JP2003247222A - Soil accumulation structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a soil accumulation structure in a dammed lake efficiently dredging soil such as wash load and floating sand. <P>SOLUTION: This accumulation structure 1 for the soil is characterized in that a soil headrace 4 is formed from the upstream side of an inclined inflow channel 3 for passing water to the dam lake 2 to the lake bottom, and the soil headrace 4 comprises a lateral headrace levee 7 laterally projecting to close a part of the inclined inflow channel 3 in the upstream part of the inclined inflow channel 3 and a vertical headrace levee 8 constructed from the tip part of the lateral headrace levee 7 to the bottom of the reservoir along the inclined inflow channel 3. The lateral headrace levee 7 includes a separation levee constructed in its upstream side transversing the inclined inflow channel 3 and the soil headrace 4 is formed with a soil accumulation part 5 adjacent to its outlet. The soil accumulation part 5 is formed by constructing a soil accumulation area 14 adjacent to the outlet and dams 15 and 16 in a part properly separated from the tip of the vertical headrace levee 8 transversing the outlet 13. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sediment accumulation structure formed in dam lakes, reservoirs and rivers.

[0002]

2. Description of the Related Art Generally, dam lakes have almost no flow of water, and therefore, sediment such as fine-grained soil called floating roads and suspended sand that has flowed in with muddy water is deposited on the bottom of the lake. When the amount of this sediment increases, the amount of water storage decreases and the original function of the dam cannot be exerted. Therefore, dredging is performed by various methods.

[0003]

However, a wash load having an average particle size of about 0.017 mm and a particle size of 0.1.
Since the suspended sediment of 15 to 0.25 mm is deposited as a thin layer over the entire lake bottom, there is a problem that the dredging area becomes wide and efficient dredging cannot be performed.

The present invention has been made in view of the above problems, and an object thereof is to provide an integrated structure capable of efficiently dredging earth and sand.

[0005]

Means for Solving the Problems The gist of the earth and sand accumulation structure of the present invention for achieving the above objects is that a sand and sand guiding channel is formed from an upstream portion of an inflow slope road into which water flows to a lake bottom. The earth and sand conduit is located at the upstream side of the inflow slope road, and a lateral dike projecting laterally so as to block a part of the inflow slope road.
It is characterized in that it comprises a vertical flow bank constructed along the inflow slope road from the tip of the horizontal flow bank to the reservoir bottom. It also includes the construction of a diversion bank that crosses the inflow slope road on the upstream side of the horizontal dike. Further, a sediment collecting portion is formed near the outlet of the sediment guiding channel, and the sediment accumulating portion is located near the outlet and at an appropriate distance from the tip of the vertical dike. It includes that it was formed by a dam that was built so as to cross. In addition, it includes that the earth and sand guiding channel is gradually widened from the upstream side to the downstream side. It also includes the construction of a dam that extends in the direction opposite to the outlet at the tip of the longitudinal dike. It also includes the formation of silt protectors on the vertical dike. In addition, lateral dike, longitudinal dike and weir include embankment made of sediment discharged from the bottom of the reservoir.

[0006] Since muddy water containing wash roads and suspended sand flows into the dam lake (or reservoir) through the sediment channel, sediment such as wash roads and suspended sand is transferred to a predetermined portion of the dam lake, that is, the entire dam lake. Instead, it can be collected in some places. In addition, these sediments can be accumulated according to the shape of the dam lake at the location where the most efficient dredging is possible. In addition, large diversion stones and tree branches can be blocked by the diversion bank. Sediments such as wash roads and suspended sand that have flowed into the dam lake along with muddy water can be accumulated in the sediment accumulation area on the lake bottom. In addition, since the turbid water can be made to flow gradually from the upstream side to the downstream side by the sediment guiding channel that is gradually widened from the upstream side to the downstream side, sediment such as wash roads and suspended sand can be collected in the accumulation area for sediment. Can be accumulated. In addition, sediments such as wash roads and suspended sand can be accumulated in the accumulation area for sediments without diffusing from the dam provided at the tip of the longitudinal flow passage in the direction opposite to the outlet. Effective use of the sediment can be achieved by constructing the vertical dike and weir with the sediment discharged from the bottom of the lake. By accumulating sediments such as wash roads and suspended sediments at certain points of the dam lake, it is possible to perform efficient dredging work at one place, and to wash roads where it is possible to perform efficient dredging work. It is possible to accumulate sediment such as sand and suspended sand.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an integrated structure of earth and sand according to the present invention (hereinafter referred to as an integrated structure) will be described with reference to the drawings. In the respective embodiments, the same configurations will be described with the same reference numerals, and different configurations will be described with different reference numerals. This accumulation structure is formed in the dam lake, the reservoir, and the river. In the following embodiments, the accumulation structure formed in the dam lake will be described.

