JP2010084455A - Cross beam buttress type open dam - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a cross beam buttress type open dam with an excellent function of catching the slurry of mud and rock which is improved in impact resistance and abrasion resistance and whose structure is simple and easy to be constructed and repaired. <P>SOLUTION: The cross beam buttress type open dam includes : a structure body 4 with a plurality of buttresses 7 arranged at intervals in the direction of crossing a river and a crown strut 8 mounted to a top of the plurality of the buttresses 7; a plurality of joint spacer supports 32 connected with an upstream side of a plurality of the buttresses 7; a plurality of lateral beams 30 supported by a plurality of the joint spacer supports 32 and placed horizontally at vertical intervals; and a plurality of vertical beams 31 placed at intervals in a direction crossing the river between the plurality of joint spacer supports 32 and the plurality of lateral beams 30. The dam also includes a screen function body 5 arranged at the upstream side of the structure body 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a transmission-type sabo dam (transmission-type sabo dam), and in particular, as a screen function unit for capturing a debris flow, a detachable horizontal beam is mainly used as a longitudinal beam (in the form of crossing it in front of it). Steel beam is a closed-type cross beam buttress type open embankment that combines a concrete wall covered with a steel shell made of straight steel sheet piles as a structural part that supports it behind. Dam). In the present specification, the term “enbankment (dam)” is used, but “enbankment” is generally used by those skilled in the art as synonymous with “dam”.

  Conventionally, there are a comb-type concrete slit embankment and a transmission-type sabo dam in the debris flow section.

  A comb-shaped concrete slit embankment is a conventional impervious concrete sabo dam with a large number of slits formed into a comb shape, and a large number of walls between the slits are made of reinforced concrete.

  The permeable sabo levee is installed for the purpose of capturing debris flow and reducing the peak flow of debris flow, especially in a debris flow section where a debris flow is generated. On the other hand, it is expected that the sand storage capacity will be maintained, and if drifting of a driftwood is expected, an effect as a driftwood stop can be expected.

  Also, even in the headwater section, sediment should flow down as much as possible in rivers where there is little sediment flow when there is constant water discharge and the downstream river bed is drastically lowered. Is expected.

  One type of permeable sabo dam is a permeable steel sabo dam. This is a frame structure in which steel pipes are joined by a flange joint, and is called a so-called lattice steel sabo dam, steel slit B type, or the like.

  The present applicant, as a dam that belongs to the technical field of transmission-type sabo dams, already has a plurality of buttresses and their top ends arranged so as to form openings at appropriate intervals in the transverse direction of the river. The buttress and the top slab are hybrid buttress type with a hybrid buttress structure that is a strong steel-concrete structure with the inside and outside of the concrete sufficiently reinforced with H-section steel and other steel materials. An open dam is proposed (see Patent Document 1).

Japanese Patent No. 3536030

Each of the conventional techniques has the following problems.
(1) The conventional comb-shaped concrete slit dam has the following problems. The cross section is reduced due to the wear of the concrete on the side surface of the slit. The cold joint generated at the horizontal joint of concrete causes a reduction in impact resistance. Construction costs increase due to the complexity of design and construction due to the use of reinforcement and formwork.

(2) Conventional transmission steel sabo dams require a complicated design to allow local buckling of the steel pipe and plastic deformation of the entire structure, and are expensive due to the use of a steel pipe flange joint. .

  The hybrid buttress-type open dam described in Patent Document 1 has a configuration that eliminates the problems of the conventional comb-shaped concrete slit dam and transmission steel sabo dam and has high impact resistance and wear resistance. The present invention further realizes a buttress-type open dam that has an excellent debris flow capturing function, improves impact resistance and wear resistance, and is simple in structure and easy to design and repair. It is to be an issue.

  In order to solve the above-mentioned problem, the present invention provides a structural body portion having a plurality of anchor walls arranged at intervals in the transverse direction of the river and a ceiling strut erected on the ceiling ends of the plurality of anchor walls. And a plurality of joint spacer columns provided so as to be coupled to the upstream side of the plurality of ribs, a plurality of transverse beams supported by the plurality of joint spacer columns and arranged horizontally at intervals in the vertical direction, And a screen function disposed between the plurality of joint spacer columns and the plurality of transverse beams at an upstream side of the structure body having a plurality of longitudinal beams arranged at intervals in the transverse direction of the river A cross-beam buttress-type open embankment comprising: a steel shell body including left and right side steel shell walls, an upstream steel shell wall, and a downstream steel shell wall toward the upstream side; The interior of the steel shell The upstream steel shell wall has a flange, and the joint spacer column is formed by stacking a plurality of steel joint spacers in the vertical direction, Each of the plurality of joint spacers has a flange portion, and is constructed by fitting the flange portion to the flange portion of the upstream steel shell wall from above to couple to the upstream steel shell wall and being stacked vertically. A cross-beam buttress-type open embankment characterized in that it is configured.

