JP2022035101A - Floating type sand beach growing unit and sand beach growing device using therewith - Google Patents

Abstract

To provide a floating type sand beach growing unit relatively easily constructible at low cost, surely and effectively exhibiting wave-dissipating action to effectively prevent damages by tsunami or tidal wave, and at the same time, contributing to growth of the sand beach.SOLUTION: A floating type sand beach growing unit is composed of a floating body 1 having an offshore side end part 2 directed to the off-shore side and a land side end part 3 directed to the land side and rocking following to the vertical movement of waves by the pivoted offshore side end part 2, a stand 4 erected in relatively shallow water of a coast part and pivoting the offshore side end part 2, and a receiving base 5 receiving the land side end part 3 of the floating body 1 and prevented in being buried into the seabed. The floating body is formed of multiple hollow pipes 6, the offshore side end part 2 of the hollow pipes 6 is pivoted at the stand 4 via a fixed frame 16, and intermediate parts of the pipes are connected by a wave receiving crosspiece 7.SELECTED DRAWING: Figure 1

Description

The present invention relates to a floating sand beach growing unit and a beach growing device using the same, and more specifically, it is installed in the water of the sea or a river to suppress wave force, thereby exhibiting a beach growing function. It relates to a floating beach growing unit and a beach growing device using it.

Conventionally, various wave-dissipating devices installed in relatively shallow waters along the coast have been considered in order to prevent damage caused by tsunamis and high waves. However, the wave-dissipating device that has been proposed in the past is not only expensive in itself due to its structure, but also has a drawback that it takes time and effort to install and the total cost increases. In order to eliminate this drawback, the present inventor has disclosed a wave-dissipating method and a wave-dissipating device having a simple structure, relatively low cost and installation cost of the device itself, and having an effective wave-dissipating effect (patented). No. 3609052).

The wave-dissipating device according to the present invention has one or more wave-dissipating bodies having a C-shaped cross section having an opening side surface extending in the length direction, and the opening side surface is directed in the traveling direction of the wave and tilted with respect to the traveling direction of the wave. It is installed in the relatively shallow water of the coastal area, and when a wave hits the offshore end of the wave-dissipating body, the water flow generated between the offshore end and the land-side end of the wave-dissipating body. The pressure difference makes it possible for a flow to occur inside the wave-dissipating body.

However, although this wave-dissipating device is cheaper than the conventional device, the cost of the wave-dissipating body itself including the fixed pile and the cost for its installation work are high, so that the cost of the wave-dissipating device is further reduced. Was longing for the appearance of. Further, in the case of the wave-dissipating device, a large gap may be formed between the wave-dissipating bodies at the time of installation, and a wave may escape from the gap, and the wave that has escaped may make the wave-dissipating action insufficient.

Therefore, the present inventor has an offshore end portion that is directed to the offshore side and a land side end portion that has a larger buoyancy than the offshore end portion and is directed to the land side, and the offshore end portion. A floating body that swings following the vertical movement of waves due to its pivotal support, a stand that stands in the water of relatively shallow water in the coastal area and pivotally supports the offshore end, and the land. A plurality of wave-dissipating bodies consisting of receiving means at the side ends are installed side by side at appropriate intervals and inclined in the horizontal direction with respect to the traveling direction of the wave, and the floating body is offshore of the wave-dissipating body. The side end is pivotally supported by the stand so as to be horizontal at low tide, and the land end is above the water level at low tide by the land receiving means. We have proposed a floating sand beach growing unit characterized by being held to prevent its burial on the seabed (Patent No. 5665822).

Patent No. 3609052 Patent No. 5665820

In the case of the floating sand beach growing unit related to this proposal, the expected sand beach growing effect has been achieved and the results have been achieved, but in the case of the device, a large number of bamboo or bamboo grass are mainly bundled as a floating body. Since it was used, there was a problem that it was easily damaged and its resistance to waves was easily reduced.

