JPH01142114A - Method and apparatus for discharging deposit sand in dan - Google Patents

Abstract

PURPOSE:To exactly discharge soil by a comparatively simple constitution in which the sand discharge tube of dam is connected with a soil excavating and stirring device by a pipeline, and soil is discharged by utilizing a head difference between the water surface and the sand discharge tube. CONSTITUTION:A sand discharge tube 12 is set on the lower part of a dam 10 and connected through a connector 14 set inside to a pipeline 16 the suction port of which is connected with a soil excavating and stirring device 18. The device 18 is supported in a rocking manner through a strut 30 from a base ship 20 floating in the dam 10 and vertically moved to any desired position as the ship 29 moves. Soil coming into the pipeline 16 through the device 18 can be discharged from a soil discharge tube 18 by head difference produced between water surface 26 and the tube 12 without resorting to specific drive force.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method and apparatus for removing sediment from a dam.

(Conventional technology) Dam storage lakes are destined to suffer from sedimentation, but recently, various problems such as deterioration of dam function, occurrence of flood damage, and water intake problems due to the progress of sedimentation have been addressed. Therefore, dam refreshment, which involves removing sediment and taking permanent measures to remove sediment, has become important in dams where sedimentation is particularly significant.

Recently, the amount of inflowing sediment has been decreasing due to the planting of surrounding slopes and the construction of sand control dams, but it is still far from zero, and a permanent countermeasure against inflowing sediment is desired.

Conventionally, many methods of removing sediment flowing into a dam storage lake to the downstream side of the dam body include installing a sand removal tunnel or pipe in the dam and utilizing the sweeping force of water. .

However, with these sand removal equipment, there is a risk that obstacles such as gravel or sunken trees may get into the sand removal tunnel, sand removal pipe, etc., and the gates of the sand removal tunnel, sand removal pipe, etc. may not close when you want to close them. The reality is that the suction port is in a fixed location and has to wait for sediment to flow in, making it unable to perform its function effectively.

For these reasons, various methods and devices for removing sand from dams have been proposed, and they can be roughly divided into those that use sand removal tunnels and pipes installed in dams, and those that use sand removal tunnels and pipes installed in dams; There are some that do not use established sand removal tunnels or sand removal pipes.

The former configuration generally involves laying a pipeline from the sand discharge pipe inside the dam body, and the pipeline inlet is placed in a sand stopper dam upstream of the dam, or inside the dam body. There is. Such a configuration is disclosed in, for example, Japanese Patent Publication No. 53-25420, Japanese Patent Publication No. 53-25421, Japanese Patent Publication No. 58-49646, and Japanese Patent Application Laid-Open No. 55-3.
It is disclosed in Japanese Utility Model Publication No. 6556, Japanese Utility Model Application Publication No. 58-156729, etc. The latter configuration generally involves dredging the inside of a dam's storage lake, sucking up the dredged earth and releasing it downstream of the dam body through a pipeline, and some use the siphon principle in doing so. be.

Such a configuration is disclosed in, for example, Japanese Patent Publication No. 52-38340, Japanese Patent Publication No. 56-12655, and Japanese Patent Application Laid-Open No. 54-14.
It is disclosed in Japanese Patent Application Laid-open No. 2837, Japanese Patent Application Laid-Open No. 56-93914, Japanese Patent Application Laid-open No. 108410-1987, and the like.

(Problems to be Solved by the Invention) However, in the case of the former configuration, the pipeline and its suction port are fixed, and there is a drawback that sediment accumulated at a location away from the suction port cannot be removed. Also,
In the case of the latter configuration, equipment such as a suction pump (drainage pump, water injection pump) is required in addition to the earth and sand excavation and agitation device that stirs the earth and sand, and even when using the siphon principle, a pump must be used at startup. However, the structure is expensive and complicated.

Therefore, an object of the present invention is to provide a dam sediment discharge method and a sediment discharge device that have a relatively simple configuration, can reliably discharge soil, and can effectively utilize the existing dam body discharge pipe. It's about doing.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention movably arranges a sand excavation and agitation device in the water of a dam reservoir, and connects the sand discharge pipe of the dam body and the sand excavation. Connect the stirring device with a pipeline,
When the earth and sand excavation and agitation device is activated, the earth and sand flowing into the earth and sand excavation and agitation device are drained by flowing through the pipeline and the sand removal pipe using the water head difference between the sand discharge pipe of the dam body and the water surface of the reservoir lake. A method for discharging dam sediment characterized by sanding,
and a sand excavation and agitation device movably disposed in the water of a dam reservoir, and a pipeline connecting the earth and sand excavation and agitation device to a sand discharge pipe of a dam body. It uses a sand device.

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

FIG. 1 is a schematic explanatory diagram of a sand removal device of the present invention.

FIG. 2 is a side view showing an example of a cutter of the earth and sand excavation and agitation device used in the sand removal device of the present invention.

FIG. 3 is a side view of the pipeline of the sand removal device of the present invention.

In FIG. 1, a sand discharge pipe (or sand discharge tunnel) 12 is provided at the bottom of a dam body 10, and its gate (not shown) is normally closed.

The sand discharge pipe 12 may be an existing one or a new one provided for carrying out the present invention.

A pipeline 16 is connected to the sand discharge pipe 12 via a connection part 14 installed on the inside (upstream side) thereof, and a sand excavation and agitation device 18 is connected to the suction port side of the pipeline 16. There is. Although any suitable device such as a cutter, a jet excavation and agitation device, etc. can be used as the earth and sand excavation and agitation device, the following explanation will be based on a case where a cutter is used as an example. An earth and sand excavation stirring device, for example, a cutter 18, is swingably supported from a barge 20 floating within the dam body via, for example, a support 30.

