JPH07286316A - Shore protection method - Google Patents

Abstract

PURPOSE:To prevent the seashore from being eroded, by installing two or more shore-protection structures provided with longitudinal embankment and two or more lateral embankments installed with a distance in the longitudinal embankment, with an interval toward the off shore. CONSTITUTION:A longitudinal embankment 1 extending to the offshore and two or more lateral embankments 3, 3' almost parallelly extending to the beach 2 at least at two positions of the embankment 1 with a distance, are arranged to form sore protection structures A1, A2, A3 respectively. The structures A1, A2, A3 are arranged from the beach 2 to the offshore with an interval. Seawater flows from the distance between the front ends of A1, A2, and also A2, A3 into the area surrounded by the structures A1, A2, A3 and the transferred sands (a) collide with the embankments 3, 3' complicatedly and the energy is reduced and the sands are piled there. The surrounded water area is not affected by waves and kept calm. The piled sands are not transferred again and hence, the beach is kept stable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a revetment structure for installation in water bodies such as coasts, rivers, lakes, harbors and artificial islands, and a revetment method using the revetment structure. In detail, it has a good revetment in the above water area,
A revetment structure that has a wave-dissipating function, a shoreside erosion prevention function, and a sand-scattering prevention function, and can artificially form beaches in these waters to achieve effective use of the waters and increase the area of the beaches. , And seawall method.

[0002]

2. Description of the Related Art Nature on the waterfront such as coasts, beaches, shores of rivers and lakes is extremely valuable in that it has the function of relaxing the mind and body of human beings, and it inhabits many waterfronts including fish and birds. It has also become extremely important for animals and plants. In addition, if there are sandy beaches near the coast, sandy beaches, shores of rivers and lakes, etc., many microbes will live there, and these microbes will promote the purification of water. Is also important from the point of.

However, despite the fact that Japan is surrounded by the sea and the coastline itself is extremely long, there are few watersides such as sandy beaches, which are highly safe for people to gather and touch the water and enjoy the flora and fauna. There are very few beaches that can be formed, and in recent years, such precious beaches and beaches have been decreasing due to various factors such as erosion on coasts and rivers, development work, and water pollution.

On the other hand, revetment work has been conventionally carried out for the purpose of preventing waves and winds from eroding coasts of rivers and rivers, and preventing waves from disappearing, erosion, and flying sand. As such a conventional method, as shown in FIG.
As shown in Figure 1, a method of installing revetments 1 consisting of wave-dissipating blocks and water-permeable levee revetments from the shore 2 toward the offshore in the longitudinal direction with multiple rows spaced, as shown in Fig. 1 (b). A method of installing a revetment 3 composed of a wave block and a water-permeable levee bank almost parallel to the shore 2, or as shown in Fig. 1 (c), a revetment 1 composed of a wave-dissipating block and a permeable levee offshore from shore 2. Are installed in the vertical direction with a plurality of rows spaced apart from each other, and a horizontal revetment 3 is provided at the tip end thereof in a direction substantially parallel to the shore 2.
A method of installing in a character shape is known.

However, in the case of the above-mentioned conventional method in which a plurality of banks 1 are installed in the vertical direction, the collision energy of waves at the offshore tip portion of the bank 1 is large, and the sandy beach at that portion is largely eroded so that the bank 1 is removed. There are many damages such as sinking. Further, in the case of the above-mentioned conventional method in which the revetment 3 is installed substantially parallel to the shore 2, the erosion rate of the sand beach on which the revetment 3 is installed is slow as much as possible, and it is difficult to completely prevent erosion. Further, in the case of the above-mentioned conventional method in which the horizontal revetment 3 is installed in a T shape at the tip of the vertical revetment 1, sand is accumulated on the back surface portion 4 of the horizontal revetment 3 to form a beach. However, since the sandy beach is extremely small in area and is formed far away from the shore 2 (usually 50 m or more), the sandy beach cannot be reached. There is a drawback that people cannot easily use the beach as a beach by the beach for leisure or leisure.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to strongly prevent shores, rivers, lakes, lakes, ponds, artificial islands, harbors and other shores from being eroded by waves and winds, and have a wave-dissipating function. Another object of the present invention is to provide a revetment structure and a revetment method that are excellent in sand-scattering prevention function. Furthermore, the present invention, together with the various functions described above, is a beach that can be enjoyed by humans, is extremely valuable for flora and fauna that inhabit the waterside, and is also extremely important for the purification of water where useful microorganisms inhabit. To provide a revetment method and a revetment structure capable of increasing the sandy beach area.