Therefore, the present invention has a simple and robust configuration, is highly durable, swings in response to waves, and exerts a strong resistance to waves to exert a wave-dissipating effect. It is an object of the present invention to provide a floating beach growing unit capable of growing a beach and a beach growing device using the floating beach growing unit while preventing the seabed from being scooped out by waves.

The invention according to claim 1 for solving the above-mentioned problems has an offshore end portion facing offshore and a land side end facing land, and the offshore end portion is a pivotal support. A floating body that swings in response to the vertical movement of the sea surface, a stand that stands in the water of relatively shallow water in the coastal area and pivotally supports the offshore end, and the land of the floating body. It consists of a pedestal that is installed below the side end and receives the land side end of the float and prevents its submarine burial.
The floating body is composed of a plurality of hollow pipes, the offshore end of the hollow pipe group is pivotally supported by the stand via a fixed frame, and the intermediate portion is connected by a wave receiving rail.
The wave receiving rail is a floating sand beach growing unit characterized in that the upper half is exposed to the upper side of the hollow pipe group and the lower half is exposed to the lower side in a state of being inclined to the offshore side.

In one embodiment, a weight member is attached to the offshore end of the fixed frame. Further, the hollow pipe is an FRP compose pipe having a length of about 10 m.

In one embodiment, the upper surface of the wave receiving rail is curved.

In one embodiment, the stand comprises means of regulating the upward rotating end of the floating body.

The invention according to claim 6 for solving the above problems is to tilt a plurality of floating beach growing units according to any one of claims 1 to 5 with respect to the traveling direction of a wave, and to incline each unit. It is a floating sand beach growing device that is arranged at appropriate intervals so that the ends of the beaches are linear.

The present invention is as described above, has a simple and robust configuration, is highly durable, swings and stands in response to waves, and exerts strong resistance to waves to extinguish waves. It has the effect of preventing the seabed from being scooped out by the waves and growing sandy beaches.

It is a side view which shows the installation state of the floating type sand beach cultivation unit which concerns on this invention. It is a top view of the floating type sand beach cultivation unit which concerns on this invention. It is a side view which shows the wave receiving rail in the floating type sand beach cultivation unit which concerns on this invention. 3A is an EE view and an EF view is shown in FIG. It is a side view of AA in FIG. It is a plan view which shows the fixed frame in the floating type sand beach growing unit which concerns on this invention, and is the DD line sectional view enlarged view. FIG. 3 is a cross-sectional view taken along the line CC and a perspective view showing a holding frame in the floating sand beach growing unit according to the present invention. It is a figure which shows the installation state of the floating type sand beach growing apparatus which concerns on this invention. It is a figure which shows the operation of the floating type sand beach growing apparatus which concerns on this invention.

When the sea level rises and the waves rise due to the influence of low pressure such as typhoons, so-called bottom roughness occurs and the sand on the seabed rises, and the sand that rises is carried to the land side by the tidal current. However, the sand carried to the land side is returned to the offshore side again by the flow to the offshore side, especially the rip current. Therefore, even if the sandy beach is scraped by the rip current, it will not be cultivated. This rip current occurs when the waves push seawater from offshore to the shore and the seawater stored on the shore tries to return to the shore. The sand carried to the land side will stagnate and gradually accumulate, so it will be possible to grow sandy beaches.

The present inventor has completed the present invention based on the above understanding of the providence of nature. Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. As shown in FIGS. 1 to 3, the floating sand beach growing unit according to the present invention has an offshore end portion 2 directed to the offshore side and a land side end portion 3 directed to the land side when installed in the sea. The floating body 1 that swings in response to the vertical movement of the sea surface due to the pivotal support near the offshore end 2 and the floating body 1 that is erected in the relatively shallow water of the coastal area and offshore. A stand 4 that pivotally supports the side end portion 2 and a pedestal 5 that is installed below the land side end portion 3 of the floating body 1 to receive the land side end portion 3 of the floating body 1 and prevent its submarine burial. It consists of (Fig. 1).

