JPH0721176B2 - Sliding scour prevention device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a slide type scour prevention device for preventing scour of a river bed ground on the downstream side of a dam structure or scour of a water bottom ground near a revetment structure. It is about.

[Conventional technology]

Conventionally, in order to prevent scouring of the river bed ground on the downstream side of the dam structure or to prevent scouring of the water bed ground near the revetment structure, the river bed ground or water bed ground at the scouring prevention place should be (1) Scour preventive means for laying out gabions formed by filling stones in iron wire bags, and (2) Scour preventive means for placing scour preventive boxes constituted by filling stones in water-permeable steel boxes. Has been adopted.

(3) As disclosed in Japanese Patent Laid-Open No. 55-95706, a bolt or a connecting member is attached between connecting brackets arranged inside and outside of a steel box body filled with stones, It is also known that the box-making bodies are connected to each other.

[Problems to be Solved by the Invention]

In the case of the scour preventive means of the above (1), the iron wire corrodes at an early stage, so that it has a drawback that durability is short. Further, in the case of the scour prevention means of the above (2), when the riverbed ground at the lower downstream side of the scour prevention box or the water bottom ground at the lower offshore side of the scour prevention box is scourd, the bottom of the scour prevention box is The scouring of the ground spreads, and the part of the scouring prevention box that is not supported by the ground expands.Therefore, a large load of a large amount of stone acts as a bending force on the water-permeable steel box, and The steel box may be damaged.

Further, in the case of (3), since it is necessary to dispose the connecting bracket inside the steel box body filled with stones, when the adjacent steel box bodies move up and down, the steel box bodies are moved. The connecting bracket in the body interferes with the stone filled in the steel box body, which may prevent the steel box bodies from moving up and down.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a slide type scour prevention device that can advantageously solve the above-mentioned problems.

[Means for Solving the Problems]

In order to achieve the above object, in the slide type scour prevention device of the present invention, a fixed scour prevention box 3 including a water-permeable steel box body 1 and stones 2 filled therein is used for dam construction. The movable scour prevention box 7 which is placed on the bed of the river close to the downstream side of the object 4 and comprises the water-permeable steel box body 5 and the stones 6 filled therein is the fixed scour prevention box. 3 is placed on the bed of the river in the vicinity of the downstream side, and steel brackets 19 projecting upstream are fixed to both sides of the upper part of the movable scour prevention box 7 on the upstream side in the river width direction. On the protruding part of
Steel guide members 20 having a circular cross section are fixed, and steel vertical guide frame members 23 are fixed on both sides of the fixed scour prevention box 3 on the downstream side in the river width direction. The frame member 23 is arranged and connected in the groove.

Further, a fixed scour prevention box 3 composed of a water-permeable steel box body 1 and stones 2 filled in the water-permeable steel box body is placed on the water bottom ground in the vicinity of the revetment structure 8 to form a water-permeable steel box body. A movable scour preventive box 7 composed of 5 and stones 6 filled therein is placed on the bottom of the sea near the offshore side of the fixed scour preventive box 3, Steel brackets 19 projecting to the land side are fixed to both sides in the lateral direction of the upper part on the land side, and steel guide members 20 having a circular cross section are fixed to the projecting portions of the brackets 19. The vertical guide members 23 made of steel are fixed to both sides of the offshore end in the horizontal direction, and the guide members 20 are arranged in the groove of the vertical guide frame member 23 and are connected to each other. Can be achieved.

〔Example〕

 The present invention will now be described in detail with reference to the illustrated example.

1 to 8 show an embodiment of the first invention, in which a steel frame material is welded or joined by bolts to form a box-shaped frame body 9. A large number of steel intermediate frame rods 10 are fixed to the peripheral wall and the bottom by bolts to form a water-permeable steel box body 1 having an open top. A fixed scour preventive box 3 is configured by filling with the class 2 and a large number of steel upper frame rods are fixed to the upper part of the water-permeable steel box body 1 by bolts.

Also, steel frame materials are welded or joined by bolts,
The box-shaped frame body 11 is configured, and on the lower side of the upstream side of the box-shaped frame body 11, an upstream side inclined portion 12 that is inclined so as to be displaced toward the downstream side from the upper portion to the lower portion is provided, and A large number of steel intermediate frame rods 13 are fixed to the wall portions on both sides of the box-shaped frame body 11 in the river flow direction (front-back direction), and a plurality of steel-made intermediate frame rods 13 are formed on the bottom portion and the inclined portion 12 of the box-shaped frame body 11. An intermediate frame rod 14 is fixed, and a wire mesh 15 made of expanded metal is fixed to the wall portions on both sides of the box-shaped frame body 11 in the river direction (horizontal direction), and the upper portion is open, and is made of water-permeable steel. The box body 5 is formed, and the movable scour prevention box 7 is formed by filling the water-permeable steel box body 5 with stones 6 made of crushed stone. Steel upper frame rod
16 is fixed by a bolt 17.