  The flange portion of the upstream steel shell wall is formed at the left and right corners of the upstream steel shell wall having a U-shaped cross section, and the joint spacer includes a cylindrical portion extending in the vertical direction, and the cylindrical portion Left and right sheet pile portions extending toward the upstream side from the respective left and right sheet pile portions, and the flange portions of the joint spacers are formed at the downstream ends of the left and right sheet pile portions, respectively. It is preferable that the flange formed at the corner and the flange of the joint spacer are fitted to form a joint joint.

  The plurality of vertical beams may be supported by a horizontal beam supported horizontally on the upstream side of the horizontal beam on a notch formed in a joint spacer cylindrical portion of a joint spacer column. preferable.

  The left and right side steel shell walls of the saddle wall are fixed to left and right flank members disposed horizontally at intervals in the vertical direction on the inner surface, and the left and right flank members are joined to each other by tie materials. It is preferable to have a configuration.

According to the configuration of the cross beam buttress type open dam according to the present invention as described above, the following effects are produced.
(1) The entire upstream surface is covered by the screen function portion so that the structure portion is not directly hit by the debris flow, and the impact force can be greatly reduced. In short, a screen function part is provided in front of the structure part consisting of dredging walls (buttresses), and impact energy of debris flow, gravel, driftwood, etc. is received by the screen function part to absorb impact energy and prevent direct hit on the dredging wall. The impact force can be greatly reduced.

(2) By using a fitting joint of a linear steel sheet pile to join the structural part member and the screen functional part member, the structural part member and the screen functional part member can be separated and integrated. Thus, it is possible to easily attach and detach and replace the members of the screen function unit. This produces the following effects.
A. When debris removal after debris flow capture is difficult to approach from the upstream side, the member of the screen function part is removed to allow access from the downstream through the buttress span, and maintenance can be easily performed.
I. The screen function unit easily replaces and adjusts the screen function part when it exceeds the limit strength where gravel collision is captured multiple times or when it is desired to change the slit interval in the future. can do.

  (3) Since the high-strength bolts and welding are not used at all for connecting the structure part and the screen function part to each other, the straight steel sheet piles are connected to each other by the fitting joint, so the design and construction Is simplified, and the attachment and detachment and replacement of the members of the screen function unit are simplified, and repair and the like are facilitated. Further, as a derivative effect, it is not necessary to process members such as a horizontal beam and a vertical beam of the screen function unit.

  (4) The debris flow capture function can be complemented by superimposing a plurality of vertical beams on the front of a plurality of horizontal beams, and by supporting the vertical beam with a horizontal beam supported by a joint spacer, A fixing structure in the beam grating contact portion (crossing portion) is unnecessary, and processing of each beam for fixing can be made unnecessary.

  (5) The ridge wall that constitutes the structure part is made of a synthetic steel structure combined with concrete, and has a structure that minimizes joining means such as high-strength bolts and welding (for some fixing structures such as fixing the top slats) Use), it is possible to simplify and rationalize design construction and repair. Thereby, construction cost, repair cost, etc. can be reduced.

Furthermore, the cross beam buttress type open dam according to the present invention has the following remarkable effects as a transmission type sabo dam.
(6) The opening degree of the water passage part is not inferior to that of conventional transmission steel sabo dams, so that it provides a reliable debris flow trapping effect and a debris flow peak flow reduction effect, as well as a reduced sediment flow capacity during medium and small floods. It is possible to prepare to capture the next debris flow by ensuring the sand storage capacity without causing sedimentation.

  (7) The dredging wall has a steel / concrete hybrid structure in which concrete is covered with steel bulkheads. Therefore, conventional transmission steel sabo dams and comb-shaped concrete slits against the impact force of debris flow, gravel, driftwood, etc. Compared to a dam, it not only has a very high shear strength, but even if its surface is brought into contact with a debris flow or a debris flow, the wear of the wall surface panel can suppress wear on the side surface of the dredged wall.

  The best mode for carrying out the cross beam buttress type open embankment according to the present invention will be described in detail with reference to the drawings based on the embodiments.

  FIG. 1 is a perspective view showing a general configuration of a cross beam buttress type open embankment according to the present invention. FIGS. 2 (a), 2 (b), and 3 to 8 are cross beam buttress type open embankments according to the present invention. It is a figure explaining the structure of the Example of an embankment, and FIG.2 (c) is a figure which shows a structure without a dredging wall in the concrete side wall of the both sides of a river. Examples will be described with reference to FIGS. In the present specification, the term “left and right” is used to mean left and right toward the upstream side.