The floating body 1 is composed of a plurality of hollow pipes 6 in which the vicinity of the offshore end portion 2 is pivotally supported by the stand 4 and the intermediate portion is connected by the wave receiving rail 7 (FIG. 2). As the hollow pipe 6, it is recommended to use, for example, an FRP compose pipe having a length of about 10 m, which is lightweight and does not have to be corroded by seawater. 5 to 10 hollow pipes 6 are juxtaposed at appropriate intervals (6 in the illustrated example).

The wave receiving rail 7 is a horizontally long semi-cylindrical material having a flat cross section, and is attached so as to gather a group of hollow pipes 6 in a state of being inclined to the offshore side, and a plurality of hollow pipes 6 are integrated to stabilize the floating operation. As shown in FIGS. 3 and 4, for example, the wave receiving rail 7 has an insertion hole 8 for inserting the hollow pipe 6 inserted diagonally by several minutes of the hollow pipe 6 in the intermediate portion thereof. ..

The method of fixing the wave receiving rail 7 to the hollow pipe 6 group is arbitrary, but for example, the base plate 9 bolted to the back surface of the wave receiving rail 7 and the base plate 9 at intervals corresponding to the outer diameter of the hollow pipe 6 A fixing means consisting of a pair of bent holding plates 10 and 11 fixed to the can be used. When this fixing means is used, each hollow pipe 6 is inserted into the insertion hole 8 through the upper and lower holding plates 10 and 11, and after being moved to a predetermined position as it is, the upper and lower holding plates 10 and 11 are connected to a large number of bolts. Tighten by 12 (FIGS. 3 and 4). Thus, the upper half of the wave receiving rail 7 is exposed to the upper side of the hollow pipe group 6 in a state of being inclined to the offshore side, and the lower half is exposed to the lower side thereof.

The stand 4 is erected in relatively shallow water 100 to 200 m offshore and pivotally supports the offshore end 2 of the floating body 1. The stand 4 is configured, for example, by assembling a pair of columns 14, 14 and a cross member 15 in an H shape, and the columns 14, 14 are erected on the seabed (FIG. 5). Then, a fixed frame 16 that fixedly supports and supports the offshore end portion 2 of the floating body 1 is swingably attached between the columns 14 and 14 of the stand 4. For this purpose, for example, a shaft hole 17 is formed in the side plate of the fixed frame 16, and a short shaft 18 attached to the columns 14 and 14 is fitted therein (FIG. 6).

The fixed frame 16 is a quadrangular frame for fixing the offshore end portion 2 of the floating body 1, and the hollow pipes 6 groups are fixed to the end portion and the intermediate portion of the upper surface thereof via the holding frame 20. The holding frame 20 is an angle material in which semi-circular notches 21 corresponding to the diameter of the hollow pipe 6 are arranged side by side (FIGS. 5 and 7), and the upper half of the hollow pipe 6 is arranged in each notch 21 from above. After fitting, the holding frame 20 is bolted to the fixed frame 16 by the bolt 22. If necessary, the weight member 23 is attached to the back end of the fixed frame 16 (FIG. 6). As will be described later, the weight member 23 serves to assist the rise of the hollow pipe 6 group.

The pivotal position of the floating body 1 on the stand 4 is set to a height position at which the floating body 1 becomes horizontal at low tide. This height corresponds to the height of longshore drift from offshore and the height of the sea surface when passing offshore current, and by making the height of the pivot position of the floating body 1 in this way, each floating It is prevented as much as possible that the type sand beach cultivation unit is exposed on the surface of the water and the seascape is spoiled. This height adjustment can be performed by changing the installation position of the short shaft 18 of the columns 14, 14 or changing the burial depth of the columns 14, 14.

