JP2007321401A - Inclined revetment and seawater purifying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inclined revetment capable of purifying the seawater in the vicinity of the bottom of the sea easily by a simple configuration and by utilizing natural energy such as tide. <P>SOLUTION: This inclined revetment 1 provided along a coastline is provided with a revetment main body 2 constituted by stacking at least two revetment layers 3, 15 having different water passing properties in the vertical direction. The revetment main body 2 is constituted by providing the revetment layer 15 having relatively low water passing property on an upper layer side and the revetment layer 3 having relatively high water passing property on a low layer side, and end parts 7, 10 on a land side and a sea side of the revetment layer 3 on the low layer side are extended onto a land side and a sea side more than the revetment layer 15 on the upper layer side, respectively. The revetment layer 3 on the low layer side is constituted by spreading a plurality of back-filling materials 4 all over the ground on the bottom of the sea 20 along the coastline, and the revetment layer 15 on the upper layer side is constituted by spreading a plurality of back-filling materials 16 having smaller dimension than that of the back-filling materials 4 for the revetment layer 3 on the low layer side in an upper part of the revetment layer 3 on the low layer side. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an inclined revetment and a seawater purification method, and more particularly to an inclined revetment having a seawater purification function and a seawater purification method using the inclined revetment.

  In general, there are embankments such as upright revetments along the coastline to prevent inundation and erosion due to storm surges, waves, tides, etc. In recent years, it has been practiced to install a sloped revetment on the front side (sea side) of an existing embankment, or to destroy the existing embankment and newly install a slope revetment.

  By the way, when an inclined revetment is constructed along the coastline, seawater can be sufficiently purified near the sea surface due to strong tides, waves, tides, etc. However, the seawater cannot be sufficiently purified, an oxygen-poor water area is formed, and the natural environment near the coast is deteriorated.

In order to solve the above-described problem of forming an anoxic water area, Patent Document 1 discloses a semi-enclosed sea area in which an outer facility is provided on the sea side of a seawall facility, and seawater enters between the two at a high water level. A pond on the land side of the revetment facility, connecting the semi-enclosed sea area and the pond with a discharge pipe, and connecting the sea floor and the pond with a discharge pipe Then, the seawater in the semi-enclosed sea area is guided to the scenic pond through the drainage pipe, and the seawater in the scenic pond is guided to the seabed through the drainage pipe (that is, the seawater is circulated between the sea and the scenic pond. A seawater purification structure configured as described above has been proposed.
No. 7-13766

  However, in the seawater purification structure configured as described above, it takes time and labor to construct the outer facility, construct the landscape pond, lay the discharge pipe, etc., and the construction period is prolonged and the construction cost is high. I'm stuck. In addition, since a power source such as a pump is required to circulate seawater, electric power for driving the power source is required, resulting in high running costs.

  The present invention has been made in view of the conventional problems as described above, and can reduce the time and labor required for construction, shorten the construction period, reduce the construction cost, and reduce the running cost. An object is to provide an economically advantageous slope revetment and seawater purification method that does not require cost.

In order to solve the above problems, the present invention employs the following means.
That is, the invention according to claim 1 is an inclined revetment provided along the coastline, and includes a revetment main body formed by laminating at least two revetment layers having different water permeability in the vertical direction. A revetment layer with low water permeability is provided on the upper layer side, a revetment layer with relatively high water permeability is provided on the lower layer side, and the revetment layer on the lower layer side has its land and sea side ends. It is characterized by extending to the land side and the sea side from the upper revetment layer.

  According to the slope revetment according to the present invention, when storm surges, waves, tides, etc. act on the slope revetment, a part of seawater including air flowing over the revetment layer on the upper side of the revetment main body to the land side is caused by the head difference. It flows into the revetment layer on the lower layer side of the revetment body, circulates in the revetment layer on the lower layer side, and is led to the sea floor on the sea side than the revetment layer on the upper layer side of the revetment body, and oxygen is supplied to the seawater near the seabed. Will be purified.

  The invention according to claim 2 is the inclined revetment according to claim 1, wherein the lower revetment layer is configured by laying a plurality of backing materials on the seabed ground along the coastline, and the upper layer The side revetment layer is configured by laying a backing material having a size smaller than that of the lower revetment layer on the upper side of the lower revetment layer.

  The invention according to claim 3 is the inclined revetment according to claim 1 or 2, wherein at least a part between the lower revetment layer and the upper revetment layer is insulated between them. It is characterized by interposing a water shielding layer.