(overall structure)
As shown in FIGS. 1 and 2, a cross beam buttress-type open embankment 1 according to the present invention is between concrete side walls 2 constructed on both banks of a river, 4 and a screen function body portion 5 are arranged in a composite structure. A feature of the cross beam buttress type open embankment 1 according to the present invention is that the structure body portion 4 and the screen function body portion 5 are configured to play distinctly different roles.

  That is, the cross beam buttress type open embankment 1 of the present invention is arranged by the screen function body portion 5 by the debris flow, gravel, driftwood, etc. by arranging the screen function body portion 5 on the upstream surface (front surface) of the structure body portion 4. In response to the impact, direct impact on the structure is prevented, and the impact force is greatly reduced. On the other hand, the structure 4 is configured to support the screen function body 5 from the downstream surface (back surface). A type of open dam.

(Structure part)
As shown in FIGS. 1 and 2 (a) and 2 (b), the structure portion 4 includes a plurality of wall walls (buttresses) arranged so as to form openings 6 at appropriate intervals in the river transverse direction. ) 7, and the top end struts 8 are installed on the top end portions of the plurality of eaves walls 7 to construct the whole. Among the plurality of dredging walls 7, the dredging walls 7 on both sides in the river crossing direction are respectively installed in contact with the concrete side walls 2 on both banks of the river.

  And between the dredging wall 7 of both sides, according to the river width, the dredging wall 7 is not provided, or 1 or more is installed. Through the openings 6 between the plurality of eaves walls 7 installed in this way, the running water and earth and sand from the medium and small water flows down. In this embodiment, as shown in FIGS. 2 (a) and 2 (b), the left and right side walls in the river transverse direction (the side wall 7 is on the downstream side of the joint column spacers 32 on the left and right sides. a) and (b) are not visible) and between the left and right side walls, there is one wall (this wall 7 is downstream of the central joint column spacer 32, and FIG. A) and (b) are not visible. The explanation will be focused on the cross-beam buttress-type open embankment 1 installed.

  2 (b) is a view of the cross beam buttress-type open embankment 1 of FIG. 2 (a) as viewed from the upstream side. The configuration shown in FIG. The wall 7 is downstream of the joint column spacers 32 on the left and right sides and is not visible in FIG. 2 (c). It is the figure which looked at from the upstream.

  As shown in FIGS. 3 and 6 (a), the wall 7 has a substantially right-angled triangle as viewed from the side. FIG. 5 (a) shows a plan view of the eaves wall 7, and FIG. 6 (b) shows a cross-sectional view of the eaves wall 7. The eaves wall 7 has left and right side steel shell walls 10, upstream steel toward the upstream side. The shell wall 12 and the downstream steel shell wall 13 are combined with each other to provide a substantially triangular steel shell body 14 having a space formed therein.

  As shown in FIGS. 3 and 6 (a), the left and right side steel shell walls 10 are formed as wall surfaces by combining a plurality of linear steel sheet piles 15 in a zigzag shape in the upstream and downstream directions and in the vertical direction. Yes. As shown in FIG. 6 (c), the linear steel sheet pile 15 used here is formed with ridges 16 along both side edges (edges in the river flow direction), and adjacent linear shapes. By fitting the flanges 16 of the steel sheet piles 15, the wall surfaces can be formed in a zigzag manner as described above.

  The left and right linear steel sheet piles 15 forming the left and right side steel shell walls 10 are horizontally provided on the inner surface at intervals in the vertical direction, as shown in FIGS. 3 and 6B. Bolts are fastened to a plurality of bellows members (“angle steel” is used) 17 and fastened to each other. The left and right belly raising members 17 to which the left and right side steel shell walls 10 and 11 are fixed are connected to each other by a tie material 18.

  As shown in FIGS. 3 and 6 (a), the upstream steel shell wall 12 has an upstream steel shell material 19 erected in the foundation concrete 2 via anchor bars (reinforcing bars) 25, and a plurality of upstream steel shell walls A steel shell material 19 is formed by joining. As shown in the cross-sectional view of FIG. 6 (d), the upstream steel shell 19 is formed by welding left and right straight steel sheet piles 19a and a central straight steel sheet pile 19b into a U-shaped cross section. Yes.

  In the upstream steel shell material 19 (upstream steel shell wall 12), a flange portion 20 and a flange portion 21 are formed at both left and right end portions and corner portions, respectively. The flanges 20 at the left and right ends of the upstream steel shell 19 are fitted and locked with the flanges 11 at the upstream ends of the left and right side shell walls 10. As will be described later, the flange portions 21 at the left and right corners of the upstream steel shell material 19 become a part of the fitting joint 22 that couples the screen function body portion 5 and the flange wall 7.

