JPS60152713A - Method of preventing diffusion of contamination at intake and drainage part of dam - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a raising phenomenon of deposit and pollution of effluent from a dam, by a method wherein auxiliary of flaps are attached to a flow excess flap, and a flow switching fence formed with the flaps respectively having a weight at the lower end thereof is disposed around the intake and drainage part of a dam. CONSTITUTION:Auxiliary flaps 2 are attached in arbitrary stage to a netty or card fabric-like flow excess flap 1, and weights 3 are respectively attached to the water flow excess flap 1 and the auxiliary flaps 2 to form a flow direction changing fence. If the flow direction changing fence is located around the intake of a dam, when a water flow flowing in the direction of the intake resulting from discharge passes through the direction changing fence, the water flow is changed downward by exerting resistance of the auxiliar flaps 2 thereon. This enables prevention of production of a raising water flow at the bottom of a dam, prevents the occurrence of a raising phenomenon of deposit on the dam bottom, and permits prevention of contamination of effluent from the dam.

Description

[Detailed Description of the Invention] Conventionally, when collecting (draining) surface water from dams, settling basins, settling basins, reclaimed spillways, etc. (hereinafter referred to as dams, etc.), resurfacing flow occurs near the collecting (draining) xylem. Lifting phenomena such as , density currents, and convection occur, resulting in the entrainment of sediments or sediments at the bottom of the water, resulting in a situation where the quality of surface water deteriorates (see Figure 1). This phenomenon occurs particularly when the amount of collected (drained) water per unit time is large. Until now, no method has been found to effectively prevent these phenomena.

The present inventor has completed various studies to solve these conventional drawbacks, and as a result, has completed the present invention.

That is, the present invention provides an arbitrary number of stages of auxiliary flaps for the water-permeable flap, and a flow-changing fence with a weight provided at the lower end of the water-permeable flap and the auxiliary flap for collecting and discharging trees in a dam, etc. This is a method of preventing pollution from spreading by placing it around the area.

Next, the present invention will be explained with reference to the drawings.

FIG. 2 is a front view of the variable current fence used in the method of the present invention, and FIG. 3 is its (IJI uii 7).

The current-changing fence is a device consisting of a water-permeable flap L, an auxiliary flap 2, and a weight 3.As is clear from FIG. It is set in the state. Although the auxiliary flaps a are shown in FIG. 3 as being provided in two stages, they may be provided in any number of stages depending on the length of the water-permeable flap 1 and the like.

A weight 3 is provided at the lower end of the water-permeable flap 1 and the auxiliary flap 2.

The water-permeable flap 1 may have any shape as long as it allows water to pass through, such as a net shape or a sag shape. Further, the auxiliary flap 2 can be in the form of a sheet, a perforated sheet, a sag, or the like.

Further, as another embodiment of the current diversion fence used in the method of the present invention, an auxiliary flap 3 may be further provided below the water permeability flap 1 as shown in FIG.

For example, if the current diversion fence is installed around the water collection mouth of a dam as shown in Figure 5, when water is released from the water collection mouth, a water flow will be generated toward the water collection mouth, and this water flow will be assisted when passing through the current diversion fence. The current changes downward due to the resistance of 7 laps. The present invention can suppress the generation of upward water flow at the bottom of the dam due to this downward shift, thereby suppressing the lifting up of sediment at the bottom of the dam and preventing pollution of the water discharged from the dam. The effect of this current variable fence will be further improved if multiple fences are used.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional dam, FIG. 2 is a front view of a current shifting fence, FIG. 3 is a side view of FIG. 2, and FIG. 4 is a side view showing another aspect of the current shifting fence. Figure 5 shows a cross-sectional view of a dam equipped with a diversion fence. Engraving of the drawings (no changes to the contents) Figure 1 Sailamatsuwa T Oda prisoner procedure amendment basis (method) % formula % 1. Indication of the incident Patent Application No. 9821 of 1982 2. Name of the invention Collection of dams, etc. Method for Preventing Pollution Diffusion in Drainage Sections 3, Relationship with the Amendment Case Patent Applicant Address: 5th Floor, Ni-Shinbashi Building, 2-16-1 Shinbashi, Minato-ku, Tokyo Name: Nippon Solid Co., Ltd. (Seal changed as of today) ) 5. Specification and drawings to be amended 6. Contents of amendment Based on the April 4, 1980 Procedural Amendment Directive, the application, specification, and drawings will be amended to a printed version. (No change in content)

Claims (1)

[Claims] It is characterized by providing an arbitrary number of stages of auxiliary flaps on the water-permeable flap, and arranging a flow-changing fence with weights provided at the lower ends of the water-permeable flap and the auxiliary flap around a collection and drainage area such as a dam. A method for preventing pollution diffusion in the collection and drainage areas of dams, etc.