JPH06330515A - Permeable driftwood occurrence control device - Google Patents

Abstract

PURPOSE:To provide a permeable driftwood occurrence control device, to reduce the corrosion of a cliff in the case of a flood while keeping a scene of the cliff or natural environment and, at the same time, to make it possible to prevent earth and driftwood from flowing out to the course of a river. CONSTITUTION:Excavated spaces are formed in cliffs, etc., to arrange base frames 3 and 3, and base members 4 and 4 at right angles to them are mounted. Column members 6 and 6 are fixed on them to form triangular frame bodies 5 and 5, adjacent triangular frame bodies 5 and 5 are connected to each other with beam members 7 and, at the same time, batten members 13 and 13 are mounted between adjacent column members 6 and 6. Bedding cages 18 are used to construct a driftwood accurrence control device 1. Even if a river rises to have running water rolling in, the driftwood occurrence control device 1 displays energy dissipation effect to ease the corrosion of the cliffs. While, even if the flow of earth or driftwood occurs by an earthquake, etc., driftwood, etc., are caught by the driftwood occurrence control device 1 to prevent them from flowing out to the course of the river, so that bridges carried away by the flood can be reduced. The installation of the driftwood occurrence control device 1 is not accompanied by any natural destruction, and living environment of plants and animals is also maitained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission type driftwood generation suppressing work, and more specifically, it suppresses the formation of driftwood by reducing the erosion of riverbanks and shores, and is caused by floods, strong winds, earthquakes and the like. The present invention relates to a driftwood deterrent work capable of catching fallen trees and controlling sediment-related disasters to realize conservation and harmony of natural environments and landscapes.

[0002]

2. Description of the Related Art When a hillside or a slope on a shore is eroded or collapsed over the years, sediment and fallen trees are produced and flow out into a river. If driftwood or the like gets stuck in a narrowed part of a bridge or a river, it will flood the bridge girder and induce flooding of earth and sand, causing serious damage to houses, fields, roads, etc., and in the worst case, killing people's lives and causing a great social impact. Will cause damage. Not only that, but the natural environment is also destroyed, and a long-term restoration project is inevitable for its recovery. There are driftwood prevention works and driftwood capture works as driftwood countermeasure facilities to prevent such damage, and they are distinguished as follows. Driftwood generation deterrent works include slope stabilization works, revetment works, and floor solidification works. By appropriately combining them, the erosion of the shore and the riverbed can be reduced, and the protection and fixing of the shore and the like can be achieved to generate sediment and driftwood. Function to prevent. On the other hand, the driftwood catching work is a transmission type sabo dam or a partial transmission type sabo dam installed in the debris flow section, and functions to capture the driftwood when it is placed in the sweep section. The seawall directly protects the slope of the riverbank from flood flow, and recently natural stones such as cobblestone and concrete or concrete products such as concrete blocks have been used. Note that gabion, which is highly evaluated for its flexibility and landscape, has a steel wire that is easily corroded and cut, and cobblestone and cobblestone as filling materials are becoming difficult to obtain. It is becoming less used except for construction work.

[0003]

[Problems to be Solved by the Invention] Revetment as a measure against driftwood is not only limited to disaster prevention, but socially it is necessary to consider the survival of animals and plants and harmony with the natural environment. However, when constructing a revetment, conventional construction involves cutting the vegetation on the slope of the riverbank and excavating the ground, which weakens the strength of the ground and causes problems such as loss of the natural environment. is there. In addition, revetment made of concrete lacks consideration for harmony with the natural environment, and has a problem in terms of protection of flora and fauna. On the other hand, revetments are often deeply excavated and damaged due to a concentrated flow.
It is necessary to take measures such as protecting the foundation part with rooting and reducing the concentration of running water. Therefore, it is desirable to develop a new construction method that keeps the shore in a natural state, reduces erosion on the shore, and suppresses the occurrence of driftwood. In the development, it is also necessary to reduce the energy of the flow concentrated on the shore and indirectly protect the shore. By the way, in a rapid river, it is assumed that it will be used for water control at the place where the debris flows, the root block, and the deadline for the breakwater.
The cow frame and Kawakura, which are made by combining long logs, and the middle sacred cow and the great sacred cow, which hold three pairs of gastric trees with a gabion, have been used since ancient times. However, these are traditional ones and cannot be manufactured in large quantities and quickly. Therefore, they are not suitable for manufacturing as industrial products. In the river, a secondary flow occurs in the transverse direction in addition to the main flow, which is combined with the main flow to form a spiral flow. This secondary flow is highly developed at the curved part and causes local scour on the outer bay side. In order to reduce the local scour depth, a vane method for depressing the secondary flow has been proposed (Civil Engineering Material Vol. 25, No. 12, 1985). This is one in which several plate-shaped vanes are placed at intervals on the outer bay side of the curved part of the river channel so as to direct the flow of river water.
However, there are various problems and difficulties in the method of installing the vane in the river channel, and it has not been put to practical use in the rapid river. The present invention has been made in view of the above problems, and an object thereof is to reduce the erosion of a riverbank or the like and suppress the occurrence of driftwood, and at the same time, induce factors other than floods,
For example, it has a sabo function for the prevention of sediment-related disasters that also has the function of capturing fallen trees caused by strong winds and earthquakes, conservation and creation of the natural environment, and harmony with the natural environment and landscape. It is to provide a type of driftwood deterrent work.