  Similarly to the upstream steel shell wall 12, the downstream steel shell wall 13 is formed by joining a plurality of downstream steel shell members 23 having a U-shaped cross section made of straight steel sheet piles in the vertical direction. The downstream steel shell member 23 (downstream steel shell wall 13) has flanges 24 formed at both left and right ends thereof. The flange portions 24 at both the left and right end portions are fitted and locked to the flange portions 11 at the downstream ends of the left and right side steel shell walls 10.

  The left and right side steel shell walls 10, the upstream steel shell wall 12 and the downstream steel shell wall 13 each have a bottom concrete portion together with anchor bars (rebars) 25 arranged vertically inside the steel shell body 14. 3 is embedded and fixed upright. In the inner space of the steel shell body 14 surrounded by the left and right side steel shell walls 10, the upstream steel shell wall 12 and the downstream steel shell wall 13, a joint rebar 29 is installed and an internal concrete 26 is placed. Has been.

  As shown in FIG. 1 and FIG. 2 (a), the top end struts 8 are respectively provided at the top ends of the plurality of side walls 7 so as to bridge the plurality of side walls 7 spaced in the river crossing direction. Is built. As this top end strut 8, as shown in FIG. 5 (b), two rows of small rectangular cross-section steel pipes 27 and one row of rectangular cross-section steel pipes 28 extend so as to extend in the river transverse direction. At the top end, it is fixed to the upper surface of the internal concrete 26 by a top end shear bar, a section steel and a bolt.

  As described above, the rib wall 7 of the present invention is formed by combining the straight steel sheet piles 15 and fixing from the inner side with the bellows material 17 and the tie material 18 to form the left and right steel shell walls 10. 10 and a steel shell body 14 formed by fitting the upstream steel shell wall 12 and the downstream steel shell wall 13 with each other at the flange portion, and an internal concrete reinforced with anchor bars 25 is placed. is there.

  In short, since the wall 7 is a hybrid structure formed of steel and concrete, it has not only extremely high strength against impact forces such as debris flow, gravel, driftwood, etc., but also its surface in debris flow and debris flow. Even if they come into contact with each other, the wear resistance of the wall panel can suppress the wear of the surface, and furthermore, no joint means such as high-strength bolts or welding is required, so that the design and construction can be simplified and simplified. .

  And the eaves wall 7 is a hybrid structure that takes advantage of the characteristics of both steel material that is strong in tension and concrete that is strong in compression and can be expected to have a gravitational effect, and a linear steel sheet pile 15 is used as the main steel material. Therefore, the flange portion 21 of the upstream steel shell wall 12 of the flange wall 7 forms a fitting joint 22 with the flange portion 45 of the screen functional body portion 5, and the flange wall 7 and the screen functional body portion 5 are simply connected. Can be integrated. In addition, the steel shell 14 of the wall 7 is configured to exhibit a formwork function for placing the internal concrete 26.

(Screen function body)
Next, the screen function body unit 5 will be described. As shown in FIGS. 1, 2 (a), 2 (b) and FIG. 4, the screen function body 5 includes a plurality of horizontal beams 30, a plurality of vertical beams 31, a plurality of joint spacer columns 32, An intermediate horizontal beam 33 that supports the beam 31 in the middle in the vertical direction and a top horizontal beam 34 that supports the vertical beam 31 at the top are provided.

  In this embodiment, one intermediate horizontal beam 33 is provided in the vertical direction. Originally, the number of the vertical horizontal beams 33 is determined in accordance with the height of the cross beam buttress type open dam 1. If the height is low, it may not be provided. Moreover, when the height of the cross beam buttress-type open embankment 1 is relatively high, the number of the intermediate horizontal beams 33 in the vertical direction may be two or more.

  The plurality of joint spacer columns 32 are arranged on the front surface of the plurality of ridge walls 7 at intervals in the river crossing direction (see FIG. 3).

  In this embodiment, one joint spacer column 32 is installed between the joint spacer columns 32 on both sides (see FIG. 2B). The joint spacer column 32 is provided corresponding to the dredging wall 7. Depending on the river width, as shown in FIG. 2C, there is a configuration in which the joint spacer column 32 is not provided. However, there is a configuration in which two or more are installed.