[0007]

As a result of repeated studies by the present inventor to achieve the above object, at least two locations of a vertical seawall extending toward the offshore and the vertical seawall are spaced apart. When two or more lateral revetments are provided to construct a revetment structure and two or more revetment structures are installed at intervals from the shore toward the offshore, the water area surrounded by these revetment structures is The energy of waves and wind is small and calm, moreover, a large amount of sand flows into and is deposited in the surrounding water area, and the deposited sand is carried away from the water area by the waves and disappears. Without
The present invention has been completed by discovering that a sandy beach of a considerable area is formed in the water area where humans can enjoy and flora and fauna of the waterside can inhabit microorganisms.

That is, the present invention provides a revetment structure comprising a longitudinal revetment extending offshore and two or more lateral revetments provided at intervals in at least two locations of the longitudinal revetment. Alternatively, it is a revetment method characterized by installing two or more from the location adjacent to the shore toward the offshore.

Then, the present invention provides a shore structure comprising a longitudinal seawall extending offshore and two or more lateral seawalls provided at intervals at least at two positions of the longitudinal seawall. Alternatively, it is a revetment structure characterized by being installed two or more at intervals from the location adjacent to the shore toward the offshore.

Furthermore, the present invention is a revetment structure having a longitudinal revetment extending offshore and two or more lateral revetments provided at intervals in at least two locations of the longitudinal revetment.

The term "shore" as used in the present invention means a shore at a waterside called so-called waterfront, such as a shore, a river shore, a lake shore, a pond shore, an artificial island shore, Examples include the shore of a port. However, the present invention is not limited to these, and any waterside shore where formation of a revetment and a beach is beneficial is a subject of the present invention. The term "place adjacent to the shore" means a sandy beach, a wetland existing adjacent to the shore, or a place near the shore such as the sea, rivers, lakes and ponds.

The term "longitudinal revetment extending offshore" as used in the present invention refers to a shore or a place adjacent to the shore,
A seawall that extends toward the offshore of waters such as lakes, rivers, and ponds. A vertical revetment is at right angles to the shore or near to the shore depending on various conditions such as the type of water environment in which it is installed, the direction and speed of the water flow at the location, wave and wind conditions, and other weather conditions. It may be installed at a right angle toward the offshore, or may be installed at an angle to the shore with a slight deviation from the right angle, and generally installed at a right angle or almost at a right angle to the shore. It is preferably installed. The length and width of the vertical revetment are not particularly limited, and can be appropriately determined according to the type and condition of the water environment in which the revetment structure of the present invention is installed. Generally, it is preferable that the length of the longitudinal revetment is about 20 to 100 m and the width is about 50 cm to 3 m. Further, the vertical revetment may be straight or may be slightly curved in some cases.

Further, in the present invention, it is necessary to provide two or more lateral revetments at intervals with respect to the above-mentioned longitudinal revetment, and one of the two or more lateral revetments is It should be installed at or near the tip of the longitudinal revetment. When the number of lateral seawalls is only one as in the above-mentioned conventional method, only a small area of sand beach is occasionally formed on the inner side of the lateral seawall at its tip, and the sand beach forming function is It is not possible to achieve the object of the invention of forming a very low and wide beach. If the number of lateral revetments is two or more, the upper limit is not particularly limited. It may be appropriately determined according to the length of the vertical revetment installed offshore, the state of the water environment where the revetment structure of the present invention is installed, and the like. Generally, the distance between adjacent lateral revetments is about 3
It is advisable to provide two or more lateral revetments on the longitudinal revetment at intervals of 0 to 70 m.

In the above case, it is preferable that the lateral revetment is provided such that both arms extend on both sides of the same position of the longitudinal revetment. However, in the case of the outermost revetment structure, the lateral revetment may be provided only on the inner side and the lateral revetment may not be provided on the outer side. The installation angle of the horizontal revetment with respect to the vertical revetment is preferably a right angle or a substantially right angle, but is not necessarily limited thereto, and the angle formed by the vertical revetment and the horizontal revetment is 7
It may be provided in a range of 0 ° to 110 °.

The length and width of the lateral revetment are not particularly limited and may be appropriately determined depending on the type and condition of the water environment in which the revetment structure of the present invention is installed and the length and width of the longitudinal revetment. Yes, but generally, the length from the base of the horizontal revetment to the vertical revetment to the tip of the horizontal revetment is about 1
The width of the lateral revetment is about 0 to 40 m, and the width of the lateral revetment is about 50 cm to 3
It is better to keep it around m. The lateral revetment may be straight or slightly curved.