[0004]

The present invention is constructed in a turret shape and fixed by a futon basket so as to be immovable, and fallen trees and earth and sand flow into a river channel when flooding occurs and driftwood is generated. It is applied to the driftwood prevention work that is designed to prevent The feature is that, with reference to FIG. 1 and FIG. 5, the base frame 3, which is arranged in parallel with the excavation space 16 formed in the front surface of the riverbank 21 or the like.
3 and a plurality of base members 4 mounted orthogonally to the base frame 3 and fixed to the base frame 3.
4 and column members 6 and 6 which are fixed to both ends of the base member 4 and are inclined and rise from each end so as to face each other and form a triangular frame 5 together with the base member 4 and the base member 4. A beam member 7 that connects the upper ends of the column members 6 and 6 that face each other, extends parallel to the base frame 3, and is attached across the tops 5a and 5a of the adjacent triangular frames 5 and 5, The pillar members 6, which are located at the intermediate height position of the pillar members 6 and are located on the same plane side of the adjacent triangular frame bodies 5, 5.
The crosspieces 13 and 13 which are attached across 6 and form the water-permeable space 15 between them, and the base frame 3 which is located on the side of the triangular frame 5 are pressed from the riverbank 21 and the like. That is, the futon basket 18 is provided to prevent the washing out. The crosspiece members 13 and 13 may be attached to the pillar members 6 and 6 at close intervals to each other to depress the secondary flow of the river water (see FIG. 7). Trees 23 can be planted in the futon basket 18 located between the adjacent triangular frames 5 and 5 (see FIG. 6). As shown in FIG. 9, a flat plate-shaped vane 22 is hung on the beam member 7, and the lower end of the vane 22 is fixed by being sandwiched between the futon baskets 18, 18 arranged on both sides to prevent the secondary flow of river water. It can be depressurized. It is preferable that the vane 22 has a rectifying hole 15A formed therein. A plurality of vanes 22 may be arranged between the triangular frame bodies 5 and 5, as shown in FIG. 10. Then, the vanes 22A and 22A arranged between the triangular frames 5 and 5 may be arranged so that the downstream end thereof protrudes toward the river 20 side. As shown in FIG. 8, by arranging the base frames 3 and 3 so that the downstream ends thereof protrude toward the river channel 20, it is possible to return the flow rushing to the riverbank 21 to the river channel 20.

[0005]

