JP5466977B2 - Deposition prevention structure and accumulation prevention system and method - Google Patents

Description

  The present invention relates to a deposition prevention structure and a deposition prevention system and method for preventing sedimentation such as sand in a reservoir.

  The effective amount of water storage will decrease as the reservoir deposits progress in the dam. For this reason, it is necessary to eliminate the sedimentation of the reservoir in order to ensure effective water storage capacity and to perform the necessary functions as a stable water use dam / multipurpose dam. As such a dam sand discharging device, a sand discharging device using a hydraulic suction pipe has been developed. In the case of a fixed hydraulic suction type sand discharge device, it is necessary to collect earth and sand at the installation position of the device and perform suction sand discharge.

  Patent Document 1 discloses a configuration in which suction ports are opened at appropriate intervals along the axial direction on the outer surface of the transport pipe, and an opening / closing device that opens and closes the suction ports is installed in each suction port. Disclosed is an apparatus for sucking and transporting underwater deposits that can be efficiently transported over a wide area and used in a large-scale storage facility.

JP 2005-2609 A

  According to the conventional sand discharging apparatus as described above, it is necessary to efficiently accumulate earth and sand on the hydraulic suction type sand discharging pipe. Further, in the case of a fixed hydraulic suction type sand discharge device such as Patent Document 1, it is necessary to accumulate earth and sand on the sand discharge pipe, but this is not a mechanism for controlling the accumulation location.

  Further, when the sand removal device is exposed in water, fluid force may act on the device due to the flow, which may cause problems in stability and safety. Moreover, since the suction area of the hydraulic suction type sand discharge device is limited, a large amount of earth and sand cannot be discharged if there are few installation places.

  In view of the problems of the prior art as described above, the present invention efficiently accumulates underwater sediment such as sand in the upstream portion of the sedimentation area of a reservoir such as a dam and discharges the accumulated sediment. An object of the present invention is to provide a deposition prevention structure and a deposition prevention system / method capable of effectively preventing accumulation of underwater sediment in a sedimentation area of a reservoir.

Deposit prevention structure for achieving the above object, the water near the O urchin seabed against positive flow of water in the upstream portion of the sedimentation zone to prevent deposition of water sediments in sedimentation zone of Reservoir A deposit prevention structure characterized in that a plurality of bumps made of a concrete structure are installed so as not to obstruct the flow of water, and underwater deposits are deposited near the bottom of the bumps .
It is characterized by being configured.

According to this accumulation prevention structure, the water flow strikes a plurality of solid bodies extending from the bottom of the water to the vicinity of the water surface so as to face the flow of water and not to disturb the flow of water. A vortex is generated from the area, and this vortex causes Ekman convergence near the bottom shoulder and deposits such as sand. In addition, the flow is stagnant behind the impingement and a calm area is created to promote sedimentation of suspended sediments such as sand. In this way, sediment such as sand is efficiently accumulated upstream of the sedimentation area of the reservoir, and the accumulated sediment is discharged to effectively deposit the sediment in the reservoir. Can be prevented.

In the deposit prevention structure, a plurality of the three-dimensional solids are installed so as not to obstruct the flow of water. 1 to 3 times or more of D (with respect to the water flow direction) is preferable, and the distance between the bumps in the vertical direction parallel to the water flow of each bump is expressed by the width D of the bump (with respect to the water flow direction). 5 to 10 times or more.

  In addition, it is preferable that the said solid body has a shape which does not inhibit the flow of water. The impact solid body can be composed of a flat plate, but may be provided with a guide function for guiding and guiding water so as not to disturb the flow of water.

  Moreover, since the discharge means for discharging the underwater deposit deposited near the bottom of the impact solid can be installed, the underwater deposit deposited near the bottom of the impact solid can be discharged by the discharge means.

  A deposition prevention system for achieving the above object includes the above-described deposition prevention structure, and discharge means for discharging the underwater deposits deposited near the bottom of the collision prevention structure. Features.

  According to this deposit prevention system, deposits can be accumulated near the bottom of the solid body by the deposit prevention structure, and the accumulated deposits can be discharged by the discharge means. In this way, sediment such as sand is efficiently accumulated upstream of the sedimentation area of the reservoir, and the accumulated sediment is discharged to effectively deposit the sediment in the reservoir. Can be prevented.