In the revetment method of the present invention, a revetment structure having the above-mentioned longitudinal revetment and two or more lateral revetments is provided at intervals from the shore or a place adjacent to the shore toward the offshore. Install two or more to form a body of water surrounded by two revetment structures. In that case, the interval between adjacent revetment structures may be appropriately determined according to the state of the water environment where the revetment structures are installed, etc. Generally, in the longitudinal revetment in one revetment structure and the adjacent revetment structure The distance to the longitudinal seawall is preferably about 30 to 100 m. At that time, a horizontal revetment provided at or near the tip of the longitudinal revetment of one revetment structure,
Adjacent two of them are formed so as to form a gap (interval) through which water flows or waves enter and leave between the end of the longitudinal revetment of the adjacent revetment structure or the opposing lateral revetment provided in the vicinity thereof. It is necessary to determine the distance between two revetment structures and the length of the lateral revetment provided in the longitudinal revetment of the revetment structure. The height of the vertical revetment 1 and the lateral revetment 3 from the water surface is preferably about 70 cm to 2 m.

Although not limited thereto, in order to facilitate understanding of the content of the present invention, the present invention will be specifically described below with reference to the drawings. FIG. 2 is a view of a typical example of the revetment method and revetment structure of the present invention when viewed from above, in which the foreground is on the shore side and the upper part is offshore. In the revetment structure of the present invention, a longitudinal revetment 1 extending toward the offshore and two or more lateral revetments 3 and 3 ′ are provided in at least two places of the longitudinal revetment 1 at a distance from each other substantially parallel to the shore 2. Provided to form respective revetment structures A ₁ , A ₂ , A ₃ ... And these revetment structures A ₁ , A ₂ , A ₃ ... Offshore from the shore 2 or a place adjacent to the shore 2. towards, at intervals, as _{a 1, a 2, a 3} ··· as shown in FIG. 2, it is necessary to install two or more.

Although not limited, in the revetment structure shown in FIG. 2, the length L ₁ of the longitudinal revetment 1 is about 30 to 100 m and the width W ₁ of the longitudinal revetment 1 is as described above. 50 cm to 3 m, the length L ₂ of one arm of the lateral revetment 3, 3 ′ is about 10 to 40 m, the width W ₂ of the lateral revetment 3 and 3 ′ is about 50 cm to 3 m, and adjacent revetment structures The distance L ₃ between the bodies A ₁ and A ₂ is about ₃₀ to 100 m, and the gap W ₃ between the lateral revetment 3 and the lateral revetment 3 provided at the tips of the adjacent revetment structures A ₁ and A _2. Is preferably about 10 to 70 m. The distance L ₅ between the 'distance L ₄ and lateral revetment 3 between the' a shore lateral seawall 3 and lateral seawall 3 idea to about 30~70m as described above is well In that case, the length of L _{4 and} the length of L ₅ may be the same or different.

In the above case, in the adjacent revetment structure A ₁ and revetment structure A ₂ , the lateral revetment 3 and the lateral revetment 3 facing each other, and the lateral revetment 3'and the lateral revetment 3'are arranged. It may be at the same position as shown in FIG. 2 or at a slightly deviated position. That is, in the revetment structure A ₁ and the revetment structure A ₂ , L ₄ and L ₅ may have the same length or different lengths. In order to smoothly form the sand in water surrounded by revetment structure A ₁ and shore protection structures A ₂ are transverse seawall 3 facing each other in the revetment structure A ₁ and shore protection structures A ₂ adjacent the lateral Directional seawall 3, and lateral seawall 3'and lateral seawall 3 '
It is preferred that and are in the same position.

Among the above, the water area surrounded by two adjacent revetment structures A ₁ and A ₂ , A ₂ and A _3, etc. (two adjacent longitudinal revetments 1 and each longitudinal revetment 1 It is preferable that the shape of the water area surrounded by the lateral revetment 3 provided at the tip end of is substantially square. The height of the vertical revetment 1 and the horizontal revetments 3, 3'from the water surface is preferably about 70 cm to 2 m as described above.