[Function] The excavation space 16 having the height of the futon basket 18 is formed on the shore 21. The materials constituting the driftwood generation suppressing work 1 are carried into the mountain bank 21, and the base frames 3 and 3 are arranged in the excavation space 16. The base members 4 and 4 are attached to the base frames 3 and 3, and the pillar members 6 and 6 are also mounted and fixed thereon. The futon basket 18 is arranged between the triangular frames 5 and 5 formed by the base member 4 and the pillar member 6. Then, the beam member 7 is passed over and fixed to the top portions 5a, 5a of the triangular frame bodies 5, 5, and the crosspiece members 13, 13 are attached between the pillar members 6, 6.
In this way, when the transmission type driftwood generation suppressing work 1 is arranged along the river in front of the riverbank 21 or the like, the running water that flows toward the riverbank 21 when the river increases is the pillar member 6 or the cross member 13. It is depressurized due to such factors as flowing through the permeable space 15,
Erosion of the shore 21 and the bed is reduced. On the other hand, even if sediment flow or fallen trees occur due to strong winds or earthquakes as well as floods, driftwood generation deterrent work 1 prevents runoff to the river channel, and it is possible to reduce the occurrence of driftwood and let the bridge girder run out. Avoided as much as possible. If the space between the crosspiece members 13, 13 attached between the pillar members 6, 6 is made close to each other to make the water permeable space 15 small, the momentum of the flowing water toward the shore 21 or the like is significantly reduced. Above all, if several are arranged side by side on the outer bay side of the curved river channel, the shoreline on the outer bay side 21
The erosion of the river can be stopped and the meandering of the river can be suppressed. If trees 23 such as willows are planted in the futon basket 18 located between the triangular frames 5 and 5, the force of the running water can be weakened by the branches and leaves of the willows grown during a flood or the like.

A flat plate-shaped vane 22 is hung on the beam member 7 and the lower end of the vane 22 is a futon basket 18, 18.
If fixed by sandwiching with, the secondary flow of the river water is de-energized by the vanes 22, and the erosion of the shore 21 due to the concentration of the flow is reduced. If the rectifying holes 15A are formed in the vanes 22, the permeability can be obtained and the force acting on the vanes 22 can be reduced. Therefore, the driftwood generation suppressing work 1A can exert its function over a long period of time. Even when the vanes 22 are formed in a strip shape and a large number are arranged between the triangular frames 5 and 5, the driftwood generation suppressing work 1A having transparency is obtained. A plurality of vanes 22A, 22A arranged between the triangular frames 5, 5
Is arranged so that the downstream end thereof protrudes toward the river channel 20, the flowing water hitting the vanes 22 acts so as to be returned to the river channel 20, and erosion of the riverbank 21 and the like can be reduced.
In any of the driftwood generation suppressing works 1 and 1A described above, if the downstream ends of the base frames 3 and 3 are arranged so as to protrude toward the river channel 20, the flow toward the riverbank 21 or the like is reduced or reduced. be able to.

[0007]

EFFECTS OF THE INVENTION According to the present invention, the earth and sand have the function of reducing the energy of running water to reduce erosion on the shore, suppress the generation of driftwood, and at the same time capture trapped trees caused by strong winds or earthquakes. It can be a sabo facility for disaster prevention. Also, vegetation cutting and rock excavation are avoided,
Maintaining the landscape and protecting the environment where flora and fauna can survive,
Harmony with nature is realized. When a large number of crosspiece members are attached to the column members at close intervals, it becomes a driftwood generation suppressing work that also has a secondary flow suppressing function as a vane structure. If trees are planted in the driftwood prevention work, the riverbanks will be greened, and the branches and leaves can also function to depress the running water. If a vane is attached to the driftwood generation prevention work, the flowwater that flows toward the outer bay side where the river channel is curved can be diminished, and it can act as a vane work that reduces erosion on the shore. The placement of the vanes in the river channel is facilitated by the installation form as a driftwood prevention work, and the runoff is also avoided. Permeability can be exhibited by forming rectifying holes in the vanes, the force acting on the vanes can be reduced, the size and rigidity of driftwood generation control work can be prevented from increasing, and the amount of steel input can be reduced. If a large number of vanes are attached to the driftwood prevention work such as strips, a water-permeable space is naturally obtained, and the same effect as in the case where the flow regulating holes are provided is exhibited. When the large number of vanes are tilted with respect to the river channel, the action of returning the water flowing toward the stream to the river channel is obtained.
Erosion of the banks is reduced. The same applies when the driftwood prevention work itself is inclined to the river.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a transmission type driftwood generation suppressing work according to the present invention will be described below in detail with reference to the drawings. Figure 1
2 is a front view of the driftwood generation control work, FIG. 2 is a plan view thereof, FIG. 3 is a side view thereof, FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. 1, and FIG. 5 is a schematic view showing a state installed on a shore. Is. This is an immovable state in which steel materials are assembled into a turret and fixed to a riverbank or a riverbank with a futon basket, and it is possible to prevent driftwood from occurring when the water level increases or an earthquake occurs. As shown in FIGS. 1 to 4, the deterrent work main body 2 constituting the driftwood deterrence work 1 installed along the riverbank 21 as shown in FIG. 6 includes a plurality of base frames 3 and respective base frames 3. Base members 4A to 4C which are mounted on and orthogonal to each other
And column members 6A to 6C fixed thereto, and a beam member 7 connecting the upper ends of the column members 6 and the like.

