JPH0462214A - Artificial beach - Google Patents

Abstract

PURPOSE:To effectively utilize remaining land by a method in which the bank of revetment and steep beach, a dam consisting of microorganismcontact material provided in the surrounding sea area, and a beach-forming material consisting of microorganism-contact material provided between the bank and the dam are provided. CONSTITUTION:A semi-circular dam 2 is formed offshore of an existing revetment 1, and the dam 2 made of crushed stones of a trapezoidal cross section as microorganism-contact material is fixed to the seabed. A beach-forming material 3 such as crushed stone or gravel as microorganism-contact material is deposited between the revetment 1 and the dam 2 in such a way as to lower its surface toward the dam 2 from the revetment 1. The surface of the material 3 is made higher than sea surface L at high tide and the lowest bottom is made lower than the dam 2. Sea water passing through the material 3 and the dam 2 is clarified biologically. The remaining land can thus be effectively utilized by forming artificial beach around the existing revetment.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to an artificial beach having a structure suitable for construction on a steep beach or seawall and having self-cleaning ability.

``Conventional technology and its challenges'' In recent years, urban ports have been reclaimed, and waterfronts have been surrounded by artificial upright seawalls, creating seashores that prioritize industry and functionality. In response, there is a growing social need for beaches where people can enjoy the water in order to restore nature and enrich their lives.

In particular, in recent years, many factories along the coast that were built during a period of rapid economic growth have been relocated to rural areas and dispersed, leaving only the seawall facilities remaining, and it has been desired to make effective use of them.

On the other hand, when creating a beach, conventionally, the flow of seawater is blocked to make it easier for sand to settle at the desired location, or beach creation materials such as sand are used.

However, the conventional artificial beaches have the problem that if the surrounding water quality is poor, the created beach will be contaminated, making it impossible to enjoy the water, making it unsuitable for urban waterfronts.

The present invention has been made in view of the above circumstances, and aims to provide an artificial beach that can effectively utilize the site of an existing seawall and is less likely to be contaminated.

"Means for Solving the Problems" The artificial beach of the present invention comprises a bank such as a seawall or a steep beach, a weir made of a microbial contact material provided in the surrounding sea area at a predetermined distance from the bank, and and a weir, the surface of the beach material descends as it goes from the shore to the weir, and the tip of the beach material is lower than the weir. It is characterized by being set so that the height is also low.

Alternatively, a structure may be adopted in which sand or the like with a small particle size is used as the beach material, and a water-permeable membrane is provided at the interface between the weir and the beach construction material.

``Effect'' When the water level in the surrounding sea area rises due to the ebb and flow of water, seawater can move to the shore through the weir and beach construction materials, and the other way is to move freely above the weir. Seawater moves to the side. The seawater that passes through the weir and the beach building material is purified by the action of biofilms that have grown on the surfaces of the broken stones and other materials that make up the beach building material.

In addition, when the water level in the surrounding sea area decreases due to the ebb and flow of the tide, seawater can move to the surrounding sea area through two routes: one path is to pass through the beach construction materials and the weir, and the other is to move freely above the weir. Seawater moves.

The seawater that passes through the beach construction materials and weir is then subjected to biological treatment again before being discharged into the surrounding sea area.

"Embodiments" Examples of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of an artificial beach according to the present invention, and reference numeral 1 in the figure indicates an existing seawall. The weir 2, which is provided in a semicircular shape offshore from the seawall 1, may be of the submerged embankment type as shown by the solid line in the figure, or may be of the embankment type as shown by the broken line. When using an embankment type,
Since the amount of seawater passing through the weir 2 and the beach construction material increases, the purification ability is further exhibited. The weir 2 is made of crushed stone such as broken stone as a microorganism contacting material, and is formed into a trapezoidal cross section, and is fixed to the seabed.

Between the seawall 1 and the weir 2, beach building materials 3 such as broken stones and gravel, which act as microbial contact materials, are deposited such that the surface thereof descends from the seawall toward the weir 2. The surface of this beach construction material 3 is set to be higher than the sea level even at high tide. Further, the lowest part of the beach construction material 3 is set to be lower than at least the weir 2. Furthermore, microorganisms and benthic organisms live in the gaps and surfaces of the broken stones and gravel that make up the beach construction material 3, and they have the property of physicochemically or biochemically purifying the seawater that passes through them. ing.

Next, the inflow and outflow of seawater at the artificial beach of this embodiment will be explained.

