JPS6225804B2 - - Google Patents

Description

[Detailed description of the invention] A flexible membrane undulating weir has a flexible membrane envelope (bag-like body) that forms the weir body attached to at least the river bed in the direction across the river, and inside the envelope. A fluid such as air, water, or both is sent from a communicating inlet/exhaust (water) pipe to cause the pipe to expand and stand up, or to discharge fluid to cause the pipe to contract and fall down.
(See Special Publication No. 44-2371).

Conventionally, in this type of undulating weir, when there is 5" of sediment on the downstream side of the weir as shown in Figure 1, for example, when it is installed near the coast for the purpose of tide protection or sand control, the undulating weir is At this time, the downstream portion of the flexible membrane envelope 1'' covers the sediment 5'' as shown in Figure b.
That is, when it is collapsed, the cover acts as a resistance to flowing water, making it impossible to discharge sediment due to upstream water and narrowing the cross section of the river channel.There is a risk that the river will become swamped when water comes out, making it impossible for the river water to flow down safely.

In FIG. 1, 2'' is an expansion medium such as air or water, 3'' is upstream water, 4'' is a river bed, and 6'' is an inlet/outlet (water) pipe.

The present invention has been made to solve the above problems. A detailed explanation will be given below with reference to the illustrated drawings.

FIG. 2 shows the undulating weir of the present invention, in which reference numerals 1 and 1' denote a flexible membrane envelope forming the external weir body, and an internal flexible membrane envelope used during sand removal;
2 and 2' are pressure medium fluids, such as air or water, or both, sent into 1 and 1', respectively; 6 and 6' are fluids 2 and 2' sent into envelopes 1 and 1'; and exhaust (water) discharged from 1'
3 is the upstream water, 4 is the river bed, 5 is sediment, 7 and 7' are the upstream attachment parts of the river bed of the envelopes 1 and 1', and 8 and 8' are the riverbed parts of the envelopes 1 and 1'. This is the attachment part on the downstream side of the river bed.

Further, the flexible membrane is, for example, rubberized cloth,
The height (or diameter) of envelope 1' when it expands and stands up is
and the circumference in the flow direction of the envelope 1, that is, the length from the upstream attachment part of the river bed to the downstream attachment part of the river bed (the length from 7 to 8 in Figure 2). ) is the circumference of the envelope 1' in the machine direction (the second
It is shorter than the sum of the length from 7' to 8' in the figure) plus the length from 8' to 8 in Figure 2.

The present invention is constructed as follows.

(a) The expansion and erection of the weir is done as follows.

The external flexible membrane envelope 1 forming the weir body is expanded and erected by an expansion medium 2 through an inlet/exhaust (water) pipe 6. At this time, the inner flexible membrane envelope 1' is in a contracted state (see FIG. 2a).

(b) The contraction and lodging of the weir is carried out as follows.

When the upstream water level 3 reaches the planned collapse water level, the internal flexible membrane envelope 1' is expanded by the expansion medium 2' through the inlet/exhaust (water) pipe 6', and at the same time as the expansion starts, the external flexible membrane envelope 1' is expanded. Inject and exhaust the expansion medium 2 in the target 1 (water)
Exhaust (water) through pipe 6 (see Figure 2b).

The inner flexible membrane envelope 1' expands and stands up under a predetermined internal pressure, and the outer flexible membrane envelope 1 bulges against the inner flexible membrane envelope 1 as shown in FIG. 2b. When the weir contacts the outer periphery of the weir, the expansion medium 2' in the internal flexible membrane envelope 1' is exhausted (water) through the inlet/exhaust (water) pipe 6', and the contraction and lodging of the weir is completed. do.

In the present invention as described above, when the weir contracts and collapses, the external flexible membrane envelope 1 forming the weir body
The circumference in the flow direction of the inner flexible membrane envelope 1'
From the circumference in the flow direction plus the length from the downstream attachment point of the flexible membrane envelope 1' on the river bed to the downstream attachment section of the riverbed of the flexible membrane envelope 1. Since it is made short, the external flexible membrane envelope 1 does not protrude downstream from the downstream side attachment part 8 of the river bed.
It is completely housed between the river bed upstream mounting section 7 and the river bed downstream mounting section 8.

Therefore, even if there is sediment on the downstream side when the weir body expands and stands up, when it collapses, the downstream part of the envelope that forms the weir body does not cover the sediment, and the sediment is discharged by the outflow force of upstream water. I can do it. Therefore, the cross section of the river channel is not obstructed, and the river water does not flood during floods, allowing the river water to flow down safely.

[Brief explanation of the drawing]

FIG. 1 is a view of a conventional undulating weir made of a flexible membrane taken along the river flow direction, where FIG. a shows the undulating weir when it is inflated, and FIG. Figure 2 is a view of the flexible membrane undulating weir of the present invention taken along the river flow direction; Figure a shows the weir when it is fully expanded and erected, and Figure b shows the weir body between the time when the weir expands and erects until it contracts and collapses. Figure c illustrates the state in which the external envelope is contracted during formation, the internal envelope is expanded during sand removal, and the weir is fully contracted and collapsed. 1... Flexible membrane casing forming the external weir body, 1'... Flexible membrane casing used for internal sand removal, 2, 2'... Expansion medium, 3... Top running water, 4
... River bed, 5 ... Sediment, 6, 6' ... Inlet/exhaust (water) pipe, 7 ... Water intake part on the upstream side of the river bed of envelope 1,
7'... Water intake part on the upstream side of the river bed of the cover 2, 8... Water intake part on the downstream side of the river bed of the cover 1, 8'... Water intake part on the downstream side of the river bed of the cover 2.

Claims (1)

[Claims] 1. In a weir in which a flexible membrane envelope is attached to at least a river bed in a direction across the river, fluid is sent inside the envelope to cause it to expand and erect, and fluid is discharged from the interior of the envelope to cause the weir to contract and fall down. The height (or diameter) when the body is inflated and erected inside the outer envelope that forms the main body.
a flexible membrane envelope smaller than that of the outer envelope, and of a size such that, when contracted and collapsed, the downstream end of the envelope is located upstream of the attachment line on the downstream side of the riverbed of the outer envelope; The outer sheath and the inner sheath are installed at least in the direction across the river, and the outer sheath and the inner sheath are made to expand and erect and contract and fall down independently, and the circumference of the outer sheath in the flow direction is the same as that of the inner sheath. It is at least shorter than the circumference in the flow direction of the weir plus the distance from the downstream attachment line of the river bed of the inner sheath to the downstream attachment line of the river bed of the outer sheath, and When raising the weir, fluid is sent to the outer sheath to inflate it, and when the weir is toppled, fluid is sent to the inner sheath to expand it, and at the same time, the fluid inside the outer sheath is discharged so that the inner sheath is completely expands,
When the outer sheath comes into contact with the outer circumferential surface of the inner sheath, the fluid inside the inner sheath is also discharged and contracted, and when the weir collapses, the downstream collapsed end of the outer sheath touches the outer sheath. An undulating weir made of a flexible membrane, characterized in that it does not protrude downstream from an installation line in a direction that crosses a river on the downstream side.