As shown in FIG. 5, the base portion of the restraint work main body 2 is two parallel base frames 3 and 3 arranged in the excavation space formed in the front surface of the shore 21 or the like. This includes, for example, a total length L ₁ (see FIG. 1) of 7 m and a height H ₁
Is 200 mm and the width W ₁ (see FIG. 2) is 200 mm, and H-shaped steel is used. The base member 4A to 4C is mounted on the flange and the web surface as shown in FIG. Welded reinforcing members 3a are attached one each inside and outside. Further, four bolt holes are provided on the flange surface with the reinforcing members 3a interposed therebetween. The base members 4A to 4C, which form the triangular frames 5A to 5C together with the pillar members 6 and are placed orthogonal to the base frames 3 and 3, are made of H-shaped steel having the same dimensions as the base frames 3 and 3. The total length L ₂ (see FIG. 2) adopted is about 4.5 m. Two reinforcing members 4a (see FIG. 1) are attached to the left and right sides of the web at positions where the base members 4A to 4C contact the upper surface of the base frame 3. Four bolt holes are provided in the lower flange sandwiching each reinforcing member 4a, and the base member 4 is fixed to the base frame 3 by the bolt 8. As shown in FIG. 3, the base members 4A-
The plurality of pillar members 6A to 6C forming the triangular frames 5A to 5C together with the base members 4A to 4C incline so as to face each other from both ends of 4C, and
It is a square pipe of less than 00 mm. A flange 9 is attached to the lower end surface by welding or the like, and a flange 10 is also attached to the upper end surface.
Are integrated. Then, the base portion of the pillar member 6 is fixed to the base member 4 by the bolts 11 inserted into the bolt holes provided in the flange 9 and the bolt holes provided in the upper flange of the base member 4. In addition, the flange 10 is provided with a bolt hole having a margin such as a long hole so as to be bolted to the beam member 7 and to enable fine adjustment later.

On the other hand, a beam member 7 connecting the upper ends of the column members 6A, 6A to 6C, 6C facing each other on the base members 4A to 4C and extending in parallel to the base frame 3 is provided as shown in FIG. , The tops 5 of adjacent triangular frames 5A-5C
It is attached across a and 5a. This beam member 7 is
It consists of two long main beam members 7A and three auxiliary beam members 7B. 20 for both the main beam member 7A and the auxiliary beam member 7B.
Square pipes of a little less than 0 mm are used, and both ends of each pipe are closed by a cover 7a that prevents water and dust from entering. The main beam member 7A is long enough to connect the column members 6 and 6 of the adjacent triangular frame members 5 and 5, and the auxiliary beam member 7B is a short pipe having the same width as the flange 10. The auxiliary beam member 7B of the pillar member 6B located in the center is integrated over the two main beam members 7A and 7A. At the construction site, the beam member 7 prefabricated in the factory so that the two main beam members 7A and the three auxiliary beam members 7B are integrated is
The facing flanges 10 and 10 of the pillar members 6A to 6C (see FIG. 3).
It is fixed to the pillar member 6 through the eight bolts 12 inserted into the bolt holes of the flange 10 and the bolt holes provided in the main beam member 7A and the auxiliary beam member 7B. . As shown in the phantom line in FIG. 6, when the river is significantly flooded, in order to prevent sediment and fallen trees from flowing into the channel 20, as shown in FIG.
It is provided on the pillar members 6 and 6 which form 5. That is, the mounting plate 14 is welded toward the outer surface from the upper side of the pillar members 6A to 6C to the substantially central portion and straddles the mounting plates 14 and 14 so that the cross-section member 13 has a U-shaped cross section. But,
It is bolted on the same side of the adjacent triangular frames 5 and 5. Thus, at the intermediate height position of the pillar member 6, the crosspiece members 13 and 13 are arranged at the coarse pitch p shown in FIG.
Water-permeable spaces 15, 15 are formed between them. Therefore, the fallen trees that cannot pass through the permeable spaces 15, 15 are the rivers 2.
While it is prevented from flowing out to 0, the running water rushing to the shore 21 can be deenergized by the crosspiece members 13, 13.