  A deposition preventing method for achieving the above object is characterized by using the above-described deposition preventing structure and discharging underwater deposits deposited in the vicinity of the bottom of the impact structure.

  According to this deposit prevention method, deposits can be accumulated in the vicinity of the bottom of the solid body by the deposit preventing structure, and the accumulated deposits can be discharged. In this way, sediment such as sand is efficiently accumulated upstream of the sedimentation area of the reservoir, and the accumulated sediment is discharged to effectively deposit the sediment in the reservoir. Can be prevented.

  According to the deposit prevention structure and deposit prevention system / method of the present invention, sediments such as sand are efficiently accumulated in the upstream portion of the sedimentation area of a reservoir such as a dam, and the accumulated deposits are discharged. This effectively prevents the accumulation of underwater sediments in the sedimentation area of the reservoir.

It is a figure which shows roughly the deposition prevention structure installed in the reservoir of a dam by this embodiment. FIG. 2 is a perspective view for illustrating the accumulation of sediment in the vicinity of the bottom of the collision solid as well as the collision solid of the accumulation preventing structure of FIG. 1. It is a perspective view which shows the discharge means of the deposit arrange | positioned at the impact solid of FIG. It is a perspective view for demonstrating the groove | channel which arises when the deposit accumulated near the bottom part of the impact solid as shown in FIG. 3 is discharged | emitted. It is a perspective view which shows another structural example (a)-(d) of the impact solid 11 of FIGS. It is a top view which shows the example of plane arrangement | positioning (a)-(c) which has arrange | positioned two or more impact solids of FIGS. 2-4 in order to comprise the deposition prevention structure of FIG. It is a top view for demonstrating the preferable horizontal direction distance and vertical direction distance between collision solids in the planar arrangement | positioning of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a diagram schematically showing an accumulation preventing structure installed in a reservoir of a dam according to the present embodiment. FIG. 2 is a perspective view for illustrating the accumulation of sediment in the vicinity of the bottom of the collision solid and showing the collision solid of the accumulation preventing structure of FIG. FIG. 3 is a perspective view showing the deposit discharging means arranged in the three-dimensional structure of FIGS. FIG. 4 is a perspective view for explaining a groove formed when the deposit accumulated near the bottom of the solid body is discharged as shown in FIG.

  As shown in FIG. 1, the accumulation prevention structure 10 according to the present embodiment is configured by a solid body 11 installed in the upstream portion of the sedimentation area 3 of the reservoir 2 of the dam 1. As shown in FIGS. 1 and 2, the impact solid 11 is installed so as to stand upright from the water bottom G, and the upper end appears from the water surface S. The collision solid 11 has a predetermined width with respect to the flow of water, faces the flow direction A of water flowing from the upstream, and does not inhibit the flow of water. The impact solid 11 can be installed, for example, as a single plate from a concrete structure, and is constructed to be stable against the flow of water.

  With reference to FIG. 2, the operation of the bumps 11 of the deposition preventing structure 10 will be described. As shown in FIG. 2, since the impact solid 11 faces the water flow direction A, the water flowing from the direction A hits the impact solid 11, so that the water flows around the end 11 a in the direction B. Thus, a vortex swirling in the direction C from the end portion 11a is generated. Due to this vortex, Ekman convergence occurs near the bottom shoulder and the water flow converges, so that a deposit H such as sand accumulates near the bottom of the impact solid 11. Furthermore, on the back surface 11b of the partition plate 11, the flow is stagnated by the partition plate 11, and a calm area is created to promote the sedimentation of suspended sand and the like.

  In the above-described manner, by installing the impact solid 11 constituting the accumulation prevention structure 10 so as to face the water flow direction A, the sediments such as sand are deposited in the upstream portion of the sedimentation area 3 of the reservoir 2. Objects can be efficiently accumulated near the bottom of the bump 11.