In a preferred embodiment, the stand 4 is provided with a stopper 25 that regulates the standing angle of the floating body 1 to prevent inversion. For example, the stopper 25 is projected inward from the columns 14 and 14 on the lower side of the fixed frame 16 (see FIGS. 1 and 5). In this case, when the floating body 1 rotates and stands up in a vertical state, the fixed frame 16 hits the stopper 25, so that further rotation is prevented.

Further, on the lower side of the land side end portion 3 of the floating body 1, a cradle 5 for receiving the land side portion of the floating body 1 and preventing its burial on the seabed is installed. The pedestal 5 is an inverted U-shaped object having a length longer than the width of the floating body 1, and its height is almost the same as the pivot position height of the offshore end portion 2 of the floating body 1, and the floating body 5 is formed. Keep 1 above the water level at low tide of spring tide (Fig. 1). In that case, since the floating body 1 is received by the cradle 5, a space that allows the passage of the rip current is always secured between the floating body 1 and the seabed, so that the drift sand is carried to the land side. The rip current flows offshore without any hindrance by the float 1.

To elaborate on this point in more detail, the waves that arrived in the shallows after the seafloor slope became rip currents and returned to the offshore side, but the waves on the land side of each floating sand beach cultivation unit lost their momentum. Therefore, when returning as a rip current, it quietly passes through the space secured under each floating body 1. If such a space is not secured here, the rip current will be blocked there, a swirl flow will occur in the vicinity, and the sand on the seabed will be eroded, making it difficult to grow sandy beaches. ..

Further, the floating body 1 is received by the cradle 5 and prevented from being buried in the seabed, so that seaweeds, shellfish, wreckage, etc. are entangled with the seabed burial, and the weight of the floating body 1 makes it impossible to ascend and has a wave-dissipating effect. Is surely prevented from fading. Further, since the cradle 5 is installed at a height that holds the floating body 1 above the water level at the low tide of the spring tide, the land side end portion 3 of the floating body 2 is exposed to the sea surface at the low tide of the spring tide. become. Thus, the seaweeds and shellfish entwined with the land side end 3 (although not as much as when buried in the seabed, some floating seaweeds and the like are entwined) are dried and blown away by the wind, so that the buoyancy of the floating body 1 is maintained. Will be done.

The floating beach growing device according to the present invention has a large number of floating beach growing units having the above configuration, each of which is tilted horizontally by, for example, about 20 to 45 degrees with respect to the traveling direction of the wave, and each unit. Are arranged at appropriate intervals so that the ends of the above are linear (see FIGS. 8 and 9). The installation position is preferably a place where white waves stand on the boundary between deep and shallow areas in water 100 to 200 m offshore of the coast. The traveling direction of the wave is determined by the seafloor topography of the coast.

By installing the floating sand beach growing unit according to the present invention as described above, a sand beach growing effect can be obtained at the same time as a wave-dissipating effect. That is, the incident wave w1 arriving toward each floating beach growing unit hits each floating beach growing unit, and a part of the incident wave is dispersed and extinguished by passing through the device, and a part of the wave is refracted by about 90 degrees. It becomes the reflected wave w2 (see FIG. 9).

However, each floating beach growing unit is installed so as to incline in the horizontal direction, for example, about 20 to 45 degrees with respect to the traveling direction of the wave, and the end of each unit is linear. In order to be installed, the incident wave w1 does not hit one floating beach growing unit at the same time over the entire width, but the time to hit the floating beach growing unit located on the most offshore side (earliest). ) And the time (latest) to hit the floating sand beach growing unit located on the most land side. That is, the refracting portion from the incident wave w1 to the reflected wave w2 moves along each unit inclined with respect to the traveling direction of the wave, and a wave-dissipating action occurs in the process.