Such a transmission type driftwood generation suppressing work 1 is
It will be placed in front of the shore 21 by the procedure described below,
It will be installed at a position where it will not be submerged in river water when the river is not flooded. On the other hand, when water increases or a flood occurs, most of it is submerged. Therefore, as shown in FIG. 1, a futon basket that is located inside and outside the triangular frames 5 and 5 and presses the base frames 3 and 3 so as not to be washed away. Many 18 are loaded. The soil around it is backfilled to the same extent as the upper surface of the futon basket 18 after the riverbed stones 17 have been filled. In this example, the futon basket 18 has a height H _{3 of} about 1 m and a width W.
₃ (see FIG. 2) is 1.2 m and length L ₃ (see FIG. 3) is 2
A rectangular parallelepiped of m is used. Of course, the width is about 2
A material having a length of m or a material having a length of 3 m is appropriately selected and used.

Driftwood generation suppression work 1 constructed as described above
Is the riverbank 21 of the river 19 (see FIG. 6) as follows.
It is installed in the area to reduce the erosion of the shore and prevent the occurrence of driftwood. It also catches fallen trees caused by floods, strong winds, earthquakes, etc. and prevents sediment-related disasters, preserving the natural environment and maintaining the natural landscape. You can harmonize. First, in a factory, the base frame 3 that constitutes the restraint work main body 2, the base member 4 and the column member 6 that form the triangular frame, and the beam member 7 and the cross member 13 are each cut into a predetermined length. It is made of steel or square pipe, and the flange of the connecting part that is required during assembly is attached by welding. While the material is transported to the shore 21 shown in FIG. 6, the depth in the front of the shore 21 is almost equal to the height of the futon basket 18 and is wide enough to install the driftwood prevention work 1. An excavation space 16 is formed. The bottom soil of the excavation space 16 is evenly leveled, and the two base frames 3 and 3 are arranged therein at substantially the same intervals as the width of the triangular frame body 5 so as to be substantially parallel to the river channel 20. Three base members 4 and 4 are fixed using bolts 8 and 8 so as to cross the base frames 3 and 3 at right angles, and both ends of the base member 4 are fixed by a crane. The lower end of the suspended pillar member 6 is attached by bolts 11, 11. In this state, the futon baskets 18, 1 are placed on the base frames 3, 3.
Although the column members 8 are mounted, each column member 6 is separately supported so that the column members 6 do not shake or shake during the work. After evacuating the crane, the steel basket for the futon basket 18 is placed on the base frame 3. As shown in FIG. 2, between the two adjacent triangular frames 5 and 5, four steel cages are arranged so that the six steel cages are rectangular when viewed in plan, if the length is 3 m. Deploy. As shown in the drawing, if the base frames 3 and 3 are protruded from the base members 4 and 4, three or two are arranged outside the triangular frame 5. Then, filling materials such as chestnut stones and river bed stones 17 are put into each steel basket, and when the steel basket is full, the steel basket is covered or left as it is. In this state, each triangular frame 5, 5
The beam member 7 is carried by a crane to the tops 5a, 5a of the pillars, and the bolts 12, 1 are attached to the flange 10 at the upper end of the pillar member 6.
Fixed by 2. Since the auxiliary beam member 7B is attached below the main beam member 7A, each flange 10 and the auxiliary beam member 7 are
B is also bolted. The temporary support material that supports the pillar member 6 is removed, and the presence of the pillar member 6 causes the futon baskets 18 and 1 to be removed.
The riverbed stones 17 and the like are packed in the voids formed between the eight. Finally, the crosspiece members 13, 13 are attached between the pillar members 6, 6 on the same surface side of the adjacent triangular frame bodies 5, 5. In this way, one driftwood generation suppression work 1 is constructed,
Other driftwood generation suppressing works are arranged along the riverbank 21 as many times as necessary so as to be continuous with or at intervals. Then, the periphery of the excavation space 16 is backfilled.