The fixed scour prevention box 3 is placed close to the downstream side of the dam structure 4 and placed on the riverbed 18, and the movable scour prevention box 7 is placed downstream of the fixed scour prevention box 3. Steel brackets 19 projecting upstream are welded on both sides of the movable scour prevention box 7 at the upper part of each movable scouring preventive box 7, which are arranged close to each other in two rows and are placed on the riverbed ground 18. The bracket 19 is fixed by a steel guide member 20 having a circular cross section to the protruding portion of the bracket 19.
A threaded rod 21 connected to the is inserted, and the guide member 20 is fixed to the bracket 19 by a nut 22 screwed to the threaded rod 21.

Steel with a groove-shaped cross-section that opens in the river width direction at both the downstream end of the fixed scour prevention box 3 and the downstream end of the upstream movable scour prevention box 7 in the river width direction. The vertical guide frame material 23 is fixed by bolts 24, the guide member 20 is arranged in the groove of the vertical guide frame material 23, and stones 25 are filled between the fixed scour prevention box 3 and the dam structure 4. ing.

The water-permeable steel box body 1 to which the steel vertical guide frame member 23 is fixed and the water-permeable steel box body 5 to which the guide member 20 and the vertical guide frame member 23 are attached are manufactured in advance in a factory or on land. The stones 2 and 6 may be filled into the water-permeable steel box bodies 1 and 5 on land near the site where the scour prevention device is installed.
After installing 1,5 at the predetermined position of the riverbed ground 18, the box body
Stones 2,6 may be filled in 1,5. As the stones 2 and 6, crushed concrete lumps may be used.

At the beginning of installation of the slide type scour prevention device, the fixed scour prevention box 3 and each movable scour prevention box 7 are placed side by side on the surface of the substantially flat river bed ground 18, and the slide type scour prevention device is provided on the downstream side. When the riverbed ground 18 is scoured and the scouring reaches the lower part of the movable scouring preventive box 7, as shown in FIG. 7 and FIG. The movable scour preventive box 7 on the side is moved downward and slightly rotated to the downstream side around the guide member 20, and the movable scour preventive box 7 on the upstream side is lowered with respect to the fixed scour preventive box 3. Further, the movable scour prevention box 7 on the upstream side can also rotate on the downstream side around the guide member 20.

When the movable scour preventive box 7 descends with respect to the fixed scour preventive box 3, the movable scour preventive box 7 is downwardly bent and connected to the downstream side of the fixed scour preventive box 3. The scouring of the riverbed ground 18 below the fixed scour prevention box 3 is prevented by 7.

In the case of this embodiment, the number of the movable scour prevention boxes 7 arranged in the river direction may be one, or may be three or more.

FIG. 9 to FIG. 12 show an embodiment of the second invention, in which the fixed scour prevention box 3 is arranged close to the revetment structure 8 and placed on the seabed 26, and movable scour is carried out. The preventive box 7 is arranged close to the offshore side of the fixed scour preventive box 3, and
The steel vertical guide frame member 23 is fixed to the offshore side end of the fixed scour prevention box 3, and is mounted on the movable scour prevention box 7.
A steel bracket 19 protruding toward the land side is fixed to the upper part of the land side end of the guide member 20, and the guide member 20 is fixed to the protruding portion of the bracket 19, and the guide member 20 is the vertical guide frame member 23. Although it is arranged in the groove, other configurations and operations are the same as those in the embodiment of the first invention.

9 and 10 show the initial state of the installation of the slide type scour preventive device, and FIGS. 11 and 12 show the state where the movable scour preventive box 7 is lowered by the scour of the water bottom ground 26. There is. When carrying out the second invention, a plurality of movable scour prevention boxes 7 may be arranged side by side toward the offshore side, as in the case of the embodiment of the first invention.

As in the above-mentioned embodiment, if the inclined portion 12 is provided at the lower part of the movable scour prevention box 7 on the fixed scour prevention box side, the bed ground
The movable scour prevention box 7 can be grounded in a stable state even if the surface of the ground 18 or the water bottom ground 26 is inclined by scour.

When carrying out the present invention, a plurality of steel intermediate frame rods may be welded or fixed to the wall portions on both sides in the river direction of the box-shaped frame body 11 by welding or bolts, and the wire net 15 may be omitted.

[Effects of the Invention] Since the present invention is configured as described above, it has the effects described below.