In the revetment structure of FIG. 2, the longitudinal revetment 1 is provided at a substantially right angle to the shore 2, but it need not always be at a right angle, and the installation angle θ ₁ of the longitudinal revetment 1 with respect to the shore 2 is generally. It can be selected and determined from the range of about 70 ° to 110 °. In addition, in the revetment structure of FIG. 2, the lateral revetments 3, 3 ′ are provided at right angles to the longitudinal revetment 1, but they need not be at right angles, and the lateral revetments 3, 3 with respect to the longitudinal revetment 1 are provided. The installation angle θ ₂ of the'can be selected and determined from the range of about 60 ° to 100 °. In addition, in FIG. 2, the horizontal revetment 3 is provided at the forefront of the vertical revetment 1,
In some cases, the horizontal revetment 3 may be provided slightly closer to the bank 2 than the tip of the vertical revetment 1.

Further, in FIG. 2, two (two rows) lateral revetments 3, 3'are spaced from each longitudinal revetment 1.
However, the number of lateral revetments may be three or more depending on the length of the longitudinal revetment 1 and the like.
The length of the lateral revetment 3 and the length of the lateral revetment 3'may be the same or different, and if different, the lateral revetment 3 provided at the tip of the longitudinal revetment 1 or in the vicinity thereof It is preferable to make it longer than the lateral revetment 3'from the shore 2 from the viewpoint of promoting the formation of the beach. In FIG. 2, the revetment structures A ₁ , A ₂ , A ₃ ... In which the lateral revetments 3, 3 ′ are provided with their arms extended with respect to the longitudinal revetment 1, are installed. Without limitation, in the outermost revetment structures A ₁ and A ₄ as shown in FIG. 3, the lateral revetment 3, 3 '
May be provided only on the inner side (one side) of the vertical revetment 1.

In the revetment structure shown in FIG. 2, the lateral revetment 3 provided at the tip of the longitudinal revetment 1 has a substantially linear shape.
For example, the horizontal revetment 3 provided at the tip of the vertical revetment 1,
The shape may be slightly curved inward (recessed) as shown in FIG. 4A, or conversely may be curved outwardly as shown in FIG. 4B. When the lateral revetment 3 has the shape shown in FIG. 4 (a), the wave-dissipating effect is large, while when the lateral revetment 3 has the shape shown in FIG. 4 (b), the formation of a beach is promoted. effective.

In the present invention, two or more of the above-mentioned revetment structures A ₁ , A ₂ , A ₃ ... Are installed at intervals on the shore or at a place adjacent to the shore so that adjacent revetments are provided. Water flows from the gap between the tips of the structures A ₁ and A ₂ and the gap between the tips of A ₂ and A ₃ into the body of water surrounded by the revetment structure, and the sand carried by the water flow or water flow. Is complicatedly collided with or blocked by the lateral revetment 3 and the lateral revetment 3'provided inside the water area, significantly reducing its energy and depositing sand on those places. Thus, a sandy beach a as shown in FIG. 5 is formed around the vertical revetment 1 and the lateral revetments 3, 3 '.

The revetment structure A ₁ , A ₂ , A ₃ ...
Since the waters and sand beaches surrounded by the vertical revetment 1 and the horizontal revetment 3 are in a calm state with little influence of waves and winds, the sand accumulated there is waved out of the surrounding waters. Less often carried away by
You can keep the beach in a stable condition. Further, in some cases, sand may be transported from the outside by a truck or the like to the water area surrounded by the revetment structures A ₁ , A ₂ , A ₃ ... to form a sand beach, or the sand may be replenished. Also in this case, the water area and the beach surrounded by the longitudinal seawall 1 and the lateral seawall 3 of the seawall structure A ₁ , A ₂ , A ₃ ... It is possible to maintain a stable beach without being washed away.

In the above-mentioned revetment structure, when the width of the longitudinal revetment 1 or the width of the longitudinal revetment 1 and the lateral revetment 3 is set to a width of 1 m or more so that people or vehicles can pass through,
Along the longitudinal revetment 1 from the shore, the revetment structure A ₁ ,
It becomes possible to easily reach the sandy beach formed in the water area surrounded by A ₂ , A ₃ ... And the sandy beach can be effectively used as a place for leisure and recreation. At that time, stairs or slopes may be installed on the vertical revetment 1 and the lateral revetments 3 and 3'to make the beach go up and down.