  According to the inclined revetment according to the present invention, at least a part of the lower revetment layer and the upper revetment layer is shielded by the water shielding layer interposed between them. The distribution of seawater between the two revetment layers through the water layer is blocked, and the seawater that flows into the land side beyond the upper revetment layer can be efficiently guided to the lower revetment layer.

  The invention according to claim 4 is the inclined revetment according to any one of claims 1 to 3, wherein an upright revetment is provided along the coastline, and the upright revetment along the upright revetment on the sea side. It is characterized by having a seawall body.

  The invention according to claim 5 is an inclined revetment provided along the coastline, comprising a revetment main body formed by laminating at least two revetment layers in the vertical direction, and the revetment main body includes an upper revetment layer, A lower side revetment layer, at least the lower side revetment layer has water permeability, and the lower side revetment layer has a land side and sea side end that is more land than the upper revetment layer. Each extending to the sea side and the sea side, and at least a part between the lower side revetment layer and the upper side revetment layer is provided with a water shielding layer for shielding water between them. To do.

  The invention according to claim 6 is a seawater purification method for purifying seawater in an anoxic water area near the coast, wherein the inclined revetment according to any one of claims 1 to 5 is provided along the coastline. The seawater that flows into the land side beyond the upper revetment layer is guided to the sea floor on the sea side of the upper revetment layer through the revetment layer on the lower side of the revetment main body, and the seawater near the sea floor is purified. It is characterized by that.

As described above, according to the slope revetment and seawater purification method according to the present invention, when storm surges, waves, tides, etc. act on the slope revetment, oxygen flowing into the land side beyond the revetment layer on the upper side of the revetment main body A part of the seawater contained flows into the revetment layer on the lower layer side of the revetment main body due to the water head difference, circulates in the revetment layer on the lower layer side, and is guided to the sea floor on the sea side from the upper revetment layer. Therefore, since oxygen-containing seawater can be supplied to the anoxic water area near the seabed, the seawater in the water area can be purified, and the existing seawall of the upright revetment etc. is inclined to the sea side of the embankment. Even if a revetment is constructed, the natural environment is not deteriorated.
In addition, the revetment main body has a simple structure in which at least two revetment layers with relatively different water permeability are stacked in the vertical direction, so that construction time and labor can be reduced. The construction cost can be reduced.
Furthermore, since the seawater can be purified using natural energy from seawater such as storm surges, waves, and tides, it is possible to continue the purification of seawater without the need for running costs. Can be provided.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment of an inclined revetment according to the present invention. This inclined revetment 1 can be applied to an embankment such as an upright revetment (upright revetment 25 in this embodiment) provided along the coastline, and has a function of protecting and reinforcing the upright revetment 25, and an upright revetment, And the function of exchanging seawater in an anoxic seawater area near the seabed 20 along 25.

  The upright revetment 25 vertically places a plurality of steel sheet piles 26 along the coastline, and inputs a backing material 27 made of rubble or the like on the land side sectioned by the plurality of sheet piles 26 from the sea side. Then, a concrete plate 28 is laid on top of the backing material 27, and the inclined revetment 1 according to the present embodiment is provided along the sea side of the upright revetment 25.

  The inclined revetment 1 according to the present embodiment is laminated on the bottom of the seabed 20 on the sea side of the upright revetment 25, and the lower revetment layer 3 laminated along the entire length of the upright revetment 25 and the upper part of the lower revetment layer 3. A revetment main body 2 having a three-layer structure comprising a upper revetment layer 15 and a water shielding layer 14 interposed between the upper revetment layer 15 and the lower revetment layer 3 is provided.

  The lower revetment layer 3 is formed by placing and placing a backing material 4 made of reclaimed waste, such as rubble, concrete gravel, etc., along the upright revetment 25 on the ground of the seabed 20 on the sea side of the upright revetment 25. The water permeability is given by the gap formed between the backing materials 4.

  The size and type of the backing material 4 are set so that the lower revetment layer 3 has higher water permeability than the upper revetment layer 15 described later, and oxygen flowing into the upright revetment 25 side beyond the upper revetment layer 15 is set. A part of the contained seawater flows into the lower revetment layer 3 due to a water head difference, flows through the lower revetment layer 3, and is guided to the seabed 20 on the sea side from the upper revetment layer 15.