Driftwood generation suppression work 1 constructed in this way
If there is no increase in water in the river, the upper part of the futon basket 18 is exposed from the shore 21. On the other hand, when the river is flooded and the shore 21 is flooded, the driftwood generation suppressing work 1 is in a semi-destructed or fully submerged state. As shown in FIG.
The running water Q rushing to the shore 21 in the lateral direction with respect to the main stream N passes through the permeation spaces 15, 15 of the driftwood generation suppressing work 1,
Its momentum is significantly reduced. The erosion of the shore 21 is reduced by the depressing effect of this transparent revetment, and the collapse of the shore and the occurrence of fallen trees are reduced as much as possible. And the shore 21
There is little change in the riverbed along the ridge, and vegetation can enter the space between the riverbank 21 and the driftwood generation suppression work 1. If vegetation progresses over the years, it will effectively protect the riverbank 21 and the bed. In addition, a natural environment suitable for the habitation of plants and animals will be created. In addition, the main body of the deterrent is a futon basket 18
Since it is fixed by using, the excavation of the foundation can be limited to the minimum level of leveling. On the other hand, when a tree on the shore 21 collapses or the earth and sand collapse due to the occurrence of a strong wind or an earthquake, a large amount of fallen trees or trapped trees are captured by the pillar members 6, beam members 7, crosspiece members 13 of the driftwood generation suppressing work 1. Sediment is prevented from flowing into the river 20. In this way, the expansion of the disaster is avoided, but not only that, large-scale construction that occurs in concrete revetments is not required, and tree cutting and extensive excavation of the ground are performed on the slopes of the banks. Can be avoided and the natural landscape can be maintained. In the case of a concrete revetment, running water causes a deep digging phenomenon in the foundation, but since it is buried in the riverbank 21, there is no deep digging, and no foundation work is required. You can Therefore, this also makes it possible to maintain the natural environment without significantly changing the habitat of the flora and fauna on the shore 21. Each member that forms the restraint work main body 2 that constitutes the driftwood generation restraint work 1 can be manufactured in advance in a factory with consistent dimensional accuracy, and the construction period can be shortened. In addition, the efficiency of the assembly work at the site can be achieved, and it can be quickly adopted as a construction method for disaster recovery work even in an emergency. Furthermore, by standardizing and mass-producing, the manufacturing cost can be reduced.

The assembly procedure described in the example of the driftwood generation suppressing work 1 is not limited to that. For example, when the pillar member 6 is placed on the base member 4, the pillar member 6 is fixed to a temporary degree, and the lower end portion of the pillar member 6 is fixed when the beam member 7 is attached after the futon basket 18 is arranged. You may In this case, it is not necessary to allow the bolt holes provided in the flange 10 to have a margin. Although the three triangular frames 5 and 5 forming the driftwood generation suppressing work 1 are fixed to the pair of base frames 3 and 3,
It may be two or four. further,
Although the base frame 3 projects to the side of the base member 4, the base members 4 and 4 may be fixed to the end portions of the base frames 3 and 3. The pillar member 6 may be fixed to the base member 4 in advance, the pillar member 6 may be placed on the base frames 3 and 3, and the futon basket 18 may be arranged before connecting the beam member 7 to the base member 4. It is also possible to fix 6 in advance, place it on the base frames 3 and 3, and then place the steel basket. In any case, the work procedure can be constructed in a smooth manner as the work procedure.

By the way, as shown in FIG. 6, trees 23 such as willow trees can be planted in the futon basket 18 located between the adjacent triangular frames 5 and 5. In that case, the willow may be planted in a decaying wooden box, and the box may be placed in a steel basket before the filling material is put in. With the passage of time, soil will infiltrate between the filling materials, and a growing environment protected by the restraining body will be obtained. In this way, not only will greening be achieved, but the branches and leaves of the willows that have grown will act to increase the roughness coefficient and reduce the flow velocity of river water during a flood, further promoting the function as a transparent revetment. become. The crosspiece 1
If the mutual intervals of 3 and 13 are made close to each other as shown in FIG.
The same effect as 2A (see FIGS. 9 and 10) can be exerted, and the effect of reducing the secondary flow of river water can be increased. That is, the force of the flowing water toward the shore 21 is significantly reduced, and if the rivers are arranged side by side on the curved river channel, the erosion of the shore 21 on the outer bay side can be reduced.
By the way, when the driftwood generation suppression works 1 and 1 are arranged side by side on the riverbank 21, for example, when the river channel is straight, as shown in FIG. It can be placed so that it sticks out. For example,
In FIG. 8, the angle is exaggerated, and it is an example in which the rivers are continuously installed. Can be returned to the mainstream N of the river 20 as indicated by an arrow M, and the erosion and collapse of the shore 21 can be reduced. The driftwood generation suppressing works 1 and 1 may be discontinuously arranged, or the individual driftwood generation suppressing works 1 may be inclined and the row of the driftwood generation suppressing works may be parallel to the river channel 20. Good.