  As shown in FIGS. 1, 3 and 4, the joint spacer column 32 has a plurality of steel joint spacers (“standard joint spacer 35” and “horizontal beam spacer” described later) on the front side of the wall 7. Joint spacers 36 ") are built up and stacked in the vertical direction. The joint spacer includes a standard joint spacer 35 that supports only the transverse beam 30 as shown in FIG. 7, and a joint spacer 36 for the horizontal beam that supports the transverse beam 30 and the horizontal beam 33 or 34 as shown in FIG. There is.

  As shown in FIGS. 7A to 7D, the standard joint spacer 35 is formed of a steel plate material, has an L shape in a side view, and has a kamaboko type (substantially U-shaped) horizontal section. The cylindrical part 37, the right and left linear steel sheet pile part 38 extended from the substantially lower half part of this cylindrical part 37 to the downstream (back side), the back wall part 39 of the cylindrical part 37, and the left and right linear steel sheet pile parts The upper wall part 40 and the bottom wall part 41 which close the upper and lower sides of 38 are provided, and are integrally formed.

  As shown in FIG. 3 and FIG. 7A, the plurality of transverse beams 30 are located in the recesses formed between the plurality of standard joint spacers 35 stacked in the vertical direction and the front surface of the wall 7. These are placed on the left and right linear steel sheet pile portions 38 and the upper wall portion 40, and are supported horizontally at a certain interval in the vertical direction.

  The joint spacers 36 for horizontal beams at the middle and the top end have substantially the same configuration as the standard joint spacer 35, but here, a description will be given focusing on a configuration different from the standard joint spacer 35.

  The horizontal beam joint spacer 36 is a standard joint spacer 35 in which a part on the downstream side (back side) of the cylindrical portion 37 is cut away as shown in FIG. It is the structure which was formed and became the step part by side view. The opening formed in the downstream side and the upper surface by cutting the cylindrical portion 37 is closed by a crank-shaped steel plate material 43 in a side view.

  The horizontal beam joint spacer 36 is placed on the standard joint spacer 35, and the horizontal beam 30 is placed between the horizontal beam joint spacer 36 and the front surface of the eaves wall 7 in the same manner as the standard joint spacer 35. The horizontal beam joint spacer 36 is mounted on and supported by the left and right straight steel sheet pile portions 38 and the upper wall portion 40. And the horizontal beam 33 (or 34) is mounted on the horizontal beam support part 42 in the front surface of the horizontal beam 30 (refer FIG.5 (b), FIG.8 (b)).

  By the way, the cylindrical portion 37 of the standard joint spacer 35 and the horizontal beam joint spacer 36 is formed as a convex curved surface wall 44 on the front surface. Each of the left and right linear steel sheet pile portions 38 has a flange 45 formed at the downstream end (back end). The flange portions 45 of the left and right linear steel sheet pile portions 38 are fitted to the flange portions 21 formed at the left and right corners toward the upstream side of the upstream steel shell wall 12 to form the joint joint 22, thereby The joint spacers 35 and 36 are coupled to the upstream steel shell wall 12 of the wall 7.

  In the intermediate horizontal beam 33, a plurality of circular holes penetrating in the vertical direction are formed at appropriate intervals in the river transverse direction. The plurality of vertical beams 31 are installed through a plurality of circular holes formed in the intermediate horizontal beam 33. The top end horizontal beam 34 is formed with a plurality of circular holes opened downward at appropriate intervals in the river transverse direction. The top horizontal beam is mounted from above so that the upper ends of the plurality of vertical beams 31 are fitted into the plurality of circular holes.

(Example of construction)
A construction example for constructing the cross beam buttress type open embankment 1 according to the present invention will be described in order.

  (1) After constructing the concrete side wall 2 and the foundation concrete 3 on both banks of the river, the dredging wall 7 is constructed on the foundation concrete 3. When constructing the eaves wall 7, the left and right side steel shell walls 10, the upstream steel shell wall 12, the straight steel sheet pile 15 constituting the downstream steel shell wall 13, the upstream steel shell material 19, and the lower end of the downstream steel shell material 23 Are embedded in the foundation concrete 3 together with the anchor bars 25, the jointed reinforcing bars 29 and the like disposed in the space in the steel shell 14 and fixed upright (see FIGS. 3 and 4).

  (2) The left and right side steel shell walls 10 are combined with a plurality of linear steel sheet piles in a staggered manner, and the left and right flank members 17 joined by the tie members 18 are in contact with each other and fixed while facing upward and downward. The side steel shell wall 10 is assembled. While assembling, the left and right side steel shell walls 10, the upstream steel shell wall material 12 and the downstream steel shell wall material 13 are fitted to each other with the flange portion 11 and the flange portions 20 and 24 being fitted to each other. Thus, the steel shell body 14 is constructed (see FIGS. 3 and 6A).