In constructing the revetment structure of the present invention,
The material and construction method of the longitudinal seawall 1 and the lateral seawalls 3 and 3 ′ are not particularly limited, and any of the materials and construction methods conventionally used in seawall construction can be adopted.
The longitudinal revetment 1 and the lateral revetment 3 are, for example, various types of wave-dissipating blocks (tetrapot, hexapod block, beehive, V block, four-sided pyramid block, three-sided pyramid block, mat block, metacross, three-piece block, gamma-el block. Block, shake block, hollow triangular block, tripod block, asterod, pentagon, gassho block,
Akmon Block, Koken Block, Triver, Dross, Dugong, etc.), concrete caisson, cement,
It can be formed using a tile, a steel material, a composite material thereof, or the like.

In the above case, the vertical revetment 1 and the lateral revetments 3, 3'are used to produce a large amount of latance when manufacturing a fume tube, a pearl pile, a centrifugal tube such as a utility pole, or the like.
If you use a material made of concrete or cement that uses a large amount of pulp that is discharged at a paper mill, incineration residue that is discharged during garbage incineration, construction waste materials, coal ash, slag, etc. At the same time, effective utilization of those wastes that have been difficult to handle can be achieved.
In addition, when the vertical revetment 1 and the lateral revetments 3 and 3'are formed of concrete, cement or the like mixed with a fiber reinforcing material such as synthetic fiber or natural fiber, a revetment structure excellent in durability and strength can be obtained.

Furthermore, in some cases, natural rocks, coral reefs, etc. are used as they are for cutting work and the like, and a revetment in which two or more lateral revetments 3, 3'are provided for the longitudinal revetment 1. A structure may be formed, and two or more structures may be provided on the shore or in the vicinity of the structure toward the offshore, thereby performing wave breaking, erosion prevention, sand blast prevention, etc., and artificially forming a beach. .

Then, a revetment structure consisting of the longitudinal revetment 1 and two or more lateral revetments 3, 3'arranged at intervals is formed at the shore or a place adjacent to the shore by construction work or cutting work. In this case, water and waves on the vertical revetment 1 and the lateral revetment 3 are not completely impermeable to water.
It is preferable to provide voids or holes through which air or the like can pass in order to impart durability to the seawall. Then, in the revetment construction method of the present invention, the revetment structure A ₁ , A ₂ , A composed of the vertical revetment 1 and the lateral revetment 3, 3 ′ described above.
Other equipment may be installed or construction may be performed outside of ₃ , ...

[0031]

According to the revetment method and revetment structure of the present invention, the waterside shore such as a shore, a river shore, a lake shore, a pond shore, an artificial island shore, a harbor shore, or the like, It can be strongly prevented from being eroded by waves and winds, and is extremely excellent in the wave-dissipating action and the sand-scattering preventing action, and can exhibit a good revetment action. Along with that, in the water area surrounded by the revetment structure of the present invention, people can enjoy,
The flora and fauna that inhabit the waterside live, or it is possible to artificially form a large area sandy beach where microorganisms can live extremely smoothly, and such a sandy beach formed by the revetment method and revetment structure of the present invention, In recent years, the number of sand beaches that can be enjoyed by humans has become extremely small, and the number of important sand beaches due to flora and fauna and microorganisms living on the waterfront has been decreasing year by year.

[Brief description of drawings]

FIG. 1 is a diagram showing a conventional seawall construction method.

FIG. 2 is a view showing a typical example of a revetment method and revetment structure of the present invention.

FIG. 3 is a diagram showing another example of the revetment method and revetment structure of the present invention.

FIG. 4 is a diagram showing another example of the revetment structure of the present invention.

FIG. 5 is a view showing a state in which a sand beach is formed in a water area surrounded by the revetment structure of the present invention.

[Explanation of symbols]

A ₁ Revetment structure A ₂ Revetment structure A ₃ Revetment structure a Sandy beach 1 Longitudinal revetment 2 Shore 3 Lateral revetment 3'Horizontal revetment

Claims (3)

[Claims] 1. A vertical revetment extending offshore and at least two of the longitudinal revetments provided at intervals.
A revetment method, characterized in that two or more revetment structures having at least one lateral revetment are installed at intervals from the shore or a place adjacent to the shore toward the offshore. 2. A longitudinal revetment extending offshore and at least two of the longitudinal revetments provided at intervals.
A revetment structure, characterized in that two or more revetment structures having one or more lateral revetment are installed at intervals from the shore or a place adjacent to the shore toward the offshore. 3. A vertical revetment extending offshore and at least two of the longitudinal revetments provided at intervals.
A seawall structure with one or more lateral seawalls.