FIG. 9 shows an example in which a vane 22 is attached to the inside of the driftwood prevention work 1A. The vane 22 is a single flat steel plate and is hung on the lower surface of the beam member 7 via a bracket. The lower end of the vane 22 is sandwiched and fixed by the futon baskets 18, 18 arranged on both sides, and the upper end is fixed by a bolt or the like. When such a vane 22 is attached, the above-mentioned crosspiece member 13 is not required or a crosspiece member 13 forming a large water-permeable space 15 is used. Driftwood generation suppression work 1A equipped with such vanes 22
Is installed in the river channel on the outer bay side where the river channel 20 is curved. That is, when the water flow increases, a secondary flow is generated transversely to the main flow, which is combined with the main flow to form a spiral flow. This secondary flow is highly developed at the curved part and causes local scouring on the outer bay side. However, since the vane 22 of the driftwood generation suppression work 1A greatly reduces the secondary flow,
Erosion of the shore 21 located on the outer bay side is reduced. As described above, if the vanes 22 are provided in the driftwood generation suppressing work 1A, it is possible to keep the vanes having a simple plate structure in an extremely stable state as compared with the case where the vanes are installed in the river channel. That is, since the deep excavation of the foundation of the driftwood prevention work 1A is reduced, it is possible to make the foundation part shallower than that of an ordinary revetment. As shown in the figure, if the flow regulating holes 15A are formed in the vanes 22, it becomes a transmissive revetment, and the collision of large gravel during outflow is reduced. It is also possible to prevent the driftwood generation suppressing work 1A from receiving a large force by the force of the flowing water, and it is not necessary to use a driftwood generation suppressing work having excessively high rigidity. Although one or two vanes 22 are employed in one driftwood generation suppressing structure 1A, strip-shaped vanes 22A may be used as shown in FIG. In such a driftwood generation suppressing work 1A, a plurality of triangular frames 5 are arranged between the vanes 22A and 22A, and the water permeable space 1 is provided between the vanes 22A and 22A.
5A and 15A will be naturally formed. In addition,
Although not shown, if the individual vanes 22A are attached so that their downstream ends project toward the river, that is,
If the vanes 22A and 22A are formed so as to form a row of blades, the same operation as in the case of FIG. 8 described above can be performed. Of course, this kind of driftwood prevention work 1
It is also possible to arrange a plurality of A's as shown in FIG.
In any case, the inclination angle of the vane 22A is
The shape of the river channel 20 and the tendency of flowing water at the time of rising water may be predicted and appropriately determined.

As described in detail above, by installing a driftwood prevention work as a transparent revetment on the front of the riverbank or in the curved river channel, the vegetation on the slope of the riverbank which is carried out by the conventional revetment work is installed. Logging and excavation of the ground are avoided, and the natural environment is maintained while maintaining the strength of the ground. In addition, the transmissive deterrent works not only prevent the outflow of sediment into river channels and the generation of driftwood, but also capture sediment flow and fallen trees due to wind, earthquakes, etc., which were not possible with conventional revetment works. it can. Thus, the transmission type driftwood generation deterrent work according to the present invention is not limited to the prevention of the driftwood generation, and it is also used as a method for fixing a constant waterway with debris flow dispersed trees or the like, or as a nursery or protection method for a dike, a forest, ,
It can be used as a low-water canal revetment with consideration for the fauna and flora habitat and landscape maintenance in the channel construction, and it has a wide range of application.

[Brief description of drawings]

FIG. 1 is a front view of a transmission type driftwood generation suppressing work.

FIG. 2 is a plan view of a driftwood prevention work.

FIG. 3 is a side view of a driftwood prevention work.

FIG. 4 is a sectional view taken along the line IV-IV of FIG.

[Fig. 5] Installation drawing of driftwood suppression work located on the shore.

FIG. 6 is a schematic diagram for explaining the condition when the water level is increased and for arranging trees in the driftwood generation suppression work.