  The lower revetment layer 3 has a lower surface 5 formed on a gently inclined surface along the inclination of the seabed 20, and an upper surface 6 formed on an inclined surface having an inclination angle tighter than that of the lower surface 5. 7 extends to the land side from the end portion on the land side of the upper revetment layer 15 to be described later, and is in close contact with the sheet pile 26 of the upright revetment 25, and the sea side end portion 10 is the end on the sea side of the upper revetment layer 15 to be described later. It extends to the sea side from the section and is exposed on the seabed 20.

  A concave portion 12 having a substantially triangular cross section is provided on the upper surface 6 of the lower revetment layer 3 over the entire length in the longitudinal direction (the direction along the coastline), and the upper revetment layer 15 is formed in the concave portion 12 via a water shielding layer 14. Are stacked. The water-impervious layer 14 is laminated with a predetermined thickness over the entire recess 12, and the water-impervious layer 14 shields water between the lower revetment layer 3 and the upper revetment layer 15.

  Examples of the water shielding layer 14 include a water shielding sheet made of rubber or synthetic resin, a metal water shielding plate, a concrete plate, and the like. However, it does not limit to these, What is necessary is just to have a function which can water-shield between the lower revetment layer 3 and the upper revetment layer 15.

  The water shielding layer 14 does not necessarily need to be provided over the entire recess 12, and may be provided only at least on the land side half of the recess 12. In short, in order to efficiently guide the seawater containing oxygen flowing into the end 7 of the lower revetment layer 3 over the upper revetment layer 15 to the inside of the lower revetment layer 3, What is necessary is just to be able to form the part intercepted by water from the periphery at the end part 7.

  The upper revetment layer 15 is formed by placing and placing a backing material 16 made of reclaimed waste such as rubble and concrete on the upper part of the water shielding layer 14 in the recess 12 of the lower revetment layer 3. Thus, predetermined water permeability is given by the gap formed between the backing materials 16. In this case, the size and type of the backing material 16 are set so that the upper revetment layer 15 has lower water permeability than the lower revetment layer 3 described above.

  A plurality of rectangular plate-like concrete blocks 17 are laid throughout the upper revetment layer 15. In this case, the position of the upper surface of the upper revetment layer 15 laminated in the recess 12 of the lower revetment layer 3 so that the upper surface of the block 17 and the upper surface 6 exposed in the sea of the lower revetment layer 3 are flush with each other. The tilt angle is adjusted.

  As described above, the end 7 on the land side of the lower revetment layer 3 extends to the land side from the end on the land side of the upper revetment layer 15 and is located between the upright revetment 25 and the upper revetment layer 15. An inflow portion 8 having an upper opening is provided at that portion. A part of the seawater containing oxygen flowing into the upright revetment 25 through the upper revetment layer 15 through the inflow portion 8 is introduced into the lower revetment layer 3 due to a water head difference. The surface of the inflow portion 8 on the side of the upper revetment layer 15 is formed on an inclined surface 9 having a predetermined angle, and the inclined surface 9 makes it easy to guide seawater over the inclined revetment 1 to the inflow portion 8.

  Further, as described above, the sea-side end portion 10 of the lower revetment layer 3 extends to the sea side from the sea-side end portion of the upper revetment layer 15, and the outflow portion 11 whose upper surface is exposed in the sea. The seawater that has flowed into the lower revetment layer 3 from the inflow portion 8 is guided to the seabed 20 through the outflow portion 11.

  The inflow portion 8 of the lower revetment layer 3 is formed one step lower than the end of the upper revetment layer 15 on the land side, so that the oxygen-containing seawater flowing into the upright revetment 25 side over the upper revetment layer 15 is temporarily stored. By collecting in the inflow part 8, it is easy to guide to the lower revetment layer 3. In addition, when the water permeability of the lower revetment layer 3 is high, the inflow part 8 does not need to be formed low.

  And when seawater acts on the inclined revetment 1 according to the present embodiment configured as described above due to storm surges, waves, tides, etc., seawater that has taken in a large amount of oxygen by breaking waves passes over the upper revetment layer 15 of the revetment body 2. It flows into the upright revetment 25 side, and a part of the seawater flows into the lower revetment layer 3 from the inflow part 8 of the lower revetment layer 3 due to a head difference, and flows through the lower revetment layer 3 and is led to the outflow part 11. It flows out from the outflow part 11 to the seabed 20 side, a flow of seawater is generated in the vicinity of the seabed 20, and oxygen is supplied to the vicinity of the seabed 20 to be purified.

