JPS5998916A - Preventer for deposition of soil and sand on falling dam - Google Patents

Abstract

PURPOSE:To prevent the deposition of soil and sand on the downstream side of a falling dam by a method in which one end of a pipe is opened in water on the upstream side of the falling dam, and the other end of the pipe is opened in the soil and sand deposition area on the downstream side of the dam. CONSTITUTION:When a rubber dam 1 rises and also the amount of water is abundant, river water held in the rubber dam 1 flows from the intake opening 7a of a pipe into a pipe 7, reaches a blow-out port 7c adjacent to the top tiered part 3a of the river bed concrete, and is discharged from a blow-out port 7d directed toward the downstream side of river. Soil and sand 11 deposited on the top 3 of the river bed concrete are pushed down to the downstream side and discharged.

Description

[Detailed Description of the Invention] This is called a so-called rubber break. A flexible membrane weir with an undulating pattern,
This invention relates to a device that prevents earth and sand from accumulating on the downstream side of an undulating weir such as a steel overturning gate weir.

Expands and contracts by supplying and discharging fluids such as water and air.
F44 regular rubber weir, also known as ``flexible membrane weir'' and lower end σ
] For rivers with undulating weirs such as steel overturning gates that swing along the direction of the river flow around the central branch, the undulating weirs are erected during low flow periods, and the undulating weirs are erected during high flow periods. When a weir is laid down, the cross-sectional area of the river does not change much even in the vicinity of the weir, allowing water to flow smoothly and preventing flooding.

However, even when the undulating weir is erected, the water force may entrain sediment into the flowing water on the upstream side of the undulating weir, and it may cross over the undulating weir and reach the downstream side. The earth and sand that has passed over the undulating weir 2 will be deposited just downstream of the erected undulating weir due to the difference in specific gravity with the water. Moreover, some of the water that overflowed the undulating weir was diverted upstream. As a result, the sediment deposited just downstream of the undulating weir is not only pushed downstream by the water flow that overflowed the undulating weir, but is even further piled up by the upstream water flow. n. It's in the company of friends.

Especially in Figure 3. As shown in the diagram, in the rubber weir,
The upstream side of the rubber weir collapsed due to sediment accumulation.
In this case, during the overturning process of the rubber weir, the rubber weir does not lower uniformly, but drops locally in a part of the river width of the rubber weir (for example, the center force), and a V-notch a occurs. and upstream fu
Most of the flowing water flowing from ll to the downstream side η7 crosses the V-notch a, downstream 1 rule'c rubber on both sides of the V-notch a +1
A whirlpool flow in the direction of arrow C toward the u & lower section is generated, and the sediment in the flowing water containing a large amount of sediment hits the rubber R on both sides of the V nonch a.
It is unavoidable to find a large amount of comrades deposited on the floor directly below.

If the earth and sand accumulates on the downstream side of the undulating weir in this way, even if the undulating weir is laid down as shown by the two-dot chain line in Figure 1 or Figure 2, it will be partially undulated by the accumulated earth and sand. The weir force S does not completely collapse, and the area of the weir is greatly reduced near the undulating weir, significantly impairing its ability to prevent flooding.

A: The invention relates to the invention of an undulating weir using such a sister point σ) A device for preventing sediment deposition, and in an undulating weir installed at the terumasa crossing of Dongyogi, the undulating weir is One end of the piping is opened into the water on the upstream side, and the other end of the piping is opened into the sediment accumulation area on the downstream side of the undulating weir, and its purpose and location are the downstream of the undulating weir. The point is that it provides a device with a simple structure that can reliably prevent dirt from accumulating on the sides.

'
One end of the pipe was opened, and the other end of the pipe σ] was opened into the sediment accumulation area on the downstream side of the undulating weir. , some of the water flows through the pipe from an opening at one end of the pipe j1,
From the opening at the other end of the piping, it is discharged from the sediment accumulation area on the downstream side of the undulating weir, and the water flow removes the sediment that has accumulated or is about to accumulate in the sediment accumulation area.

As a result, in the invention, when the undulating weir is erected, the accumulation of earth and sand in the downstream of the undulating weir is prevented, so the undulating weir can be completely collapsed, thereby preventing flooding. Functionality can be maintained.

An embodiment of the invention shown in FIGS. 4 to 6 will be described below.

The main component of the flexible membrane weir (hereinafter simply referred to as rubber salt) is a belt-shaped rubber sheet, and with its folded side edge positioned on the upstream side, it is constructed using a presser foot 5 and an anchor bolt 6. The flexible bag body is firmly and air-tightly adhered to the top surface 38 of the river bed concrete 2 and the river slope 4.

In addition, a supply/discharge pipe (not shown) is communicated with the inside of the rubber weir 1. By supplying and discharging water or air into the rubber weir 1 through a supply/discharge pipe (not shown) by operating a pump or the like, the rubber salt 1 can be made to undulate.

Roughly, rubber salt 1 (/
] At the time of standing up, a step 3a is formed at a point away from the downstream surface 1a of the rubber salt 1, and on the step 3a, a pipe 7 is laid along the river slope 4 by circulating across the width of the river. After penetrating the river and making a few turns to the upstream side, it made several turns upwards.
Upstream i? tAi7a'G: is opened from the river slope 4 into the river, and the downstream of the same pipe 7 1i1i7b
4: f is blocked.