First, when the water level in the surrounding sea area 5 rises due to the ebb and flow of the tide, seawater has two paths: one path to move toward the sea wall through the weir 2 and the beach construction material 3, and the other path to move freely over the top of the weir 2. Seawater moves from the beach to the artificial beach side. Seawater passing through the beach building material 3 is purified by the action of biofilms that have grown on the surfaces of the weir 2 and the broken stones that make up the beach building material 3.

In addition, when the water level in the surrounding sea area 5 falls due to the ebb and flow of the tide, seawater flows through two routes: one path is to move to the surrounding sea area side through the beach construction material 3 and the bottle 2, and the other path is to move freely over the top of the weir 2. Seawater moves toward the surrounding sea area. Then, the seawater passing through the beach construction material 3 and the weir 2 undergoes biological treatment again and is then discharged into the surrounding sea area 51\.

According to the artificial beach of this example, it is possible to create an artificial beach around the existing seawall that is no longer needed due to the relocation of factories to local areas, etc., and it is possible to create an artificial beach near the existing seawall that was previously considered to be deep and dangerous. can be used effectively.

Moreover, the seawater in the sea area around the seawall is purified by flowing through the beach construction material 3 of the artificial beach, and a clean waterfront can be obtained. Furthermore, since the weir prevents beach construction materials from flowing out, it is possible to obtain a stable artificial beach over a long period of time.

Furthermore, if the base 2 is a completely submerged embankment, the area around the beach can be avoided from feeling enclosed, and the waterside scenery can be visually enjoyed.

Next, another embodiment of the artificial beach of the present invention will be described with reference to FIG. 2. In this embodiment, parts having the same configuration as those in the previous embodiment are given the same reference numerals, and the explanation thereof will be omitted.

The artificial beach of this embodiment uses sand with particles smaller in diameter than broken stones and gravel as the beach building material 3, and further includes the beach building material 3 and the weir 2.
Sand prevention sheet (water permeable membrane) such as mesh sheet 7 is placed at the interface of
is provided.

Microorganisms live between the particles of the sand used as the beach construction material 3 and on the surface of the sand, as in the previous example, and the seawater passing through these areas is purified with higher purification efficiency than in the case of the previous example. can do.

In the artificial beach of this embodiment, the seawater in the surrounding sea area is moved and purified by the ebb and flow of the tide, as in the previous embodiment.

According to the artificial beach of this embodiment, it is possible to achieve the same effects as those of the above-mentioned embodiments, and furthermore, it is possible to purify the sea area around the shore with high purification efficiency.

Note that the artificial beach of the present invention is not limited to the above-mentioned embodiments, and other modifications are also possible.

For example, the present invention can be applied even if the shore is not an existing seawall but is a steep beach.

"Effects of the Invention" The artificial beach according to claim 1 includes a shore such as a seawall or a steep beach, a weir made of a microbial contact material provided in the surrounding sea area at a predetermined distance from the shore, and a weir between the shore and the weir. A beach building material made of a microbial contact material is provided between the shore and the weir, and the surface of the beach material descends from the shore toward the weir, and the tip thereof is lower than the base. Because of this structure, it is possible to create an artificial beach around the existing seawall, which is no longer needed due to the relocation of factories to local areas, etc., and makes effective use of the area near the existing seawall, which was previously considered to be deep and dangerous. , hydrophilicity can be achieved.

Moreover, the seawater in the sea area around the seawall is purified by flowing through the beach construction material of the artificial beach, and a clean waterfront can be obtained. Furthermore, since the weir prevents beach construction materials from flowing out, it is possible to obtain a stable artificial beach over a long period of time.

Furthermore, if the base is a completely submerged embankment, the area around the beach can be avoided from feeling enclosed, and the waterside scenery can be visually enjoyed.

The artificial beach according to claim 2 uses sand or the like with a small particle size as the beach material, and has a structure in which a water-permeable membrane is provided at the interface between the base and the beach construction material, so that the sea area around the shore can be purified with high purification efficiency. Can be purified.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing one embodiment of the invention, and FIG. 2 is a side sectional view showing another embodiment of the invention. L...Sea level.

Claims (2)

[Claims] (1) From a weir consisting of a microbial contact material installed on a shore such as a seawall or a steep beach, and in the surrounding sea area at a predetermined distance from the shore, and a microbial contact material installed between the shore and the weir. An artificial beach equipped with a beach creation material, characterized in that the surface of the beach material descends from the shore toward the weir, and the tip thereof is provided so as to be lower than the weir. An artificial beach. (2) The artificial beach according to claim 1, wherein sand or the like having a small particle size is used as the beach material, and a water-permeable membrane is provided at the interface between the weir and the beach construction material.