FIG. 7 is a front view of a driftwood generation suppressing work in an example in which the crosspiece members are densely attached.

FIG. 8 is a plan view showing a state in which a large number of driftwood generation suppressing works are arranged so as to be inclined with respect to the river channel.

FIG. 9 is a side view of a driftwood generation suppressing work provided with a flat vane.

FIG. 10 is a front view of a driftwood generation suppressing work provided with a large number of strip-shaped vanes.

[Explanation of symbols]

1, 1A ... Driftwood generation suppression work, 3 ... Base frame, 4,
4A to 4C ... Base member, 5, 5A to 5C ... Triangular frame,
5a ... Top part, 6, 6A to 6C ... Column member, 7 ... Beam member, 1
3 ... Cross member, 15 ... Water permeable space, 15A ... Straightening hole, 16 ...
Excavation space, 18 ... Futon basket, 20 ... River, 21 ... Gorge,
22,22A ... Vane, 23 ... Tree (willow).

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Hideyuki Okada Inventor Hideyuki Okada 7-1, 1-1, Onoedori, Chuo-ku, Kobe-shi, Hyogo Within Kawatetsu Construction Materials Co., Ltd. (72) Shuji Nishikawa Ono-pattern, Chuo-ku, Kobe-shi, Hyogo 7-1, 1-1, Kawatetsu Building Materials Co., Ltd. (72) Inventor, Seikatsu Yamaguchi, 7-1, 1-1, Ono-dori, Chuo-ku, Kobe-shi, Hyogo Prefecture (72) Inventor, Hiroshi Suzuki Tokyo 3-4 Ichigaya Sadohara-cho, Shinjuku-ku, Tokyo Inside Sabo / Landslide Technical Center (72) Inventor Sohei Abe 3-4 Ichiya-Sadohara-cho, Shinjuku-ku, Tokyo Inside Sabo / Landslide Technical Center

Claims (8)

[Claims] 1. It is assembled in a turret shape and fixed by a futon basket so that it remains immovable, and prevents falling trees and sediment from flowing into the river channel and causing driftwood when the water level increases. In driftwood generation suppression work, a base frame arranged in parallel with the excavation space formed on the front surface of a mountain shore, and a plurality of base frames placed perpendicular to the base frame and fixed to the base frame. A base member, a pillar member fixed to both ends of the base member, rising from the respective ends in an inclined manner so as to face each other, and forming a triangular frame together with the base member; and a pillar facing the base member. A beam member that connects the upper end portions of the members, extends parallel to the base frame, and is attached across the top portions of the adjacent triangular frames, and is located at an intermediate height position of the column member. A crosspiece member having a plurality of rods mounted across straddling pillar members located on the same surface side of adjacent triangular frame bodies and forming a water-permeable space therebetween, and a base frame positioned on a side portion of the triangular frame bodies. It is equipped with a futon basket to prevent runoff from the shore, etc., and reduces the erosion of the shore by depressing the energy of the flowing water toward the shore, and prevents fallen trees that occur with earth and sand etc. A transmission type driftwood generation deterrent work characterized by being temporarily captured and accumulated so that it can be prevented from flowing into a river. 2. The permeation according to claim 1, wherein the crosspiece members are attached to the pillar members at a close interval to each other so that the secondary flow of river water can be deenergized. Driftwood generation suppression work. 3. The transmission type driftwood generation suppressing work according to claim 1, wherein trees are planted in the futon basket located between the adjacent triangular frames. 4. A flat plate-shaped vane is hung on the beam member, and the lower end of the vane is fixed by being sandwiched between the futon baskets arranged on both sides so that the secondary flow of river water can be deenergized. The transmission type driftwood generation suppressing work according to claim 1, wherein 5. The permeation type driftwood generation suppressing work according to claim 4, wherein the vane is formed with a straightening hole. 6. The transmission type driftwood generation suppressing work according to claim 4, wherein a plurality of the vanes are arranged between the triangular frames. 7. The transmission type driftwood generation suppressing work according to claim 6, wherein a plurality of vanes arranged between the triangular frames are arranged so that their downstream ends project toward the river side. . 8. The transmission type driftwood generation suppressing work according to claim 1, wherein the base frame is arranged so that a downstream side end thereof projects toward a river side.