Therefore, a large number of spouting lowers d are provided in the spouting portion 7c adjacent to the riverbed concrete top surface step 3a of the piping 7, and circulating in the downstream direction of the river at predetermined intervals over the longitudinal direction. Upstream end/open lower a [screen 8 is attached.

Further, since an on-off valve 9 is provided in the piping 7, the on-off valve 9 is not necessarily required.

Embodiment 1+Iff to Embodiment C shown in FIG. It flows into the same pipe 7 from the flow lower a, and flows into the riverbed concrete top surface step 3a [adjacent spouting part 7c Vc
After that, it is discharged from the spout lower d which circulates in the downstream direction of the river. In this case, the flow velocity of the water stream jetting out from the jetting lower d is 0 fish (where C is the velocity coefficient), where h is the difference in the water head between the water surface on the upstream side of the rubber salt 1 and the jetting lower d. Even if the sediment 11 is deposited on the river bed concrete top surface 3 in the sediment accumulation area 1o downstream of the rubber salt 1, the same sediment 11 is
is removed downstream by a restraining force.

Therefore, when the rubber salt 1 is laid down, the downstream surface 1a of the rubber salt 1 should be brought into close contact with the riverbed concrete top surface 3 and the slope 4, as shown by the two-dot chain line in FIG. The ability to prevent flooding by keeping the cross-sectional area of the river approximately constant during high flow rates is remarkable.

'-1' Pipe water intake lower a to rubber period 10] When standing σ)
Since the VC is installed higher than the crest of the dam, when the amount of water exceeds the required amount for irrigation, the excess water can be used to remove the sediment.

Since the on-off valve 91) is interposed in the piping 7, if the concrete top of the cave bed downstream of the rubber ring 1 has accumulated soil 117i, the on-off valve 9 is opened and the soil 117i: &-1 if excluded, deposited and none)
Close the on-off valve 9 and spray water from the pipe 7.
You can do it like that.

In the embodiment shown in FIGS. 4 and 5, most of the piping 70 is laid at approximately the same height as the river bed concrete top surface 3,
G) Loca, 61st PX, looking upward only at the upstream end
As shown in Figure J, the piping 12 is bent into an inverted U-shape, and the upstream end opening 12a of the piping 12σ) is placed at a position lower than the top of the weir of the rubber ring 1 in the upright state, and the top 12b of the piping 12 is bent. It may be arranged at a position lower than the top of the weir, and in such an embodiment, when the water level on the upstream side of the rubber ring 1 reaches the water level at which the rubber ring 1 in the upright state must be laid down, the piping 12 is Start spouting water from spout 12c,
In addition, as shown in Figures 7 and 8, the inverted U-shaped piping 13 is buried only within the river slope 4. , the water intake opening 13a of the same piping 13 is placed in the upright state σ] rubber weir 1σ) lower than the weir top, and the middle part 1
3b is placed at a position higher than the top of the weir, and the spouting hole t3ce of the same pipe 13 opens onto the river slope 4 at a position slightly higher than the concrete top surface 3 of the cave floor, and is located downstream from the rubber ring 1. At the top of the cleat ■3, the spout part of the piping 3 is 1.30
An earth and sand discharge horizontal groove 14 may be provided at a point corresponding to the installation position of the pipe 13, and several earth and sand discharge vertical grooves 15 may be provided downstream of the horizontal groove 14. By forcefully spouting water from the spout 13C into the earth and sand discharge horizontal groove 14, the earth and sand 11 can be easily removed.

A pump may be installed in the piping 7.12.13 of the above embodiment, and in such an embodiment, water can be discharged at a flow rate higher than the flow rate determined by the water head difference, and sediment removal can be carried out more reliably. Gisekotoh) Desaro.

In the above embodiments, the present invention has been applied to the rubber ring, but the present invention can of course also be applied to a steel overturning gate salt as shown in No. 21=21.

[Brief explanation of drawings]

Figure 1 is an explanatory side view showing the state in which earth and sand have accumulated on the downstream side of a rubber ring, which is a type of undulating weir, and Figure 21 shows the state in which earth and sand have accumulated on the downstream side of a steel overturning gate salt. In the illustrated explanatory side view, 3rd M shows a state in which soil cannot be removed in the event that a notch occurs, even if the rubber ring is collapsed.
- Explanation) 111 and 1, Fist 4I% is an example of the earth and sand accumulation prevention II of the undulating weir according to the present invention: an embodiment of the device (il - Illustrated cross-sectional side view, top view of the 5th lock main, Fig. 6 is Other Embodiments α) Transverse Side View, No. 71', 4 is a cross-sectional side view of another embodiment, and FIG. 8 is a plan view thereof. 1...': fh weir, 2... riverbed concrete, 3.
... River bed concrete top surface, 4... River slope, 5...
・Presser foot, 6... Anchor bolt, 7... Piping, 8.
... Screen, 9 ... Open calm valve, 10 ... Sediment accumulation area, 11 ... Sediment, 12 ... Piping, 13 ... - Inverted U-shaped pipe, 14 ... Sediment discharge horizontal groove , 15... Sediment discharge vertical groove. Agent: Patent attorney Nozomi Ehara (1 person)

Claims (1)

[Claims] In a undulating weir installed in the direction of a river, one end of the piping is opened into the water at 1111 upstream of the undulating weir, and the other end of the piping is connected to the downstream side of the undulating weir. A device for preventing sediment accumulation using an undulating weir, which is characterized by an opening in the sediment accumulation area.