JPH09151444A - Installation structure for bag type weir - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily control irrigation in a basin both upstream and downstream of bag type weir. SOLUTION: A circular arc fastener 4 is provided on a river bed in such a state as projected toward an upstream side and the joint part 3a of a bag type weir body formed out of a twofold flexible membrane 2 is kept in close contact with and fixed to the fastener 4. As a result, the top of the weir body is curved and a stream running over a weir body top increases and vibration resistance is improved. Thus, a flowrate normally running over the weir body top increases to become advantageous for a downstream basin. At the same time, the collapsing frequency of the bag type weir due to a water level fluctuation is reduced to become advantageous for an upstream basin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bag-like weir installation structure that is provided across a river to control the upstream and downstream water levels.

[0002]

2. Description of the Related Art A bag-like weir provided across a river is made of a rubberized cloth (flexible membrane), and normally the weir body is arranged in a straight line in a direction orthogonal to a water channel. When storing water, the bag-like weir is raised, and when the upstream water level rises, the bag-like weir is laid down to allow excess water to flow down. The bag-like weir has a mechanism in which a fluid is put into the bag to expand and weir it, and when the bag is toppled, the fluid is discharged. When the bag-like weir is weired and the stored water increases, vibration of the water surface that generates a force in the upstream and downstream directions of the water flow causes a large load on the weir body. In the method of filling air, the rate of expansion and contraction of air is larger than that of water, and it is easily affected by external factors such as vibration of the water surface. Therefore, the overflow water depth is set to rise or fall within a range not exceeding 20% of the weir height.

[0003]

However, because of the above conditions, the overflow water depth is kept at a small level at all times because the maximum overflow water depth of the stored water is laid down so that the overflow water depth does not reach the upper limit. In addition, since the lodging frequency is high, running water cannot be stored for a long period of time. Therefore, it may be overlaid even when water is needed to store water, and it is inconvenient to manage water use and water level upstream. In addition, since the overflow water depth is kept small, the normal total overflow is reduced, but there are many lodging operations and the water level changes in the downstream region are severe, which makes management difficult.

It is an object of the present invention to provide a bag-like weir installation structure in which the load on the weir body is suppressed and the overflow amount is increased.

[0005]

In order to achieve the above-mentioned object, the present invention arranges a stopper in an arc shape so as to project upstream in the river bed and fold the flexible membrane in two to bring the mating portion into close contact. The bag-shaped weir body is fixed by the stopper.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The bag-like weir targeted by the present invention is made of rubberized cloth, and when the overflow water depth increases, the vibration of water in the upstream and downstream directions greatly affects the weir body. Especially when air is added. Therefore, it is necessary to strictly observe the upper limit of overflow water depth. On the other hand, increasing the amount of overflow due to water utilization in the downstream area is convenient for management.
In view of this, conventionally, the weir was laid down by a slight change in the water level, but in the present invention, the shape of the weir body is formed in an arc shape in the flow direction to increase the overflow length. Also, due to this shape,
The external force due to the vibration in the water flow direction is dispersed in the water channel width direction, the rigidity strength is increased against external factors, the allowable value of the overflow water depth is sufficiently maintained, and the total overflow flow increases. In addition, since the fluctuation of the water level becomes gentle, the number of lodgings is reduced.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings. As shown in Fig. 1 and Fig. 2, seawalls 2 are constructed on both sides of the waterway 1, and the slope of the seawall 2 and the riverbed (width W)
The stoppers 4 of the bag-shaped weir 3 are arranged in a convex arc shape on the upstream side, and the stopper 4 is brought into close contact with the mating portion 3a of the bag-shaped weir 3 obtained by folding the rubberized cloth in two. Fixed on the riverbed. Both ends of the rubber-folded cloth folded in two are closely fixed by a stopper 4 arranged on the revetment 2 to form a bag, and the bag-like weir 3
Is designed to inflate the fluid inside.

The fluid to be put into the weir body is generally water or air. As an example, as shown in FIG. 3, by connecting a blower / exhaust pipe 6 from a blower 5 to the inside of the bag-like weir 3, air is discharged. Is supplied to expand and weir it. Since the top of the weir body is formed in an arc shape having substantially the same height by the air supplied into the weir body made of rubberized cloth, the overflow water depth H is substantially the same at any position with respect to the water flow. Therefore, the top of the weir body becomes longer than the weir that was conventionally provided in a straight line,
Since the weir body is curved at the time of standing, the external force due to the vibration in the water flow direction is dispersed in the waterway width direction, the load on the weir body is reduced, and the overall flow rate is increased compared to the linear weir. . As a result, fluctuations in the overflow water depth H are reduced, and it is possible to easily manage the upstream and downstream water levels. Also,
By making the weir body into an arc shape, it is possible to create a landscape that is in harmony with the surrounding environment by imagining a waterfall in the natural world, away from the image of a conventional weir.

[0009]

EFFECTS OF THE INVENTION Since the present invention is configured as described above, water flows down from the curved top of the weir body, and the total overflow rate can be increased even when the overflow depth is low. Since the fluctuation of overflow water depth also becomes small, the maximum water level of stored water rarely approaches the upper limit of overflow water depth under the baggage weir collapse condition, which facilitates the management of upstream and downstream water levels.

[Brief description of the drawings]

FIG. 1 is a plan view showing an installation structure of a bag-like weir having a cross section showing that a revetment is inclined in the lower part, according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the water channel of the bag-like weir shown in FIG. 1 viewed from the downstream side.

FIG. 3 is a side sectional view of the bag-like weir shown in FIG.

[Explanation of symbols]

 3 bag-like weir 3a mating part 4 stopper

Claims (1)

[Claims] 1. A stopper is arranged in an arc shape so as to project upstream from the river bed, and the flexible membrane is folded in two to bring the joints into close contact with each other. A bag-like weir installation structure characterized by being fixed by a tool.