When the river bed ground 18 or the water bottom ground 26 is scourd and the scour reaches the lower part of the movable scour prevention box 7, the movable scour prevention box 7 descends with respect to the fixed scour prevention box 3 and is fixed there. Since a scour prevention barrier consisting of the movable scour prevention box 7 is automatically formed at the end of the scour prevention box 3, the riverbed ground 18 or the submarine ground 26 below the fixed scour prevention box 3 is washed. Since the movable scour prevention box 7 can be rotated downward with respect to the fixed scour prevention box 3 because the movable scour prevention box 7 can be prevented from being dug, the scour at the bottom of the movable scour prevention box 7 is prevented. Even if the surface of the river bed ground 18 or the water bed ground 26 is inclined, the movable scour prevention box 7 is automatically turned downward to move the river bed ground 18 or the water bed ground.
26 can be grounded in a stable state, and since the movable scour prevention box 7 descends with respect to the fixed scour prevention box 3,
The downward protrusion amount of the movable scour preventive box 7 from the fixed scour preventive box 3 is increased so that the riverbed ground 18 below the fixed scour preventive box 3 is increased.
Alternatively, it is possible to reliably prevent scouring of the water bottom ground 26.

Further, particularly in the case of the present invention, the steel vertical guide frame member 23 is fixed to the fixed scour preventive box 3, and the steel guide member on the movable scour preventive box 7 side is provided in the groove of the steel vertical guide frame member 23. Since the 20 are arranged and connected, the steel guide member 20 can surely descend along the vertical groove of the steel vertical guide frame member 23 without interfering with the stone in the fixed scour prevention box 3. At the same time, the movable scour prevention box 7 can be rotated, so that the movable scour prevention box 7 can be reliably lowered or rotated with respect to the fixed scour prevention box 3.
It is possible to automatically form a scouring wall for preventing scour.

[Brief description of drawings]

1 to 8 show an embodiment of the first invention, and FIG. 1 is a side view of a slide type scour prevention device, and FIG.
The figure is a plan view thereof, FIG. 3 is a sectional view taken along the line AA of FIG. 2, FIG. 4 is a front view of a slide type scour prevention device, and FIG. 5 is an enlarged slide part of the slide type scour prevention device. 6 is a schematic side view showing the initial state of installation of the slide type scour prevention device, FIG. 7 is a schematic side view showing the state of the slide type scour prevention device after scour, FIG. 8 is a side view showing a state of the movable scour prevention box after scour. 9 to 12 show an embodiment of the second invention, FIG. 9 is a schematic side view showing the initial state of installation of the slide type scour preventive device, and FIG. 10 shows a part thereof. FIG. 11 is an enlarged side view, FIG. 11 is a schematic side view showing a state of the slide type scour prevention device after scour, and FIG. 12 is a side view showing a part of the enlarged view. In the figure, 1 is a water-permeable steel box, 2 is stone, 3 is a fixed scour prevention box, 4 is a dam structure, 5 is a water-permeable steel box, 6
Is a stone, 7 is a movable scour prevention box, 8 is a revetment structure, 9 is a box frame, 10 is an intermediate frame rod, 11 is a box frame, 12 is an inclined part, 13
Reference numerals 14 and 14 are intermediate frame rods, 15 is a wire net, 16 is an upper frame rod, 18 is a riverbed, 19 is a bracket, 20 is a guide member, 23 is a vertical guide frame material, and 26 is a submarine ground.

Claims (2)

[Claims] 1. A fixed scour prevention box 3 comprising a water-permeable steel box 1 and stones 2 filled therein is placed on the bed of the river in the vicinity of the downstream side of the dam structure 4. , Water-permeable steel box 5
A movable scour prevention box 7 composed of and stones 6 filled therein is placed on the riverbed in the vicinity of the downstream side of the fixed scour prevention box 3 and upstream of the movable scour prevention box 7. Steel brackets projecting upstream, on both sides in the width direction of the upper part of the side
Steel guide members 20 having a circular cross section are fixed to the protruding portions of the brackets 19, and steel vertical guide frames are provided on both sides in the river width direction at the downstream end of the fixed scour prevention box 3. A slide type scour prevention device in which a member 23 is fixed and the guide member 20 is arranged and connected in a groove of a vertical guide frame member 23. 2. A fixed scour prevention box 3 comprising a water-permeable steel box body 1 and stones 2 filled therein is placed on the water bottom ground in the vicinity of the revetment structure 8 to provide water permeability. A movable scour prevention box 7 composed of a steel box body 5 and stones 6 filled in the box body 5 is placed near the offshore side of the fixed scour prevention box 3 on the submarine ground, Steel brackets 19 projecting to the land side are fixed to both lateral sides of the land-side upper part of the prevention box 7, and a steel guide member having a circular cross section is attached to the projecting portion of the bracket 19.
Steel vertical guide frame members 23 are fixed to both sides of the fixed scour prevention box 3 on the offshore side in the lateral direction, and the guide members 20 are arranged in the grooves of the vertical guide frame members 23. Slide-type scour prevention device that is connected and connected.