1 and 2 show an integrated structure 1 according to the first embodiment. This accumulation structure 1 is a flow path for sediment (hereinafter referred to as a “conduction path”) 4 for flowing muddy water containing sediment such as a wash road or suspended sand on an inflow slope path 3 for pouring water into a dam lake 2 and this flow direction. It is composed of a sediment accumulating portion (hereinafter referred to as accumulating portion) 5 formed near the outlet of the passage 4. In addition, the above-mentioned wash road refers to fine-grained soil having an average particle size of about 17μ, and suspended sand has a particle size of 0.15.
~ 0.25 mm of earth and sand.

The conduit 4 was built on the lateral dike 7 provided on the downstream side of the diversion wall 6 of the inflow slope 3 and on the inflow slope 3 from the tip of the lateral dike 7 to the lake bottom. It consists of a vertical dike 8. The lateral dike 7 and the longitudinal dike 8 are constructed by sedimentary soil discharged from the lake bottom, and the former blocks a part of the inflow slope road 3 from the right bank (toward the downstream side) to the left bank. The latter is constructed in this way, and the latter is constructed such that the conduit 4 gradually widens from the tip of the lateral conduit 7 to the lake bottom. A silt protector 9 is formed in the submerged portion of the vertical guideway 8 from the submerged portion to the tip.

As shown in FIG. 3, the silt protector 9 includes a curtain 10 suspended by a floater 10a.
The lower end of b is fixed to the submerged bank 8a.
Further, by providing a gap 10c of about 1 m between the floater 10a and the curtain 10b, the force acting on the silt protector 9 due to the water level difference between the inside of the lake and the conduit 4 is reduced.

The conduit 4 is formed on the left bank side in FIG. 1, but whether it is formed on the left or right can be determined in consideration of the hydraulic characteristics and topographical characteristics of the dam lake 2. Further, when the water depth of the inflow slope path 3 is shallow, the guide passage 4 can be formed by only the silt protector 9 or only the vertical diversion wall 8.

As in the case of natural rivers, muddy water 12 containing sediment such as wash roads and suspended sand slowly flows from the upstream side to the downstream side of the conduit 4 thus formed, and corresponds to the river mouth. The flow is designed to stop near the outlet 13.

On the other hand, the collecting portion 5 near the outlet 13
Is an accumulation area for sediment (hereinafter referred to as an accumulation area) 14
And dams 15 and 16 constructed by the sediment discharged from the lake bottom. The dams 15 and 16 thus formed around the accumulation area 14 form a recess, that is, an accumulation portion 5, near the outlet.
Therefore, the muddy water 12 containing sediment such as wash roads and suspended sand separated from large stones by the diversion bank 6 is
By flowing into the dam lake 2 from the conduit 4, it is retained at the front weir 15, and is not diffused elsewhere by the rear weir 16, so that sediment is deposited there.