As described above, the incident wave w1 hits each floating sand beach growing unit, and a part of the incident wave w1 passes through the gap between the units having a low water flow pressure to the land side, so that the incident wave w1 is dispersed and extinguished. Then, along with the dispersed wave extinguishing of the incident wave w1, a stagnation area of drift sand due to the wave extinguishing occurs on the land side of the floating sand beach growing unit, and the drift sand accumulates there, and as a result, the beach gradually becomes sandy. Will be nurtured. Since the floating body 1 stands up following the rise in the water level, the wave-dissipating action is not lost depending on the water level.

In particular, in the case of the floating sand beach growing unit according to the present invention, the wave receiving bar 7 exists in the middle portion of the floating body 1, and the portion exposed below the floating body 1 of the wave receiving bar 7 floats. The incident wave w1 coming to the lower side of the body 1 is extinguished, and at that time, the ascending force from the incident wave w1 is received to promote the swinging upright of the floating body 1 to which the offshore end portion 2 is pivotally supported. do. Further, since the wave receiving rail 7 has a slightly flattened semi-cylindrical shape and a curved upper surface, lift is generated by the waves flowing on the wave receiving rail 7, and the lift is also promoted. In addition to this, since the standing up is promoted by the action of the weight member 23, the floating body 1 surely swings upright in response to the rise in the water level and continues to exert the wave-dissipating function.

The seawater that hits the slope from the deep seabed to the shallow water becomes an ascending wave that rises diagonally upward along the slope. Since the wave receiving rail 7 receives this rising wave from the lower side, the swinging upright of the floating body 1 is further promoted, and the floating body 1 acts as a resistance to extinguish the wave while rotating upward. Further, even when this rising wave rises offshore of the present device and shatters onto the floating body 1, the wave force is attenuated by the resistance of the floating body 1. The incident wave w1 heading toward the land side is also weakened by being affected by this rising wave.

The floating sand beach growing unit and the sand beach growing device using the floating sand beach growing unit according to the present invention are as described above, have a simple and robust configuration, are highly durable, and swing and stand in response to waves. By exerting a strong resistance to the waves, it exerts a wave-dissipating effect, which prevents the seabed from being scooped out by the waves and has the effect of nurturing sandy beaches. The industrial applicability is great.

1 Floating body
2 Offshore end 3 Land side end 4 Stand 5 Stake 6 Hollow pipe 7 Wave receiving rail 8 Insertion hole 9 Base plate 10, 11 Holding plate 12 Bolt 14 Strut 15 Cross member 16 Fixed frame 17 Shaft hole 18 Short shaft 20 Holding frame 23 Weight material 25 Stopper

Claims (6)

It has an offshore end facing the offshore side and a land side end facing the land side, and when the offshore end is pivotally supported, it floats in response to the vertical movement of the sea surface. The body, a stand that stands in the water of a relatively shallow coastal area and pivotally supports the offshore end, and a stand that is installed below the land end of the float and said that the float. It consists of a cradle that receives the land-side end and prevents its submarine burial.
The floating body is composed of a plurality of hollow pipes, the offshore end of the hollow pipe group is pivotally supported by the stand via a fixed frame, and the intermediate portion is connected by a wave receiving rail.
The wave receiving rail is a floating sand beach growing unit characterized in that the upper half is exposed to the upper side of the hollow pipe group and the lower half is exposed to the lower side in a state of being inclined to the offshore side. The floating sandy beach growing unit according to claim 1, wherein a weight member is attached to the offshore end of the fixed frame. The floating sandy beach growing unit according to claim 1 or 2, wherein the hollow pipe is an FRP compose pipe having a length of about 10 m. The floating sand beach growing unit according to any one of claims 1 to 3, wherein the upper surface of the wave receiving rail is a curved surface. The floating sandy beach growing unit according to any one of claims 1 to 4, wherein the stand includes means for regulating an upward rotating end of the floating body. A plurality of floating beach growing units according to any one of claims 1 to 5 are inclined with respect to the traveling direction of the wave, and the ends of the units are arranged at appropriate intervals so as to be linear. Floating sandy beach growing device.

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