With this structure, the cutter 18 can be moved to any desired position as the barge 20 moves, and can also be moved up and down at that position. In addition,
Reference numbers 22, 24, and 26 indicate the original river bed surface, sediment surface, and water surface, respectively. Furthermore, due to the head difference created between the water surface 26 and the sand discharge pipe 12, the sediment flowing into the pipeline 16 through the cutter 18 below the water surface 26 does not require any special driving force. It is configured to flow through the pipeline 16 and be discharged from the sand discharge pipe 12.

Next, the cutter 18 will be explained with reference to FIG. A main body 18a of the cutter 18 is supported by a column 30, and a rotary shaft 32 is rotatably supported at the tip of the main body 18a. The rotating shaft 320 rotations can be achieved by, for example, a thrust bearing (not shown) with power distributed directly above the support column 30, and a hydraulic motor (not shown) connected via a coupling (not shown).
given by. A plurality of cutter blades are attached to the outer periphery of the rotating shaft 32 as in the conventional case, and when the rotating shaft 32 is rotated, the cutter blades 3 and 4 stir the soil and facilitate suction from the sand discharge pipe. let

A suction port 36 is provided on the side of the main body 18a, and a connecting pipe 38 having a flange 40 at the end is connected to the suction port 36.
is installed. The pipeline 16 is connected to the connecting pipe 38 by a flange 42.

- Next, the pipeline 16 will be explained with reference to FIG. The pipeline 16 includes a plurality of iron pipes 50, a flexible rubber sleeve 52, for example, which connects these iron pipes 50,
It consists of a floating body 54 attached to the outside of an iron pipe 50, and is constructed so that the overall specific gravity of the pipeline 16 is about 1. Therefore, the pipeline 16 can float in water or float on water. However, to limit floating of the pipeline 16, the pipeline 16 may be moored to the sediment surface 24 by a mooring device 56, as shown in FIG.

Next, an example of the working process of the sand sedimentation method of the present invention will be explained.

A pipeline 16 is connected to the sand discharge pipe 12 of the dam body 10, and a cutter 18 is further connected to the suction port of the pipeline 16. On the right, when the pipeline 16 is installed in a state where it is connected to the sand discharge pipe 12, the cutter 18 is simply connected to the pipeline 16. The gate of the sand discharge pipe 12 is opened and the cutter 18 is driven. Therefore, the earth and sand are stirred by the cutter 18, and the earth and sand is sucked into the pipeline 16 due to the water head difference, passes through the pipeline 16, and is discharged from the sand discharge pipe 12. Then, the barge 20 is moved to remove sand from a desired area. Next, the cutter 18 is lifted away from the earth and sand, and only water is allowed to flow through the pipeline, thereby discharging any earth and sand that may have accumulated in the sand discharge pipe. By discharging the earth and sand in this manner, there is no earth and sand in the sand discharge pipe when the gate is closed, and the gate can be closed without any obstruction.

(Effects of the Invention) As is clear from the configuration described in detail above, the present invention has the following effects.

(1) When you want to close the gate after flushing away the earth and sand, lift the cutter and place the pipeline inlet in the water. Only water will flow and be removed, so the gate will close better than the obstruction. It will never go away. The gate can be opened and closed at any time as needed.

(2) Since the pipeline suction port can move together with the cutter, it can actively suck in dirt and discharge sand with high efficiency.

(3) Along with sand removal, drain the water in the bottom layer, which may turn into so-called "dead water" and cause water quality problems such as oxygen deficiency.
Can be replaced with water in the upper layer.

(4) Since the water head difference is used as the energy for flowing water, there is no need for any power to remove sand over the dam body, making it economical.

(5) It can also be used as a countermeasure for various problems occurring in downstream areas of rivers due to the flow of earth and sand (for example, lowering of the river bed, erosion of bank walls, etc.). −

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of a sand removal device of the present invention. FIG. 2 is a side view showing an example of a cutter of the earth and sand excavation and agitation device used in the sand removal device of the present invention. FIG. 3 is a side view of the pipeline of the sand removal device of the present invention. 10...Dam body, 12...Sand discharge pipe, 16...Pipeline, 18...Cutter, 20...Barge . Figure 1 ” +2 Figure 3

Claims (8)

[Claims] (1) Sediment excavation and agitation equipment is movably placed in the water of the dam reservoir, the sand discharge pipe of the dam body is connected to the earth and sand excavation and agitation equipment via a pipeline, and the earth and sand excavation and agitation equipment is operated to excavate the earth. A dam sediment discharge system characterized in that sediment flowing into an agitation device is discharged by flowing through a pipeline and a sediment discharge pipe using the water head difference between a sand discharge pipe of a dam body and the water surface of a reservoir lake. sand method. (2) The method for removing sediment from a dam according to claim 1, characterized in that only water is allowed to flow through the pipeline and the sand removal pipe before the sand removal pipe is closed. (3) The method for discharging dam sediment according to claim 1, wherein the earth and sand excavation and agitation device is supported by a barge. (4) The method for discharging dam sediment according to claim 1, wherein the pipeline is configured to be floatingly moored in and on water. (5) A dam sedimentation system characterized by having an earth and sand excavation and agitation device movably arranged in the water of a dam reservoir, and a pipeline that connects the earth and sand excavation and agitation device and a sand discharge pipe of a dam body. sand removal equipment. (6) The dam sediment discharge device according to claim 5, wherein the earth excavation and stirring device is supported by a barge. (7) The dam sediment discharge device according to claim 6, wherein the pipeline is configured to be floatingly moored in and on water. (8) The dam according to claim 7, wherein the pipeline has a plurality of iron pipes, a flexible sleeve connecting each iron pipe, and a floating body attached to the outside of the iron pipes. Sediment removal equipment.