  The deposition preventing system according to the present embodiment will be described with reference to FIG. As shown in FIG. 3, the accumulation prevention system 20 includes an accumulation prevention structure 10 including the partition 11 of FIGS. 1 and 2, and a plurality of suction ports installed at the bottom of the partition plate 11 on the back surface 11 b side. A certain suction portion 21, a pipe 22 extending from the suction portion 21 in a substantially vertical direction on the back surface 11b side of the partition plate 11 and then bent and extending to the land side; a suction pump 24 connected to the pipe 22 via a valve 23; Is provided. Further, in order to support the pipe 22 and the like on the back surface 11b side of the partition plate 11, for example, a semi-ring-shaped pipe support portion 25 is preferably provided.

  According to the accumulation prevention system 20 of FIG. 3, by operating the suction pump 24, the sediment H such as sand accumulated near the bottom of the impact solid 11 is sucked from the suction port of the suction portion 21 through the pipe 22. , Can be discharged to the land side.

  As described above, sand or the like is deposited on the bottom of the rear surface 11b of the impact solid 11 by installing the accumulation preventing structure 10 composed of the impact solid 11 in the upstream portion of the sedimentation area 3 of the reservoir 2 of the dam 1. The material H can be efficiently accumulated, and by operating the suction pump 24, the sediment H can be sucked from the suction portion 21 installed at the bottom of the rear surface 11b of the impact solid 11 and discharged to the land side. Thereby, accumulation of underwater sediment in the sedimentation area 3 of the reservoir can be effectively prevented.

  Further, as shown in FIG. 4, a groove I is formed by sucking the deposit H deposited near the bottom of the back surface 11 b of the impact solid 11. Deposition is further promoted, and therefore, the sediment prevention system 20 can increase the discharge efficiency of the underwater sediment by efficiently accumulating the sediment.

  In addition, since a quiet area is secured on the back surface 11b of the impact solid 11, the fluid force acting on the suction portion 21 and the pipe 22 of the deposition prevention system 20 laid on the back surface 11b can be reduced. For this reason, the stability and safety of the accumulation prevention system 20 at the time of a flood etc. can be improved by the impact solid 11.

  FIG. 5 is a perspective view showing another configuration example (a) to (d) of the impact solid 11 shown in FIGS. 2 to 4 are composed of a single plate-like body, they may have the following shapes.

  5A is composed of two plate-like bodies 12a and 12b connected in an L shape, and the water flows from the flow direction A to the top portion 12c where the plate-like bodies 12a and 12b are joined. Hits and flows to the plate-like bodies 12a and 12b on both sides, so that the flow of water is not hindered. At this time, the plate-like bodies 12a and 12b exhibit a guide function for guiding and guiding the flow of water.

  5 (b) has a U-shaped planar shape and is composed of three plate-like bodies 13a, 13b, 13c connected in a U-shape, and flows in the central plate-like body 13b in the flow direction. Since water hits from A and flows to the plate-like bodies 13a and 13c on both sides thereof, the flow of water is not obstructed. At this time, the plate-like bodies 13a and 13c on both sides exhibit a guide function for guiding and guiding water without hindering the flow of water.

  5 (c) has a planar shape of a semicircle, a semi-ellipse, or a semi-elliptical shape, and water hits the central portion 14b from the flow direction A to the curved portions 14a and 14c on both sides thereof. It does not obstruct the flow of water because it flows. At this time, the curved portions 13a and 13c on both sides exhibit a guide function for guiding and guiding water without hindering the flow of water.

  The collision solid 15 in FIG. 5 (d) is composed of three plate-like bodies 15a, 15b, 15c, and water hits the central plate-like body 15b from the flow direction A and spreads on both sides of the plate-like body 15b. Since it flows to the plate-like bodies 15a and 15c connected to, the flow of water is not hindered. At this time, the plate-like bodies 15a and 15c on both sides exhibit a guide function for guiding and guiding water without hindering the flow of water.

  FIG. 6 is a plan view showing planar arrangement examples (a) to (c) in which a plurality of bumps shown in FIGS. 1 to 4 are arranged to constitute the accumulation preventing structure of FIG. FIG. 7 is a plan view for explaining a preferable lateral distance and longitudinal distance between the three-dimensional objects in the planar arrangement of FIG.

  1 to 4 is preferably installed in the upstream part of the sedimentation area 3 of the reservoir 2 of the dam 1 of FIG. An example of the planar arrangement of the deposition preventing structure 10 by the plurality of bumps 11 will be described with reference to FIGS.