  Thus, in the process of constructing the left and right side steel shell walls 10, the upstream steel shell wall 12 and the downstream steel shell wall 13 upward, the steel shell walls 10, Concrete is poured into the space surrounded by 12 and 13 and placed. In this way, the upside assembly of the steel shell walls 10, 12, 13 and the placement of the internal concrete 26 are repeated to construct the eaves wall 7 formed by placing the steel shell body 14 and the internal concrete 26.

  (3) As shown in FIGS. 1, 2 (a), 3, and 5, the top end struts 8 are formed on the top end portions of the plurality of eaves walls 7 made of the steel shell 14 in which the inner concrete 26 is placed. 2 rows of steel pipes 27 and 1 row of steel pipes 28 are placed so as to extend in the river crossing direction, and as shown in FIGS. It fixes to the upper surface with a top end shear bar, a section steel, and a bolt, and is constructed so as to bridge a plurality of ridge walls 7 spaced in the river transverse direction.

  (4) After the eaves wall 7 is constructed, the eaves 45 of the left and right linear sheet piles 38 of the standard joint spacer 35 are fitted into the eaves 21 at the left and right corners at the upper end of the upstream steel shell wall 12, respectively. The lowermost standard joint spacer 35 is placed on the foundation concrete 3, and the joint spacer above the lowermost standard joint spacer 35 is It is placed on a lower standard joint spacer 35.

  (5) With respect to the standard joint spacer 35, the straight steel sheet pile portion 38 and the upper wall portion 40 on the upstream side of the upstream steel shell wall 12 and downstream of the cylindrical portion 37 of the standard joint spacer 35. The horizontal beam 30 is placed on the top (see FIG. 7A). Further, with respect to the joint spacer 36 for the horizontal beam, the horizontal beam 30 is mounted on the linear steel sheet pile portion 38 and the upper wall portion 40 on the upstream side of the upstream steel shell wall 12 and on the downstream side of the cylindrical portion 37. The intermediate horizontal beam 33 is placed on the cutout of the cylindrical portion 37 (see FIG. 5B and FIG. 8B).

  (6) In this way, after placing the transverse beam 30 or the transverse beam 30 and the intermediate horizontal beam 33 on the joint spacer 35 or 36, the straight steel sheet pile of the upper joint spacer 35 is similarly constructed. The flange portion 45 of the portion 38 is fitted to the flange portions 21 at the left and right corners from the upper end of the upstream steel shell wall 12 and lowered downward, and the upper standard joint spacers 35 are stacked one after another.

  (7) By repeating such stacking of the joint spacers 35 or 36 and placing the transverse beam 30 or the transverse beam 30 and the intermediate horizontal beam 33 thereon, a plurality of joint spacers 35 or 36 are placed on the front side of the eaves wall 7. The joint spacers 35 and 36 are stacked in the vertical direction to construct the joint spacer column 32, and the plurality of horizontal beams 30 and the intermediate horizontal beam 33 are horizontally supported at regular intervals in the vertical direction.

  (8) Although the joint spacer column 32 may have a hollow inside the cylindrical portion 37, it is preferable that the cylindrical portion 37 is filled with sand from above in order to improve the absorbed energy of the joint spacer column 32. (See “packing in sand” in FIG. 9A).

  (9) The horizontal beam 30 and the top horizontal beam 34 are placed on the joint spacer 36 for the top horizontal beam at the uppermost end of the joint spacer column 32, and are fixedly supported by high strength bolts. (See FIG. 5B).

  (10) The plurality of vertical beams 31 are installed through the intermediate horizontal beam 33 through a plurality of circular holes (a plurality of circular holes penetrating in the vertical direction at appropriate intervals in the river transverse direction). The top end of the plurality of vertical beams 31 is fitted with circular holes (a plurality of circular holes formed at appropriate intervals in the river crossing direction) opened below the top horizontal beam 34. Install.

  As described above, the screen functional body portion 5 has the flange portions 45 of the joint spacers 35 and 36 fitted into the flange portions 21 of the corner portions of the upstream steel partition member 19 of the flange wall 7, and a standard joint thereon. The mounting of the spacer 35 is repeated, the joint spacer 36 is fitted in the middle thereof, the intermediate horizontal beam 33 is mounted thereon, and then a plurality of vertical beams 31 are inserted into the holes of the intermediate horizontal beam 33 and installed. The top end horizontal beam 34 is placed at the upper end. Thereby, the screen function body 5 can be constructed so as to be coupled to the front surface of the structure 2.