  Therefore, when the sloped revetment 1 is constructed on the sea side of the upright revetment 25 due to the aging of the upright revetment 25, the sloped revetment 1 does not form an anoxic water area on the sea floor near the coast, thus protecting nature. Can be achieved.

  Further, the lower revetment layer 3 and the upper revetment layer 15 of the revetment main body 2 of the inclined revetment 1 have a simple structure in which backing materials 4 and 16 having different sizes and the like are laid down, and a water shielding layer. 14 also has a simple structure composed of a water shielding sheet, a water shielding plate, etc., so that the time, labor, and cost required for construction can be greatly reduced, the construction period can be shortened, and the construction cost can be reduced. It can be greatly reduced.

  In addition, since natural energy from seawater such as storm surges, waves, and tides is used, it is not necessary to circulate seawater with a power source such as a pump, and running costs are not required, providing economically advantageous things. Can do.

  Furthermore, by arbitrarily setting the width, length, and thickness of the lower revetment layer 3 and the upper revetment layer 15 of the revetment main body 2, it is possible to purify seawater near the sea bottom at any position near the coast. Therefore, versatility can be improved.

  In the above description, the revetment main body 2 is composed of one lower revetment layer 3, one upper revetment layer 15 and one water-impervious layer 14, but the lower revetment layer 3 and the upper revetment layer 15. The water shielding layer 14 may be two or more layers.

  In the above description, water permeability is given to both the lower revetment layer 3 and the upper revetment layer 15 and the water-impervious layer 14 having water-imperviousness is interposed between them. The upper revetment layer 15 may be formed by providing water permeability to the recess 12 of the lower revetment layer 3 to form a water revetment layer 15, or the surface of the revetment main body 2 having water impermeability. The upper revetment layer 15 may be formed by placing the like. In that case, since the upper revetment layer 15 can function as a water-impervious layer, it is not necessary to interpose the water-impervious layer 14 between the lower revetment layer 3 and the upper revetment layer 15.

It is the schematic which showed the whole one Embodiment of the slope revetment by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inclined revetment 2 Revetment main body 3 Lower revetment layer 4, 16, 27 Backing material 5 Lower surface 6 Upper surface 7 End portion 8 Inflow portion 9 Inclined surface 10 End portion 11 Outflow portion 12 Recessed portion 14 Impermeable layer 15 Upper revetment layer 17 Block 20 Seabed 25 Upright revetment 26 Sheet pile 28 Concrete plate

Claims (6)

An inclined revetment along the coastline,
It is equipped with a revetment main body that consists of at least two revetment layers with different water permeability and stacked vertically.
The revetment main body is provided with a revetment layer with relatively low water permeability on the upper layer side, a revetment layer with relatively high water permeability is provided on the lower layer side, and the revetment layer on the lower layer side is the land side and An inclined revetment characterized in that the sea end extends to the land side and the sea side from the upper revetment layer.   The lower-side revetment layer is configured by laying a plurality of backing materials on the seabed ground along the coastline, and the upper-side revetment layer is located above the lower-side revetment layer, on the lower-side revetment layer. The inclined revetment according to claim 1, wherein the revetment is constructed by spreading a backing material having a smaller size than the backing material of the revetment layer.   The at least part between the said lower-layer side revetment layer and the said upper-layer side revetment layer is made to interpose the water-impervious layer which water-blocks between them, The Claim 1 or 2 characterized by the above-mentioned. Inclined revetment.   The upright revetment is provided along the coastline, and the revetment main body is provided along the upright revetment on the sea side of the upright revetment. An inclined revetment along the coastline,
It has a revetment main body that consists of at least two revetment layers stacked vertically,
The revetment main body has a revetment layer on the upper layer side and a revetment layer on the lower layer side, at least the revetment layer on the lower layer side has water permeability, and the revetment layer on the lower layer side has its land side and sea side The end portion of the upper wall extends to the land side and the sea side from the upper revetment layer, and at least part of the space between the lower revetment layer and the upper revetment layer is insulated between them. An inclined revetment characterized by a water barrier layer. A seawater purification method for purifying seawater in anoxic waters near the coast,
The inclined revetment according to claim 1 is provided along the coastline, and the seawater flowing into the land side beyond the revetment layer on the upper layer side of the revetment main body is connected to the upper layer side through the revetment layer on the lower layer side of the revetment main body. A seawater purification method characterized in that the seawater near the seabed is purified by guiding it to the seabed on the sea side of the seawall.