstream of a river 1. A method of construction comprising: The dam is Each of them has a first steel pipe extending in a first direction and a second steel pipe extending in a second direction perpendicular to the first direction. a plurality of second steel pipes that are located at positions perpendicular to the first direction and the second direction and that intersect the first steel pipes; and a plurality of third steel pipes extending in a third direction and intersecting the first steel pipe and the second steel pipe. a plurality of base portions; each of which is on a plane defined by the second direction and the third direction, a plurality of third steel pipes connected to each other and extending obliquely with respect to the longitudinal direction of the third steel pipes; Number of fourth steel pipes and Including, The dam construction method includes: a base part construction step of constructing the plurality of base parts; A flange is welded to each end of the plurality of fourth steel pipes to form an arch member. a chip forming process; The multiple layers in each of the plurality of base portions constructed by the base portion construction step a dam construction step of connecting the arch members to each of the third steel pipes; Equipped with In the arch member forming step, a flange is attached to the end of the fourth steel pipe in the longitudinal direction of the fourth steel pipe. or in the base construction step, a flange is welded to the end of the third steel pipe. A dam construction method, wherein the flange is welded obliquely to the longitudinal direction of the third steel pipe.

2. 2. The dam construction method according to claim 1, wherein the base construction step is carried out on a surface plate on which a scribed line is drawn. method.

3. In the arch member forming step, a flange is attached to the end of the fourth steel pipe in the longitudinal direction of the fourth steel pipe. and a step of welding the end of the third steel pipe obliquely to the direction of the base portion in the step of constructing the base portion. Each of the steps of welding the flange obliquely to the longitudinal direction of the third steel pipe is performed using a predetermined formwork. The dam construction method according to claim 1 or 2, which is carried out using a

4. The predetermined formwork is A base plate and a steel pipe support portion attached to the base plate and capable of supporting a steel pipe parallel to the base plate; 、 an inclined plate erected at an angle from the base plate; Equipped with The inclined plate is provided so as to face the end of the steel pipe supported by the steel pipe support portion. And, The inclined plate has holes that communicate with holes formed in a flange welded to the end of the steel pipe. The dam construction method according to claim 3, wherein the dam is formed.

5. The steel pipe support portion includes a plurality of plate-like members arranged at predetermined intervals, Each of the plurality of plate-like members has a semicircular recess having a diameter equal to or larger than the diameter of the steel pipe. The dam construction method according to claim 4, wherein:

6. The steel pipe is spaced from the inner peripheral surface of the plate-like member that defines the recess.

6. The dam construction method according to claim 5, wherein the supporting projections are protruding.

7. The steel pipes that make up the dam are projected vertically upstream of the river. A form for welding a flange, A base plate and a steel pipe support portion attached to the base plate and capable of supporting a steel pipe parallel to the base plate; an inclined plate erected at an angle from the base plate; Equipped with The inclined plate is provided so as to face the end of the steel pipe supported by the steel pipe support portion. And, The inclined plate has holes that communicate with holes formed in a flange welded to the end of the steel pipe. Forming, formwork.

8. The steel pipe support portion includes a plurality of plate-like members arranged at predetermined intervals, Each of the plurality of plate-like members has a semicircular recess having a diameter equal to or larger than the diameter of the steel pipe. The formwork according to claim 7, wherein:

9. The steel pipe is spaced from the inner peripheral surface of the plate-like member that defines the recess.

9. The formwork of claim 8, wherein a plurality of supporting projections protrude.

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