  As described above, the screen functional unit 5 is simply placed on the foundation concrete 3 and is assembled without being embedded or fixed with bolts, so that the construction is very simple. Members such as the horizontal beam 30, the vertical beam 31, the joint spacers 35 and 36, and the horizontal beams 33 and 34 constituting the screen function body 5 can be easily replaced or replaced when damaged.

(Function)
The operation of the cross beam buttress type open embankment 1 according to the present invention will be described. In the river where the cross beam buttress type open dam 1 is constructed, the debris flow can be captured by the plurality of dredging walls 7, the peak flow rate of the debris flow can be controlled, and driftwood and the like can also be captured. The earth and sand at the time of medium and small water discharge flows through the opening 6 between the walls 7.

  The debris flow, gravel, driftwood, etc. that have flowed from the upstream collide with the joint spacers 35, 36 of the screen function body 5 as shown in FIG. 9A (showing the state where the gravel collides). A dent deformation 46 is generated in the convex curved surface wall 44 or the like. In this way, debris flow, gravel, driftwood, etc. collide with the screen function body 5, so that debris flow, gravel, driftwood, etc. are directly hit against the anchor wall 7 of the structure body 4. Furthermore, the impact force is absorbed by colliding with the lattice portion composed of the transverse beam 30 and the longitudinal beam 31.

  FIG. 9B shows a crossing portion of the horizontal beam 30 and the vertical beam 31 which are a part of the screen function body portion 5, and is a schematic diagram for explaining dispersion absorption of impact force such as debris flow, gravel and driftwood. is there. The impact force P of debris flow, gravel, driftwood, etc. that has collided with the vertical beam 31 is distributed and applied at P / 2 to the crossing portion (supporting portion) with the upper and lower horizontal beams 30. Then, the upper and lower lateral beams 30 receive a reaction force P / 4 from the upstream steel partition wall of the structure in contact therewith.

  In such a case, as shown in FIG. 9 (b), a dent deformation 47 occurs at the point of application of the impact force P of the longitudinal beam 31, and the longitudinal beam 31 subjected to the force of P / 2 is supported. Indentation deformation 48 also occurs in the portion of the transverse beam 30 and the portion of the transverse beam 30 that receives the P / 4 reaction force. In this way, the dent deformation occurs in the support portion other than the operating point, and the impact energy is synergistically absorbed by the cooperation of the dent deformation of the longitudinal beam 31 and the transverse beam 30, and therefore the impact energy absorption performance is extremely large.

  As a result, the wall 7 of the structure 4 plays a role of supporting the screen function body 5 from the downstream side (behind), but the impact force received by the direct hit of debris flow, gravel, driftwood, etc. is greatly reduced. Can be done. For this reason, it is possible to reduce damage to the wall 7 of the structure body 4 that is difficult to repair.

  The structural body portion 4 and the screen functional body portion 5 are joined to each other without using any high-strength bolts or welding, and the flange portion 21 of the upstream steel shell wall 12 of the flange wall 7 and the joint spacers 35, 36. Since the fitting joint 22 is constructed by fitting the flange portions 45 of the straight steel sheet pile portions 38, the design work is simplified and the screen functional body portion 5 is formed by crossing the horizontal beam 30 and the vertical beam 31. Since the fixing structure in the part (lattice contact part) is unnecessary, it is easy to attach and detach and replace, and even if it receives dents or the like by direct hits such as debris flow, gravel, driftwood, etc., the repair is easy.

  Since the impact energy is synergistically absorbed by the cooperation of the dent deformation of the vertical beam 31 and the horizontal beam 30 as described above, the steel pipe size (diameter, thickness, etc.) used for the vertical beam 31 and the horizontal beam 30 respectively. Can be reduced, and the cost can be reduced.

  As mentioned above, although the embodiment of the cross beam buttress type open embankment according to the present invention has been described based on examples, the present invention is not particularly limited to such examples, and the technology described in the claims It goes without saying that there are various embodiments within the scope of the subject matter.

  As described above, the cross beam buttress type open embankment according to the present invention has high strength against impact force and is relatively easy to perform construction, repair, etc., so in small and medium-sized rivers, particularly in mountainous areas. Application as a transmission type sabo dam is suitable.