4 and 5 show an integrated structure 17 according to the second embodiment. This accumulation structure 17 is characterized in that the accumulation portion 5 is formed in the recess portion where sediment such as wash roads and suspended sand easily accumulates by utilizing the topography of the dam lake 2, and is naturally formed near the outlet 13. The formed protrusions 18 replace the front dam 15 and form the stacking portion 5 together with the rear dam 16. As described above, the stacking structure 17 has the same configuration as the stacking structure 1 of the first embodiment except that the stacking portion 5 is formed by utilizing the topography of the dam lake 2. Therefore, similarly to the above, the turbid water 12 separated into large stones etc. by the diversion dike 6 flows into the dam lake 2 from the conduit 4, is fixed by the protrusions 18, and is further separated by the dam 16 on the rear side. It does not spread.

[0015]

[Effects of the Invention] Since muddy water containing sediment such as wash roads and suspended sand flows into the dam lake through the conduit, the sediment is not collected at a predetermined location of the dam lake, that is, the entire dam lake.
It can be accumulated at a certain place.

[0016] Sediments such as wash roads and suspended sand can be accumulated according to the shape of the dam lake at the location where the most efficient dredging is possible.

Large diversion stones and tree branches can be dammed by the diversion bank.

Sediments such as wash roads and suspended sand that have flowed into the dam lake together with muddy water can be accumulated in the accumulation area on the bottom of the lake.

Since the turbid water can be made to flow gradually from the upstream side to the downstream side by the guiding passage formed gradually wider from the upstream side to the downstream side, sediment such as wash road and suspended sand is accumulated in the accumulation area. be able to.

By the dam, sediment such as wash roads and suspended sand can be collected in the accumulation area without being diffused.

[0021] Lateral lateral dike with sediment discharged from the bottom of the lake,
Since the vertical and horizontal diversion dams and dams have been constructed, the accumulated soil can be effectively used.

Sediments such as wash roads and suspended sediment can be accumulated at certain points of the dam lake, so that the dredging work can be performed efficiently, and the sediments can be placed at the places where the efficient dredging work can be performed. Can be integrated.

[Brief description of drawings]

FIG. 1 is a plan view of an integrated structure according to a first embodiment.

FIG. 2 is a vertical sectional view of FIG.

3 (1) is a transverse sectional view of FIG. 1, and FIG. 3 (2) is a front view of the silt protector.

FIG. 4 is a plan view of an integrated structure according to a second embodiment.

5 is a cross-sectional view of FIG.

[Explanation of symbols]

1,17 Integrated structure 2 dam lake 3 Inflow slope road 4 channel 5 accumulation section 6 diversion bank 7 Lateral bank 8 Vertical flow bank 9 silt protector 10a floater 10b curtain 10c gap 12 muddy water 13 Outlet 14 accumulation area 15, 16 dam 18 Projection

Claims (7)

[Claims] 1. A sediment guide passage is formed from an upstream portion of an inflow slope passage into which water flows to a reservoir bottom, and the sediment guide passage closes a part of the inflow slope passage to an upstream portion of the inflow slope passage. Accumulation of sediment, which consists of a lateral dike projecting laterally like this and a longitudinal dike constructed along the inflow slope road from the tip of the lateral dike to the reservoir bottom. Construction. 2. The earth and sand accumulation structure according to claim 1, wherein a diversion bank which crosses the inflow slope road is constructed upstream of the lateral dike. 3. A sediment accumulating portion is formed near the outlet of the sediment guiding passage, and the sediment accumulating portion is appropriately separated from the sediment accumulating area near the outlet and the tip of the vertical dike. The earth and sand accumulation structure according to claim 1 or 2, wherein the accumulation structure is formed by a dam that is built at a location so as to cross the outflow port. 4. The sediment guiding channel is formed so as to gradually widen from the upstream side to the downstream side.
Accumulation structure of earth and sand described in any one of. 5. The weir, which extends in the direction opposite to the outlet, is built at the tip of the longitudinal dike.
The earth and sand accumulation structure according to any one of 4 above. 6. The accumulated structure of earth and sand according to claim 1, wherein a silt protector is formed on the vertical flow bank. 7. The sediment accumulation structure according to any one of claims 1 to 6, wherein the lateral dike, the longitudinal dike, and the weir are constructed by sedimentary soil discharged from the lake bottom.