JPH0559684B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <<Industrial Application Field>> The present invention relates to a method for constructing an artificial fishing reef, and particularly relates to a method for constructing an artificial fishing reef by on-site construction.

<<Prior Art>> Generally, it is difficult for fish to breed on a flat seabed surface, so artificial fishing reefs are often constructed on this type of seabed surface and used as fishing grounds.

Generally, these artificial reefs are constructed using a method in which blocks are formed on land, transported to the site where the reef is to be constructed, and then submerged.

[Problems to be solved by the invention] However, according to this method, there is a limit to the size of the block due to transportation power and production equipment on the ground, and it is not possible to create a large fishing reef. .

As an alternative to this construction method, methods are being considered to create artificial reefs by dumping earth and sand into the ocean floor.
The introduced soil separates into pieces in the water, with the coarse particles settling first and the fine particles becoming suspended in the water, which does not result in a homogeneous soil cover, and there is also the problem that the water quality becomes polluted when the soil is introduced. Furthermore, due to water currents and the slope of the bottom, the reef gradually becomes flattened and becomes useless as a fishing reef.

This invention was made in view of the above problems, and its purpose is to construct an artificial fishing reef by on-site construction, and to create a material that solidifies the earth and sand as a material for the fishing reef in a non-separable state in water. The purpose is to provide a method that can be used to construct a large fishing reef.

<<Means for Solving the Problems>> In order to achieve the above-mentioned object, this invention sinks a formwork formed into an appropriate shape on the bottom of the water, and deposits earth and sand within the formwork and/or between the formwork, The method is characterized in that an artificial fishing reef is constructed on the bottom of the water by introducing a sand and sand composition for fishing reefs having a composition comprising a binder that binds the particles of the sand and suppresses their separation, and after curing, the formwork is pulled up. do.

<<Example>> Hereinafter, preferred embodiments of the present invention will be described in detail using the accompanying drawings.

1 to 4 show an embodiment of a method for constructing an artificial fishing reef to which the present invention is applied.

First, in FIG. 1, a formwork 4 for the artificial reef is transported by a crane ship 2 to the seabed 1 on which the artificial reef is planned to be constructed, and the formwork 4 is then transported by a crane 3 attached to the crane ship 2 to be constructed. It will be deposited on the ocean floor.

The formwork 4 has an outer frame shape suitable for a fishing reef, and although its height and outer circumference are extremely bulky, it is lightweight and can be assembled at the construction site.

After the work of sinking the formwork 4 is completed, as shown in FIG. 2, the bucket boat 5 is brought close to the crane boat 2, and the bucket boat 7 suspended from the tip of the crane 6 installed on the bucket boat 5 is dropped into the water. Open Bucket 7,
A fishing reef sediment composition 8 is put into the formwork 4.

The earth and sand composition 8 is composed of ordinary earth and sand and a binder that binds particles of the earth and sand and suppresses separation thereof.

The binder includes a binder that imparts caking properties between the earth and sand particles and ensures a predetermined fluidity, and a hardening agent that hardens between the earth and sand particles to solidify the earth and sand.

The binder is made of a water-soluble natural, semi-synthetic or synthetic polymer, and has the function of preventing the separation of particles and the incorporation of water through a kind of glue-like substance.

To explain the binder specifically, water-soluble natural polymers include various starches, konjac, funori,
Agar, sodium alginate, algae, tragonth gum, acacia, dextrin, levan, glue, gelatin, casein, collagen, etc. are used.

Examples of water-soluble semi-synthetic polymers include viscose, methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, carboxymethylcellulose,
Soluble starch, carboxymethyl starch, dialdehyde starch, etc. are used.

As the water-soluble synthetic polymer, polyvinyl alcohol, sodium polyacrylate, polyacrylamide, polyethylene oxide, etc. are used.

The curing agent is one selected from ordinary Portland cement, blast furnace cement, flyash cement, other cement materials, lime-based materials such as slaked lime, asphalt-based materials, and blast-furnace slag-based materials, or a combination thereof. . This type of curing agent has the function of solidifying and stabilizing the soil quality of the earth and sand after being added, and improving its strength.

In addition, the blending ratio of each binder and hardening agent to the earth and sand should be determined by taking into account economic efficiency and the degree of hardening achieved: 1 to 5 parts by weight of the binder and 50 to 300 parts by weight of the hardening agent to 1000 parts by weight of the earth and sand. is the most preferable value.

Furthermore, these compositions 8 are mixed with water and transferred in a slurry state from the bucket 7 into the formwork 4, and although there is almost no risk of suspension compared to general earth and sand, there is no risk of suspension until hardening. In order to prevent some degree of suspension during the process, the mixture is kept in a so-called hard kneaded state.

The charged composition 8 is then solidified and deposited in the mold 4 in order. The amount of composition 8 to be charged is determined by the number of times the bucket 7 is charged, depending on the volume of the formwork 4 and the capacity of the bucket 7 to be conveyed at one time. After almost all of the composition 8 is filled inside the mold 4, the composition 8 is completely cured within the mold 4 by leaving it for a certain period of time.

Thereafter, as shown in FIG. 3, if the formwork 4 is lifted up by the crane 3, an artificial fishing reef 9 formed in the shape of a formwork can be constructed on the seabed 1, as shown in FIG. can.

These artificial fishing reefs 9, as shown in Figure 4,
By regularly arranging them at specified intervals,
A fishing reef 9 consisting of mountains and valleys is continuously formed on the ocean floor, providing the most favorable topography for the reproduction of fish.

In addition, in the above example, the composition 8 was placed inside the formwork 4.
Although the embodiment of the present invention is not limited to this, the composition 8 may be filled between a plurality of molds 4 by sinking them.

Further, for filling the composition 8, not only the bucket 7 but also a tremie tube may be used to pump the composition 8.

<<Effects of the Invention>> As explained in detail in the embodiments above, according to the method for constructing an artificial fishing reef according to the present invention, after the formwork is sunk to the bottom of the water, hardening earth and sand are formed in the formwork or between the formworks. Fishing reefs are built on the water bottom through a series of on-site construction steps, such as putting in the composition and then pulling up the formwork, compared to the conventional construction method of transporting blocks and dropping them onto the water bottom. Can create large fishing reefs. In addition, the artificial reef constructed as described above is less likely to lose its shape than ordinary earth and sand, can maintain its shape according to the shape of the formwork, and does not cause problems such as water pollution during construction. do not have.

[Brief explanation of the drawing]

1 to 4 are explanatory diagrams showing one embodiment of a method for constructing an artificial fishing reef to which the present invention is applied. 1... Seabed surface, 4... Formwork, 8... Sediment composition for fishing reef, 9... Artificial fishing reef.

Claims (1)

[Claims] 1 A formwork formed into an appropriate shape is sunk to the bottom of the water,
A fishing reef sediment composition consisting of earth and sand and a binder that binds the particles of the earth and sand and suppresses their separation is put into the form and/or between the form, and after curing, the form is pulled up. A method for constructing an artificial fishing reef, characterized in that the artificial fishing reef is constructed on the bottom of the water.