  The planar arrangement of FIG. 6A arranges a plurality of bumps 11 at equal intervals in a lateral direction X orthogonal to the water flow direction A and a vertical direction Y parallel to the water flow direction A. It is a thing. Such a planar arrangement does not hinder the flow of water as a whole.

  In the planar arrangement of FIG. 6B, a plurality of bumps 11 are alternately shifted in the horizontal direction X and arranged in a staggered manner, and are arranged in the vertical direction Y at equal intervals. Such a planar arrangement does not hinder the flow of water as a whole.

  The planar arrangement of FIG. 6C is a plane in which a plurality of bumps 11 are arranged in a triangular shape as a whole by arranging one piece in the lateral direction X from the upstream side, then two pieces, and then placing two pieces at large intervals. The configurations 16, 17, and 18 are arranged in order in the water flow direction A. The respective solid bodies 11 are arranged at equal intervals in the vertical direction Y. Such a planar arrangement does not hinder the flow of water as a whole.

  6 (a) to 6 (c), the distance X1 between the bumps in the lateral direction X of each bump 11 in FIG. 7 is 1 to 3 times the width D of the bump in relation to the water flow direction A. The above is preferable. In addition, the distance Y1 between the three-dimensional solids in the longitudinal direction Y of each of the three-dimensional solids 11 in FIG. 7 is preferably 5 to 10 times the width D of the three-dimensional solids. Thus, the flow of water is not inhibited by arranging the plurality of bumps 11 in a plane.

  As shown in FIG. 6 and FIG. 7, the amount of the underwater deposit such as sand can be increased by arranging the plurality of impact bodies 11 in a plane so as not to inhibit the flow of water. Can be efficiently discharged in large quantities. In this case, it is preferable to arrange the plurality of bumps 11 in consideration of the characteristics of water flow.

  As described above, the modes for carrying out the present invention have been described. However, the present invention is not limited to these, and various modifications can be made within the scope of the technical idea of the present invention. For example, the structure of the three-dimensional structure may be the various shapes shown in FIGS. 2 to 5, but is not limited to these, and it is possible to efficiently accumulate underwater sediments such as sand without inhibiting the flow of water. Other shapes may be used.

  Further, the planar arrangement of the plurality of bumps in FIG. 6 may be other arrangements as long as they can efficiently accumulate underwater sediments such as sand without impeding the flow of water.

  In FIG. 3, the suction portion 21 and the pipe 22 for the accumulation prevention system are fixed in the vertical direction along the rear surface 11 b of the impact solid 11, but the discharge means of the present invention is not limited to this. For example, the suction part and the pipe may be arranged so that the suction part is positioned along the bottom G of FIG.

  Moreover, in many cases, the accumulated sediment discharged from the water is mainly sand, but it is a matter of course that it may contain silt or gravel. It is an object that accumulates and discharges so-called sediment deposited in the sedimentation area of the reservoir.

DESCRIPTION OF SYMBOLS 1 Dam 2 Reservoir 3 Sedimentation area 10 Deposit prevention structure 11 Impact solid 11a End part 11b Back surface 12-15 Impact solid 20 Accumulation prevention system 21 Suction part 22 Pipe 24 Suction pump A Water flow direction D Impact solid width G Bottom H Deposit I Groove

Claims (4)

Partition member composed of the installed extending from by sea urchin seabed against positive flow of water to the water surface near the upstream portion of the sedimentation zone and concrete structure in order to prevent deposition of water sediments in sedimentation zone of Reservoir A sedimentation prevention structure , wherein a plurality of sediments are installed so as not to impede the flow of water, and an underwater deposit is deposited near the bottom of the solid body . The deposition preventing structure according to claim 1 , wherein a discharge means for discharging the underwater sediment deposited near the bottom of the impact solid can be installed. The deposition preventing structure according to claim 1 or 2 ,
And a discharge means for discharging underwater deposits deposited in the vicinity of the bottom of the bumps of the deposit prevention structure. A deposition prevention method using the deposition prevention structure according to claim 1 or 2 , wherein the sediment deposited in the vicinity of the bottom of the solid body is discharged.

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