It is a perspective view which shows the general structure of the cross beam buttress type open embankment which concerns on this invention. (A) is a perspective view of the Example of the cross beam buttress type open embankment concerning this invention, (b) is the front view seen from the upstream, (c) is a figure which shows another embodiment. is there. It is AA sectional drawing of FIG.2 (b). It is the front view seen from the upstream of the said Example. (A) is a top view of the said Example, (b) is a principal part enlarged view of FIG. (A) is a perspective view explaining the structure of the eaves wall of the said Example, (b) is a figure which shows the horizontal cross section of (a), (c) In the top view and front view of a steel shell wall material (D) is a sectional view of the upstream steel shell wall. It is a figure explaining the standard joint spacer of the said Example, (a) is a perspective view, (b) is AA sectional drawing of (c), (c) is a side view, ( d) is a plan view showing a fitting joint between a standard joint spacer and an upstream steel shell wall. It is a figure explaining the joint spacer for horizontal support beams of the said Example, (a) is a side view, (b) is a side view of the state which mounted the horizontal beam and the top end / intermediate horizontal beam. (C) is a front view of the state which mounted the top end and the intermediate | middle horizontal beam. It is a figure explaining the effect | action of this invention, (a) shows the state which the gravel collided with the joint spacer, (b) is a figure which shows the dispersion | distribution state of collision edge energy.

Explanation of symbols

1, 9 Cross beam buttress type open embankment
2 Concrete side walls
3 foundation concrete
4 Structure part
5 Screen function body
6 opening
7 wall
8 Top end struts
10 Left and right side steel shell walls
11 Ridges at upstream ends of left and right side shell walls
12 Upper shell wall
13 Downstream steel shell wall
14 Steel shell
15 Straight steel sheet pile
16 Ridge of straight steel sheet pile
17 Left and right belly
18 Thai wood
19 Upstream steel shell
19a Left and right straight steel sheet piles
19b Central straight steel sheet pile
20 Ridges on both ends of upstream steel shell
21 Ridges on left and right corners of upstream steel shell
22 Fitting joint that joins the screen function body and the wall
23 Downstream steel shell
24 Ridge of downstream steel shell
25 Anchor muscle
26 Internal concrete
27 Steel pipes with small rectangular sections in two rows of top struts
28 Steel pipe with rectangular cross section of top end strut 29 Jointed rebar
30 Horizontal beam
31 Longitudinal beam
32 Joint spacer support
33 Intermediate horizontal beam
34 Top end horizontal beam
35 Standard joint spacer
36 Joint spacer for horizontal beams
37 Tube part of joint spacer
38 Straight steel sheet piles on the left and right of the joint spacer
39 Back wall of joint spacer
40 Upper wall of joint spacer
41 Bottom wall of joint spacer
42 Horizontal beam support of joint spacer
43 Crank-shaped steel plate of joint spacer
44 Convex curved wall of joint spacer
45 Ridge of straight steel sheet pile part of joint spacer
46, 47, 48 dent deformation

Claims (4)

A structure part having a plurality of dredging walls arranged at intervals in the transverse direction of the river and a crest strut laid on the crests of the plurality of dredging walls;
A plurality of joint spacer columns provided so as to be coupled to the upstream side of the plurality of ribs, a plurality of transverse beams supported by the plurality of joint spacer columns and horizontally disposed at intervals in the vertical direction; and A screen function unit having a plurality of vertical beams arranged at intervals in the transverse direction of the river between the plurality of joint spacer columns and the plurality of horizontal beams, and disposed on the upstream side of the structure unit; A cross beam buttress-type open embankment,
The wall has left and right side steel shell walls toward the upstream side, a steel shell body composed of an upstream steel shell wall and a downstream steel shell wall, and internal concrete placed in the steel shell body. The upstream steel shell wall has a flange,
The joint spacer column is formed by stacking a plurality of steel joint spacers in the vertical direction, and each of the plurality of joint spacers has a flange portion, and the flange portion is connected to the upstream steel shell wall. A cross-beam buttress-type open embankment characterized in that it is constructed to be fitted to the flange portion of the steel plate from above and coupled to the upstream steel shell wall and stacked in the vertical direction. The flange portion of the upstream steel shell wall is formed at the left and right corners of the upstream steel shell wall having a U-shaped cross section,
The joint spacer includes a cylindrical portion extending in the vertical direction, and left and right sheet pile portions respectively extending toward the upstream side from the cylindrical portion, and the joint spacer is disposed at a downstream end of the left and right sheet pile portions. The buttocks are formed,
2. The cloth according to claim 1, wherein a flange formed at left and right corners of the upstream steel shell wall and a flange of the joint spacer are fitted to form a joint joint. Beam buttress type open dam.   The plurality of vertical beams are supported by a horizontal beam supported horizontally on the upstream side of the horizontal beam on a notch portion formed in a cylindrical portion of a joint spacer of a joint spacer column. The cross beam buttress type open embankment according to claim 2.   The left and right side steel shell walls of the saddle wall are fixed to left and right flank members disposed horizontally at intervals in the vertical direction on the inner surface, and the left and right flank members are joined to each other by tie materials. The cross beam buttress type open embankment according to claim 2 or 3, wherein the cross beam buttress type open embankment is provided.